Source: NORTH CAROLINA STATE UNIV submitted to
INFLUENCE OF ORCHARD MANAGEMENT SYSTEMS ON TREE FRUIT GROWTH AND PRODUCTIVITY
Sponsoring Institution
National Institute of Food and Agriculture
Project Status
REVISED
Funding Source
Reporting Frequency
Annual
Accession No.
0152343
Grant No.
(N/A)
Project No.
NC06196
Proposal No.
(N/A)
Multistate No.
(N/A)
Program Code
(N/A)
Project Start Date
Oct 1, 2010
Project End Date
Sep 30, 2015
Grant Year
(N/A)
Project Director
Parker, M. L.
Recipient Organization
NORTH CAROLINA STATE UNIV
(N/A)
RALEIGH,NC 27695
Performing Department
Horticultural Science
Non Technical Summary
Peach tree short life (PTSL) is one of the limiting factors in commercial peach production in the sandier soils of eastern North Carolina. At present, rootstock selection provides one of the greatest opportunities to minimize, although not eliminate, the incidence of PTSL. Previous research in North Carolina has shown peach growers in the southeast that when replanting peach trees in PTSL prone sites the importance of using Guardian rootstock and preplant fumigation to minimize the potential for PTSL and increase orchard productivity and profitability. In addition, even in soils that have been fallow for more than five years, initial data indicate that greater yields and tree survival are achieved with preplant fumigation and the use of the Guardian rootstock. Ongoing studies are evaluating newer Guardian selections to find a rootstock that is completely resistant to PTSL without the need for preplant soil fumigation. This research is also evaluating different cultivars of peaches and Asian pears that can be commercially grown in the higher elevations of NC. Through research-based investigation another goal of this program is to help growers identify and commercially grow high-value tree fruit that can provide consumers with high-quality "locally grown" fruit.
Animal Health Component
90%
Research Effort Categories
Basic
5%
Applied
90%
Developmental
5%
Classification

Knowledge Area (KA)Subject of Investigation (SOI)Field of Science (FOS)Percent
1021114106010%
2051110106010%
2051114106050%
2051115106010%
2051119106020%
Goals / Objectives
GOALS and OBJECTIVES: a) Develop components of a successful peach orchard management system to increase tree survival, orchard productivity and ensure consistent cropping in North Carolina, to include preplant soil fumigation, cultivar selection and rootstock selection. b) Evaluate plant growth regulators for commercial use in peach production for such responses as fruit thinning, delaying fruit maturity and increasing post harvest quality. c) Evaluate the commercially available, newly released and pending North Carolina peach cultivars for commercial potential in western NC. d) Identify and evaluate potential alternative or specialty tree fruit crops suitable for North Carolina climatic conditions such as pecans, pears, Asian pears, persimmons, and pawpaws. EXPECTED OUTPUTS: Results from this project will be disseminated through annual grower meetings, field days, newsletters and regional meetings. In addition, cooperative extension agents will be informed of the results through in-service training and individual consultations.
Project Methods
a) A third generation peach rootstock trial was initiated at the Sandhills Research Station in 2008 to evaluate peach tree survival, productivity and growth of 12 advanced GuardianTM selections. GuardianTM is tolerant to ring nematodes and peach tree short life (PTSL). The GuardianTM selections are from the breeding program at Clemson University. b) Peach growth regulators will be evaluated as they become available at the Sandhills Research Station. In 2002-2005, various formulations of abscissic acid (ABA) were applied to peaches to determine if there is any commercial merit to using ABA in peach production evaluating parameters from water usage, effect on dormancy and bloom delay or enhancing fruit quality. Several products for bloom thinning were also evaluated. Several organic formulations of pine and corn oil were used and compared to ammonium thiosulfate for thinning activity. The experiments were set-up with a randomized complete block design with six replications. c) In 2001, 15 cultivars and selections of peaches, primarily NC developed cultivars, with both white and yellow flesh were planted at the Mountain Horticultural Crops Research Station, Mills River, NC. Seven additional selections were planted in 2002 with superior traits such as cold hardiness, white flesh, low acidity, late ripening or doughnut shaped (peento-type). Trees are being grown under commercial conditions and not irrigated for frost protection to evaluate the cropping consistency of these cultivars. In addition, the peach cultivars are being evaluated by individuals for fruit quality (firmness, sweetness, etc.) during the season as a reflection of consumer preference. d) In 2010, 11 cultivars of pear, two European pears and nine Asian pears, were planted at the Mountain Horticultural Crops Research Station, Mills River, NC. The trees will be grown under commercial conditions and evaluated for survival, growth and productivity. A major concern, which will be evaluated, is the fire blight bacteria (Erwinia amylovora)which is a limiting factor in producing many cultivars of pear in North Carolina. Efforts will be conducted to inform and demonstrate to fruit growers of the opportunities to sustainably and profitably grow tree fruit in North Carolina.

Progress 10/01/11 to 09/30/12

Outputs
OUTPUTS: The results from this project have been presented to commercial fruit growers and associated communities of interest in NC via educational programs an Annual Meetings, tours to the plantings (July) and written reports. PARTICIPANTS: Dr. David Ritchie, Plant Pathology Collaborator Mr. Tom Hoyt - Research Technician responsible for data collection and daily operations Ms. Bernadette Clark - Research Technician responsible for data collection and analysis TARGET AUDIENCES: The research for this project is conducted at the Sandhills Research Station, Jackson Springs and the Mountain Horticultural Crops Research Station (MHCRS), Mills River, NC. Data and information generated from these trials are presented at grower meetings and the research is being conducted to benefit commercial growers, county extension agents and enthusiasts. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.

Impacts
Peach tree short life (PTSL) is one of the limiting factors to commercial peach production in the sandier soils of North Carolina and the SE United States. The peach rootstock, Guardian, is reported to be tolerant to both root-knot and ring nematodes. Ring nematodes contribute to the incidence of peach tree short life (PTSL). This research has led to the current recommendations in the Sandhills region that when planting peach trees in PTSL prone sites that Guardian rootstock and preplant fumigation must be used to minimize the potential for PTSL and increase orchard productivity and profitability. Ongoing second generation trials, in cooperation with Clemson University, were planted in 2008. In addition, ground cover plantings are in place at the Mountain Horticultural Crops Research Station, Mills River and the Sandhills Research Station, Jackson Springs evaluating tree growth and productivity with varying degrees of vegetation-free area under peach trees with and without irrigation. This is scheduled to be a 10 yr. project and at the end of the 7th year, the treatments with the greater vegetation-free area are the most productive. This project also encompasses a large scale peach planting in the western part of the state at the Mountain Horticultural Crops Research Station, Mills River. This planting was initiated in 2001 with 15 cultivars planted and another eight planted in 2002 with primarily NC cultivars and selections, and included both white and yellow fleshed cultivars and several peento selections. This research has shown that peach production can be accomplished in the mountains of NC and there are commercial orchards being established. Spring frost/freeze events are a potential threat to many of the earlier blooming cultivars in many years. This is reflected in the cumulative yields through 2012. This research is identifying NCSU developed cultivars that will crop consistently over the long term that will be the most profitable for growers such as Challenger, Intrepid, Contender and China Pearl which had a greater yield per tree than lower chilling cultivars such as Carolina Belle, Winblo and Biscoe. Sporadic tree decline, possibly due to X-disease, has also been an issue in this planting and trials are underway using laboratory PCR analysis to determine what pathogens may be involved in this tree death. Studies are also been conducted to evaluate plant growth regulating products on tree growth, bloom thinning and postharvest fruit characteristics with only preliminary results at present.

Publications

  • Parker, M.L. and S.M. Blankenship. 2012. Postharvest response of peach and nectarine cultivars to 1-Methylcyclopropene treatment. Acta Hort. 962:403-409.
  • Parker, M.L., C. Campbell, and B.M. Clark. 2012. Abscisic acid applications in peach. Acta Hort. 962:549-555.


Progress 10/01/10 to 09/30/11

Outputs
OUTPUTS: The results from this project have been presented to commercial fruit growers and associated communities of interest in NC via educational programs an Annual Meetings, tours to the plantings (July) and written reports. PARTICIPANTS: Dr. David Ritchie, Plant Pathology Collaborator Mr. Tom Hoyt - Research Technician responsible for data collection and daily operations Ms. Bernadette Clark - Research Technician responsible for data collection and analysis Provided training for peach growers and NCSU field faculty in July at the Sandhills Research Station, Jackson Springs TARGET AUDIENCES: The research for this project is conducted at the Sandhills Research Station, Jackson Springs and the Mountain Horticultural Crops Research Station (MHCRS), Mills River, NC. Data and information generated from these trials are presented at grower meetings and the research is being conducted to benefit commercial growers, county extension agents and enthusiasts. PROJECT MODIFICATIONS: Not relevant to this project.

Impacts
Peach tree short life (PTSL) is one of the limiting factors to commercial peach production in the sandier soils of North Carolina and the SE United States. The peach rootstock, Guardian, is reported to be tolerant to both root-knot and ring nematodes. Ring nematodes contribute to the incidence of peach tree short life (PTSL). This research has led to the current recommendations in the Sandhills region that when planting peach trees in PTSL prone sites that Guardian rootstock and preplant fumigation must be used to minimize the potential for PTSL and increase orchard productivity and profitability. In addition, even in soils that have been fallow for more than five years, data indicate that greater yields and tree survival are achieved with preplant fumigation and the use of the Guardian rootstock. Ongoing second generation trials, in cooperation with Clemson University, were planted in 2008. In addition, ground cover plantings are in place at the Mountain Horticultural Crops Research Station, Mills River and the Sandhills Research Station, Jackson Springs evaluating tree growth and productivity with varying degrees of vegetation-free area under peach trees with and without irrigation. This is scheduled to be a 10 yr. project and at the end of the 6th year, the treatments with the greater vegetation-free area are the most productive. This project also encompasses a large scale peach planting in the western part of the state at the Mountain Horticultural Crops Research Station, Mills River. This planting was initiated in 2001 with 15 cultivars planted and another eight planted in 2002 with primarily NC cultivars and selections, and included both white and yellow fleshed cultivars and several peento selections. This research has shown that peach production can be accomplished in the mountains of NC and there are commercial orchards being established. Spring freezing temperatures in 2007 resulted in no crop with production in all other years with varying levels of cropping depending on the cultivar. Spring frost/freeze events are a potential threat to many of the earlier blooming cultivars in many years. This is reflected in the cumulative yields through 2011. This research is identifying NCSU developed cultivars that will crop consistently over the long term that will be the most profitable for growers such as Challenger, Intrepid, Contender and China Pearl which had a greater yield per tree than lower chilling cultivars such as Carolina Belle, Winblo and Biscoe. Sporadic tree decline has also been an issue in this planting and trials are underway using laboratory PCR analysis to determine what pathogens may be involved in this tree death.

Publications

  • Parker, M.L., D.F. Ritchie, and G.L. Reighard. 2011. Guardian peach rootstock performance and preplant soil fumigation effects in a fallow site. Acta Hort. 903:469-473.
  • McArtney, S., M. Parker, J. Obermiller and T. Hoyt. 2011. Effects of 1-methylcyclopropene on firmness loss and the development of rots in apple fruit kept in farm markets or at elevated temperatures. HortTechnology 21:494-499.


Progress 10/01/09 to 09/30/10

Outputs
OUTPUTS: The peach rootstock, Guardian, is reported to be tolerant to both root-knot and ring nematodes. Ring nematodes contribute to the incidence of peach tree short life (PTSL), a limiting factor to peach production in the sandier soils of the Southeastern United States. In 2001 a long-term study was established in North Carolina at the Sandhills Research Station in Jackson Springs to evaluate the performance of Guardian compared to Lovell, the commercial standard, in a site that had been out of peaches and cover cropped for more than five years. Lovell was used as the commercial standard and five selections that are components of the bulk Guardian seedlot were used. One half of each replicate had the soil preplant fumigated with Telone II. The cultivars used in this study were Intrepid, Challenger, Contender and China Pearl. In 2008, the eighth growing season, the trees on Guardian had a greater survival than trees on Lovell for all of the cultivars except Contender. For Intrepid, Challenger, and China Pearl, survival ranged from 15-42% for trees on Lovell compared to 77-94% for trees on Guardian. Through 2008, cumulative yields were numerically greater for trees on Guardian compared to trees on Lovell. Trees grown in fumigated soil had numerically greater TCSA and cumulative yield than trees grown in non-fumigated soil. The experiment with Contender and China Pearl was discontinued after the 2008 season due to excessive tree loss. In 2009, tree survival across fumigation was lowest for trees on Lovell for both Challenger and Intrepid, 21% and 0%, respectively. Trees grown in fumigated soil had numerically greater 2009 and cumulative yields than trees grown in non-fumigated soil. At the end of the 2009 season the experiment with Intrepid was removed due to loss of trees on the Lovell rootstock and at the end of 2010 the experiment with Challenger was removed. This project also encompasses a large scale peach planting in the western region of NC at the Mountain Horticultural Crops Research Station, Mills River. This planting was initiated in 2001 with 15 cultivars planted and another eight planted in 2002 with primarily NC cultivars and selections, and included both white and yellow fleshed cultivars and several peento selections. Spring freezing temperatures in 2007 resulted in no crop with production in all other years with varying levels of cropping depending on the cultivar. Spring frost/freeze events are a potential threat to many of the earlier blooming cultivars in many years. This is reflected in the cumulative yields through 2010. The North Carolina State University developed cultivars with a higher chilling requirement such as Challenger, Intrepid, Contender and China Pearl had a greater yield per tree than lower chilling cultivars such as Carolina Belle, Winblo and Biscoe. PARTICIPANTS: Participants: Individuals: Dr. David Ritchie, Plant Pathology Collaborator, Mr. Tom Hoyt - Research Technician responsible for data collection and daily operations and Ms. Bernadette Clark - Research Technician responsible for data collection and analysis TARGET AUDIENCES: The research for this project is conducted at the Sandhills Research Station, Jackson Springs and the Mountain Horticultural Crops Research Station (MHCRS), Mills River, NC. Data and information generated from these trials are presented at grower meetings and the research is being conducted to benefit commercial growers, county extension agents and enthusiasts. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.

Impacts
Peach tree short life (PTSL) is one of the limiting factors in commercial peach production in the sandier soils of North Carolina. This research has lead to the current recommendations in the Sandhills region that when planting peach trees in PTSL prone sites that Guardian rootstock and preplant fumigation must be used to minimize the potential for PTSL and increase orchard productivity and profitability. In addition, even in soils that have been fallow for more than five years, data indicate that greater yields and tree survival are achieved with preplant fumigation and the use of the Guardian rootstock. This research has also shown that peach production can be accomplished in the mountains of NC and there are commercial orchards being established. This research is identifying NCSU cultivars that will crop consistently over the long term that will be the most profitable for growers.

Publications

  • No publications reported this period


Progress 10/01/08 to 09/30/09

Outputs
OUTPUTS: The peach rootstock, Guardian, is reported to be tolerant to both root-knot and ring nematodes. Ring nematodes contribute to the incidence of peach tree short life (PTSL), a limiting factor to peach production in the Southeastern United States. In 2001 a long-term study was established in North Carolina at the Sandhills Research Station in Jackson Springs to evaluate the performance of Guardian compared to Lovell, the commercial standard, in a site that had been out of peaches and cover cropped for more than five years. Lovell was used as the commercial standard and five selections that are components of the bulk Guardian seedlot were used. One half of each replicate had the soil preplant fumigated with Telone II. The cultivars used in this study were Intrepid, Challenger, Contender and China Pearl. In 2008, the eighth growing season, the trees on Guardian had a greater survival than trees on Lovell for all of the cultivars except Contender. For Intrepid, Challenger, and China Pearl, survival ranged from 15-42% for trees on Lovell compared to 77-94% for trees on Guardian. Through 2008, cumulative yields were numerically greater for trees on Guardian compared to trees on Lovell. Trees grown in fumigated soil had numerically greater TCSA and cumulative yield than trees grown in non-fumigated soil. The experiment with Contender and China Pearl was discontinued after the 2008 season due to excessive tree loss. In 2009, tree survival across fumigation was lowest for trees on Lovell for both Challenger and Intrepid, 21% and 0%, respectively. Trees grown in fumigated soil had numerically greater 2009 and cumulative yields than trees grown in non-fumigated soil. At the end of the 2009 season the experiment with Intrepid was removed due to loss of trees on the Lovell rootstock. This project also encompasses a large scale peach planting in the western part of the state at the Mountain Horticultural Crops Research Station, Mille River. The planting in the western part of the state initially began with 15 cultivars planted in 2001, with another eight planted in 2002 with primarily NC cultivars, and included both white and yellow fleshed cultivars and several peento selections. Because of Spring freezing temperatures no crop was harvested in 2007 and in 2008 and 2009 there was a frost/freeze event shortly before bloom which affected some of the cultivars. Although only 15-20% of the blossoms are required for a full crop, there was a less than commercial crop on several of the cultivars in 2008 and 2009. Several of the NCSU higher chilling cultivars such as Contender and China Pearl had a significant crop compared to some of the lower chill cultivars such as Carolina Belle and Winblo. PARTICIPANTS: Individuals: --Dr. David Ritchie, Plant Pathology Collaborator --Mr. Tom Hoyt - Research Technician responsible for data collection and daily operations --Ms. Bernadette Clark - Research Technician responsible for data collection and analysis TARGET AUDIENCES: The research for this project is conducted at the Sandhills Research Station, Jackson Springs and the Mountain Horticultural Crops Research Station (MHCRS), Mills River, NC. Data and information generated from these trials are presented at grower meetings and the research is being conducted to benefit commercial growers, county extension agents and enthusiasts. PROJECT MODIFICATIONS: Not relevant to this project.

Impacts
Peach tree short life (PTSL) is one of the limiting factors in commercial peach production in the sandier soils of eastern North Carolina. This research illustrates to peach growers in the southeast when replanting peach trees in PTSL prone sites the importance of using Guardian rootstock and preplant fumigation to minimize the potential for PTSL and increase orchard productivity and profitability. In addition, even in soils that have been fallow for more than five years, initial data indicate that greater yields and tree survival are achieved with preplant fumigation and the use of the Guardian rootstock. This research has also shown that peach production can be accomplished in the mountains of NC and there are commercial orchards being established. However, this research is working to identify cultivars that will crop consistently over the long term that will be the most profitable for growers.

Publications

  • No publications reported this period


Progress 10/01/07 to 09/30/08

Outputs
OUTPUTS: The peach rootstock, Guardian, is reported to be tolerant to both root-knot and ring nematodes. Ring nematodes contribute to the incidence of peach tree short life (PTSL), a limiting factor to peach production in the Southeastern United States. In 2001 a long-term study was established in North Carolina at the Sandhills Research Station in Jackson Springs to evaluate the performance of Guardian compared to Lovell, the commercial standard, in a site that had been out of peaches and cover cropped for more than five years. Lovell was used as the commercial standard and five selections that are components of the bulk Guardian seedlot were used. One half of each replicate had the soil preplant fumigated with Telone II. The cultivars used in this study were Intrepid, Challenger, Contender and China Pearl. In 2008, the eighth growing season, the trees on Guardian had a greater survival than trees on Lovell for all of the cultivars except Contender. For Intrepid, Challenger, and China Pearl, survival ranged from 15-42% for trees on Lovell compared to 77-94% for trees on Guardian. Through 2008, cumulative yields were numerically greater for trees on Guardian compared to trees on Lovell. Trees grown in fumigated soil had numerically greater TCSA and cumulative yield than trees grown in non-fumigated soil. This project also encompasses a large scale peach planting in the western part of the state at the Mountain Horticultural Crops Research Station, Mille River. The planting in the western part of the state initially began with 15 cultivars planted in 2001, with another eight planted in 2002 with primarily NC cultivars, and included both white and yellow fleshed cultivars and several peento selections. Because of Spring freezing temperatures no crop was harvested in 2007 and in 2008 there was a frost/freeze event shortly before bloom which affected many of the cultivars. Although only 15-20% of the blossoms are required for a full crop, there was a less than commercial crop on several of the cultivars. Several of the NCSU higher chilling cultivars such as Contender and China Pearl had a full crop compared to some of the lower chill cultivars such as Carolina Belle and Winblo. PARTICIPANTS: Individuals: --Dr. Mike Parker - Project leader responsible for research --Dr. David Ritchie - Collaborator and Plant Pathology adviser --Dr. Greg Reighard - Clemson University - Collaborator --Ms. Bernadette Clark - Research Technician responsible for data collection and analysis Partner Organizations: --NC Peach Growers Association TARGET AUDIENCES: The research for this project is conducted at the Sandhills Research Station, Jackson Springs and the Mountain Horticultural Crops Research Station (MHCRS), Mills River, NC. This past summer at the MHCRS the Summer Tour of the International Fruit Tree Association visited the research plots. Those on the tour included commercial growers, industry representatives as well as reporters and were from multiple states as well as one Canadian province. In addition, an Apple and Peach Field Day was held this summer and commercial growers and allied industry representatives were instructed in the current research and results to date. The research being conducted is to benefit commercial growers, county extension agents and enthusiasts. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.

Impacts
Peach tree short life (PTSL) is one of the limiting factors in commercial peach production in the sandier soils of eastern North Carolina. This research illustrates to peach growers in the southeast when replanting peach trees in PTSL prone sites the importance of using Guardian rootstock and preplant fumigation to minimize the potential for PTSL and increase orchard productivity and profitability. In addition, even in soils that have been fallow for more than five years, initial data indicate that greater yields and tree survival are achieved with preplant fumigation and the use of the Guardian rootstock. This research has also shown that peach production can be accomplished in the mountains of NC and there are commercial orchards being established. However, this research is working to identify cultivars that will crop consistently over the long term that will be the most profitable for growers.

Publications

  • McArtney, S., Obermiller, J.D., Schupp, J.R., Parker, M.L., and Edgington, T.P. 2008. Preharvest 1-Methylcyclopropene delays fruit maturity and reduces softening and superficial scald of apples during long-term storage. HortScience 43:366-371.


Progress 10/01/06 to 09/30/07

Outputs
The peach rootstock, Guardian, is reported to be tolerant to both root-knot and ring nematodes. Ring nematodes contribute to the incidence of peach tree short life (PTSL), a limiting factor to peach production in the Southeastern United States. In 2001 a long-term study was established in North Carolina at the Sandhills Research Station in Jackson Springs to evaluate the performance of Guardian, compared to Lovell, the commercial standard in a site that had been out of peaches and cover cropped for more than five years. Lovell was used as the commercial standard and five selections that are components of the bulk Guardian seedlot were used. One half of each replicate had the soil preplant fumigated with Telone II. The cultivars used in this study were Intrepid, Challenger, Contender and China Pearl. In 2007 a significant freeze in April killed the blossoms and no crop was harvested. At the end of the seventh growing season the trees on Guardian had a greater survival than trees on Lovell for all four cultivars. No significant differences in tree survival were observed between trees in the fumigated and non-fumigated soil, although survival was numerically greater in the fumigated soil for the cultivars of Challenger, Intrepid and Contender. Significant tree loss was observed in the Spring of 2007 from PTSL and for the China Pearl cultivar tree loss was approximately 50 percent survival for trees in both the fumigated or non-fumigated soil with the survival of trees on Lovell being 24 percent compared to a survival of 84 percent for trees on Guardian. This project also encompasses a large scale peach planting in the western part of the state at the Mountain Horticultural Crops Research Station, Fletcher. The planting in the western part of the state initially began with 15 cultivars planted in 2001, with another eight planted in 2002 with primarily NC cultivars, and included both white and yellow fleshed cultivars and several peento selections. Because of Spring freezing temperatures no crop was harvested in 2007.

Impacts
Peach tree short life (PTSL) is one of the limiting factors in commercial peach production in the sandier soils of eastern North Carolina. This research illustrates to peach growers in the southeast when replanting peach trees in PTSL prone sites the importance of using Guardian rootstock and preplant fumigation to minimize the potential for PTSL and increase orchard productivity and profitability. In addition, even in soils that have been fallow for more than five years, initial data indicate that greater yields and tree survival are achieved with preplant fumigation and the use of the Guardian rootstock. This research has also shown that peach production can be accomplished in the mountains of NC and there are commercial orchards being established. However, this research is working to identify cultivars that will crop consistently over the long term that will be the most profitable for growers.

Publications

  • No publications reported this period


Progress 10/01/05 to 09/30/06

Outputs
The peach rootstock, Guardian, is reported to be tolerant to both root-knot and ring nematodes. Ring nematodes contribute to the incidence of peach tree short life (PTSL), a limiting factor to peach production in the Southeastern United States. Two studies were initiated in North Carolina at the Sandhills Research Station in Jackson Springs to evaluate the performance of the peach rootstock Guardian, compared to Lovell, the commercial standard. To evaluate the need for preplant soil fumigation with Guardian, the site selected for the first study had a history of poor peach tree survival. In the field selected, six-year-old trees were removed because of tree mortality from PTSL. After tree removal, the new tree rows were placed directly over the rows of the previous planting and one-half of each row was preplant fumigated with Telone II. Half of the trees planted were on Lovell and the other half were on Guardian. The Guardian rootstock was a composite of five selections to evaluate different selections that make up the bulk Guardian line. Redhaven was the scion for both rootstocks in the initial study. Tree survival, trunk-cross sectional area (TCSA) and cumulative yield were significantly greater for trees planted on Guardian compared to those planted on Lovell across the fumigated and non-fumigated soil after 11 years. Trees planted in preplant fumigated soil had greater survival, TCSA and cumulative yield than those trees planted in non-fumigated soil for both Lovell and Guardian. The second phase of this experiment, which was initiated six years after the first study, was similar with the exception that the site did not have a history of poor tree survival and had been out of peaches and cover cropped for more than five years. Lovell was used as the commercial standard and five selections that are components of the bulk Guardian seedlot were used. One half of each replicate was preplant fumigated with Telone II. The cultivars used in this study were Intrepid, Challenger, Contender and China Pearl. At the end of the sixth growing season and fourth crop year trees in the fumigated soil had greater TCSA and cumulative yield than trees in non-fumigated soil. Tree survival in the fumigated soil was numerically greater than trees in non-fumigated soil. Tree TCSA, survival, and cumulative yield (2003-2006) were significantly greater for fumigated Guardian trees than Lovell trees in the non-fumigated soil. In both studies differences in TCSA and cumulative yield among the selections of Guardian were found. This project also encompasses a large scale planting in the western part of the state at the Mountain Horticultural Crops Research Station, Fletcher. The planting in the western part of the state initially began with 15 cultivars planted in 2001, with another eight planted in 2002 with primarily NC cultivars, and included both white and yellow fleshed cultivars and several peento selections. All cultivars cropped well in 2006.

Impacts
Peach tree short life (PTSL) is one of the limiting factors in commercial peach production in the sandier soils of eastern North Carolina. This research illustrates to peach growers in the southeast when replanting peach trees in PTSL prone sites the importance for proper rootstock selection and cultural management required of the site before planting. Even though there are new rootstocks available, this research has shown that in all peach replant sites on light, sandier soils that growers will benefit financially from preplant soil fumigation and selecting Guardian as the rootstock. In addition, even in soils that have been fallow for more than five years, initial data indicate that greater yields are achieved with preplant fumigation. This research has also shown that peach production can be accomplished in the lower mountains of NC and there are commercial orchards being established. However, this research is working to identify cultivars that will crop consistently over the long term that will be the most profitable for growers.

Publications

  • No publications reported this period


Progress 10/01/04 to 09/30/05

Outputs
The peach rootstock, Guardian, is reported to be tolerant to both root-knot and ring nematodes. Ring nematodes contribute to the incidence of peach tree short life (PTSL), a limiting factor to peach production in the Southeastern United States. Two studies were initiated in North Carolina at the Sandhills Research Station in Jackson Springs to evaluate the performance of the peach rootstock Guardian, compared to Lovell, the commercial standard. To evaluate the need for preplant soil fumigation with Guardian, the site selected for the first study had a history of poor peach tree survival. In the field selected, six-year-old trees were removed because of tree mortality from PTSL. After tree removal, the new tree rows were placed directly over the rows of the previous planting and one-half of each row was preplant fumigated with Telone II. Half of the trees planted were on Lovell and the other half were on Guardian. The Guardian rootstocks used in both studies were composed of five selections to evaluate if there was a difference in the performance of the different selections that make up the bulk Guardian line. Redhaven was the scion for both rootstocks. Tree survival, trunk-cross sectional area (TCSA) and cumulative yield were significantly greater for trees planted on Guardian compared to those planted on Lovell across the fumigated and non-fumigated soil after 10 years. Trees planted in preplant fumigated soil had significantly greater survival, TCSA and cumulative yield than those trees planted in non-fumigated soil for both Lovell and Guardian. The second phase of this experiment, which was initiated six years after the first study, was similar with the exception that the site did not have a history of poor tree survival and had been out of peaches and cover cropped for more than five years. Lovell was used as the commercial standard and five selections that are components of the bulk Guardian seedlot were used. One half of each replicate was preplant fumigated with Telone II. The cultivar used in this study was Contender. At the end of the sixth growing season and third crop year trees in the fumigated soil had greater TCSA and cumulative yield. Tree survival was similar in both the fumigated and non-fumigated soil. In both studies significant differences in TCSA and cumulative yield among the selections of Guardian were found. This project also encompasses a large scale planting in the western part of the state at the Mountain Horticultural Crops Research Station, Fletcher. The planting in the western part of the state initially began with 15 cultivars planted in 2001, with another eight planted in 2002 with primarily NC cultivars, and included both white and yellow fleshed cultivars and several peento selections. All cultivars cropped well in 2005.

Impacts
Peach tree short life (PTSL) is one of the limiting factors in commercial peach production in the sandier soils of eastern North Carolina. This research illustrates to peach growers in the southeast when replanting peach trees in PTSL prone sites the importance for proper rootstock selection and cultural management required of the site before planting. Even though there are new rootstocks available, this research has shown that in sites with a high peach tree short life pressure, that growers will benefit financially from preplant soil fumigation and selecting Guardian as the rootstock. In addition, even in soils that have been fallow for more than five years, initial data indicate that greater yields are achieved with preplant fumigation. This research has also shown that peach production can be accomplished in the mountains of NC and there are commercial orchards being established. However, this research is working to identify cultivars that will crop consistently over the long term that will be the most profitable for growers.

Publications

  • No publications reported this period


Progress 10/01/03 to 09/30/04

Outputs
The peach rootstock, Guardian, is reported to be tolerant to both root-knot and ring nematodes. Ring nematodes contribute to the incidence of peach tree short life (PTSL), a limiting factor to peach production in the Southeastern United States. Two studies were initiated in North Carolina to evaluate the performance of the peach rootstock Guardian, compared to Lovell, the commercial standard. To evaluate the need for preplant soil fumigation with Guardian, the site selected for the first study had a history of poor peach tree survival. In the field selected, six-year-old trees were removed because of tree mortality from PTSL. After tree removal, the new tree rows were placed directly over the rows of the previous planting and one-half of each row was preplant fumigated with Telone II. Half of the trees planted were on Lovell and the other half were on Guardian. The Guardian rootstocks used in both studies were composed of five selections to evaluate if there was a difference in the performance of the different selections that make up the bulk Guardian line. Redhaven was the scion for both rootstocks. Tree survival, trunk-cross sectional area (TCSA) and cumulative yield were significantly greater for trees planted on Guardian compared to those planted on Lovell across the fumigated and non-fumigated soil after 10 years. Trees planted in preplant fumigated soil had significantly greater survival, TCSA and cumulative yield than those trees planted in non-fumigated soil for both Lovell and Guardian. The second phase of this experiment, which was initiated six years after the first study, was similar with the exception that the site did not have a history of poor tree survival and had been out of peaches and cover cropped for more than five years. Lovell was used as the commercial standard in addition to five selections of Guardian were used. One half of each replicate was preplant fumigated with Telone II. The cultivar used in this study was Contender. At the end of the fifth growing season, and second crop year, trees in the fumigated soil had greater TCSA and cumulative yield. Tree survival was similar in both the fumigated and non-fumigated soil. In both studies significant differences in TCSA and cumulative yield among the selections of Guardian were found. This project also encompasses a large scale peach planting in the western part of the state at the Mountain Horticultural Crops Research Station, Fletcher. This planting has 22 selections and cultivars planted in 2001 and 2002, primarily NC selections. All selections cropped well in 2004. Large scale commercial research trials also continued evaluating SmartFresh (1-MCP) for small-scale commercial use in apple production. SmartFresh, which blocks the action of ethylene in the apple, is commercially available. However, having a facility in NC that is economically feasible for treatment of the fruit is not available. Trials have been successfully conducted using refrigerated semi-trailers for treatment of the fruit. Treated fruit have shown 3-6 lbs. greater flesh firmness two months after harvest.

Impacts
Peach tree short life (PTSL) is one of the limiting factors in commercial peach production in the sandier soils of eastern North Carolina. This research illustrates to peach growers in the southeast when replanting peach trees in PTSL prone sites the importance of proper rootstock selection and cultural management required before planting. Even though there are new rootstocks available, this research has shown that in sites with high PTSL pressure, that growers will benefit financially from preplant soil fumigation and selecting Guardian as the rootstock. In addition, even in soils that have been fallow for more than five years, initial data indicate that greater yields are achieved with preplant fumigation. This research has also shown that peach production can be accomplished in the mountains of NC and there are commercial orchards being established. However, this research is working to identify cultivars that will crop consistently over the long term that will be the most profitable for growers. This project has also shown apple growers in NC that SmartFresh can be used successfully in smaller scale commercial production. This will allow growers access to higher value markets with a higher quality apple to the consumer, both in the domestic market as well as the export market.

Publications

  • No publications reported this period


Progress 10/01/02 to 09/30/03

Outputs
The peach rootstock Guardian is reported to be tolerant to root-knot and ring nematodes, which contribute to the incidence of peach tree short life (PTSL). In 1994 a study was initiated to evaluate the performance of Guardian, compared to Lovell. Redhaven was the scion for both rootstocks. The site of this study has a history of poor peach tree survival. Six-year-old trees were removed because of tree mortality from PTSL in the Spring 1993. After tree removal, one-half of each existing row was preplant fumigated and trees were replanted over the rows of the previous orchard in February 1994. In 2003 the trunk-cross sectional area (TCSA) and cumulative yield were significantly greater for trees planted on Guardian compared to those planted on Lovell for trees in both the fumigated and nonfumigated soil. Trees planted in fumigated soil had a significantly greater survival rate, TCSA and cumulative yield than those trees planted in nonfumigated soil for both rootstocks. Trees planted on Guardian produced a larger tree than those on Lovell in both the fumigated and nonfumigated soil. For trees planted in both the fumigated and nonfumigated soil, the cumulative yield was greater for Guardian than Lovell. In the Fall of 1996, one-half of the trees began receiving annual postplant nematicide treatments to determine if nematicides are beneficial with Guardian which did not result in an increase in tree survival or yield. In January 2001, a companion planting was established with Challenger, Intrepid, Contender, and China Pearl on Guardian and Lovell to compare the difference in these rootstocks on a site that had been out of peaches for four years to determine long term productivity and cultural care required for commercial production. This project also encompasses a large scale peach planting in the western part of the state at the Mountain Horticultural Crops Research Station, Fletcher. This planting initially began with 15 cultivars planted in 2001, with another eight planted in 2002 with primarily NC cultivars, and included both white and yellow fleshed cultivars. Large scale commercial research trials also continued evaluating SmartFresh (1-MCP) for small-scale commercial use in apple production. SmartFresh, which blocks the action of ethylene in the apple, is commercially available. However, having a facility in NC that is economically feasible for treatment of the fruit is not available. Trials have been successfully conducted using refrigerated semi-trailers for treatment of the fruit. Treated fruit have shown 3-6 lbs. greater flesh firmness two months after harvest.

Impacts
Peach tree short life (PTSL) is one of the limiting factors for commercial peach production in the sandier soils of eastern North Carolina. This research illustrates to peach growers in the southeast when replanting peach trees in PTSL prone sites, the importance of proper rootstock selection and cultural management required of the site before planting. Even though there are new rootstocks available, this research has shown that in sites with a high peach tree short life pressure, that growers will benefit financially from preplant soil fumigation and selecting Guardian as the rootstock. This research has also shown that peach production can be accomplished in the mountains of NC and there are commercial orchards being established. However, this research is working to identify cultivars that will crop consistently over the long term that will be the most profitable for growers. This project has also shown apple growers in NC that SmartFresh can be used successfully in smaller scale commercial apple production. This will allow growers access to higher value markets with a higher quality apple to the consumer, both in the domestic market as well as the export market.

Publications

  • No publications reported this period


Progress 10/01/01 to 09/30/02

Outputs
In 1994 a study was initiated to evaluate the performance of the peach rootstock Guardian, compared to Lovell. Redhaven was the scion for both rootstocks. Guardian is reported to be tolerant to root-knot and ring nematodes, which contribute to the incidence of peach tree short life (PTSL). The site of this study has a history of poor peach tree survival. Six-year-old trees were removed because of tree mortality from PTSL in the Spring 1993. After tree removal, one-half of each existing row was preplant fumigated and trees were replanted over the rows of the previous orchard in February 1994. At the end of the 2002 growing season, trunk-cross sectional area (TCSA) and cumulative yield were significantly greater for trees planted on Guardian compared to those planted on Lovell for trees in both the fumigated and nonfumigated soil. Trees planted in fumigated soil had a significantly greater survival rate, TCSA and cumulative yield than those trees planted in nonfumigated soil for both rootstocks. There were no significant differences in tree survival among the rootstocks within the fumigated or nonfumigated soil, however large differences in numerical survival rates favoring Guardian were recognized, especially in the nonfumigated soil. Trees planted on Guardian produced a larger tree than those on Lovell in both the fumigated or nonfumigated soil. For trees planted in both the fumigated and nonfumigated soil, the cumulative yield was greater for Guardian than Lovell. In the Fall of 1996, one-half of the trees began receiving annual postplant nematicide treatments to determine if nematicides are beneficial with Guardian which did not result in an increase in tree survival or yield. This project also encompasses two large scale plantings of peaches, one in the western part of the state at the Mountain Horticultural Crops Research Station, Fletcher, and the other in the Sandhills, Jackson Springs. The planting in the western part of the state initially began with 15 cultivars planted in 2001, primarily NC cultivars, and included both white and yellow fleshed cultivars. The second study was planted at the Sandhills Research Station, January 2001, and is a large scale planting of Challenger, Intrepid, Contender, and China Pearl to determine long term productivity and cultural care required for commercial production.

Impacts
This research is useful for peach growers in the southeast when replanting peach trees in selecting the rootstock to be used and the cultural management required of the site before planting. Even though there are new rootstocks available, this research has shown that in sites with a high peach tree short life pressure, that growers will benefit financially from preplant soil fumigation and selecting Guardian as the rootstock. Peaches are also being recognized as a potential alternative crop in many areas of North Carolina. However, cultivar selection will be a critical factor in making sure that the peaches crop consistently. This projectis attempting to identify NC cultivars that can be successfully grown in eastern and western NC.

Publications

  • No publications reported this period


Progress 10/01/00 to 09/30/01

Outputs
In 1994 a study was initiated to evaluate the performance of the peach rootstock Guardian, compared to Lovell. Redhaven was the scion for both rootstocks. Guardian is reported to be tolerant to root-knot and ring nematodes,which contribute to the incidence of peach tree short life (PTSL). The site of this study has a history of poor peach tree survival. Six-year-old trees were removed because of tree mortality from PTSL in the Spring 1993. After tree removal, one-half of each existing row was preplant fumigated and trees were replanted over the rows of the previous orchard in February 1994. At the end of the 2001 growing season, tree survival, trunk-cross sectional area (TCSA) and cumulative yield were significantly greater for trees planted on Guardian compared to those planted on Lovell for trees in both the fumigated and nonfumigated soil. Trees planted in fumigated soil had a significantly greater survival rate, TCSA and cumulative yield than those trees planted in nonfumigated soil for both rootstocks. There were no significant differences in tree survival among the rootstocks within the fumigated or nonfumigated soil, however large differences in numerical survival rates favoring Guradian were recognized. Trees planted on Guardian produced a larger tree than those on Lovell in both the fumigated or nonfumigated soil. For trees planted in nonfumigated soil, the cumulative yield was greater for Guardian than Lovell. For trees planted in fumigated soil, trees on Guardian had greater yields than trees planted on Lovell. In the Fall of 1996, one-half of the trees began receiving annual postplant nematicide treatments to determine if nematicides are beneficial with Guardian. Although in the preliminary stages, it appears that the application of a post-plant nematicide in this PTSL site did not result in an increase in tree survival or yield. This project also encompases two large scale plantings of peaches, one in the western part of the state at the Mountain Horticultural Crops Research Station, Fletcher, and the other in the Sandhills, Jackson Springs. The planting in the western part of the state initially began with 15 cultivars planted in 2001, primarily NC cultivars, and included both white and yellow fleshed cultivars. The second study was planted at the Sandhills Research Station, January 2001, and is a large scale planting of Challenger, Intrepid, Contender, and China Pearl to determine long term productivity and cultural care required for commercial production. Trials also continued with evaluating the growth regulator, MCP, for use in commercial peach production. MCP showed some benefit in increasing peach flesh firmness for some cultivars but needs to be evaluated further to determine if there is a commercial potential for this product.

Impacts
This research is useful for peach growers in the southeast when replanting peach trees in selecting the rootstock to be used and the cultural management required of the site before planting. Even though there are new rootstocks available, this research has shown that in sites with a high peach tree short life pressure, that growers will benefit financially from preplant soil fumigation and selecting Guardian as the rootstock.

Publications

  • No publications reported this period


Progress 01/01/00 to 12/31/00

Outputs
In 1994 a study was initiated to evaluate the performance of the peach rootstock BY520-9 (Guardian TM ), compared to Lovell. 'Redhaven' was the scion for both rootstocks. Guardian is reported to be tolerant to root-knot and ring nematodes, which contribute to the incidence of peach tree short life (PTSL). The site of this study has a history of poor peach tree survival. Six-year-old trees were removed because of tree mortality from PTSL in the Spring 1993. After tree removal, one-half of each existing row was preplant fumigated and trees were replanted over the rows of the previous orchard in February 1994. By the end of the 2000 growing season, tree mortality for the trees planted in unfumigated soil was 46% for Lovell compared to 28% for the trees planted in unfumigated soil for Guardian. However, if the soil was fumigated, mortality was only four and 6% respectively, for Lovell or Guardian. Trunk cross-sectional area for trees grown in the fumigated soil was 71 cm squared compared to 52 cm squared for trees grown in the unfumigated soil for both Guardian and Lovell. The fruit crop in 1996 and 1998 was eliminated from frost/freeze conditions. By the end of the 2000 growing season the trees planted on Lovell in unfumigated soil had a cumulative yield of 40 kg compared to 68 kg for trees in unfumigated soil on Guardian. When both rootstocks were planted on fumigated soil, the cumulative yield was 69 kg and 87 kg respectively, for Lovell or Guardian. In the Fall of 1996, one-half of the trees began receiving annual postplant nematicide treatments to determine if nematicides are beneficial with the Guardian rootstock. Trials also continued with evaluating growth regulators for use in commercial peach production; ReTain, an ethylene biosynthesis inhibitor, and MCP, which blocks the action of ethylene in the peach, were evaluated. Both products showed some benefit in increasing peach flesh firmness but need to be evaluated further for timing and rate refinements.

Impacts
This research is useful for peach growers in the southeast when replanting peach trees in selecting the rootstock to be used and the cultural management required of the site before planting. Even though there are new rootstocks available, this research has shown that in sites with a high peach tree short life pressure, that growers will benefit financially from preplant soil fumigation and selecting BY520-9 as the rootstock.

Publications

  • No publications reported this period


Progress 01/01/99 to 12/31/99

Outputs
In 1994 a study was initiated to evaluate a new peach rootstock, Guardian (BY520-9), compared to the commercial standard of Lovell. Guardian is reported to be tolerant to root-knot nematodes and not affected by ring nematodes, which contribute to the incidence of peach tree short life (PTSL). The site of this study has a history of poor peach tree survival. The Spring prior to planting, trees were removed because of tree mortality from PTSL. After tree removal, one-half of each existing row was preplant fumigated and trees were replanted over the rows of the previous orchard in February, 1994. In the spring of 1999, cumulative tree mortality for the trees planted on Lovell was 22% compared to 15% for the trees planted on Guardian. Trunk cross-sectional area (TCSA) at the end of the fifth growing season for trees on Guardian was slightly larger than trees on Lovell, however, TCSA for trees grown in the fumigated soil was approximately double that of trees grown in the unfumigated soil for both Guardian and Lovell. The fruit crop was eliminated in 1998 due to Spring frost/freeze conditions just prior to full bloom. However, yields in 1999 were not different between Lovell and Guardian, but the yield from the trees in the fumigated soil was double that of trees grown in unfumigated soil. In the Fall of 1996, annual Fall nematicide treatments began on one-half of the trees to determine if such treatments are necessary or beneficial with the Guardian rootstock. At present, no suppression of nematode populations has been observed. A trial with foliar applications of ReTain, a harvest delay growth regulator for apples, was evaluated on peaches. ReTain applications at the rate of 50 g a.i./acre three days before harvest resulted in increased flesh firmness at harvest and decreased ethylene evolution which continued for up to three weeks in cold storage.

Impacts
(N/A)

Publications

  • No publications reported this period


Progress 01/01/98 to 12/31/98

Outputs
In 1994 a study was initiated to evaluate a new peach rootstock, Guardian (BY520-9), compared to the commercial standard of Lovell. Guardian is reported to be tolerant to root-knot nematodes and not affected by ring nematodes, which contribute to the incidence of peach tree short life (PTSL). The site of this study has a history of poor peach tree survival. The Spring prior to planting, trees were removed because of tree mortality from PTSL. After tree removal, one-half of each existing row was preplant fumigated and trees were replanted over the rows of the previous orchard in February, 1994. In the spring of 1998, cumulative tree mortality for the trees planted on Lovell was 38% compared to 15% for the trees planted on Guardian. Trunk cross-sectional area (TCSA) at the end of the fourth growing season for trees on Guardian was slightly larger than trees on Lovell, however, TCSA for trees grown in the fumigated soil was approximately double that of trees grown in the unfumigated soil for both Guardian and Lovell. The fruit crop was eliminated in 1998 due to Spring frost/freeze conditions just prior to full bloom. However, yields in 1997 were not different between Lovell and Guardian, but the yield from the trees in the fumigated soil was double that of trees grown in unfumigated soil. In the Fall of 1996, annual Fall nematicide treatments began on one-half of the trees to determine if such treatments are necessary or beneficial with the Guardian rootstock. At present, no suppression of nematode populations has been observed. A trial with foliar applications of ReTain, a harvest delay growth regulator for apples, was evaluated on peaches. ReTain applications at the rate of 50 g a.i./acre three days before harvest resulted in increased flesh firmness at harvest and decreased ethylene evolution which continued for up to three weeks in cold storage. Further evaluation will be conducted in 1999.

Impacts
(N/A)

Publications

  • Nyczepir, A.P., Bertrand, P.F., Parker, M.L., Meyer, J.R. and Zehr, E.I. 1998. Interplanting wheat is not an effective postplant management tactic for Criconemella xenoplax in peach production. Plant Disease 82(5):573-577.
  • Parker, M.L. 1998. Bloom thinning of peaches with gibberellic acid in the southeast. HortSci. 33(3):514.


Progress 01/01/97 to 12/31/97

Outputs
In 1994 a study was initiated to evaluate a new peach rootstock, Guardian (BY520-9), compared to the commercial standard of Lovell. Guardian is reported to be tolerant to root- knot nematode and not affected by ring nematodes which contribute to the incidence of peach tree short life (PTSL). The site of this study has a history of poor peach tree survival. The Spring prior to planting, trees were removed because of tree mortality from PTSL. After tree removal, one-half of each existing row was pre-plant fumigated and trees were replanted over the rows of the previous orchard in February, 1994. In the spring of 1997, cumulative tree mortality for the trees planted on Lovell was 20% compared to 6% for the trees planted on Guardian. Trunk cross-sectional area (TCSA) at the end of the third growing season for trees on Guardian was no different than trees on Lovell, however, TCSA for trees grown in the fumigated soil was approximately double that of trees grown in the unfumigated soil for both Guardian and Lovell. Yields in 1997 were not different between Lovell and Guardian, but the yield from the trees in the fumigated soils was double that of trees grown in unfumigated soil. In the Fall of 1996 and 1997, one-half of the trees were treated with a post-plant nematicide to determine if such treatments are necessary or beneficial with the Guardian rootstock. Trials with RalexTM, a gibberellic acid, for peach bloom thinning also continued. Ralex was applied in June, 1996 to reduce bloom in the Spring.

Impacts
(N/A)

Publications

  • BLANKENSHIP, S.M., PARKER, M.L. and UNRATH, C.R. 1997. Use of maturity indices for predicting poststorage firmness of 'Fuji'
  • PARKER, M.L., RITCHIE, D. and NYCZEPIR, A. 1997. Peach rootstock Performance of BY520-9 and Lovell in a Peach Tree Short Life Site. HortScience 32(3):497 (Abstract).


Progress 01/01/96 to 12/30/96

Outputs
In 1994 a study was initiated to evaluate a new peach rootstock, GuardianTM (BY520-9), compared to the commercial standard of Lovell. Guardian is reported to be tolerant to root-knot nematode and not affected by ring nematodes which contribute to the incidence of peach tree short life (PTSL). The site of this study has a history of poor peach tree survival. The Spring prior to planting, trees were removed because of tree mortality from PTSL. After tree removal, one-half of each existing row was pre-plant fumigated and trees were replanted over the rows of the previous orchard in February, 1994. In the spring of 1996, tree mortality for the trees planted on Lovell was 30% compared to 10% for the trees planted on GuardianTM. Trunk cross-sectional area at the end of the second growing season for trees grown in the fumigated soil was approximately double that of trees grown in the unfumigated soil for both GuardianTM and Lovell. The 1996 fruit crop was eliminated due to frost/freeze conditions and future yields will be recorded. In the Fall of 1996, one-half of the trees were treated with a post-plant nematicide to determine if such treatments are necessary or beneficial with the GuardianTM rootstock. Trials are also continuing with Release LC(TM), a gibberellin, for peach bloom thinning. Release LC is applied the June prior to the season that thinning is desired. Preliminary results indicate that bloom reduction of up to 40% is achieved with 48 grams applied per acre.

Impacts
(N/A)

Publications

  • PARKER, M.L. and MEYER, J.R. 1996. Peach Tree Vegetative and Root Growth Respondto Orchard Floor Management. HortSci. 31(3)330-333.
  • PARKER, M.L. and YOUNG, E. 1996. High-Density Apple Orchard Management Techniques Evaluated for the Southe.


Progress 01/01/95 to 12/30/95

Outputs
In 1994 a study was initiated to evaluate a new peach rootstock, BY 520-9, compared to the commercial standard of Lovell. BY 520- 9 is reported to be tolerant to root-knot nematode and not affected by ring nematodes which contribute to the incidence of peach tree short life (PTSL). The site of this study was a field where trees were removed because of tree mortality from PTSL, therefore one-half of the field was pre-plant fumigated. Tree productivity, growth and mortality will be measured annually. In the spring of 1995, tree mortality for the trees planted on Lovell was 30% compared to 10% for trees planted on BY 520-9. A peach training system study was established in 1991 to compare higher density training systems to a standard open center tree. Fruit yield for individual trees was greatest for the open center trees and lowest for the perpendicular V trees. However, total yield calculated per unit area was greater for the perpendicular V system compared to the open center system due to increased tree density in the perpendicular V system. Bacterial spot resistance evaluations continued on peach, nectarine and plum variety trials, established in 1991 with 25 peach and nectarine varieties and 35 plum varieties to determine commercial potential in North Carolina.

Impacts
(N/A)

Publications

  • PARKER, M. L. and YOUNG E. 1995. Leader management and soil fumigation affect branching and precocity of young apple trees. HortSci. 30(6):1193-1195.
  • WERNER, D., PARKER, M. L. and WHEELER, E. 1995. Potential relationship between peach tree short life symptomology and aberrant wood anatomy. HortSci. 30(4):786(241) (Abstr.).


Progress 01/01/94 to 12/30/94

Outputs
A study was initiated in 1994 to evaluate and compare a new rootstock, BY 520-9,that is reported to be resistant to root knot nematode and not affected by peach tree short life (PTSL), to the commercial standard of Lovell. One-half of the field was pre-plant fumigated as the trees were planted in a field where trees were removed because of tree mortality resulting from PTSL. Tree productivity, growth and mortality will be measured. A higher density peach training system study, established in 1991, to compare higher density training systems such as central leader, perpendicular V and double perpendicular V to a standard open center tree continued. In 1994, yields on individual trees were greatest for the open center trees and lowest for the perpendicular V trees. However, when total yield was calculated per unit area for the different systems, yields were 53% greater for the perpendicular V system compared to the open center system due to greater tree density in the perpendicular V system. Peach, nectarine and plum variety trials, established in 1991, also continued with 25 peach and nectarine varieties and 35 plum varieties to determine commercial potential and bacterial spot resistance in North Carolina.

Impacts
(N/A)

Publications

  • NO PUBLICATIONS REPORTED THIS PERIOD.


Progress 01/01/93 to 12/30/93

Outputs
Higher density peach training systems which were established in 1991 comparing central leader, perpendicular V, double perpendicular V, and open center are being maintained. Fruit yield, tree growth, and survival are the primary indicators in comparing the four training systems. A severe hailstorm in 1993 eliminated fruit yield data, the first cropping year. Peach, nectarine, and plum variety trials were also established in 1991 with 25 peach and nectarine varieties and 35 plum varieties to determine commercial potential in North Carolina. Tree growth, productivity, and survival will be indicators used for evaluation. The peach and nectarine crops were destroyed by a severe hailstorm and the plum trees did not crop due to a freeze when the trees were in full bloom. Peach bloom delay as affected by fall Ethephon applications was initiated in the fall of 1991, 1992, and 1993. Four varieties, Pekin, Biscoe, Norman and Winblo, are being evaluated for varietal differences in bloom delay. In the spring of 1993 there appeared to be a delay of 5-7 days depending upon variety. Evaluation of the use of Ethephon on fruit maturity was not determined due to a hailstorm which significantly damaged the fruit.

Impacts
(N/A)

Publications

  • NO PUBLICATIONS REPORTED THIS PERIOD.


Progress 01/01/92 to 12/30/92

Outputs
Peach training systems established in 1991 comparing central leader, perpendicular V, double perpendicular V, and open center are continuing. Tree growth, productivity, and survival will be the primary indicators in comparing the four training systems. Peach, nectarine, and plum variety trials also were established in 1991 with 25 peach and nectarine varieties and 35 plum varieties to determine commercial potential in North Carolina. Tree growth, productivity, and survival will be indicators used for evaluation. Peach bloom delay as affected by fall Ethephon applications was initiated in October, 1991 and again in October, 1992. Four varieties are being evaluated for varietal differences in bloom delay. In the spring of 1992, Ethephon treatment appeared to cause a bloom delay of 3-5 days depending upon variety, however further evaluation is needed to determine the benefit and reliability of this treatment.

Impacts
(N/A)

Publications

  • NO PUBLICATIONS REPORTED THIS PERIOD.


Progress 01/01/91 to 12/30/91

Outputs
Plots were established to compare four peach training systems: central leader, perpendicular V, double perpendicular V, and open center. Trees were planted in February 1991 and the training systems were imposed during the summer of 1991. Tree growth, productivity, and survival will be the primary indicators in comparing the four training systems. Peach, nectarine and plum variety trials were established in February 1991 with 25 peach and nectarine varieties and 35 plum varieties to determine commercial potential in North Carolina. Tree growth, productivity, and survival will be indicators used for evaluation. Peach bloom delay as affected by fall ethephon applications was initiated in October 1991. Four peach varieties and two stages of defoliation at application are being investigated.

Impacts
(N/A)

Publications

  • NO PUBLICATIONS REPORTED THIS PERIOD.