Progress 09/01/04 to 08/31/06
Work with novel Bt gene derivatives thought to be potentially active against nematodes continued. Specifically, three different Bt derivatives were cloned into plant transformation vectors and introduced into transgenic plants. Antibodies were also raised against these three Bt proteins. Plant transformation and analysis for nematode resistance is expected to be completed within the coming year. Additional work on nematode resistance genes included the cloning and partial characterization of a collagenase from C. elegans. Collagen is the major structural protein of nematode exoskeletons and there has previously been a great deal of interest in using collagenase enzymes as anti-nematode genes. The diversity of collagen types has been a complicating factor in these past attempts. Collagenases previously examined (such as human) have low activity against nematode collagen which may explain previously disappointing results. Using a bioinformatic approach we determined that
the C. elegans genome contains a collagenase homolog- which makes sense since they need to remodel their exoskeleton as they grow. Characterization of this gene showed that it was indeed expressed as an active gene. A full-length cDNA was cloned and sequenced. Current work includes expression of this gene in E. coli and in-planta for biochemical analysis of its putative collagenase activity and testing it for anti-nematode activity when expressed in transgenic plants. Ongoing work on development of resistance genes for pest transmitted diseases continued with further development of resistance genes for Gemini- and tosopviruses. These are particularly important concerns since there are insufficient natural resistance resources available to protect crops from these viruses and because there are no effective controls for the pests that transmit them. Progress was also made on development of multi-gene expression systems which will allow plant to be engineered with multiple genes
simultaneously. This is a particularly important goal since adding a single pest / disease resistance gene at a time is unlikely to be effective in addressing the multitude of pest / disease problems confronting producers currently. Finally, we continued making progress on applying molecular techniques for accurate pest identification. Often times determining which pest is present is a crucial but difficult descision. Our work during the current year contributed to the development of a molecular diagnostic for fire ants which is capable of differentiating several closely related species that are virtually impossible to differentiate by morphological features. In addition to enabling precision agriculture, definitive tests like this will play an ever more important role as trade, quarantine, and security issues grow in the future.
Crop pests are estimated to cause the loss of up to 40% of the world's crops annually, at an estimated cost of US $200 billion. Advances from this research will reduce the impact of pests and the diseases they spread, thereby increasing agricultural productivity. In addition, the control of pests and the diseases they transmit will improve the sustainability and profitability of agriculture will also be improved by reducing the reliance on chemical pest controls. Environmentally sound control of insect pests through biotechnology will have a tremendous impact long term. In the shorter term, some of the virus resistance genes, particularly those for geminiviruses, are expected to have a profound impact on crop production, particularly since there are currently no effective control measures against this group of viruses in many cropping systems. Additionally, the application of new advances in molecular techniques is leading to the development of improved pest and
pathogen detection systems by our group which will improve agricultural production indirectly by improving pest and pathogen identification and forecasting.
- A.L. Jacobson, D.C. Thompson, S. F. Hanson, and L. Murray. 2006. Establishing guidelines to improve identification of the fire ants, Solenopsis xyloni and S. invicta. Journal of Economic Entomology. 99 (2): 313-322
- C. S. Bundy, P. F. Smith, M. English, D. W. Sutton, and S. F. Hanson. 2006. Strain Distribution of the alfalfa weevil (Coleoptera: Curculionidae) in an intergrade zone. Journal of Economic Entomology, 98 (6): 2028-2032.
Progress 01/01/05 to 12/31/05
During the past year significant progress has been made on several fronts. Significant new developments include: 1) the initiation of work on novel Bt toxin derivatives that may have activity against nematodes, 2) demonstration that a novel class of resistance genes derived through combinatorial chemistry methods are active against pest transmitted diseased in transgenic plants, 3)development of a novel system for analysis of cap-independent translation enhancers, 4) the cloning of a colagenase gene from C. elegans for use in engineering nematode resistant plants and 5) the application of molecular phylogeny techniques in high resolution pest identification in cases where traditional methods are unable to quickly and easily distinguish between different agricultural pests. We have also continued work on ongoing projectcts including our long term work aimed at developing and optimizing technology for the simultaneous delivery of multiple pesticide genes to transgenic
Crop pests are estimated to cause the loss of up to 40% of the world's crops annually, at an estimated cost of US $200 billion. At the same time it is predicted that pesticide sales will rise in the US to $33 billion by the year 2003, about 75% of which will go for agricultural applications. Chemical pesticides are both expensive and also raise concerns regarding contamination of food and environment. The development of alternative methods of plant pest control is crucial to sustainable agriculture, particularly in the desert southwest, where drought conditions can lead to total devastation of crops under attack by plant pests. The purpose of this research is to develop alternative methods for pest control by applying the biotechnologies of genetic engineering, gemomics, and proteomics. These advancing technologies can be complemented with related basic and applied sciences, improvements in overall pest management strategies, and the continuation of appropriate
traditional agricultural practices to provide better approaches for plant pest control. The primary purpose of this project is sustainability of agriculture, particularly in arid and semi-arid regions, through the use of advanced sciences to both protect plants from pest invasion and to protect the earth's ecosystems from further damage by chemical pesticides.
- J. R. Randall, D. W. Sutton, S. Hanson, and J. D. Kemp. 2005. BiP and zein binding tomains within the delta zein protein. Planta 221: 656-666.
- J. E. Allen, I. Kamenova, S. Adkins, S. F. Hanson. 2005. First Report of Hibiscus latent Fort Pierce virus in New Mexico. Online. Plant Health Progress doi:10.1094/PHP-2005-0105-01-HN.