2007 Annual Report
1a.Objectives (from AD-416)
The objective of the Western Integrated Cropping Systems Research Unit is to develop new materials and methods for sustainable production of high quality cotton and other crops grown in the irrigated western United States. Specifically, research on integrated management of insects, identification and management of invasive plant pathogens and development of novel germplasm should enable efficient and profitable crop production with limited impact on the environment.
1b.Approach (from AD-416)
An interdisciplinary team consisting of an entomologist, geneticist, ecologist and plant pathologist will work together with Federal, State, and University collaborators to solve the major problems facing sustainable production of irrigated crops in the context of environmental stewardship. Efforts focus on discovering and developing new pest insect controls based on parasites and pathogens that impact only pest insects. Determination of overwintering locations and movement of pest insects will allow for more accurate prediction of future pest infestations and to identify release points of parasites. A process for rapid identification of race 4 Fusarium oxysporum vasinfectum (FOV), a disease new to the US will be developed and used to determine the extent of the infestation and to measure plant responses to remediation attempts. Conventional breeding techniques in combination with modern molecular techniques will lead to cotton germplasm with improved yield and fiber qualities and increased resistance to insects and diseases. “Replacing 5303-21220-002-00D (5/05)."
Identification of a commercially available Pima cultivar with resistance to Fusarium wilt race 4. The San Joaquin Valley of California is the primary production region of high-quality Pima cotton in the U.S. Recent identification in the San Joaquin Valley of a new race of Fusarium wilt (FOV race.
4)that is particularly damaging to Pima cotton threatens the sustainability of this industry. Scientists of the Western Integrated Cropping Systems Research Unit in Shafter, CA and University of California - Davis collaborators screened more than 200 varieties of Pima, Acala (a high-quality upland cotton), and Upland cottons for susceptibility to FOV race 4. These efforts identified a commercially available Pima variety (Phytogen 800) with lowered susceptibility to Fusarium wilt. As a result of these screening efforts, planted acreage of Phytogen 800 in the San Joaquin Valley have increased from about 3% before discovery of FOV race 4 to more than 60% at present. Although identification of the Fusarium-tolerance of Phytogen 800 does not solve the FOV race 4 problem in California, use of this variety facilitates continued production of Pima cotton until researchers identify additional sources of resistance or methods to control the disease. This accomplishment contributes to National Program 304 Component 5, Pest Control Technologies, Problem Statement D, Other Biologically-Based Control.
Demonstration of natural infection of cottonseed by Fusarium (FOV) race 4.
The recent discovery of a new and potentially devastating strain of Fusarium wilt (FOV race.
4)infesting cotton in the San Joaquin Valley of California has raised important questions regarding the origin and mechanisms of spread of this disease. While other strains of Fusarium commonly infest cottonseed in other production regions of the U.S., seed infection by FOV race 4 in the San Joaquin Valley would be of particular concern because an estimated 14,000 hectares within the region are devoted to the production of certified planting seed. Efforts by scientists of the Western Integrated Cropping Systems Research Unit to determine the potential for natural infection of acid-delinted seed confirmed a very low rate of Fusarium infection (1 positive/5,000 seeds). This finding was corroborated by a collaborator at the University of California, Davis. Although seed infection rates are apparently low, they are sufficient to pose a threat of infection to producers receiving infected planting seed. These results also emphasize the importance of accurately quantifying the risk posed by infected seed and for developing methods to eliminate or remedy seed infection. This accomplishment contributes to National Program 304 Component 5, Pest Control Technologies, Problem Statement C, Physical/Mechanical and Cultural Control.
5.Significant Activities that Support Special Target Populations
|Number of active CRADAs and MTAs||3|
|Number of web sites managed||1|
|Number of non-peer reviewed presentations and proceedings||6|
Detar, W.R., Penner, J.V. 2007. Airborne remote sensing used to estimate percent canopy cover and to extract canopy temperature from scene temperature in cotton. Transactions of the ASABE, Vol. 50(2):495-506.
Bennett, R.S., Milgroom, M.G., Sainudiin, R., Cunfer, B.M., Bergstrom, G.C. 2007. Relative Contribution of Seed-transmitted Inoculum to Foliar Populations of Phaeosphaeria nodorum. Phytopathology. 97:584-591.
Bancroft, J.S. 2006. Comparison of two species of aphids (homoptera: aphididae) on nine host-plants using age specific fecundity and survival. Southwestern Entomologist. 31:233-243.
Ulloa, M., Brubaker, C., Chee, P. 2007. Cotton. In: Kole, C. (Ed.) Genome Mapping & Molecular Breeding. Vol. 6: Technical Crops. Book Chapter. Springer, Berlin, Heidelberg, New York. p. 1-49.
Ulloa, M., Percy, R.G., Hutmacher, R., Cantrell, R.G. 2006. Registration of SJ-U86 Cotton Germplasm Line with High Yield and Excellent Fiber Quality. Crop Science. 46:2336-2338.
Percy, R.G., May, O.L., Ulloa, M., Cantrell, R.G. 2006. Registration of AGC85, AGC208, and AGC375 upland cotton germplasm lines. Crop Science. p. 1828.
Spurgeon, D.W. 2007. Ecologically-based IPM in cotton. In: Koul, O., Cuperus, G.W., editors. Ecologically-Based Integrated Pest Management. Wallingford, UK: CABI Publishing. p. 367-405.
Spurgeon, D.W., Raulston, J.R. 2006. Boll weevil (Coleoptera: Curculionidae) adult diapause responses to selected environmental and dietary conditions. Annals of the Entomological Society of America. 99:1085-1100.
Suh, C.P., Spurgeon, D.W. 2006. Host-free survival of boll weevils (Coleoptera: Curculionidae) previously fed vegetative-stage regrowth cotton. Journal of Entomological Science. 41:277-284.
Spurgeon, D.W., Suh, C.P. 2007. Diel patterns of pheromone production in the boll weevil (Coleoptera: Curculionidae). Journal of Entomological Science. 42:250-260.