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Dr. Vamsi Nalam
Department of Biology
Indiana University – Purdue University Fort Wayne
The United States is the world’s largest producer and exporter of soybeans (Glycine max). Soybean production is severely limited by soybean aphid infestation with crop loss estimated at $3.6 - $4.9 billion annually. The current consensus management recommendations that have been developed over more than a decade of research include cultural, genetic, economic and chemical controls. Although these strategies reduce the threat, they do not completely eliminate soybean aphid as a pest. As a complement to current management practices, we propose utilizing a biotechnological approach to enhance plant immunity. The genetic manipulation of components of the plant’s own defense signaling pathways offers an attractive strategy for boosting plant defenses. Regulatory genes that control the expression of multiple defenses are excellent targets for developing broad-spectrum of pathogens. This approach has several important advantages including a minimal impact on crop yield and reduced impact on natural enemies of the aphid due to reduced insecticide sprays. A defense regulatory gene PHYTOALEXIN DEFICINT4 (PAD4) is an excellent candidate for over-expression in soybean plants due to its important role in plant defenses against a broad-spectrum of pathogens. Towards this end, transgenic soybean plants that overexpress the PAD4 gene are currently being developed. The PAD4 transgenic plants are expected to provide a measure of resistance not only against the soybean aphid but also against other important soybean pests.
Biology | Life Sciences
Joshi, Kumud; Selig, Patrick; Saya, Peter M. II; and Nalam, Vamsi J., "Engineering A Host Defense Regulatory Gene, PHYTOALEXIN DEFICIENT4 (PAD4) For Enhancing Resistance to Soybean Aphid" (2015). 2015 IPFW Student Research and Creative Endeavor Symposium. 41.