1a. Objectives (from AD-416):
Develop multiple disease resistant soybean lines through gene discovery and transfer of disease resistance genes into soybean.
1b. Approach (from AD-416):
The overall approach will include the following three steps: 1) determine functionality of candidate genes involved in resistance to sudden death syndrome, Sclerotinia stem rot, brown stem rot, Rhizoctoinia root rot, and charcoal rot diseases using the bean pod mottle virus-based VIGS system, 2) confirm the resistance reaction in soybean using RNAi gene silencing in soybean, and 3) recover transgenic lines of soybean with resistance to multiple diseases of soybean.
3. Progress Report:
Aphid resistance screening was tested in a controlled environmental chamber for different VIGS testing constructs. The first test completed restricted aphid reproduction because of the thimble-size clip-on cage, and a second attempt will use whole-plant cages after inoculation with VIGS constructs and placed in a greenhouse known to be hospitable to aphid colonization. Several diseases caused by fungal pathogens were initially tested on detached leaves including rust (Phakopsora pachyrhizi), charcoal rot (Macrophomina phaseolina) and anthracnose (Colletotrichum spp.) and were functionally demonstrated to be ready for adoption. In the first implementation, plants carrying the same VIGS constructs used in the aphid test were reared, and are being used to check for resistance/susceptibility to soybean rust, charcoal rot, and anthracnose. These experiments were completed and data has yet to be summarized. Bulked seed from several T3 plants transgenics (construct RLK-3 over-expressed) were planted to provide seed for diverse pathogen testing. Genotypes Jack and LD00-3309 were also planted to provide stocks of control seed.