2014
Enhancing disease resistance in soybean through the tools of biotechnology
Category:
Sustainable Production
Keywords:
GeneticsGenomics
Lead Principal Investigator:
Tom Clemente, University of Nebraska at Lincoln
Co-Principal Investigators:
Feng Qu, Ohio Agricultural Research and Development Center
Project Code:
Contributing Organization (Checkoff):
Institution Funded:
Brief Project Summary:

The goals of this research program are to monitor the agronomic performance and stability of a multi-viral resistance phenotype under field environments, and to design and test strategies for controlling soybean aphid predation with the transgenic expression of aphid-targeting interfering RNAs (iRNA).

Unique Keywords:
#alfalfa mosaic virus (amv), #bean pod mottle virus (bpmv), #breeding & genetics, #soybean aphid - genetic resistance, #soybean biotechnology, #soybean genetically engineering, #soybean mosaic virus (smv)
Information And Results
Project Deliverables

Final Project Results

Update:
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We previously produced five different events of transgenic soybean that expressed three short hairpin (sh) RNAs targeting three different genes of soybean aphids. These lines are named as CVI lines based on the aphid genes they were intended to target: C002 (C), a vacuolar ATPase (V), and the translational initiation factor eIF2A (I). Initial tests showed some of the lines exhibited good levels of resistance to aphids.

Our repeat experiments failed to confirm these initial results with acceptable consistency. In addition, expression profiling of the siRNAs produced in the transgenic events was monitored. A substantial decline in siRNA levels from T0 to T1 generation was observed, which may account for the inconsistency in the aphid resistance phenotype. One possible reason could be that unlike previous RNAi constructs, we used a different promoter to drive the expression of the shRNA transcripts.

We assembled four microRNA (miRNA), and different interfering RNA molecule, constructs that target either the aphid C002, or ATPase or combination thereof, each under control of the cassava vein mosaic virus promoter. These constructs were designed by Bin Yu in UNL’s School of Biological Sciences. We produced between 15 to 30 transgenic events per construct. We are systematically phenotyping progeny derived from these events for aphid resistance with assistance from Tiffany Heng-Moss in UNL’s Department of Entomology.

Simultaneously, we are also attempting to identify additional candidate genes of soybean aphids that are susceptible to RNAi-mediated silencing. We used two procedures for this purpose. (i) In collaboration with Drs. Finer and Michel of OSU, we are testing a number of aphid genes using transgenic hairy roots, which can be quickly produced and used for aphid feeding screening; (ii) The Qu lab has developed a new virus vector that can be used to produce aphid-targeting siRNAs in soybean leaves relatively quickly. At the first stage, three different aphid genes are being tested, and the results are expected in next two months.

The United Soybean Research Retention policy will display final reports with the project once completed but working files will be purged after three years. And financial information after seven years. All pertinent information is in the final report or if you want more information, please contact the project lead at your state soybean organization or principal investigator listed on the project.