1a.Objectives (from AD-416)
The objective of this cooperative research project is to identify genes important in resistance of soybean to the soybean cyst nematode and to develop soybean plants with broad resistance to soybean cyst nematode.
1b.Approach (from AD-416)
Soybean genes expressed during nematode invasion will be identified that may be used to broaden resistance to SCN through soybean transformation or targeted mutations. Virtually nothing is known about the resistance or susceptible response of soybean to SCN. These genes can be over- or under-expressed in soybean roots and challenged with SCN. Genes will be identified that are up regulated during the resistance response using microarrays or genes localized to known SCN resistance quantitative trait loci (QTLs). These up-regulated genes will be over-expressed using strong constitutive promoters or under-expressed using RNA interference. Transgenic roots with altered expression profiles for candidate resistance-associated genes will be challenged with different races of SCN and the resistance profile examined.
Two DNA sequences that control expression of genes (promoters) were cloned from a portion of the soybean genome known to confer resistance to the cyst nematode. The promoters were cloned into a plant transformation vector so that they can be inserted or transformed into an experimental plant to determine the strength and timing of the promoter using a visual marker. The promoter constructs were transformed into the experimental plant Arabidopsis. The transformed Arabidopsis plants containing the promoter constructs will be used for analysis of promoter expression. These promoters may be useful for controlling the expression of genes proven to confer resistance to nematodes, which directly contributes to the parent project goal of broadening resistance. Conference calls and emails are used to monitor and coordinate progress with Ohio State collaborators and the United Soybean Board. One annual meeting is held at a conference sponsored by the United Soybean Board.