Location: Crop Improvement and Genetics Research
Project Number: 2030-21430-014-009-S
Project Type: Non-Assistance Cooperative Agreement
Start Date: Sep 1, 2022
End Date: Aug 31, 2024
The objectives of this cooperative research project are to: 1) Clarify the mechanism of two Aegilops tauschii-derived genes for resistance to Hessian fly and other insects in wheat, 2) Determine the mechanism of the two genes for promoting grain yield in wheat, and 3) identify the unknown gene interacted with one of the two insect resistance genes for causing hybrid lethality and reveal the biological interaction.
We previously identified a pair of two closely linked Hessian fly immunity genes, temporarily designated as HA and HB, in goatgrass species Aegilops tauschii, the D-genome progenitor of bread wheat. Both genes have been introduced into bread wheat variety ‘Fielder’ by using Agrobacterium-mediated transformation. We also developed three near-isogenic lines (NILs) Newton-A, Newton-B, and Newton-AB, which carry HA, HB, and HA+HB, respectively, in the background of wheat variety ‘Newton’. To determine if the two genes have resistance to other insects, three NILs (Newton-A, Newton-B, and Newton-AB) and transgenic lines Fielder-A and Fielder-B containing the HA and HB, respectively, will be evaluated for their responses to greenbug, bird cherry-oat aphid, and wheat thrips. To clarify their resistance mechanism, we will perform RNA-seq transcriptome analysis using Hessian fly-infested NILs (Newton-A, Newton-B, and Newton-AB) and transgenic lines Fielder-A and Fielder-B, along with their uninfested control wheat tissue over a time course of 1, 3, 5 and 8 days after hatch (DAH) of Hessian fly eggs. We will identify differentially expressed genes (DEGs) and biological pathways triggered downstream by these H genes and validate 10 upregulated and 10 downregulated candidate DEGs showing 2-fold or greater up or down-regulation using quantitative real time-PCR (qRT-PCR). The DEGs and biological pathways related to yield increase will also be identified through RNA-seq transcriptome analyses using the plant tissues from the three NILs and two transgenic lines along with their controls (Newton and Fielder) at different developing stages.