Plant & Animal Genomes XI Conference Plant & Animal Genomes XI ConferenceJanuary 11-15, 2003
Town & Country Convention Center
San Diego, CA
Poster: Gene Isolation
Kernel texture is the most important trait that determines the end-use quality of wheat. To date the variation in kernel texture in hexaploid wheat is attributed to the structure of the puroindoline genes and their various alleles. In a routine cultivar development nursery, using single kernel characterization system (SKCS), we recognized a unique kernel texture phenotype in F4 family lines, which we called “super soft”. It is interesting to note that these lines has Elytrigia elongata genome in their pedigree. RILs were produced using single seed descent (F6-9 generation). The RILs segregate for normal soft and super soft classes. The objective of this study is to resolve the molecular genetics underlying this trait. Genomic DNA from these lines was used to amplify the Pin-a, Pin-b and the grain softness protein (GSP-1) genes. The nucleotide and amino acids sequences of these genes will be presented compared to the standard soft and hard cultivars. To isolate differentially expressed genes between normal-soft and super-soft lines, total RNA from developing seeds was used for mRNA differential display. Multiple differentially expressed cDNAs were identified, excised and sequenced. These cDNAs will be confirmed by amplifying a larger population of RILs. Degenerate primers were designed from a consensus sequence of the neighboring proteins to GSP-1, were used to amplifying genomic DNA and the cDNAs in search of the gene(s) involved in the existence of this trait. Further, the results of EST-SSRs search for rare alleles associated with this trait will be presented.