The Contribution of Rye Germplasm Towards Cereal Improvement

Abstract

Alien introgression methodologies have elucidated the usage of distantly or closely related species through intergeneric and interspecific hybridization strategies. Of the various annual and perennial Triticeae species, Secale cereale (2n=2x=14, RR) is one that expresses a well demonstrated potential for cereal improvement with over five million hectares being cultivated to the rye translocation wheats possessing the 1AL/1RS or 1BL/1RS chromosome translocations. We now attribute a 4.3 percent yield advantage to the 1BL/1RS translocation as observed for present analyses of random F-2-derived F-6 lines emerging from the Triticum aestivum cvs. Nacozari/Seri 82 combination. Stringent evaluation of the contribution of 1BL/1RS translocation is anticipated from yield analyses of bread wheat (Seri 82, 1BL/1RS) and durum wheat (Altar 84, 1B) germplasm in which chromosomes 1B or 1BU/1RS respectively have been substituted by eight backcrosses. We have initially inferred that the adverse bread-making quality is not an exclusive function of the 1BL/1RS translocation. The evaluation of the critical genetic substitution stocks produced by backcrossing to Seri 82 will shed further light upon the contribution of 1BL/1RS translocation towards bread making. Additional utilization of rye comes from germplasm exhibiting improved copper efficiency (5AS/5RL or 4BL/5RL), cereal cyst nematode (6BS/6RL) and Karnal bunt resistance (disomic additions 4R and 6R). Transfers and introgressions from these rye sources are being made into some CIMMYT spring wheats. Advanced derivatives from triticale x T. aestivum; with a translocation homozygote; are a source of Septoria tritici resistance. Detection of rye presence has utilized fluorescent in situ hybridization (FISH) as a diagnostic.