Identification of low temperature stabilizing genes, controlling chromosome synapsis or recombination, in short arms of chromosomes from the homoeologous group 5 of Triticum aestivum

Abstract

Plants of common wheat Triticum aestivum var. Chinese Spring, lacking the short arms of homoeologous group 5 chromosomes were subjected to a cold treatment of 10oC, and the chiasma frequency in pollen mother cells in the first meiotic metaphase was recorded. The existence in the short arms of chromosomes 5A and 5B of Ltp genes identical in effect to that described for chromosome SDL is demonstrated. In the absence of chromosome arm 5DS a significant decrease in chiasmata along with only a slight reduction in chromosome pairing was observed after the cold treatment, suggesting the existence in 5DS of a gene partially controlling crossing-over at low temperatures. The results that were obtained allow us to propose the following designations for the genes with a stabilizing effect at low temperature: Ltpl in 5DL, Ltp2 in 5AS, Ltp3 in 5BS and Ltr, low temperature recombination, in 5DS.