PHENOL REACTION ON SEEDS AND GLUMES IN WHEAT SPECIES AT DIFFERENT LEVELS OF PLOIDY

Abstract

One hundred and thirty two accessions of diploid, tetraploid and hexaploid wheat and its related species were investigated for phenol reaction on seeds and glumes. Diploid species having A genome produced black or dark brown colour on seeds while those belonging to D, S, S1, M, MI , C, U and V genomes gave no phenol reaction. Varied reactions were observed among 4x species containing AABB and UUMM genomes while the species having AAGG genomes showed no reaction. All hexaploid wheats gave positive reaction except one accession each of Triticum aestivum ssp. macha (AABBDD) and T. zhukovskyi (AAAAGG). Variable reaction to phenol at tetraploid and hexaploid level are likely due to allelic variation. The coloration on glumes was different from that of seeds. The glumes of all the einkorn wheats except T. uranu gave variable degree of coloration. As in the case of seeds, the glumes of other diploid species except A genome species gave no reaction. The glumes of tetraploid species gave negative-.eaction, except a few accessions of T. tIlrgidum ssp. dicoccoides and carlhlicum, where variation in coloration was observed. Most of the hexaploid wheats reacted to phenol.The exteritofcolourdevelopmenton seeds differs from thaton glumes, suggesting that the factor(s) governing phenolreaction ofseeds and glumes are different and independent of each other. The gene(s) controlling phenol ruction of seeds and glumes in 4x (AABB) and 6x IAABBDD/AAAAGG) species are contributed by A genome. However, the source Of gene(s) controlling phenol reaction in species having UUMM genome is not known.