1Indian Agricultural Research Institute, New Delhi-110 012
2Faculted Agronomia, Universitad del Zulia, Maracaibo, Venezuela.
1Dept. of Plant Breeding, HPKVV, Nauni, Solan (173210) H.P.
*Part of PhD. thesis submitted by the senior author to Post Graduate School, IARI, New Delhi.
The effect of introduction of genes for resistance to downy mildew on chlorophyll a and b, and total free amino acid content was studied in twenty four genotypes which consisted of Tifton 23A and B lines, susceptible to downy mildew and several other resistant near-isogenic lines derived from Tifton 23A along with lines having the same nuclear genotype L110 in three diverse cytoplasms S1, S2 and S3 having field resistance and four resistant hybrids, Direct relationship between these biochemical parameters and downy mildew resistance was not evident. However the role of cytoplasmic divergence and nueleo-cytoplasmic interactions within the background of the S1 cytoplasm for these two biochemical attributes was examined which showed the presence of larger amounts of free amino-acids in B lines than their sterile counterparts.
