QTL analysis for yield-related traits under water stress at flowering in tropical maize (Zea mays.L)

In the present study 300 doubled haploid lines from six populations were phenotyped with four yield related traits under water stress at flowering. Quantitative trait loci analysis was done for 263 lines which were genotyped successfully based on individual location and combined locations. For the four yield related traits viz., Anthesis silking interval, ear weight, ears per plant and chlorphyll content a total of 48 significant QTLs were detected based on the separate individual location analysis, of which 26 were detected for Hyderabad location data and 22 detected for Aurangabad location data. In the combined analysis there were 18 QTLs detected in which four QTLs found in population group 1(for ASI), four QTLs in population group 2 (one each for ASI and ears per plant and two for ear weight)and 10 QTLS detected in Pooled population analysis (two for ASI, one for chlorophyll content, five for ears per plant and two for ear weight). However, in combined location QTL analysis one common overlapping QTL was identified on chromosome 8 with same interval for ears per plant and ear weight. Meanwhile eight and three major QTLs were identified in individual location and combined location analysis. These genomic regions could be candidate targets for further fine mapping and marker-assisted breeding in maize.