Study of genetic diversity and identification of informative molecular markers related to drought tolerance in foxtail millet [Setaria italica (L.) P. Beauv.]

Identification of associated markers with important agricultural traits is one of the most important methods for accelerating the transfer of desirable traits to other genotypes and their tracking. The aim of this research was to study thegenetic diversity and identification of molecular markers related to drought tolerance traits in foxtail millet [Setaria italica (L.) P. Beauv.]genotypes using the AFLP molecular marker.

In this study, 21 genotypes of foxtail millet were studied in three growing seasons (2013, 2014 & 2016). Drought tolerance indices and correlation between them with grain yield and biological yield were calculated. In order to identify molecular markers associated with drought tolerance traits, association analysis was performed by using the Mixed Linear Model (MLM) and 12 primer combinations of AFLP. Also, marker indices and principal components analysis (PCA) were performed using GenAlEx 6.5 software

The primer combinations used in this study generated a total of 443 scorable bands, of which 316 (71%) were polymorphic. The mean of polymorphism information content (PIC) was 0.24, the mean of Shannon index was 0.38, and the mean of Marker index was 6.22. Also, M-CTG/E-ACC, M-CAA/E-ACC and M-CTA/E-AAC were the most efficient combinations in investigating the diversity of genotypes studied. Based on the results of PCA, the first and second components justify 61.13 percent of the changes. The results of this study showed that HARM, GMP, and MP indices were the best indices for differentiation of drought tolerant samples, and M-CAA/E-AAC-14 and M-CTG/E-ACC-283 markers according to Grain yield and M-CTT/E-ACC-264 markers according to biological yield, were related to these indicators.

According to the results of this study, the HARM, GMP and MP indices could be considered as the best indicators for differentiation of drought tolerant foxtail millet samples. Also, molecular markers associated with these indices can be used to evaluate the drought tolerance of other genotypes in future breeding programs.