A study of the association between ISSR and RAPD markers and some agronomic traits in barley using a multiple regression analysis

The identification of associations between molecular markers and agronomic traits provides an excellent tool for

indirect selection of traits of interest in a population. In this study, a stepwise regression analysis was used to

estimate associations between inter-simple sequence repeat (ISSR) and random amplified polymorphic DNA

(RAPD) markers with some agronomic traits in barley genotypes. Two-year average values for the measured traits

under rain-fed and irrigation conditions were used for association analyzes. Thirty-one random RAPD and 20 ISSR

primers were used in the study. The results of the stepwise regression analysis revealed significant associations

between the traits and some of the studied loci. For all traits more than one informative marker was detected.

A total of 88 informative markers, including 32 ISSR loci and 56 RAPD loci, were identified under both tested

conditions. OPC4-1050, E17-400, and E19-1100 markers were associated with grain yield, biomass and spike

length, respectively, under both tested conditions. These markers are relatively more reliable than other

identified markers. Among the RAPD primers, special attention should be drawn to primer E17, which produced

the highest number of fragments associated with traits such as biomass, plant height, spike length and number

of seeds per spike, under rain-fed conditions. Moreover, the UBC856 ISSR primer revealed loci associated with

grain yield, plant height and number of sterile spikelets per spike under irrigated conditions.