SRAP and ISSR molecular markers-trait associations in sorghum genotypes

Abstract EN

In order to better understand the relationship genotype-phenotype, markertrait associations in 7 sorghum genotypes were studied using a set of 75 DNAbased molecular markers (39 SRAP and 36 ISSR polymorphic markers).

SRAP and ISSR analysis showed similar average of the percentage of polymorphism (%P) which was 51.37 and 53.03%, respectively, as well as the average of polymorphic information content (PIC) which was 0.17 and 0.16, respectively.

Moreover, the means of marker index (MI) were 0.68 and 0.73 for SRAP and ISSR markers, respectively.

The result of di-nucleotide repeat ISSR (UBC-846 belonged to (CA) repeats) primers represented the highest levels of polymorphism of about 70%.

The SRAP primer combinations ME4F-EM10R produced the highest level of %P of 86%, while the primers ME2F-EM8R produced the lowest level of %P of 25%.

Single-marker analysis (SMA) indicated that 4 SRAP markers linked to leaf area/plant, panicle length, 1000-Grain weight and grain yield/plant.

The ISSRs markers; UBC-834.1650bp and UBC-834.1700bp were regarded as candidate markers, linked to leaf area/plant, panicle length, 1000-Grain weight and number of green leaves.

The cluster analysis based on SRAP, ISSR and means of phenotypic data revealed similarity coefficient values ranged from0.685 to 0.847, 0.627 to 0.882, and from 0.878 to 0.978, respectively.

Similarity matrices generated by SRAP markers and ISSR showed a positive but insignificant correlation (r = 0.21, P 0.05)