Marker Trait Association for Different Chick Pea Genotypes against Pratylenchus thornei and Rhizoctonia bataticola

In this study, the interaction between R. bataticola and P. thornei was examined in relation to plant growth. Inoculation with P. thornei affected plant height and shoot and root weights. R. bataticola showed positive correlations with fresh shoot weight (0.638) and fresh root weight (0.597), and a negative correlation with nematode population (−0.534). Fresh shoot weight was positively correlated with fresh root weight (0.663) and negatively correlated with nematode population (−0.604). The genotypes ICCV 2, JAKI 9218 and GBM 2 were resistant to R. bataticola, whereas ICCV 2, JG 11, JG 12 and JG 14 were resistant to P. thornei and to the combined pathogen treatment. The mean major allele frequency among the markers used for marker–trait association analysis was 0.52. The highest major allele frequency (0.72) was observed for CaM0277, whereas the highest gene diversity was recorded for H2E13 (0.86) and H1H11 (0.85). The highest polymorphic information content (0.85) was reported for H2E13. The highest heterozygosity (1.0) was observed for CaM0881 and TR56. Major allele frequency was negatively correlated with gene diversity (−0.899), heterozygosity (−0.734) and polymorphic information content (PIC; −0.800). Gene diversity was positively correlated with heterozygosity (0.706) and PIC (0.975), while heterozygosity was positively correlated with PIC (0.566). Thus, the diversity measures were positively correlated with one another, whereas major allele frequency was negatively correlated with these measures.