Genetic diversity in cassava based on agronomical, physiological and EST-microsatellite markers under moisture stress conditions
2023
Ajeesh, B.R | Koundinya, A.V.V. | Senthilkumar, K.M. | Hegde, Vivek | Pati, Kalidas | Pati, Kalidas
The genetic diversity of 23 cassava accessions was studied using agro-physiological and ExpressedSequence Tags (EST)-Microsatellite markers. The genotypes were classified into six clusters based onagronomical and physiological parameters. Cluster-2 had the highest number of genotypes (10), while clusters-5and 6 had single accession, respectively. The high-yielding and highly drought-tolerant genotype 8S501stood alone in cluster 5. It had high cluster mean values for the majority of the traits. The genotypes presentin cluster-4 & 5 and cluster-1 & 2 were divergent and hybridisation between these two groups may result insuperior genotypes for drought tolerance. The EST-Microsatellites obtained from the drought transcriptomeof cassava showed that the mean number of alleles per locus was 1.81, with an average size of 217.7 bp. Thelocus, MeESSR47 (Thylakoid membrane phosphoprotein 14 kDa, chloroplast precursor, putative), had moreheterozygosity (0.387) and Shannon’s Index (0.575) among all the loci. Cumulatively, these results showedlow polymorphism in the EST regions of cassava DNA. The dendrogram showed 4 clusters based on ESTmicrosatellite diversity. The microsatellite-based cluster classification of genotypes did not follow the diversitybased on agronomical traits under moisture stress conditions. A weak correlation revealed by the Mantel testalso indicated no relation between agronomical and molecular diversity.
显示更多 [+] 显示较少 [-]