1National Research Centre on Plant Biotechnology, IARI, Pusa Campus, New Delhi, 110 012, India.
2Directorate of Sorghum Research, Rajendranagar, Hyderabad, 500 030, India.
3Central Institute for Cotton Research, Nagpur, 440 010, India.
4Division of Genetics, Indian Agricultural Research Institute, New Delhi, 110 012, India.
5Molecular Biology Lab, Department of Genetics and Plant Breeding, CCSU, Meerut, 250 004, India.
*Corresponding author. E-mail: srbhat22@rediffmail.com
Online published 6 April, 2010.
A total 177 simple sequence repeat (SSR) markers were screened using a set of 47 Upland cotton genotypes comprising 14 commercial varieties, 14 germplasm accessions and 19 advanced breeding lines to identify informative markers for genetic diversity assessment and fingerprinting in G. hirsutum. Only 21% (38/177) of SSR markers tested showed polymorphism with a mean of 2.18 alleles per locus and with average polymorphism information content (PIC) of 0.32. The SSR markers revealed a Jaccard's similarity coefficient ranging between 0.43 and 0.89, with an average of 0.67 among accessions. Cluster analysis using unweighted pair group method with arithmetic averages (UPGMA) and principal component analysis (PCA) indicated that majority of the genotypes were very closely related. All the 47 genotypes showed heterozygosity for at least one of the SSR loci. We discovered 19 rare and 6 unique alleles among the tested genotypes of cotton. Fingerprint based on all the 38 loci revealed a probability of identical match by chance of 3.98×10−8. A set of ten SSR markers was identified which could distinguish all the 47 genotypes with a moderate probability of identical match by chance ( = 0.01).
diversity, fingerprinting, Gossypium hirsutum, PCA, simple sequence repeat
