Characterization of the genetic diversity of Citrus species of Nepal using simple sequence repeat (SSR) markers

Nepal has very low Citrus fruit production compared to other countries, which is due to lack of elite varieties and cultivars having desirable traits. Therefore, breeding of elite cultivars is crucial to address ever increasing market demand of citrus fruits in Nepal. Genetic diversity characterization of Citrus germplasm at molecular level is important and crucial step for their utilization in breeding and conservation. In the present investiga-tion, we aimed to utilize 12 SSR markers to characterize genetic diversity of forty-five Citrus accessions of Cit-rus collected from National Citrus Research Program (NCRP), Dhankuta and Kathmandu valley. A total of 60 putative alleles were amplified at 12 SSR loci with an average of five alleles per locus. PIC value ranged from 0.497 with primer TAA 27 to 0.802 with primer TAA 41 with an average value of 0.662. Probability of identity (PI) ranged from 0.075 to 0.383 with an average value of 0.143. Observed Heterozygosity (Ho) ranged from 0.460 to 0.794 and Expected Heterozygosity (He) ranged from 0.460 to 0.794. Shannon's Information Index (I) ranged from 0.677 to 1.678. Principal co-ordinate analysis (PCO) revealed the first principal co-ordinate axis accounting 20.35% and second axis accounting 11.43% of the total variation. UPGMA clustering using Jac-card's similarity coefficient grouped 45 accessions into four clusters. The information generated from this investigation will be useful for National Agriculture Genetic Resources Center (Gene bank) of Nepal and other relevant Citrus researchers and breeders for their conservation, Molecular Breeding-based Research & Devel-opment and their sustainable future utilization. (c) 2023 SAAB. Published by Elsevier B.V. All rights reserved.