Phenotypic characterization of crop genetic resources of AA-genome species in rice (Oryza spp.) Mahendran Aswin1,2, Yadav Mahesh C.1,*, Krishnan Gopala S3, Tiwari Shailesh1, Mondal Tapan K.4 1Division of Genomic Resources, ICAR-National Bureau of Plant Genetic Resources, New Delhi, India 2The Graduate School, ICAR-Indian Agricultural Research Institute, New Delhi, India 3Division of Genetics, ICAR-Indian Agricultural Research Institute, New Delhi, India 4ICAR-National Institute of Plant Biotechnology, New Delhi, India *Author For Correspondence: mahesh.yadav1@icar.gov.in
Online Published on 21 February, 2024. Abstract Rice (Oryza sativa L.) is vital for food security of global population especially in Asian countries where more than 90% of the worlds rice is produced and consumed. For exploring variability in morpho-qualitative traits in crop wild relatives (CWRs) for genetic improvement of rice cultivars, we characterized 88 accessions of eight Oryza species of diploid AA-genome utilizing 20 morpho-qualitative traits. High extent of within and between species phenotypic variation was observed for all the morpho-qualitative traits except anther color. Shannon-Weiner’s diversity (H‘ = 0.96) and Pielou’s measure of evenness (J = 0.67) also confirmed the presence of a high level of variability in 19 morpho-qualitative traits for both within and between the Oryza species. The greater diversity (H' >1.00 to 1.39) was recorded for 11 qualitative traits, namely, flag-leaf angle, basal-leaf sheath color, culm angle, panicle type, panicle exsertion, awn color, apiculus color, lemma and palea color, seed shattering, threshability and pericarp color. A moderate level of diversity (H' = 0.50 to 0.99) was observed for leaf-blade pubescence, ligule color, ligule shape, auricle color, stigma color, and lemma and palea pubescence. However, growth habit and awning displayed low level of diversity (H’ < 0.50). Within species variability assessed in 41 accessions of O. nivara and 29 accessions of O. rufipogon revealed existence of higher variability, in O. nivara accessions (H' = 0.87) as compared to O. rufipogon (H’ = 0.69) for most of the traits. Ward’s distance dendrogram grouped the accessions of CWRs into five major clusters, each containing accessions of three to seven species of Oryza AA-genome. Top Keywords AA-genome, Oryza species, Phenotypic characterization, Qualitative traits, Wild rice. Top |