title: Inferring Phylogenetic Relationships of Indian Citron (Citrus medica L.) based on rbcL and matK Sequences of Chloroplast DNA.
abstract: Phylogenetic relationships of Indian Citron (Citrus medica L.) with other important Citrus species have been inferred through sequence analyses of rbcL and matK gene region of chloroplast DNA. The study was based on 23 accessions of Citrus genotypes representing 15 taxa of Indian Citrus, collected from wild, semi-wild, and domesticated stocks. The phylogeny was inferred using the maximum parsimony (MP) and neighbor-joining (NJ) methods. Both MP and NJ trees separated all the 23 accessions of Citrus into five distinct clusters. The chloroplast DNA (cpDNA) analysis based on rbcL and matK sequence data carried out in Indian taxa of Citrus was useful in differentiating all the true species and species/varieties of probable hybrid origin in distinct clusters or groups. Sequence analysis based on rbcL and matK gene provided unambiguous identification and disposition of true species like C. maxima, C. medica, C. reticulata, and related hybrids/cultivars. The separation of C. maxima, C. medica, and C. reticulata in distinct clusters or sub-clusters supports their distinctiveness as the basic species of edible Citrus. However, the cpDNA sequence analysis of rbcL and matK gene could not find any clear cut differentiation between subgenera Citrus and Papeda as proposed in Swingle's system of classification.
authors.affiliation: Indian Agricultural Research Institute, Pusa Campus, New Delhi, India.
authors.forename: Ajit
authors.initials: A
authors.lastname: Uchoi
authors.affiliation: Tissue Culture and Cryopreservation Unit, National Bureau of Plant Genetic Resources (NBPGR), Pusa Campus, New Delhi, 110 012, India. skm1909@gmail.com.
authors.forename: Surendra Kumar
authors.initials: SK
authors.lastname: Malik
authors.affiliation: Indian Agricultural Research Institute, Pusa Campus, New Delhi, India.
authors.forename: Ravish
authors.initials: R
authors.lastname: Choudhary
authors.affiliation: Rubber Board Office, Paralakhemundi, Gajapati, Odisha, India.
authors.forename: Susheel
authors.initials: S
authors.lastname: Kumar
authors.affiliation: Indian Agricultural Research Institute, Pusa Campus, New Delhi, India.
authors.forename: M R
authors.initials: MR
authors.lastname: Rohini
authors.affiliation: Indian Agricultural Research Institute, Pusa Campus, New Delhi, India.
authors.forename: Digvender
authors.initials: D
authors.lastname: Pal
authors.affiliation: Faculty of Agriculture, Department of Horticulture, Ataturk University, Erzurum, Turkey.
authors.forename: Sezai
authors.initials: S
authors.lastname: Ercisli
authors.affiliation: Tissue Culture and Cryopreservation Unit, National Bureau of Plant Genetic Resources (NBPGR), Pusa Campus, New Delhi, 110 012, India.
authors.forename: Rekha
authors.initials: R
authors.lastname: Chaudhury
mesh_terms: D002736:Chloroplasts / Q000235:genetics*; D002957:Citrus / Q000145:classification* / Q000235:genetics*; D018742:DNA, Chloroplast / Q000235:genetics; D019143:Evolution, Molecular; D014644:Genetic Variation; D005838:Genotype; D010802:Phylogeny; D017422:Sequence Analysis, DNA / Q000379:methods*
chemical_list: D018742:DNA, Chloroplast
keywords: Citrus; Maximum parsimony; Neighbor-joining; Phylogeny; cpDNA; matK; rbcL