Searching chromosomal landmarks in Indian lentils through EMA-based Giemsa staining method

Lentil is one of the oldest protein-rich food crop with only one cultivated and six wild species. India is one important cultivator, producer and consumer of lentils and possesses a large number of germplasms. All species of lentil show 2n = 14 chromosomes. The primary objective of the present paper is to search chromosomal landmarks through enzymatic maceration and air drying (EMA)-based Giemsa staining method in five Indian lentil species not reported elsewhere at a time. Additionally, gametic chromosome analysis, tendril formation and seed morphology have been studied to ascertain interspecific relationships in lentils. Chromosome analysis in Lens culinaris, Lens orientalis and Lens odemensis revealed that they contain intercalary sat chromosome and similar karyotypic formula, while Lens nigricans and Lens lamottei showed presence of terminal sat chromosomes not reported earlier. This distinct morphological feature in L. nigricans and L. lamottei may be considered as chromosomal landmark. Meiotic analysis showed n = 7 bivalents in L. culinaris, L. nigricans and L. lamottei. No tendril formation was observed in L. culinaris, L. orientalis and L. odemensis while L. nigricans and L. lamottei developed very prominent tendrils. Based on chromosomal analysis, tendril formation and seed morphology, the five lentil species can be separated into two distinct groups. The outcome of this research may enrich conventional and biotechnological breeding programmes in lentil and may facilitate an easy and alternative method for identification of interspecific hybrids.