Evaluation of morphological traits, fluorescent banding and rDNA ITS sequences in cultivated and wild Indian lentils (Lens spp.)

Abstract

Lentil is a traditional nutritionally enriched crop. India is now the second-highest producer and consumer of cultivated lentils. Out of the seven species, only one is cultivated worldwide, and the remaining are wild species, which are considered valuable plant genetic resources for any future plant breeding programmes in this era of climatic changes. Distinct morphological traits, karyotype diversity assisted by fluorescent banding and ribosomal DNA ITS1-5.8S-ITS2 rDNA ITS sequence analyses are compiled in the present study. Fluorescent banding with two contrasting nucleic acid dyes, chromomycin A3 (CMA) and 4′,6-diamidino-2-phenylindole (DAPI), has been used to characterise the lentil karyotypes of two accessions of L.culinaris Medik (cultivated) and five wild species viz. L.orientalis (Boiss.) M. Popo, L.odemensis Ladiz, L.nigricans (Bieb.) Godr, L.lamottei Czefr. and L.ervoides (Brign.) Grande. This method has unravelled the diverse number and locations of GC/AT-specific heterochromatic regions on chromosomes. The present study provided rDNA ITS sequence-based phylogenetic analysis, which revealed the monophyletic origin of the Indian cultivated and wild species of Lens and grouped them into two possible lineages (clades I and II). Furthermore, this study provided in-depth insights on the interspecies correlation and evolutionary trends within the species of Indian lentil. Detailed knowledge of the genomic structures provides information for any valuable crop species. Thus, the correlation of morphological traits with the results of fluorescent chromosome banding and the generation of an unbiased phylogenetic tree based on rDNA sequence analysis in Indian lentil taxa might be useful in lentil crop improvement programmes.