Genetic diversity and distribution of cucumber (Cucumis sativus L.) landraces in India: A study using DIVA-GIS approach

Abstract

DIVA-GIS, a Geographical Information System is designed to assist the plant genetic resources and biodiversity communities to map the range of distribution of species in which they are interested. The regions where diverse accessions occur could be found by analysing the geographical diversity distribution. In the present study, 50 landraces of cucumber procured from ICAR-NBPGR, New Delhi was evaluated for six yield contributing traits in Augmented Block Design. To study the diversity and distribution of germplasm, geo-referenced points of the collection sites of the genotypes and the agromorphological data recorded were supplemented to shape files and map geo-referenced points using DIVA-GIS software. A wide range of variability was observed for the quantitative traits studied, as evidenced by the wide range of SDI for days to first harvest (0-0.350 to 1.356-2.000) to fruit length (0-0.450 to 1.840-3.000). Highest yield per plant was observed in IC613477 (2205.29 g), a collection from West Bengal and lowest in IC331627 (94.53 g), from Uttarakhand, with an overall mean of 1189.03 g. High SDI of 1.73 to 3.00 was recorded for accessions collected from Andaman and Nicobar Islands, Tripura and Uttarakhand for yield per plant. Collections from West Bengal, Tripura and Mizoram possessed diversity for days to first harvest, fruit weight, fruit diameter and yield per plant, as indicated by the appearance of red grids in these states for these characters. Hence, future germplasm collections can be targeted from these diversity rich states and adjoining areas.