Methodology to establish a composite collection: case study in lentil

Abstract

The International Center for Agricultural Research in the Dry Areas (ICARDA) is participating in a large-scale programme, Subprogram 1 of the Consultative Group on International Agricultural Research (CGIAR) Generation Challenge Program, that aims to explore the genetic diversity of the global germplasm collections held by the CGIAR research centres. This project will identify a ‘composite collection’ of germplasm for individual crops, representing the range of diversity of each crop species and its wild relatives, and characterize each composite set using anonymous molecular markers, mainly simple sequence repeats (SSRs). The overall goal of this project is to study diversity across given genera and identify genes for resistance to biotic and abiotic stresses that can be used in crop improvement programmes. ICARDA was responsible for creating the composite collection for lentil. ICARDA has the global mandate for lentil and houses the largest global collection of this crop with 10,509 accessions. From this collection, a global composite collection of 1000 lentil accessions was established with the aim to represent genetic diversity and the agro-climatological range of lentil. Accessions for the composite collection were compiled from landraces, wild relatives, and elite germplasm and cultivars. The methodology presented here combined classical hierarchical cluster analyses using agronomic traits and two-step cluster analyses using agro-climatological data linked to the geographical coordinates of the accessions' collection sites. Genotyping for 30 SSR loci will be carried out for all 1000 accessions. Plants grown for DNA analysis will be harvested and progeny will be evaluated under field conditions at ICARDA.