Monday, November 13, 2006 - 10:30 AM

Characterization of Chickpea Genotypes for Drought Tolerance.

Aziz ur Rehman1, Tom Warkentin1, Rajendra Malhotra2, and Rosalind Bueckert3. (1) Dept of Plant Sciences, Univ of Saskatchewan, 51 Campus Dr, Saskatoon, SK S7N 5A8, Canada, (2) ICARDA, PO Box 5466, Aleppo, Syria, (3) Department of Plant Sciences, University of Saskatchewan, 51 Campus Drive, Saskatoon, SK S7N 5A8, Canada

Chickpea (Cicer arietinum L.) is an important food legume crop mainly grown under rainfed conditions. Drought is the most important abiotic stress in most of the chickpea growing areas and occasionally severe drought leads to complete crop failure. Studies on drought management in different crops reveal that host tolerance is the best strategy to overcome the stress.  The present study was designed to differentiate a set of drought tolerant and drought susceptible genotypes with respect to root and shoot traits, and to study which relationships, if any, could be used to select drought tolerant cultivars in a breeding program. Eight diverse chickpea genotypes were grown in polyvinyl chloride (PVC) pipes (1.2 x 0.15m) in the greenhouse at the Department of Plant Sciences, University of Saskatchewan, Canada during 2005. Three moisture treatments included well watered, drought starting at the 6-leaf stage, and drought starting at flowering. Roots were collected from 0.2m depth increments at two growth stages, two weeks after flowering and at maturity. Genotypes were characterized for 15 morpho-physiological traits and data were analyzed for their associations. Significant differences were observed among genotypes and genotypes x stress interactions for most of the morpho-physiological traits under varying stress levels. The two sampling dates exhibited non-significant differences and all the genotypes attained their full root growth potential by the first sampling date i.e. two weeks after the initiation of flowering. Root lengths among genotypes varied with the stress levels. Cluster analyses performed on genotypic similarities of the root systems showed two distinct groups of genotypes, drought tolerant (high yielding under stress conditions) and drought susceptible (low yielding under stress conditions). The discriminatory analyses giving details of traits contributing towards high yield under drought conditions will be discussed.