Adaptation and Yield Stability for chickpea genotypes to the Mediterranean basin - Abstract
Abstract In Mediterranean traditional agricultural systems, chickpea (Cicer arietinum L.), the third most important pulse crop in the world, is a spring crop and yield is extremely affected by soil water availability during the reproductive phase. As a consequence, there is a need to develop chickpea germplasm with resistance to drought and other abiotic stresses as high temperatures. Chickpea requires around 150 days from sowing to maturity, the actual duration of the development cycle being water and temperature dependent. Chickpea can be cultivated in the range of mean daily air temperatures of 20-30ºC, but high temperatures can limit production seriously. Similarly, chickpea yield may decrease substantially with increased frequency of drought. The present investigation was carried out to study stability for seed yield and its components in 15 chickpea genetically diverse genotypes (13 from ICARDA, Syria and 2 from INIAV, Elvas, Portugal), using a randomized complete block design. Trials were conducted during three years under rainfed conditions in Portugal and Syria, using a late sowing date to naturally expose the plants to drought and heat stress. Our approach revealed a high variability in the yield response among genotypes and regions. Genotype × Environment interaction (GxE) was observed in all experiments and cross-over GxE interaction between top-yielding and low yielding cultivars showed that greater productive potentials in Portugal. Due to higher and more adequate distribution of rainfall, the yield potential is higher in Portugal than in Syria. In general, genotypes that fasten their development cycle showed higher grain yield, especially in dry years. The three years assays across two sites showed four groups of genotypes: 1) genotypes with high adaptation to distinct environments; 2) genotypes adapted to favourable conditions, but with bad performance under adverse conditions; 3); genotypes with very good adaptation for poor environments and 4) genotypes with no adaptation potential. Two genotypes, ILC 3182 and FLIP03-145C, stand out by their high yield in the two regions and three years, including under water stress conditions.