Effect of Irrigation Regimes on Yield, Yield Components and Seed Quality of Different Pinto Bean (Phaseolus vulgaris) Genotypes

Identification of drought-resistant genotypes is crucial in order to reduce the negative effects of drought, as one of the most important limiting factors of crop production in arid and semiarid regions. Thus, effects of three irrigation regimes (irrigation after 50 (I1), 100 (I2) and 150 (I3) mm evaporation from a class A pan), as the main plot were investigated. These effects were studied on some morphological traits, yield, yield components and seed quality of ten pinto bean cultivars (KS-21193, KS-21191, KS-21189, E10, E9, Sadri, Talash, local masses Khomein, Eghlid and Fereidoonshahr), as the sub-plot. The experiment was conducted with 3 replications as split-plot based on randomized complete block design in Fereidoonshahr, Esfahan, Iran. Drought stress led to decreases in day to physiological maturity, plant height, pods/plant, seeds/pod, seeds/plant, 100-seeds weight, seed weight/plant, dry matter and grain yield, and harvest index and increases in seed protein percentage. However, only seed protein percentage was not genotype-dependent. Variations of reduction in grain yield from I1 to I2 were observed. These variations were from 54.4% in Sadri to 36.6% in Talash genotype. Also, from I1 to I3 the variations were from 87.3% in KS-21191 to 74.9% in Fereidoonshahr genotype. It could be concluded that while the highest grain yield was obtained in KS-21191 (2319 kg ha-1), probably planting Fereidoonshahr genotype along with irrigation after 150 mm evaporation may lead to moderation of drought stress at regions similar to Fereidounshahr.