Effects of exogenous application of plant hormones on yield and physiological characteristics of pea under supplemental irrigation

In order to investigate the effect of supplemental irrigations (at flowering, podding, flowering + podding and rainfed as check) and exogenous application of different growth hormones (3 indoleacetic acid [IAA], gibberellic acid [GA3], 6 benzylaminopurine [6 BAP] and distilled water as check), an experiment was conducted at Campus of Agriculture and Natural Resources, Razi University, Kermanshah, Iran. The results showed that the interaction of supplemental irrigation and hormone was significant on green pod yield, biological yield, 100-grains weight, harvest index. The number of pods per plant and grains per pod were influenced by the effects of supplemental irrigation and hormones. The use of supplemental irrigation at two stages (flowering and podding) and the application of hormones (IAA and 6-BAP) led to produce the highest grain yield, biological yield and 100-grains weight. Exogenous application of 6-BAP increased the Fv/Fm (photochemical efficiency of photosystem II), performance index, soluble sugar, soluble protein and leaf relative water content. In general, the supplemental irrigation and exogenous application of growth hormones particularly IAA and 6-BAP, can be suitable to prevent exposure of pea to drought stress during critical stages of flowering and podding and thus increases its economic performance.