Agricultural Research,Education and Extension Organization Journal of Water Research in Agriculture 2228-7140 31 3 2017 09 23 Evaluation of the Effect of Drought on Germination, Growth, and Fruit Yield of Okra (Abelmoschus esculentus) Evaluation of the Effect of Drought on Germination, Growth, and Fruit Yield of Okra (Abelmoschus esculentus) 377 388 113673 10.22092/jwra.2017.113673 FA H E Associate Professor, Department of Agriculture, Payame Noor University, Tehran, Iran. A A Instructor, Department of Agriculture, Payame Noor University, Tehran, Iran. Journal Article 2017 01 30 This research was carried out to evaluate the effect of drought on germination, growth, and fruit yield of okra in laboratory and field. Laboratory experiment was conducted as a two-factor factorial in agricultural laboratory of Khuzestan Payame Noor University based on completely randomized design in three replications. The first factor was seed priming (including control and seed priming with water and KNO₃) and the second factor was drought stress (matric potentials of -0.3, -0.6, -0.9 and -1.2 MPa). Results indicated that the highest germination percentage was observed under no-stress and hydro priming conditions. Seed germination was decreased with increase in stress, where in control treatment i.e. without hydro priming, increasing drought stress from the first to third level resulted in 72.3 percent reduction in germination percentage. Hydro priming improved seed germination under drought stress and no-stress conditions. The field experiment was carried out during 2015-16 growing season based on RCBD in three replications. The irrigation intervals treatment was based on 70, 100, 130 and 160 mm evaporation from pan. İncreasing irrigation intervals reduced dry matter accumulation, leaf area index, plant height, friut number per plant, and biological and fruit yield of okra. Increasing irrigation interval from the firt level to the second, third, and fourth levels decreased fruit yield up to 9%, 26%, and 31 percent, respectively. Therefore, for optimum yied, okra should experience no drought stress during growth and friut formation. Thus, irrigation after 70 mm evaporation from evaporation pan can be advisable as an irrigation interval for okra. However, since friut yield reduction in the second level of irrigation interval was not considerable and considering economic issues, it may be possible to suggest this irrigation inerval, but it requires more research work.  This research was carried out to evaluate the effect of drought on germination, growth, and fruit yield of okra in laboratory and field. Laboratory experiment was conducted as a two-factor factorial in agricultural laboratory of Khuzestan Payame Noor University based on completely randomized design in three replications. The first factor was seed priming (including control and seed priming with water and KNO₃) and the second factor was drought stress (matric potentials of -0.3, -0.6, -0.9 and -1.2 MPa). Results indicated that the highest germination percentage was observed under no-stress and hydro priming conditions. Seed germination was decreased with increase in stress, where in control treatment i.e. without hydro priming, increasing drought stress from the first to third level resulted in 72.3 percent reduction in germination percentage. Hydro priming improved seed germination under drought stress and no-stress conditions. The field experiment was carried out during 2015-16 growing season based on RCBD in three replications. The irrigation intervals treatment was based on 70, 100, 130 and 160 mm evaporation from pan. İncreasing irrigation intervals reduced dry matter accumulation, leaf area index, plant height, friut number per plant, and biological and fruit yield of okra. Increasing irrigation interval from the firt level to the second, third, and fourth levels decreased fruit yield up to 9%, 26%, and 31 percent, respectively. Therefore, for optimum yied, okra should experience no drought stress during growth and friut formation. Thus, irrigation after 70 mm evaporation from evaporation pan can be advisable as an irrigation interval for okra. However, since friut yield reduction in the second level of irrigation interval was not considerable and considering economic issues, it may be possible to suggest this irrigation inerval, but it requires more research work.  https://wra.areeo.ac.ir/article_113673_3a7231f9426ece4ec72ad3f9299b7b85.pdf