عنوان مقاله [English]
In order to investigate the effect of planting season and compare the performance of different cultivars of greenhouse cucumbers in water stress conditions, thise experiment was performed as a factorial in a completely randomized design with three replications in the Chahanimeh greenhouse complex located in Zahak city of Sistan and Baluchestan province. The treatments included three cultivars of greenhouse cucumbers in Sistan region (Sina, Baresh and Negin cultivars), three irrigation water levels (100%, 75% and 50% plant water requirements) and two planting seasons (first stage cultivation in the first week of October the second stage in the third week of February). Harvesting was done every four days. The weight and number of fruits, the diameter and length of the cucumber in each plot were carefully measured. For better comparison and analysis, mean time data of 1.5 months after the first harvest were used in both planting seasons. Also, performance and water productivity at the end of both seasons were calculated. The results showed that the effects of planting season, cultivar and irrigation water at the probability level of five and one percent had a significant effect on the measured parameters. The highest value of the measured parameters was obtained in the treatment of 100% of the plant's water requirement, which was not significantly different from the 75% treatment of the plant's water requirement. Yield and productivity of irrigation water in the first season of cultivation were 144.6 ton/ha and 20.4 kg/m3, respectively, which is higher than the second season of cultivation (128.7 ton/ha and 17.3 kg/m3). Different cultivars had different results in the first and second seasons of cultivation. In the first season of cultivation, Sina yield (158.2 ton/ha) was better than other cultivars. In the second season, Baresh cultivar yield (156.4 ton/ha) was better than Sina and Negin. Therefore, according to the obtained results, the amount of water consumption can be reduced by 75% and the saved water can be used in the second season of cultivation. Also, considering that Sina cultivar had better results in the first planting season and Baresh cultivar in the second season, these two cultivars should be used in each season.