Response of Jatropha curcas L. to water deficits: Yield, water use efficiency and oilseed characteristics

Field experiment was carried out at Enshas Experiment Station; Jatropha was transplanted and treated after the second year of the transplanting by different amounts of water stress, viz. 125%, 100%, 75% and 50% of potential evapotranspiration (ETp). The study aims to ensure the multiple benefits of Jatropha and its suitability under Egyptʹs climate in unused lands under scarce water conditions. The results revealed that the average water consumption rate of Jatropha is 6 L week−1 throughout the growing season, which means that Jatropha can survive and produce full yield with high quality seeds under minimum water requirements compared to other crops. The yield of extracted oil was 28.69, 58.39, 30.17 and 22.15 kg ha−1 at 125%, 100%, 75% and 50% of ETp, respectively. The lowest values of total lipid (oil) (25% and 24.5% of Jatropha seeds) were recorded with Jatropha trees that were irrigated by 125% and 50% of ETp, respectively. On the other hand, the treatment that was irrigated by 100% of ETp (control) recorded the highest value of total oil in the seeds (29.93%). The results also revealed that there are no significant differences among the values of the determined oil characteristics due to different water stress ratios. From the results, it could be concluded that the highest characteristics of Jatropha seed oil were recorded with 100% of ETp. In addition water stress had no significant effect on the fatty acid composition of Jatropha seed oil.