EFFECTS OF WATER DEFICIT ON DESERT DATE BALANITES AEGYPTIACA L UNDER FIELD CONDITIONS IN SOUTH EGYPT

摘要

Seedlings of Balanites six years old were treated after the second year of the transplanting byrndifferent amount of water stress, viz : 120% , 90% , 60% and 30% potential evapotranspirationsrn(ETp). Field experiment was carried out at kom Ombo Experimental Station, AswanrnGovernorate, Egypt.rnThe study aims to ensure the multiple benefits of Balanites and its suitability under Egyptrnclimate in unused lands under scarce water conditions. A most useful tree, the fruit of whichrnis edible, oily, and gummy, has been suggested as a source of biofuel. Its ability to performrnunder dry conditions has hardly been investigated. The properties of the plant and its oil havernpersuaded investor and policy makers to consider Balanites as substitute for fossil fuels tornreduce greenhouse gas emissions.rnThe results revealed that the average water consumption rate Balanites plants is 7L week -1rnthroughout the growing season , which means that Balanites can survive and produce fullrnyield with high quality seeds under minimum water requirements compared to other plants.rnDrought significantly reduced leaf area, biomass and relative growth rate, but had no effectrnon leaf water content and transpiration efficiency. For all treatments, vegetative growthsrnwere markedly decreased by climatic conditions (high air temperature and high light intensity)rnduring the summer period (June to August). At active growth phase (in spring and autumn),rnsignificant re-increase in all parameters was observed. The yield of extracted oil was 30.6,rn48.3, 32.2 and 24.5 kg/ha-1 at 120 %, 90 %, 60% and 30% of ETp, respectively. In addition,rnwater stress had no significant effect on the saponin composition of Balanites seeds.