Effects of regulated deficit irrigation regime on vegetative and Pomological Characteristics and Yield of oli Olive Amphisis Cultivar.

Background and ObjectivesRegulated deficit irrigation is an optimizing strategy under which crops are allowed to sustain some degree of water deficit and yield reduction. During regulated deficit irrigation the crop is exposed to certain level of water stress either during a particular period or throughout the growing season. The main objective deficit irrigation of is to increase water use efficiency (WUE) of the crop by eliminating irrigations that have little impact on yield, and to improve control of vegetative growth (improve fruit size and quality). The resulting yield reduction may be small compared with the benefits gained through diverting the saved water to irrigate other crops for which water would normally be insufficient under conventional irrigation practices. This study was aimed to investigate the effect of regulated deficit irrigation regime on vegetative and Pomological Characteristics and Yield of oil Olive Amphisis Cultivar in Field Condition.
Materials and methods This experiment was conducted in Dallaho Olive Research Station located in Kermanshah province. An experiment was used based on a randomized complete block design with three replications. Adult oil olive Amphisis cultivar was used. six irrigation regimes including full irrigation (as control), regulated deficit irrigation (100% of full irrigation during growing season plus 25% irrigation during pit hardening, regulated deficit irrigation (100% of full irrigation during growing season plus 75% irrigation from Start pit hardening to Harvesting), regulated deficit irrigation (100% of full irrigation during growing season plus 25% irrigation during fruit verasion), 60% of full irrigation (continuous deficit irrigation) and no irrigation (Rainfed). To elevate the effect of irrigation regimes, some growth vegetative traits measured at the end of growth season including current-season shoot growth and diameter as well as some fruit traits including fruit and oil yield, fruit weight, fruit length and diameter, pulp fresh and dry weight, fruit moisture percent, pulp percent, dry and fresh oil content, Fruit and oil water use efficiency were measured.
Results Obtained results showed that The highest fruit yield, oil yield, fruit weight, fruit diameter, pulp fresh and dry weight, pulp percent were observed at full irrigation and regulated deficit irrigation (100% of full irrigation during growing season plus 25% irrigation during pit hardening and regulated deficit irrigation (100% of full irrigation during growing season plus 25% irrigation during fruit verasion),but the lowest one found at Rainfed. Overall, the results showed that regulated deficit irrigation during fruit pit hardening and fruit verasion could increased water use efficiency, whitout reduce fruit yield, oil yield, fruit weight, fruit diameter, pulp fresh and dry weight.
Discussion In the arid and semi arid as well as sub-tropical regions, water shortage is a normal phenomenon and seriously limits the agricultural potential. Therefore, under irrigation or rain-fed conditions, it is important for the available water to be used in the most efficient way. Regulated deficit irrigation is an optimizing strategy under which crops are allowed to sustain some degree of water deficit and yield reduction. During regulated deficit irrigation the crop is exposed to certain level of water stress either during a particular period or throughout the growing season. The main objective deficit irrigation of is to increase water use efficiency (WUE) of the crop by eliminating irrigations that have little impact on yield, and to improve control of vegetative growth
ConclusionAccording to the results of this research, it can be concluded that that RDI during fruit pit hardening and fruit verasion could increased water use efficiency, whitout reduce fruit yield, oil yield, fruit weight, fruit diameter, pulp fresh and dry weight.