Effect of irrigation scheduling on canopy cover development and crop-water management related parameters of O.ficus-indica under prolonged drought conditions.

Opuntia ficus-indica is gaining scientists’ and policy makers’ interest worldwide as drought tolerant crop adopted to marginal low fertile soils. Few studies were conducted to estimate its water management parameters under different soil-climate conditions. O.ficus-indica was planted in the experimental farm of City of Scientific Research and Technological Applications (SRTA-City, Alexandria, Egypt) under different irrigation scheduling applications. The study aimed to understand the effect of severe water deficit on crop development and water management related parameters. First irrigation scheduling (T1) applied irrigation with fixed amount of water (7.2 m3 ha-1 week-1). The second (T2), was applied when soil water content (SWC) became below 35% of field capacity (Ɵfc) in effective root zone. The third (T3), was conducted when SWC was below 30% of Ɵfc. The results revealed higher yield under T1 than T2 and T3. Water productivity was the lowest in T1 (0.62 kg m-3) and the highest in T3 (18.13 kg m-3). Actual crop evapotranspiration (ETa) was significantly higher in T3 (4.80 mm day-1), than T2 (4.56 mm day-1) and T1 (3.84 mm day-1). No significant difference was found in soil water content, canopy cover, crop coefficient among the applied irrigation scheduling. Average canopy cover was 13.63%, 11.08%, and 10.22% for T1, T2, and T3, respectively indicating early crop development stage. The corresponding crop coefficient (kc) was between 0.19 in T1 to 0.23 in T2 and 0.24 in T3. Further study is recommended to confirm obtained results and estimate ETa and kc under middle and end crop development stages.