Effect of deficit irrigation and fertilization on cucumber
Soil water budgets are essential in determining the proper timing and amount of irrigation. Organic fertilizers can be substituted for commercial fertilizers; however, information is sparse on the interaction of irrigation management and nutrient source on cucumber (Cucumis sativus L.) production. This study evaluated nutrient source and irrigation management on growth and yield of cucumber grown in the arid area of Egypt. A field experiment was conducted using cucumber grown in northern Egypt at Shibin El-Kom in 2006 and 2007 to evaluate water use and fertilizer rate and type. Three irrigation deficits and seven fertilization types were arranged in a randomized split-plot design with irrigation rates as main plots and fertilizer treatments within irrigation rates. Irrigation treatments were a ratio of crop evapotranspiration (ET) as: 1.0 ET, 0.84 ET, and 0.64 ET. Fertilizer treatments were applied at the recommended rate of N either as a commercial fertilizer or with organic manure. Chlorophyll a and b, leaf area index, and yield were greatest with the lowest ratios of male to female flowers when adequate water and high N were used (1.0 ET with chicken manure at 7 Mg/ha). Seasonal water use was 498 and 471 mm for 1.0 ET in 2006 and 2007 plantings over the 125 d growing season, respectively. The yield reduction coefficient averaged 0.77. An optimal scheduling was statistically developed based on crop response in deficit irrigation to achieve maximum yield for different uniformity coefficient variation values. Cucumber performance was significantly affected by both irrigation and nutrient deficiencies.