Effects of different irrigation programs on the growth, yield, and fruit quality of drip-irrigated melon

A field study was conducted in Ankara, a semi-arid region of Central Anatolia, Turkey, on clay-loamy soils in the vegetation seasons of 2005 and 2006. Kirkagac melon cultivar (Cucumis melo L. cv. Kirkagac) was irrigated by the drip method from transplantation to the beginning of the flowering (ISf), fruit setting (ISfs), ripening (ISr), and harvesting (ISh) periods. Water amounting to 50% (P50), 75% (P75), and 100% (P100) of full irrigation water were applied. Some analyses were carried out regarding the growth, yield, and fruit quality parameters in these irrigation programs. Moreover, the amount of water, the seasonal evapotranspiration, and the water use efficiency having been used were determined for each irrigation program. Carrying on the irrigation during the ripening period furthered shoot growth except P100 application, did not significantly affect fruit yield and the soluble solids content of the fruit flesh. Similar but relatively larger fruit size and heavier weight were found in the treatments of ISr and ISh. Fruit yields in the P75 and P100 applications were found similar, but they were found to be higher than the P50 application. The soluble solids contents and the ratings of sensory characteristics were higher in the P75 application. As a result of this study, with respect to the considerably high yield and fruit quality, it was suggested that irrigation be kept on going until the beginning of fruit setting, not during the ripening period, and the application of 75% of full irrigation water amount (ISr P75) is the most convenient irrigation program. In addition, irrigation water amounting to 319.6-331.1 mm was applied and 427.1-472.6 mm seasonal evapotranspiration and 8.9-9.2 kg m-3 water use efficiency was determined in the (ISr P75) irrigation program.