Water-yield relations of drip irrigated watermelon in temperate climatic conditions

Abstract

The objective of the study, conducted in Vojvodina a northern part of the Serbia Republic, was to analyse the effect of drip irrigation on yield, evapotranspiration and water productivity of watermelon (Cirullus lanatus Thunb.) grown with plasticulture. Irrigation was scheduled on the basis of water balance method. Daily evapotranspiration was computed using the reference evapotranspiration and crop coefficient. The yield of watermelon in irrigation conditions (37,28 t/ha) was significantly higher compared to non irrigated (9,98 t/ha). Water used on evapotranspiration in irrigation conditions was 398 mm and 117 mm on non-irrigated variant. The crop yield response factor of 1,04 for the whole growing season reveals that relative yield decrease was nearly equal to the rate of evapotranspiration deficit. The values of irrigation water use efficiency and evapotranspiration water use efficiency were 9,93 kg/m3 and 10,29 kg/m3 respectively. The determined results could be used as a good platform for watermelon growers in the region, in terms of improvement of the optimum utilization of irrigation water.

Cilj istraživanja, sprovedenog u Vojvodini, bio je da se analizira efekat navodnjavanja kapanjem na prinos, evapotranspiraciju i produktivnost vode u usevu lubenice (Cirullus lanatus Thunb.), gajene na foliji. Vreme zalivanja je određeno na osnovu vodnog bilansa. Dnevne vrednosti evapotranspiracije su obračunate korišćenjem referentne evapotranspiracije i koeficijenta useva. Prinos lubenice u uslovima navodnjavanja (37,28 t/ha) bio je statistički značajno veći u odnosu na prinos u uslovima bez navodnjavanja (9,98 t/ha). Evapotranspiracija lubenice u uslovima navodnjavanja bila je 398 mm i 117 mm na nenavodnjavanoj varijanti. Obračunata vrednost koeficijenta opadanja prinosa od 1,04 za period vegetacije ukazuje da je relativno smanjenje prinosa bilo skoro jednako relativnom deficitu evapotranspiracije. Efikasnost korišćenja vode navodnjavanjem i evapotranspiracijom iznosila je 9,93 kg/m3 i 10,29 kg/m3, redom. Dobijeni rezultati mogu poslužiti kao dobra osnova za proizvođače lubenice u regionu, u smislu poboljšanja i optimizacije navodnjavanja.