Effects of nitrogen and phosphorus on yield and yield component of watermelon (Citrullus lanatus thunb. Mansf.)

Abstract

Field experiments were conducted in Samaru in the Northern Guinea savanna zone of Nigeria to test the response of ‘Sugarbaby\' Watermelon (Citrullus lanatus (Thunb). Mansf.) to four levels of nitrogen (0. 60,120 and 180kg N/ha). The treatment combinations were laid out in a spilt-plot design with three replications. Nitrogen had positive significant effects on number of leaves and branches/plant, length of vine and the dry weight of vine. Application of 120 and 180kg N/ha increased the fruit sugar content by 58% and 62% respectively, compared with zero application. The total fruit yield (t/ha) was highest at 120kg N/ha and lowest at zero kg N/ha. The dry weight of vine, length of vine and number of branches were significantly improved by P application. The rates of 17kg/ha and 34kg P/ha increased total fruit yield by 32% and 39% respectively when compared to zero application. P application had no appreciable effect on the sugar content of fruit in 1996 but had in 1997 with 34kgP/ha giving the best result. Interactions between N and P on dry weight of vine and total fruit yield were observed to be significant with the combination of N and P at 120kg N/ha and 34kg P/ha giving highest values.

Journal of Applied Chemistry and Agricultural Research Vol. 5 1998: pp. 48-53