Foliar silicon fertilization improves physiological parameters and promotes gains in yields in pumpkin (Cucurbita moschata L.)

Abstract

The supply of silicon (Si) via foliar application can mitigate biotic and abiotic stresses, protecting crops against adverse weather conditions. The objective is to evaluate the effect of leaf application of Si on the growth, nutrition, economic analysis, and yield of pumpkin. The experiment was carried out in a greenhouse in a randomized blocks design with five treatments and seven replications. The treatments were doses of Si: 0-control, 378, 756, 1,134, and 1,512 g ha−1 of Si, applied in the form of potassium silicate stabilized with sorbitol. In each treatment, potassium concentrations were balanced in the solution to eliminate the effect of this nutrient. The amounts of silicon applied were divided equally into three sprays throughout the crop cycle. Foliar application of Si promoted gains in Si content and accumulation in the plant and linearly increased the aerial part, fruit, and total dry mass production. Foliar fertilization with silicon promoted linear gains in fruit yield, reaching 9,032.17 kg ha−1 with the highest dose applied (1,512 g ha−1 of Si), in relation to the control treatment, without Si. Foliar fertilization with potassium silicate stabilized with sorbitol is efficient in promoting greater absorption, especially in non-accumulator plants such as pumpkin. With the greater absorption of Si by plants, there is an increase of up to 141% in fruit production, obtaining a maximum differential profit of US$ 4,397 ha−1 with the use of the highest applied dose, of 1,512 g ha−1, under the evaluated conditions of the present study.