Optimizing application rate of winery solid waste compost for improving the performance of maize (ZEA MAYS L.) grown on Luvisol and Cambisol.

Abstract

The use of winery solid waste compost (WSW) on croplands represents an important strategy for WSW management. However, the full benefits of the use of this compost as an organic fertilizer can be derived with accurate recommendations. Hence, a 4×7×2 factorial experiment was conducted under tunnel house conditions to determine the optimum rates of the WSW compost using quadratic and linear-plus plateau models. The trial comprised of four WSW compost types applied at various rates (0, 5, 10, 20, and 40 t/ha) on two soils (Luvisol and Cambisol). Generally, stem girth, plant height, leaf number per plant, dry matter yield (DMY), and relative agronomic effectiveness (RAE) increased with higher compost rates. The Principal Component Analysis showed that there is a high correlation between the 20 t/ha rate of WSW compost and DMY. The models had comparable R2 values. Optimum rates predicted across the two soils by the linear-plus-plateau model ranged from 11.78 to 26.03 t/ha but from 28.16 to 39.53 t/ha with the quadratic model. Higher compost rate predicted by the quadratic model than the linear-plus plateau model resulted in a marginal increase in DMY with few exceptions. Consequently, the linear-plus-plateau model may be a preferred model when predicting the optimum WSW compost rate for maize. The results showed that the WSW compost at a rate of 20 t/ha can be recommended for maize.