Agri-mat and grass mulch effect on crop biomass yield in sandy loam and loam soils

Abstract

The role of agri-mat mulch as a soil and water conservation technology for improved and sustainable plant production has not been explored. The aim of the study was to investigate the effects of agri-mats and grass mulch on crop biomass yield of maize and spinach under sandy loam and loam soils. The following five mulch treatments were established in two sites (Durban with loam soil and Pretoria with sandy loam soil) during the 2017/18 and 2018/19 planting seasons: (a) full agri-mat mulch cover (100%AG), (b) half agri-mat mulch cover, (c) bare (control), (d) six tons of grass mulch per hectare (6t.GM), and (e) three tons of grass mulch per hectare. Crop growth parameters such as number of leaves, leaf length, plant height, and crop biomass yield were measured in both planting seasons. The results indicate that the crop biomass yield (both spinach and maize) was higher under 100%AG treatment compared to other mulching treatments followed by 6t.GM in the Pretoria site. For the Durban site, the highest crop growth parameters and biomass yield for both spinach and maize was recorded under the 100%AG treatment. The 100%AG treatment produced 33% more spinach biomass yield during the 2018 growing season in Durban compared with the 6t.GM treatment, with no percentage differences in the 2019 growing season. In Pretoria, there was a 20% (2018) and 32% (2019) difference in spinach biomass yield between the highest and second-highest performing treatments. As hypothesized, agri-mats can effectively improve crop biomass yields in semiarid and humid agro-ecological zones with different soil types.