Enhancing Sorghum bicolor (L.) grain yield with the use of field edge rainwater harvesting and NPK fertiliser in a dry region of Zimbabwe

Abstract

Background: Farmers in marginalised areas across Africa are mainly resource poor and have limited capacity to procure enough inorganic fertilisers. This contributed immensely towards declining crop productivity causing food insecurity. Soil moisture stress is another key factor which has led to a decline in crop yields across semi-arid areas. This experiment determines the effects of field edge rainwater harvesting and NPK fertiliser microdosing on sorghum grain yields and agronomic nutrient use efficiency of two sorghum varieties (Macia and SV1). Rainwater harvesting techniques was the main plot factor with three levels (tied contour, infiltration pits and standard contour), sorghum variety was used as subplot factor with two levels (Macia and SV1) and NPK fertiliser as sub-sub plot factor with five levels (0, 25, 50, 100 and 150 kg ha −1 ) with all treatments replicated three times. A randomised complete block design arranged in split-plot was used.Results: Phosphorous was significantly increased from 3.32 to 3.52 mg kg −1 with no significant (p > 0.05) increase in total nitrogen and soil organic carbon. Sorghum grain yields were statistically (p < 0.05) influenced by main treatment factors. Tied contour had considerably higher grain yield (861 kg ha −1 ) than infiltration pits and standard contours. Highest grain yield of 909 kg ha −1 was observed from plots applied 150 kg ha −1 NPK fertiliser. Macia variety performed significantly (p < 0.05) higher than SV1. Grain yields show significant (p < 0.05) increase with increasing fertiliser levels.Interaction of tied contour + Macia+ 150 kg ha −1 NPK fertiliser had significant grain yields (1150 kg ha −1 ) compared to other treatments. Treatments applied NPK fertiliser show significant differences (p < 0.05) than unfertilised plots. Agronomic nutrient use efficiencies were significantly higher (p < 0.05) from all treatments applied 25 kg ha −1 NPK fertiliser. Sorghum variety Macia had better nutrient use efficiency than SV1 in 2017/18 and 2018/19 seasons except during 2019/20 where results show insignificant differences.

Tolerance of Two Sorghum Varieties to Salinity Using Different Nutritional Practices and Two Leaching Requirements

“…These results confirm [38] results who found that the increase in soil salinity has led to a decrease in the grain yield of sorghum, as well as the role of fertilization in increasing the grain yield by improving the growth and development of the plant and reducing the negative effects of biotic and abiotic stress on the plant or improving the physical, chemical and Fertile properties of the soil [40, 22, 15, 42 and 41], and the role of Sorghum Variety (C 2 ) which is distinguished by the result from the Sorghum variety (C 1 ) under the experiment current conditions and certain leaching and fertilizing management. Even though the conditions of the current experiment were in saline soil and irrigated with low-quality water, the application of good management practices of fertilizing, leaching requirements, and selection of relatively tolerant varieties can achieve good results and the results of the current study is within the good production levels indicated by [43], where he found that the production rate of sorghum for different varieties is between 3000-6000 Kg ha -1 . As well as production efficiency (Agronomic efficiency) increased about ten times as a result of fertilization with various nutrients.…”

Biobutanol Production Using Non-grain Biomass Sorghum saccharatum as a Substrate

“…An integral indicator that characterizes the efficiency of growing sweet sorghum for energy purposes is the output of biofuel (bioethanol, biogas, solid biofuel) and the output of energy [22,23]. Ethanol is obtained using sweet sorghum juice at an industrial scale [24], and correlative data have been obtained in our study.…”

Microdosing of nitrogen fertiliser and cattle manure under in situ rainwater harvesting to improve maize production in smallholder farming system in a semiarid area of Zimbabwe

“…Poor mechanisation in smallholder farming environments has also contributed to low adoption of soil and water conservation techniques (Hamilton et al, 2022). Related study by Kugedera, Mandumbu, Nyamadzawo, et al (2023) and Swai et al (2023) indicated that most farmers in semiarid areas of Africa are not fully aware about the benefits of soil and water conservation and nutrient management practices.…”

“…Soils in the study area are sandy loam which have low nitrogen (N) content and respond better to application of organic manure combined with mineral fertiliser (Kugedera, Mandumbu, & Nyamadzawo, 2023; Kugedera, Nyamadzawo, & Mandumbu, 2022). Food production continuously declined and remains at subsistence level with many farmers failing to produce enough food for a year (Kugedera, Mandumbu, Nyamadzawo, et al, 2023; Twomlow et al, 2008). Inadequate application of nutrient sources causes many soils to be deficient of major nutrients such as N, potassium (K) and phosphorous (P) and other important micronutrients required by plants (Kihara et al, 2017; Sileshi et al, 2019).…”