ABSTRACT

The application of insufficient amounts of mineral fertiliser, coupled with unreliable precipitation, has caused a drastic reduction in the yield of sorghum in the smallholder-farming areas of Zimbabwe. This calls for innovative interventions to improve production under changing climatic conditions. This study evaluated the effect of contour-based rainwater-harvesting methods and the use of cattle manure + N nutrient amendment on sorghum yield. A split-split plot experiment was conducted where rainwater-harvesting practice, sorghum variety, cattle manure + N and distance from rainwater-harvesting structure were treatment factors. The results showed that the yield of sorghum was significantly higher under the tied contour and infiltration pits than standard contour at all distances from rainwater-harvesting practices and seasons. In all seasons sorghum varieties Macia and Sc Sila showed higher yield under the tied contour and infiltration pits than standard contour. However, regardless of the distance from rainwater-harvesting practice and season the sorghum variety, Macia showed a higher grain yield than Sc Sila. At each incremental level of N application to cattle manure, Macia had a higher grain yield than Sc Sila, and no significant grain yield benefits were shown in each variety at N application to cattle manure above 50 kg N ha−1.

摘要

矿物肥料的施用量不足，加上降水不可靠，导致津巴布韦小农区的高粱产量急剧下降。这需要创新的干预措施，以在不断变化的气候条件下提高产量。本研究评估了基于等高线的雨水收集方法和使用牛粪 + N 养分改良剂对高粱产量的影响。进行了裂区试验，其中雨水收集实践、高粱品种、牛粪+N 和与雨水收集结构的距离是处理因素。结果表明，在距离雨水收集方式和季节的所有距离下，捆绑等高线和渗透坑下的高粱产量均显着高于标准等高线。在所有季节，高粱品种 Macia 和 Sc Sila 的产量均高于标准等高线和渗透坑。然而，无论距离雨水收集实践和高粱品种季节的距离如何，Macia 的谷物产量都高于 Sc Sila。在牛粪施氮的每个增量水平上，Macia 的谷物产量都高于 Sc Sila，并且在牛粪施氮超过 50 kg N ha-1 时，每个品种的谷物产量没有显着提高。