The nutrient and soil water status of a ferralsol in a broccoli field under different water management practices on a footslope position

Abstract

The study assessed the effectiveness of different water management practices on the nutrient status and soil water availability of a ferralsol under Broccoli growing a slope of Kabanyolo hill at Makerere university agricultural research institute Kabanyolo. Broccoli is one of the leading vegetables and a major source of Vitamins and other major nutrients to the body. The low broccoli production and yield in Uganda is mainly attributed to biotic and abiotic factors, among others water stress and nutrient deficiencies. Monitoring of an existing broccoli field experiment was conducted at Kabanyolo in Wakiso district to determine how effective the water management practices are with respect to extent of soil wetting, and distribution and soil water content with respect to field capacity. The crop was three months old and was grown under organic fertigation with NPK, poultry manure and mulched. Water used was salt free and organically fertigated supplied for at least one hour when moisture content is too low using a pump head of 4 cubic meters; but there was quantification of soil water content. Soils of the experimental site are mainly ferralsols and had an organic matter content of 4.53% -4.8%, deficient in most plant nutrients and average soil pH of 6.2. The soils based on textural analysis that showed sandy loams are prone to leaching if irrigation is poorly done. The experimental design was of a randomized complete block design with treatments: drip irrigation, rain spray and a rainfed field area as a control. Blocking was done along the slope and crop ridges were replicate for the eight weeks of study. high density drip irrigation Statistical analysis was done in GenStat 14th edition (VSN International Ltd) to show the differences in soil water content and other properties among treatments. Graphs of soil water content changes overtime was done in comparison to field capacity and permanent wilting point. The water content on the rain rainfed plot reduced to lower drainage limits. There was more wetting atleast more than eight times above the field capacity in the high density plot. There were more differences in the nutrient status between the rainfed and irrigated plots, Organic matter content is lower in the rainfed than irrigated plots.