Onion production costs as a function of water content and soil tillage

ABSTRACT Onion production is an agricultural activity whose yield is associated with environmental, market and cultural management factors. The objective of this study was to evaluate the cost of onion production as a function of the tillage system adopted and the soil water content at the moment of the operations. Three tillage systems were evaluated: P1 - one plowing + two harrowings + two seedbed raising operations; P2 - two harrowings + one seedbed raising operation; P3 - one harrowing + one seedbed raising operation; and four soil water contents: 12, 15, 23 and 26%, in experiment conducted at the Tourão irrigated perimeter, Juazeiro, BA, Brazil (9° 24’ 07.3” S; 40° 26’ 08.7” W, and altitude of 376 m), in 2017, in split plots, in a randomized block design, with four repetitions. The costs related to mechanized operations, manual operations, inputs and crop irrigation were determined. The economic efficiency was evaluated through the variables total cost and unit cost of onion production, gross revenue, net revenue and internal rate of return. The use of the tillage system with one harrowing, one seedbed raising operation and seeding, under the condition of 23% soil water content, resulted in higher economic efficiency.

摘要 洋葱生产是一类农业生产活动，其产量与环境、市场及栽培管理因素密切相关。本研究旨在评估洋葱生产成本与所采用的耕作制度以及作业时土壤含水量的关联关系。试验共设置3种耕作制度：P1为翻耕1次+耙地2次+作床2次；P2为耙地2次+作床1次；P3为耙地1次+作床1次；同时设置4个土壤含水量梯度：12%、15%、23%和26%。本试验于2017年在巴西巴伊亚州茹阿泽鲁市图朗灌溉区（南纬9°24’07.3”，西经40°26’08.7”，海拔376米）开展，采用随机区组裂区设计，设置4次重复。研究测定了机械化作业、人工作业、农用投入品以及作物灌溉相关的各项成本，并通过总生产成本、洋葱单位生产成本、总收入、净收入及内部收益率等指标评估经济效率。结果表明，当土壤含水量为23%时，采用仅需1次耙地、1次作床并播种的耕作制度，可获得更高的经济效率。