Replication Data for: Impact of management practices on weed infestation, water productivity, rice yield and grain quality in irrigated systems in Côte d'Ivoire

Management practices that simultaneously enhance rice yield, water productivity, labor productivity, and grain quality are needed for improving crop production and mitigating the negative impact of water scarcity on food security. The objectives of this on-farm study were to evaluate the effects of water management practices including the safe alternate wetting and drying (AWD) method of irrigation on rice yield, water productivity, weed biomass, and grain quality, and identify the factors associated with their variabilities in the fields with AWD. On-farm trials were conducted over two years in 30 fields within two irrigation schemes in the region of Bouake, central Côte d’Ivoire. Before rice cultivation, in each field, three plots consisting of water management practices were established: continuous flooding (CF), safe AWD, and farmers’ practice (FP). Lowland weeds were dominant in rice fields in this study area. Large variations in weed biomass, rice yield, and water productivity were found across fields for each water management practice. Weed biomass and irrigation water input were lower under safe AWD than CF due to higher soil drying while there was no significant difference in rice yield between safe AWD and CF. Water productivity was higher under safe AWD than CF and FP. Rice milling recovery, head yield, and chalkiness were not significantly different among water management practices. Higher rice yield and water productivity in the safe AWD fields were associated with higher soil pH and nitrogen (N) fertilizer rate and better congruence between nitrogen fertilizer application and crop N demand. Milling recovery, head yield, and chalkiness in the safe AWD fields were strongly affected by the choice of rice variety. Combination of safe AWD with varieties having good grain quality characteristics and improved nutrient management practices could be recommended to the smallholder rice farmers to improve rice yield, water productivity, and grain quality and reduce labour requirement for irrigation and weeding particularly in schemes where lowland weeds are dominant.

为提升作物生产水平、缓解水资源短缺对粮食安全的负面影响，亟需能够同时提升水稻产量、水分生产率、劳动生产率与稻米品质的田间管理措施。本田间试验的研究目标为：评估包括安全交替灌溉（safe alternate wetting and drying, AWD）在内的水分管理措施对水稻产量、水分生产率、杂草生物量及稻米品质的影响，并明确采用AWD管理的稻田中各指标变异的相关影响因子。本研究于科特迪瓦中部布瓦凯地区的两个灌区的30块稻田中开展，试验周期为两年。水稻种植前，每块稻田设置3个接受不同水分管理措施的试验小区：持续淹灌（continuous flooding, CF）、安全AWD，以及农户常规灌溉措施（farmers’ practice, FP）。本研究区域的稻田以沼生杂草为优势杂草类群。各水分管理措施下，不同稻田间的杂草生物量、水稻产量与水分生产率均存在较大差异。与持续淹灌相比，安全AWD处理下的杂草生物量与灌溉用水量更低，这是因为土壤干燥程度更高；但安全AWD与持续淹灌的水稻产量并无显著差异。安全AWD处理的水分生产率高于持续淹灌与农户常规措施。不同水分管理措施下，稻米出米率、整精米率与垩白度均无显著差异。采用安全AWD管理的稻田中，更高的水稻产量与水分生产率与较高的土壤pH值、氮肥（N）施用量，以及氮肥施用与作物氮素需求的匹配度更高密切相关。安全AWD处理下的稻米出米率、整精米率与垩白度则受水稻品种选择的显著影响。针对沼生杂草为优势杂草的灌区，可向水稻小农户推广安全AWD与优质稻米品种结合、优化养分管理的综合措施，以提升水稻产量、水分生产率与稻米品质，同时降低灌溉与除草的劳动投入。