Organic cultivation of onion under castor cake fertilization and irrigation depths

ABSTRACT. Two experiments were carried out to evaluate the effects that different doses of castor bean (0, 200, and 300 g m-2) and irrigation levels (204, 224, 278, and 321 mm in 2014, and 278, 302, 397, and 444 mm in 2015) have on both the productivity and quality of onion bulbs. In the experiments, the experimental design was randomized blocks (4 x 3 factorial scheme), with five replicates. Irrigation management was performed using a Simplified Irrigation Device (SID) in response to soil water tension in the treatment of highest irrigation depth. The following variables were evaluated: plant dry biomass (PDB), bulb dry biomass (BDB), total yield (TY), mean bulb fresh weight (MBFW), mean bulb dry weight (MBDW), mean bulb diameter (MBD) and water use efficiency (WUE). The highest irrigation depths positively influenced the mean production of onion bulbs, regardless of the applied dose of castor cake. The doses of castor cake positively influenced the production of onion bulbs when higher irrigation depths were applied.

摘要：本研究开展两组试验，旨在评估不同剂量蓖麻籽（0、200、300 g·m⁻²）与灌溉水平（2014年分别为204、224、278、321 mm，2015年分别为278、302、397、444 mm）对洋葱鳞茎产量与品质的影响。试验采用随机区组设计（4×3因子设计方案），设置5次重复。在最大灌溉深度处理组中，采用简易灌溉装置（Simplified Irrigation Device，SID）依据土壤水张力实施灌溉管理。本试验测定的指标包括：植株干生物量（Plant Dry Biomass，PDB）、鳞茎干生物量（Bulb Dry Biomass，BDB）、总产量（Total Yield，TY）、平均鳞茎鲜重（Mean Bulb Fresh Weight，MBFW）、平均鳞茎干重（Mean Bulb Dry Weight，MBDW）、平均鳞茎直径（Mean Bulb Diameter，MBD）以及水分利用效率（Water Use Efficiency，WUE）。结果表明，无论施用何种剂量的蓖麻饼，最大灌溉深度均对洋葱鳞茎平均产量产生正向促进作用；当灌溉水平较高时，蓖麻饼施用剂量可正向提升洋葱鳞茎产量。