Organic cabbage growth using green manure in pre-cultivation and organic top dressing fertilization

ABSTRACT The experiment was conducted in (Integrated Agroecological Production System in Seropedica-RJ) Sistema Integrado de Produção Agroecológica (SIPA), Seropédica-RJ, to evaluate the effect of two maize populations in relation to baby corn productivity and shoot mass, to determine the contribution of pre-cultivated maize, green velvet and organic topdressing fertilization in the agronomic performance of cabbage (Brassica oleracea var. capitata). The experimental design consisted of randomized blocks with three treatments (maize population of 100,000 and 200,000 plants ha-1 and green velvet at 100,000 plants ha-1) and eight replicates. After that, cabbage was transplanted in the straw of these species, adopting a randomized block design allocated in split plots, totalizing six treatments, being three pre-cultivation practices and two organic topdressing fertilization doses (with or without 50 g fermented organic compost per planting hole). Considering “baby corn” productivity, no differences were observed compared to maize populations, with an average productivity of 822.5 kg ha-1. Green velvet pre-cultivation obtained the highest shoot dry mass (8.4 t ha-1). Cabbage crop was improved by green velvet pre-cultivation, reaching 60.7 t ha-1 and organic topdressing fertilization, reaching 60.4 t ha-1; however, in the presence of green velvet straw, topdressing fertilization did not promote additional yield benefit of this crop. Thus, we noticed that green manure using green velvet increased cabbage productivity, submitted to organic management, when compared to maize pre-cultivation, making it able to replace organic topdressing fertilization.

摘要 本实验于巴西里约热内卢州塞罗佩迪卡市的综合农业生态生产系统（Sistema Integrado de Produção Agroecológica, SIPA）开展，旨在评估两种玉米种植密度对迷你玉米（baby corn）产量及地上部生物量的影响，并探明前茬种植玉米、绒叶豆（green velvet）与有机追肥对结球甘蓝（Brassica oleracea var. capitata）农艺性状的调控效应。实验采用随机区组设计，设置3种处理（玉米种植密度分别为100000株·公顷⁻¹、200000株·公顷⁻¹，以及绒叶豆种植密度100000株·公顷⁻¹），共8次重复。后续将甘蓝移栽至上述作物秸秆覆盖的田块，采用裂区随机区组设计，总计设置6种处理：3种前茬种植模式，以及2种有机追肥施用量（种植穴施加或不施加50g发酵有机堆肥）。针对迷你玉米产量，不同玉米种植密度间未观测到显著差异，平均产量为822.5 kg·公顷⁻¹。绒叶豆前茬处理的地上部干物质积累量最高，达8.4 t·公顷⁻¹。绒叶豆前茬与有机追肥分别可使甘蓝产量提升至60.7 t·公顷⁻¹与60.4 t·公顷⁻¹；但当田块存在绒叶豆秸秆覆盖时，追肥并未为甘蓝带来额外的增产效益。综上，相较于玉米前茬，采用绒叶豆作为绿肥可提升有机管理模式下结球甘蓝的产量，且能够替代有机追肥施用。