GROWTH AND REGROWTH OF NEEM AFTER CUTTING IN SALINE - SODIC SOIL TREATED WITH ORGANIC INPUTS

ABSTRACT Soil salinity and sodicity are global problems since both promote the physical, chemical and biological degradation of soil, jeopardising the productive capacity of agricultural fields. Inorganic correctives or organic inputs are applied as an attempt to reduce the problem, alongside the use of salt -tolerant plants. This study aimed at evaluating the effects of organic inputs on the growth of neem (Azadirachta indica) strains in saline-sodic soil after cutting. Treatments were arranged in a randomised block design, with four replicates in a 3 × 5 factorial. Organic inputs - bovine manure, common bovine biofertilizer (equal parts of water and fresh bovine manure) and chemically enriched biofertilizer (common biofertilizer components combined with plaster, sugarcane molasses and cow’s milk) - were applied only once, after soil washing, two days prior to seeding, at the levels of 0, 3, 6, 9 and 12% of the substrate volume. Except effects on the stem diameter, the most efficient input was bovine manure, with strong effects on the height increase and biomass yield of neem plants after cutting, especially in treatments at a level greater than 6%. The organic inputs, despite increasing the soil salinity and sodicity in the interval between washing and cutting, stimulated biometric growth and biomass formation in saline-sodic soil.

摘要：土壤盐渍化与碱化是全球性环境问题，二者均可引发土壤的物理、化学与生物学退化，危及农田的生产能力。当前常通过施用无机改良剂或有机物料，搭配耐盐植物的应用来缓解该问题。本研究旨在探究有机物料对盐渍碱化土壤中刈割后印楝（Azadirachta indica）品系生长的影响。试验采用随机区组设计，设置3×5因子组合，共4次重复。供试有机物料包括牛粪、普通牛粪生物肥（水与新鲜牛粪按1:1体积配比）以及化学强化型生物肥（由普通生物肥组分与石膏、甘蔗糖蜜、牛乳复配而成），于土壤洗脱后、播种前2天一次性施用，施用量梯度为基质体积的0%、3%、6%、9%及12%。结果表明，除对茎粗无显著影响外，牛粪为最有效的有机物料，对刈割后印楝植株的株高增长与生物量产量均有显著提升效果，尤其在施用量高于6%的处理组中效果尤为显著。尽管有机物料在土壤洗脱至刈割的间隔期内会提升土壤盐渍化与碱化程度，但仍可促进盐渍碱化土壤中印楝的形态生长与生物量积累。