位于巴西圣保罗州东北部 Pontal 县的 Santa Helena 农场,大豆种植面积100公顷。在那里发现了大豆未熟开荚现象,造成颗粒不收。播种前的土壤分析表明,这种土壤的盐基饱和度为35%。说明必须施用石灰以中和土壤酸度。这种土壤钾的含量低,由于土地短期租给个人,农场主不愿投资采用施石灰中和酸度这一基本措施。这一地区由于施用石灰使大豆产量大约提高 Located on Santa Helena Farm in Pontal County, northeast of São Paulo, Brazil, the soybean plantation covers an area of ​​100 hectares. There, it was found that the phenomenon of immature soybean pod open, resulting in the particles do not accept. Soil analysis prior to sowing showed that the basal level of this soil was 35%. Note that lime must be applied to neutralize soil acidity. Because of the low potassium content in this soil, farmers are reluctant to invest in the basic measure of neutralizing acidity with lime as the land is rented to individuals for short periods. Soybean production in the area is about boosted by the application of lime