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美国东南部的甘薯生产正朝着连作的方向发展。不采用轮作的原因,主要是由于土地价格上涨以及适宜种甘薯的土地减少。甘薯连作已产生了两个问题:一是产量下降,二是薯块开裂加重。Peterson 和 Lana 发现,在同一块地上连续种植甘薯,即使施肥适当也减产70%。他们还发现,栽培在同一小块土地上的甘薯减
Sweet potato production in the southeastern United States is moving in the direction of continuous cropping. The reasons for not using the rotation are mainly due to the increase of land prices and the reduction of land suitable for planting sweet potatoes. Continuous cropping has produced two problems: First, the decline in production, the second is the increase in potato cracking. Peterson and Lana found that continuously growing sweet potatoes on the same plot reduced yields by 70%, even when properly fertilized. They also found that sweet potatoes grown on the same patch of land were reduced