Three patterns of potash application were used in the corn-wheat and rice-wheat rotation experiments,which were conducted in the upland and wetland of Siyang County, northern Jiangsu Province, and the wetland of Liyan...Three patterns of potash application were used in the corn-wheat and rice-wheat rotation experiments,which were conducted in the upland and wetland of Siyang County, northern Jiangsu Province, and the wetland of Liyang City, southern Jiangsu Province. The results of 5 cropping seasons (2 seasons/year)showed that the direct response of corn to K was larger than that of wheat, but no difference was found between rice and wheat in Siyang when the total annual amount of K was applied only in one cropping season. However, the response of wheat was much greater than that of rice in Liyang. If potash was applied in the preceding season, the residual effect of K on wheat was larger than that on rice both in Siyang and Liyang, but less than that on corn. The total effect (direct and residual effects) of K applied to corn or rice was greater than that to wheat in Siyang, but that to wheat was greater in Liyang. The direct and total effects of K application in the upland were larger than those in the wetland of Siyang; but for the wetland,the effects were larger in Liyang than in Siyang, especially in the wheat season. The results demonstrated that the most profitable practice to be recommended to the local farmers was to apply a limited amount of potash to only rice or corn but not to wheat. Equally applying half of the total annual amount of K to each of the crops may be advisable in order to lessen possible fertilization risks.展开更多
文摘Three patterns of potash application were used in the corn-wheat and rice-wheat rotation experiments,which were conducted in the upland and wetland of Siyang County, northern Jiangsu Province, and the wetland of Liyang City, southern Jiangsu Province. The results of 5 cropping seasons (2 seasons/year)showed that the direct response of corn to K was larger than that of wheat, but no difference was found between rice and wheat in Siyang when the total annual amount of K was applied only in one cropping season. However, the response of wheat was much greater than that of rice in Liyang. If potash was applied in the preceding season, the residual effect of K on wheat was larger than that on rice both in Siyang and Liyang, but less than that on corn. The total effect (direct and residual effects) of K applied to corn or rice was greater than that to wheat in Siyang, but that to wheat was greater in Liyang. The direct and total effects of K application in the upland were larger than those in the wetland of Siyang; but for the wetland,the effects were larger in Liyang than in Siyang, especially in the wheat season. The results demonstrated that the most profitable practice to be recommended to the local farmers was to apply a limited amount of potash to only rice or corn but not to wheat. Equally applying half of the total annual amount of K to each of the crops may be advisable in order to lessen possible fertilization risks.
