江苏省不同类型土壤基础供氮能力对水稻产量的影响

以近年来江苏省广泛种植的19个不同基因型水稻品种为材料，在11个县市区196个田块进行试验，研究江苏省不同类型土壤基础供氮能力对水稻产量的影响。结果表明，土壤基础产量与其所能达到的最佳实际产量呈显著正相关。不同类型土壤基础产量由大到小依次为黏土、壤土、砂土。不同土壤基础产量及其土壤基础供氮量（全生育期植株总吸氮量）变异范围都很大，但不同土壤基础产量和土壤基础供氮萤呈极显著正相关。获得相同基础产量时不同类型土壤基础供氮量由大到小依次为黏土、壤土、砂土。100kg基础产量需氮量呈粳稻大于籼稻的趋势。不同基因型水稻100kg基础产量需氮量由大到小均依次为黏土、壤土、砂土。江苏省196个田块士壤碱解氮含量与基础供氮量呈现出线性正相关的趋势（R^2〈0．4000），但相关性较差。

Effects of basic nitrogen supply capacity of different texture soils on rice yield in Jiangsu Province

The effects of basic nitrogen supply capacity(BNC)of different texture soils(sandy soil,loam soil and clay soil)on potential rice yield(PRY)in Jiangsu Province were studied at 196 experiment plots in 11 counties with 19 different rice varieties.Results showed that basic rice yield(BRY),meaning rice yield without nitrogen application during whole growth stage,was significantly correlated to PRY.BRY of clay soil was the highest in three kinds of soil,and the BRY of sandy soil was lowest.BRY was positively correlated to BNC significantly,even the BRY and BNC varied largely with soil type.While the same BRY,BNC of clay soil was higher than that of loam soil and sandy soil.Nitrogen requirement for 100 kg grain yield of BRY of japonica rice was higher than that of indica rice.BNC was positively correlated with alkaline hydrolysable for all treatments,but the coefficient of determination(R~2)is lower than 0.400 0.