磷肥和石灰对酸性土壤上一年生黑麦草生长的影响

在二种强酸性、严重缺磷的土壤上，对一年生黑麦草做了磷肥和石灰用量的盆栽试验．结果表明：严重缺磷的土壤，施磷可成倍增加黑麦草产量；黄筋泥需磷量相对红砂土较高些．施磷量与收获后土壤速效磷含量与黑麦草产量密切相关，但土壤速效磷的等级指标，红砂土应比黄筋泥高些．石灰的增产作用远比磷肥低，增产效果还因施磷量不同而不同．在施石灰提高土壤ｐＨ达５．５的范围内，施磷量低的处理产量随石灰施用量的增加而增加；施磷量较高时，石灰的增产效果停留在低石灰用量上．

Effect of phosphorus fertilizer and lime application on growth of annual ryegrass grown in acid soils. Journal of Zhejiang Agricultural University

Pot experiments were conducted to investigate the effects of phosphorus fertilizer and lime application on ryegrass growth on highly acid and P deficiency soils. The results show that application of phosphorus fertilizers could considerably increase dry matter yields of annual ryegrass grown on P deficiency soils.The requirement of phosphate fertilizer is relatively higher for Quaternary red soil than that for Sand red soil.Close correlation was found between phosphate application rates and soil available P as well as dry matter yield of ryegrass.Whereas critical soil available P is higher for sand red soil than for Quaternary red soil.Effect of liming on ryegrass yield was less obvious than that of phosphate fertilizer.The increase in yield due to lime application differed with phosphate fertilizer application rates .The yields increased with increasing lime application rates at low P application rates. When soil pH is lower than 5.5, at higher phosphate application rates less effect of high rate of lime application on yield were observed.The results demonstrate that P is a more important factor than liming for ryegrass growth on acid red soils.