杨桐苗期施磷效应研究

采用盆栽试验，装风干土2.5 kg·盆^－1，研究了不同施磷水平对1年生杨桐Cleyera japonica苗木各项生长、生理指标及叶片含磷量的影响。结果表明：①施磷（P₂O₅）量在0 ～ 0.500 g·盆^－1范围内，杨桐各项生长、生理指标均随施磷量的增加而增加。当施磷量超过0.500 g·盆^－1后，各项生长、生理指标均表现下降趋势。②杨桐苗木叶片全磷含量，在适量的供磷范围内随施磷量的增加而增加，含磷量最高出现在0.500 g·盆^－1，超过此值后，随施磷量的增加而逐渐下降。③杨桐苗木各项生长指标与施磷量之间存在二次函数关系。综合本试验条件下各处理杨桐苗木施肥生长及生理效应可知，杨桐苗期最佳施磷量为0.441 ～ 0.603 g·盆^－1。图2表5参11

Phosphorus fertilization with Cleyera japonica seedlings

Based on a pot experiment,the effects of phosphorus fertilization on growth and physiological indexes and phosphorus content in leaves of one-year-old Cleyera japonica seedlings were studied.Seven P(P_2O_5)levels were set,0(ck),0.125,0.250,0.375,0.500,0.625 and 0.750 g·pot~(-1).Results showed that(1)with increasing levels of P from 0 to 0.500 g·pot~(-1),growth and physiological indexes in C.japonica seedlings increased,whereas with P increases over 0.500 g·pot~(-1),all indexes decreased.Also,(2)P in leaves increased with increasing levels of P from 0 to 0.500 g·pot~(-1) but decreased gradually with further P.Finally,(3)quadric relationships between growth indexes and P were noted.Based on growth and physiological indexes for one-year-old C.japonica seedlings,proper application of P was from 0.441 to 0.603 g·pot~(-1).