磷素环境与马褂木种源的生长和干物质积累

自然土壤中有效磷含量很低,难以满足植物最佳生长的需要。据统计,在全世界13·19亿hm2的耕地中约有43%缺磷,而我国耕地则有2/3缺磷(何绪生等,1998)。我国南方地区高温多雨,富铝化作用明显,多数土壤呈酸性或强酸性,磷素固定强烈,土壤有效磷含量仅在1~2mg·kg-1(邱燕等,2003)。虽然施用磷肥的效果显著,但其利用率一般不超过10%,多为土壤固定并转变成植物较难吸收的Ca-P、Fe-P和Al-P等(熊毅,1997)。鉴于植物具有将土壤难溶态磷转化为有效态磷并加以吸收利用的能力,通过选育磷高效利用的植物品种来开发土壤中难溶态的磷素资源,可减小对施用磷…

Growth and Dry Matter Accumulation of Liriodendron chinese Provenances Related to Phosphorus Environment

Soil culture experiment at two phosphorus levels was conducted to study the relationship between phosphorus environment and growth as well as dry mater accumulation of six classical Chinese tulip tree provenances from various areas.The result showed that phosphorus supply would accelerate the growth and dry matter accumulation of Liriodendron chinese ,which would adapt to phosphorus starvation by increasing root-shoot-ratio and the relative value of root parameters.The western provenances were observed to grow better at two phosphorus levels than the eastern ones. The response model of phosphorus was varied with the provenances tested.It was found that Tongdao of Hunan and Wuyishan of Fujian were less sensitivity to phosphorus with high phosphorus efficiency and productivity,while Shaoyang of Hunan and Suichang of Zhejiang were more sensitivity to phosphorus with low phosphorus efficiency. Well-developed lateral root system and more fibrous roots under low phosphorus was perhaps one of the important reasons for the provenances with high phosphorus efficiency.It was preliminarily determined that Liping of Guizhou was an excellent provenance with moderate sensitivity to phosphorus, while Tongdao of Hunan was superior provenance with high tolerability to low phosphorus stress or high phosphorus efficiency.