施肥对烤烟生长及根际土壤磷钾养分的影响?

为研究不同施肥处理对烟苗生长和根际磷钾养分的影响，采用根箱培养技术，设置有机肥、化肥、有机无机配施、不施肥（对照）4种施肥处理。结果表明，在有机无机配施的处理中，烟苗的生物量、磷钾吸收量均高于其他处理，比对照分别提高了1.2倍、1.5倍和1.7倍。在烟苗根系附近，土壤有效磷钾的含量低于远根区，说明烟苗的吸收速率大于土壤供应速率，合理施肥成为调节烤烟根区磷钾营养的重要手段。根际Ca-P和O-P含量比较稳定，为土壤潜在磷源。有机无机配施提高了烟苗根际有效磷的含量，近根区的Al-P、Fe-P显著降低，酸性磷酸酶活性显著提高，说明有机无机配施增强了烟苗利用Al-P、Fe-P和有机磷的能力。在生产实践中，提倡化肥与有机肥的合理配合施用，对于保持土壤养分的持续供应、提高磷钾利用效率、促进烟苗的生长发育和生产优质烤烟有重要的意义。

Effects of Fertilization on the Growth of Flue-cured Tobacco P and K Nutrition in the Rhizosphere

Flue-cured tobacco seedlings were cultured in root boxes to investigate the effect of fertilization on phosphorus and potassium in the rhizospheric nutrition of flue-cured tobacco. The tobacco seedlings were supplied with chemical fertilizer, organic fertilizer and the mixture of chemical and organic fertilizers respectively. The blank treatment was established in the same way except without fertilizer supplied. The result showed organic fertilizer and the mixture of chemical seedling biomass, smoke, phosphorus, potassium uptake were higher than the contrast, were increased 1.2 times, 1.5 times and 1.7 times. Available P and K in the soil near the roots of tobacco seedlings were much higher than those far from the roots, indicating faster absorption of P and K by the seedlings than the movement toward to soils. The reasonable application became adjust flue-cured tobacco root zone phosphorus and potassium nutrition the important means. Ca-P and O-P content were stable and the potential soil phosphorus source. Organic fertilizer and the mixture of chemical raised greatly the available P in the rhizsophere of tobacco seedlings. Al-P and Fe-P in the soil near the roots were much higher than those far from the roots. It also increased obviously the activity of acid phosphatase in the rhizospheric soil, indicating organic fertilizer and the mixture of chemical increased the ability of the Al-P,Fe-P and organ phosphorus. In the production practice, advocates of coordinated chemical fertilizer and organic fertilizer to keep a steady supply of soil nutrient and improve the nutrient utilization efficiencies of P and K, promotion of the growth and development of smoke seedlings and production quality flue-cured tobacco have important significance.