不同形态氮素对刺梨生长发育的影响

Effects of Nitrogen Form on the Growth and Development of Rosa roxburghii

刺梨砂培试验结果表明：增加营养液中硝态氮比例，能促进根系生长。用硝态氮与铵态氮配合作氮源，植株生长量大于单一用硝态氮、铵态氮或尿素。春季用尿素作氮源，植株生长弱。增大营养液中铵态氮比例，根、叶中游离氨基酸含量明显提高，叶中水溶性总糖含量增加，而淀粉含量下降，根中水溶性总糖和淀粉含量也随之降低。营养液中铵态氮比例占５０％和７０％时，叶中氮、磷、钙、铁、锌、铜元素含量明显提高，而硼、钼元素含量随铵态氮比例增大而降低。

The results of sand culture experiment showed that increasing NO-3-N ratio in nutrient solution could promote root growth of cili (Rosa roxburghii). The growth of the plants treated with nitrogen source of NO-3-N+NH+4-N was better than that of the plants treated with single nitrogen source (NO-3-N or NH+4-N or urea) . In spring, the plants treated with urea grew weakly. With increase of ratio of NH+4-N in nutrient solution, the free amino acid contents in roots and leaves and soluble sugar contents in leaves were obviously increased, and the starch contents in leaves and the soluble sugar and starch contents in roots were descreased. The contents of N, P, Ca, Fe, Zn and Cu in leaves were singnificantly increased when 50% or 70% of total nitrogen in nutrent solution was NH+4-N. The contents of B and Mo, however, descreased with increase of ratio of NH+4-N. 