桑树新梢的枝叶养分分配比例状况研究

Nutrients Distribution Ratio Between Branches and Leaves of Mulberry Shoots

探讨桑树新梢在生长旺盛阶段枝条和叶片内养分分配比例的空间分布格局,为桑园土肥管理提供科学的依据。研究以雾化栽培的‘农桑14号’桑树品种为研究材料,研究枝叶间干物质和氮、磷、钾、钙、镁、铜、锌、铁、锰、硫、硼、钼和氯等13种营养元素的分配比例对空间位置的响应情况。枝叶间养分的分配比例为枝条每收获1 g干物质或营养元素时叶片可收获的干物质或营养元素的量,其表现为锰>铁>硼>钼>氮>钙>镁>锌>钾>硫>氯>磷>铜>干物质。除镁元素外,干物质和其余12种营养元素都表现出上部叶片在资源分配上具有显著的优势。而桑枝内各部位镁的枝叶分配比例相对稳定。因此,在桑枝生长的旺盛期,建议根据理论施肥量适当增加镁肥的供应,而对除镁以外其余12种营养元素所对应肥料进行适当的减肥调控。

For discussing the distribution ratio of dry material,N,P,K,Ca,Mg,Cu,Zn,Fe,Mn,S,B,Mo and Cl between the leaves and branches of new-born mulberry branches,a mulberry variety ‘Nongsang No.14’ is taken as the study material.Through studying the response of distribution ratio of dry material and the 13nutrient elements between leaves and branches to space location,the authors found that：the proportion of nutrient distribution between leaves and branches was the amount of dry material or nutrients of leaves when the branches produced 1 g of dry matter or nutrients,the performance was MnFeBMoNCaMgZnKSClPCudry material.Except Mg,dry matter and the other 12 nutrients showed that upper leaves had significant advantages in resource allocation.However,the distribution ratio of Mg in leaves and branches of mulberry was relatively stable.These results suggest that the supply of magnesium fertilizer should be appropriately increased according to the theoretical fertilization amount,and the other 12 nutrient elements should be reduced appropriately in the growth period of mulberry branches.