基于豆梨容器苗生长和养分库的最佳施肥量确定

通过研究施用不同缓释肥量对豆梨(Pyrus calleryana Decne)容器苗生长和养分库构建的影响,揭示其对豆梨容器苗生长及其养分分配的规律,为豆梨容器苗培育的施肥技术提供依据。采用单因素随机区组设计,每m3基质中缓释肥施肥量设置4个水平,即F1(1.5 kg·m-3)、F2(2.0 kg·m-3)、F3(2.5 kg·m-3)、F4(3.0 kg·m-3),容器为无纺布袋(规格10 cm×14 cm)。结果表明:施肥量为2.0 kg·m-3时,豆梨容器苗苗高、地径生长量均达最大值,分别为48.23 cm、5.22 mm,同时具有最大的整株干质量,为6.56 g。施用缓释肥有利于提高豆梨容器苗养分库中氮积累量,2.0 kg·m-3(F2)施肥量时实现了氮养分库的最大积累量,整株氮积累量为136.86 mg·株-1。而缓释肥施肥量的增加对养分库磷积累量的提升不显著,施肥量1.5 kg·m-3(F1)已能满足磷素需求,此时根系表现出积极的磷吸收率,其积累量达2.75 mg·株-1。总之,从苗木生长和养分状况两方面考虑,F2(2.0 kg·m-3)施肥量时苗木生长表现最优,且满足豆梨1年生苗氮养分库的需求,而F1(1.5 kg·m-3)施肥量就能基本实现容器苗磷素养分加载。

Determination of Optimum Amount of Slow-release Fertilizerw ith Grow th and Nutr ients Reserves of Pyrus calle-ryana Decne Container Seedlings

We studied the features of its growth and construction of nutrient reserves under different levels of Slow-release fertiliz-er(SRF)to show the rules of the growth and nutrient distribution of container seedlings for the fertilization techniques of Pyrus calleryana Decne.The experiment was designed as a univariate completely randomized blocks, and the amount of SRF was set with four levels:F1:1.5 kg· m-1,F2:2 kg· m-3,F3:2.5 kg· m-3,and F4:3 kg· m-3.The containers were non-woven bags(10 cm×14 cm).When the level of SRF was 2.0 kg· m-3level,the container seedlings grew best. The maximum value of the height, diameter and the dry weight of whole plant were, respectively,48.23 cm,5.22 mm, 6.56 g.The application of SRF increased N content of nutrients reserves,and the largest nutrients reserves was constructed at 2.0 kg· m-3,when N content of nutrients reserves of whole seedlings was 136.86 mg per plant.While P content of seed-lings was not changed by increasing SRF loading.F1(1.5 kg· m-3)would be enough to provide P for constructions of nu-trients reserves.At this time,the root system showed a positive uptake rate to P, and its content was 2.75 mg per plant. Therefore,F2(2.0 kg· m-3)level of SRF met N nutrients reserves needs of container seedlings,while F1(1.5 kg· m-3) level could basically achieve the construction of P nutrient reserves.