不同栽植密度对斑叶稠李苗木培育质量的影响

Effects of Different Planting Densities on Cultivating Quality of Padus maackii Seedlings

以斑叶稠李(Padus maackii)1年生苗木为研究对象,通过4种不同栽植密度(60、80、100、120株·m^-2)试验,测定其苗木形态、生物量、光合速率及养分含量,旨在探明不同密度对斑叶稠李苗木生长及养分含量的影响,为其高质量苗木培育提供理论依据。结果表明:(1)栽植密度显著影响苗木生物量,各密度下苗木根、茎、叶生物量由大到小顺序均为80株·m^-2>60株·m^-2>100株·m^-2>120株·m^-2;60和80株·m^-2密度下斑叶稠李苗木质量指数显著高于100和120株·m^-2密度处理。(2)栽植密度显著影响苗木侧根数,在80株·m^-2的密度下达到最大;(3)80株·m^-2密度较其它密度显著提高了苗木氮、磷、钾养分含量。(4)叶生物量、根生物量和侧根数与苗木各质量指标间Pearson相关性系数均达到了显著水平(P<0.1),而光合速率和主根长与苗木各质量指标均不相关(P>0.1)。综合以上结果,斑叶稠李1年生苗木最适栽植密度为80株·m^-2,且密度处理主要影响斑叶稠李苗木叶生物量、侧根数及根生物量指标,进而影响苗木质量。

We studied the growth and nutrient content of the one-year-old Padus maackii seedlings,which provided a theoretical basis for the field cultivation.The morphology,biomass,photosynthetic rate and nutrient content of the seedlings were determined under four planting densities,including 60,80,100 and 120 ind.·m^-2.(1)The biomass was affected significantly in different planting densities.The order of leaf,stem and root biomass of P.maackii seedlings in different planting densities were 80>60>100>120 ind.·m^-2,respectively.The quality index of P.maackii seedlings at the density of 60 and 80 ind·m^-2 were significantly higher than that at the density of 100 and 120 ind.·m^-2.(2)The number of lateral roots were affected significantly under different density treatments,which was maximum at the density of 80 ind.·m^-2.(3)The nutrient content of N,P,K were highest under 80 ind.·m^-2 density treatment,and were significantly higher than that in other treatments.(4)The seedling quality indexes were significantly positively correlated with the leaf biomass,root biomass and lateral root number(P<0.1),but were not correlated with the taproot length and photosynthetic rate(P>0.1).Thus the optimal seedling density of one-yearold P.maackii was 80 ind.·m^-2,and the leaf biomass,lateral root number and root biomass of P.maackii were affected significantly by planting densities,then affected the seedling quality.