米老排不同种源苗期生长规律研究

摘要

Annual growth rhythms of Mytilaria laosensis seedlings from 6 provenances (Guangxi Rongxian, Shangsi, Debao, Jingxi, Longzhou, Pingxiang) were studied. The results were as follows: (1) The variance analysis of Mytilaria laosensis form different provenancesshowed that differences between tree heights were significant.(2) By using the Logistic equation analysis of different provenancesof Mytilaria laosensis seedling height, found that the coefifcient of determination of their Logistic iftting equation are all reached very signiifcant level and ranged from 0.963 to 0.991, respectively.The growth patterns ofthem were similar to”S”curves and the height growth rhythm of themwas iftted Logistic equation. (3) By equation the process of the seedling height could be divided into threestages, the early growth stage; rapid growth stage and late growth stage. Guangxi Shangsi provenance entered the rapid growthstageat first and shortest duration, Guangxi Jingxi provenance longest duration in the rapid growthstage, Guangxi Liuzhou provenance entered the rapid growthstage at the latest. Net growth of fast-growing amount of height the largest proportion of total growth is Guangxi Jingxi provenance, reaching 66.9%;second, Guangxi Liuzhou provenance;smallest, Guangxi Shangsi provenance, only 61.5%.(4) According to the clustering analysis of the seedling height of 6 provenances were divided into three groups, the ifrst groupincluded Guangxi Debao, Guangxi Pingxiang and Guangxi Rongxian provenance, which had the best height growth;the second groupincluded Guangxi Shangsi provenance, seedling height performance after the first group; The last groupincluded Guangxi LongzhouandGuangxi Jingxiprovenances.%对广西省容县（GXRX）、上思（GXSS）、靖西（GXJX）、龙州（GXLZ）、德保（GXDB）、凭祥（GXPX）6个米老排种源1年生苗木的苗高生长规律进行研究，探讨其高生长节律，旨在为米老排苗木的培育和种源的选择及利用提供参考。结果表明：（1）米老排不同种源苗高在生长方面存在极显著差异。（2）各种源米老排苗高Logistic方程的决定系数都达到极显著相关水平，分别为0.963～0.991，表明可以用Logistic方程来拟合米老排苗高生长节律，米老排的6个种源苗高年生长过程均表现出明显的“慢—快—慢”的“S”型生长节律。（3）利用Logistic方程可将不同种源米老排苗木生长过程划分为生长前期、速生期和生长后期3个时期，广西上思种源第一个进入速生期，但在速生期内持续的时间最短，广西靖西种源在速生期持续时间最长，进入速生期时间最晚的是广西龙州种源。广西靖西种源在速生期苗高净生长量占总生长量比重最大，达到66.9%；第二是广西龙州种源，为65.8%；最小的是广西上思种源，只有61.5%。（4）根据苗高的聚类分析结果，把6个米老排种源分成三大类，第一类是广西德保、凭祥、容县种源，苗高表现最好；第二类是广西上思种源，苗高表现仅次于第一类；第三类是广西龙州、靖西种源。