荧光假单胞菌对湿地松幼林生长量的影响

Effects of Pseudomonas fluorescens on the Biomass of Pinus elliottii Seedlings

将荧光假单胞菌Q2-87和1M1-96两菌株施用于1 a生、2 a生和3 a生的湿地松幼林;一个湿地松生长高峰期后,分析自然状态下幼林的生长规律,同时进行施菌前和施菌后苗高和地径的比较。结果表明:13片自然状态下生长的幼林生长情况符合前人总结的规律;2所有施菌的湿地松幼林经过一个生长高峰期后,高增长率均未得到显著提高;3施菌的1 a生幼林地径增长率提高极显著,施菌的2 a生幼林地径增长率提高显著,而施菌的3 a生幼林地径增长率提高不显著。通过分析,认为施菌的3 a生湿地松的地径增长率未提高不显著,原因是该龄期的湿地松对2,4-DAPG已经不敏感。因此,本文的结论是荧光假单胞菌Q2-87和1M1-96通过其产生的2,4-DAPG主要作用于低龄(2 a生以下)的湿地松,并导致其产生类似于生长素作用产生的促生效应,从而使湿地松地径明显地增长。

Pseudomonas fluorescens Q2-87 and 1M1-96 were applied to Pinus elliottii seedlings,which were one year old,two years old and three years old respectively,and after one growth peak stage the growth rhythm of the seedlings under the natural condition was analyzed and the height and basal diameter of the seedlings before and after the treatment of the bacterial agents were contrasted.The results showed as following：①The growth rhythm of the seedlings under the natural condition accorded with that the previous researchers summarized;②The height growth rates of all of the seed-lings inoculated with the two strains were not raised obviously;③The basal diameter growth rates of the seedlings,which were one year old,inoculated with the two strains were raised extremely obviously;the basal diameter growth rates of the seedlings,which were two years old,inoculated with two strains were raised obviously;the basal diameter growth rates of the seedling,which were three years old,inoculated with two strains were not raised obviously.Through the analysis,we think the reason that the basal diameter growth rates of the seedlings,which were three year old,were not raised obvi-ously was that the seedlings at this age were not sensitive to 2,4-DAPG.We concluded that the low age seedlings of slash pine,which were younger than two years old,turned thick by 2,4-DAPG,which is produced by Pseudomonas fluorescens Q2-87 and 1M1-96 and acts on the seedling similar to the effect of auxin.