【作者】 王劲松；

【导师】 黄宝灵；

【作者基本信息】 广西大学 ， 生态学， 2011， 硕士

【摘要】 植物促生菌是指能通过各种直接或间接的作用有利于植物生长或促进植物生长的细菌,即PGPR(plant growth-promoting rhizobacteria),主要有固氮菌、解磷菌、解钾菌。前期从桉树、罗汉松、厚荚相思等林地分离、纯化到若干优良固氮菌、解磷菌、解钾菌。本研究将供试菌株进行了16S rDNA全序列分子分类学鉴定,并采用随机区组试验设计方法进行了桉树接种促生菌的苗期及后续造林试验,筛选出了一批促生效果较优的菌株,为桉树可持续林业的发展及大而积接种促生菌造林提供现实依据及指导意见。参与16S rDNA全序列分析的14个菌株在NCBI进行BLAST后,可以初步将其归于4个不同的属：不动杆菌属(Acinetobacter)有Nd、9K、4K、4Kv、14K 5个菌株；芽孢杆菌属(Bacillus)有N6、Nc、N1 3个菌株；葡萄球菌属(Staphylococcus)有K1、40K、0K、P、P1 5个菌株；厌氧球菌属(Anaerococcus)的菌株最少,仅有1株N5。综合苗期与造林试验结果,14个供试菌株接种广林9号无性系效果较优的为N1、N6、9K、NC、40K、14K这6个菌株。造林期各接种处理相对于对照组树高、地径增长率分别达13.95%-32.21%、32.49%-54.94%。对于筛选出的6个优良促生菌,进行了固氮菌与解钾菌之间促生效果差异的比较, t检验结果表明固氮菌接种促生效果要显著优于解钾菌。从在南宁市蔬菜研究基地接种8个不同固氮菌、解磷菌组合菌株于广林9号无性系的苗期及造林试验来看,接种促生效果相对较优的为N1+P、N1+L2+P、L2+P、4Y+L2+P这4个组合菌株。组合菌株N1+P、N1+L2+P、L2+P、4Y+P、4Y+L2+P的接种促生效果要显著优于单一菌株P。且采自桉树林地的组合菌株N1+P接种处理后苗高(树高)均要显著高于采自非桉树(罗汉松)林地的组合菌株处理4Y+L2。从在广西林科院接种8个不同固氮菌于广林9号无性系的苗期及造林试验中,研究表明接种促生效果较优的为D7+4Y、H6+L2、H6、D7、L2+4Y五个菌株(组合)。且三个组合菌株D7+H6、H6+L2、4Y+H6在造林期内接种促生效果均要显著优于单一菌株H6,而另三个组合菌株D7+L2、D7+4Y、D7+H6的接种效果未表现出显著优于单一菌株D7的现象。无性系广林9号及无性系3229接种同一固氮菌组合4Y+L2的对比试验中,接种组的苗高(树高)、地径(胸径)均要显著高于对照组。苗期试验,无性系广林9号及29接种后,地径分别比对照增长7.72%、20.18%,苗高增长量各达5.02%、16.40%；造林期时,接种固氮菌的的广林9号无性系及3229无性系的地径牛长量相对于对照组增长量各达8.04%-35.93%、4.9%-56.20%,树高增长量分别达35.74%、4.47%-72.22%。且苗期及第一次造林调查中，3229无性系接种效果要显著优于广林9号无性系,而第二次造林调查中,广林9号无性系的接种效果反而要显著优于3229无性系。在对桉树枝瘿姬小蜂危害的调查中,发现接种固氮菌的林木还农现出一定的环境抗逆性,在遭受桉树枝瘿姬小蜂严重危害后能较快恢复生长。更多还原

【Abstract】 Plant growth-promoting rhizobacteria is one kind of bacteria which can benefit the growth of plant through various direct or indirect effects,also called PGPR.They are mostly N-fixing bacteria、P-releasing bacteria and K-releasing bacteria.In the early time,we isolated and purified a number of good N-fixing bacteria、P-releasing bacteria and K-releasing bacteria from the woodland of Eucalyptus、Podocarpus macrophyllus and Acacia crassicarpa.The tested strains were classified and identified by 16S rDNA-Sequential Analysis,and inoculated on Eucalyptus for seedling and afforestation test with randomized block design.A number of strains which have good growth-promoting effect had been screened out.The test provided realistic foundation and guidance for the sustainable forestry development of Eucalyptus and large area of inoculated afforestation.14 Strains which involved in 16S rDNA-Sequential Analysis were blasted in NCBI,they can be divided into four different genus initially:the five strains Nd、 9K、4K、4Kv、14K belong to Acinetobacter;the three strains N6、Nc、N1 belong to Bacillus;the five strains K1、40K、30K、6P、P1 belong to Staphylococcus;only N5 belong to Anaerococcus.Considered the results of seedling and afforestation test, the better were six of fourteen tested strains inoculated Eucalypus grandis×E.urophylla GL9, they were N1、N6、9K、NC、40K、14K.The tree heights of various treatment groups were higher 13.95%-32.21% than the control group, the basal diameters were higher 32.49%-54.94% than the control group.Compared the effect of growth-promoting which be screened out six good PGPR between N-fixing bacteria(Nc,N6,N1) and K-releasing bacteria(40K,14K,9K), T test results showed that the effect of growth-promoting of N-fixing bacteria significantly superior to K-releasing bacteria.From the inoculation test results of 8 different mixed strains N-fixing bacteria and P-releasing bacteria from Vegetable research base,the four fixed strains N1+P、N1+L2+P、L2+P、4Y+L2+P showed a better inoculation effect of growth-promoting.The fixed strains N1+P、N1+L2+P、L2+P、4Y+P、4Y+L2+P showed a better inoculation effect of growth-promoting significantly than the single strain P.The fixed strains N1+P which from the Eucalyptus woodland showed a better seedling (tree)height significantly than the fixed strains 4Y+L2 which from the Podocarpus macrophyllus woodland.From the results of Eucalyptus grandis×E. urophylla GL9 inoculated with 8 different N-fixing bacteria in Guangxi Forestry Research Institute,the 5 strains D7+4Y、H6+L2、H6、D7、L2+4Y showed a better growth-promoting effect of inoculation.The three fixed strains D7+H6、H6+L2、4Y+H6 showed a better growth-promoting effect significantly than the single strain H6 in afforestation test.But the other fixed strains D7+L2、D7+4Y、D7+H6 did’t show a better growth-promoting effect significantly than the single strain D7.Contrast experiments of Eucalypus grandis×E.urophylla GL9 and E. urophylla×E. grandis 3229, which both inoculated by fixed strain 4Y+L2, the results showed that:the tree height and basal diameter of inoculation group were both higher than the control group.The basal diameters of GL9 and 29 were higher 7.72% and 20.18% respectively than the control group, the seedling heights of GL9 and 29 were higher 5.02% and 16.40% respectively than the control group in seedling test.The basal diameter of GL9 and 29 were higher 8.04%-35.93% and 4.9%-56.20% respectively than the control group, the tree height of GL9 and 29 were higher 35.74% and 4.47%-72.22% respectively than the control group in forestation test.The effect of inoculation of 29 significantly superior to GL9 in the seedling test and the first afforestation test, while the effect was on the contrary in the second afforestation test. In addition, the two Eucalyptus clones inoculated with N-fixing bacteria also showed high resistance in the environment, trees can resume the growth rapidly after suffering from the serious damage of Leptocybe invasa Fisher et La Salle.更多还原