| Eucalyptus grandis is the main kind of Eucalyptus spp. for pulpwood forest and returning the grain plots to forestry. Nowadays research on Eucalyptus grandis in the fields of man-made forest demand for land capability, interaction between Eucalyptus grandis and associated species, genetic variation, stability of ecosystem, correlativity of ecological demands and economic development, etc. have been the key items.Eucalyptus grandis is the typical mycorrhiza nutritional type tree, and it plays an important role in man-made forest's land capability maintenance and stability of ecological system. To develop and utilize mycorrhiza resource, improve growth and stress resistance of Eucalyptus grandis, our study focused on diversity and ecosystem characterization of macromycetes in the Eucalyptus grandis inforest, inquiring into relations between mycorrhiza and Eucalyptus grandis, grasping ectotrophic mycorrhiza regularities of distribution of Eucalyptus grandis and providing theory evidence of stabilizing man-made forest ecological system and sustainable development.On the base of the study, we can provide evidence in the application of mycorrhiza and utilization of fungi resource. The results were as the follows:(1) The article surveyed the mycorrhizal fungi of Eucalyptus grandis in Sichuan. The results showed that there are 17 species belong to 10 genus under the Eucalyptus grandis inforest, among which seven species were ectotrophic mycorrhiza, eleven edible fungi, ten medicindl fungi and four others. Vascellum pretense and Scleroderma areolatum were the predominant fungus, and Trichlloma argyreum was the new record species in Sichuan provience.(2) The macrofungi resources were surveyed termly from the Eucalyptus grandis inforest to know the diversity of the macrofungi and its ecological distribution. The results showed that there are 17 species belong to 10 genus under the Eucalyptus grandis inforest, Vascellum pretense and Scleroderma areolatum were the predominant fungus, and five species of Scleroderma, Pisolithus tinctorius and Tricholoma argyreum were ectomycorrhizal fungi. The living conditions of macrofungi were as follows:they grown in the areas of schattenseite and semi-nouthward, the altitude was between 400 and 650m, crown density exceeded 0.7, pH was between 4.2 to 5.8, and the content of the organic matter, N, P and K was higher than the contrast. The diversity analysis revealed that the macrofungus in Shawan and Jinyan of Leshan, Pengshan and Danling of Meishan were copious, and they had a good degree of homogeneity, dominance and diversity. The macrofungus from the Eucalyptus grandis inforest contribute to the quality of forestry and stability of the man-made forest ecosystem. Simpson index showed that it was highest in Pengshan (>0.6), then Danling, Jinyan and Shawan. The diversity index also showed that it was highest in Meishan (about 2.0), and the index was above 1.2 in Jinyan, Danling and Leshan.(3) The mycelium was cultivated from the fruiting body of puffballs which collected from the Eucalyptus grandis inforest, and the genomic DNA was extracted as template. Six puffballs pure culture were obtained, and the ITS sequences were also submitted to Genbank. The accession numbers were as belows, Calvatia gigantea (HM237179), Lycoperdon wrightii, Vascellum pretense (HM237178),S. citrinum (HM237176),S. aurantium (HM237174),S. bovista (HM237175),S. polyrhizum (HM237173), Scleroderma sp.11-1 (HM237170), Scleroderma sp.2-2 (HM23717) and Scleroderma sp.5-2 (HM237172), respectively.Subsequently, the internal transcribed spacer (ITS) region in rDNA gene was amplified, cloned and sequenced. The phylogenetic tree of puffballs was first built based on different part of ITS region. The results showed that six species of puffballs was cultivated successfully using PDA medium after comparing the sequences of puffballs fruiting body and mycelium ITS regions. The rDNA-ITS region of different puffballs was 607 bp to 766 bp in length. Analysis of phylogenesis revealed that the genetic relationship between the Scleroderma and Pisolithus, Calvatia, Lycoperdon and Vascellum was close. The three undetermined species, Scleroderma sp.11-1, Scleroderma sp.2-2 and Scleroderma sp.5-2, could probably be S. aurantium. The sequence of ITS1-5.8S rDNA-ITS2 can used as an evolutionary marker between different genus, and ITS2 as an evolutionary marker in genus. Thus, this work laid the foundation of studying the ectotrophic mycorrhiza, the mechanisms of action, the classification of puffballs and its exploitation and utilization.(4) The ectotrophic mycorrhiza fungi were inoculated into culture clone of Eucalyptus grandis using multiple factor orthogonal test. The results showed that infection of treatment using ectotrophic mycorrhiza fungi was above 50%. The value of seedling height, caliper, fresh weight and the overground/underground ratio were higher than compound fertilizer or sterile treatments.The chlorophyll content measurement showed that the content of Chlorophyll a, Chlorophyll b and total Chlorophyll varied in different treatments. The variation trend was as follows:ctotrophic mycorrhiza treatment> compound fertilizer treatment> sterile treatment treatment. However, it was not same in photosynthesis index. It was found that negative correlation between photosynthetic rate and CO2 concentration, positive correlation between photosynthetic rate and transpiration. Besides, the positive correlation between stomatal conductance and transpiration rate, CO2 concentration was observed.The N, P, Ca and Mg contents were higher than sterile treatments in nursery stock, but it was not significant in K content. The soluble sugar in nursery stock can be increased after inoculation, moreover, free amino acid content can also stabilized in high degree, but there was not significant correlations between reducing sugar and total protein content.(5) Soil urease activities of E. grandis rhizosphere was high, there are activities of phosphate enzyme in the each treatments of acidic, medium and alkali, the acid phosphate enzyme activity was higher than activities of acidic, medium phosphate enzyme, and the enzyme activities had correlation with time, the results generally showed that soil phosphate enzyme activity in July were higher than that in May and September. The number of soil microbes had close relation to enzyme after vaccinating Ectomycorrhiza, and the number of soil microbes and secretion of enzyme increased in may, but soil microbes decreased though secretion of enzyme increased after July and September, secretion of enzyme reached its highest level after July, but had the decreased trend.Eight funguses,19 bacterial (eight nitrogen-fixing bacteria) and six actinomycete were found in the soil after vaccinating Ectomycorrhiza of E. grandis seedling. A negative correlation was found between fungus, bacterial and pH, and fungus, bacterial, actinomycete had positive correlation with organic matter after 60 days. Significant correlation was found between Available N and the number of nitrogen-fixing bacteria, organic matter had significant correlation between fungus, bacteria, actinomycete and the number of nitrogen-fixing bacteria respectively after 120 days. A negative correlation was found between pH and the number of fungus, but the relationship of correlation between organic matter, TN indicators and number of microbes changed after 180 days.
|
PDF Full Text Request