【作者】 徐辉；

【导师】 唐明；

【作者基本信息】 西北农林科技大学 ， 微生物学， 2009， 硕士

【摘要】 本研究通过调查府谷清水川流域砒砂岩区主要造林树种沙棘（Hippophae rhamnoides）和刺槐（Robinia pseucdoacacia）根际丛枝菌根真菌（Arbuscular Mycorrhizal fungi,AMF）资源及AMF侵染情况,分析土壤因子对AMF在清水川流域砒砂岩区分布的影响;采用盆栽法接种AMF于刺槐苗木,研究在砒砂岩土壤中接种AMF刺槐苗期生长和生理生化指标的变化,探讨接种AMF和根瘤菌对刺槐根际砒砂岩土壤酶活性、土壤营养状况、球囊霉素含量的影响。得出以下结论:1. AMF资源及侵染情况。从府谷清水川流域砒砂岩区沙棘和刺槐根际土中共分离鉴定出Acaulospora.bireticulata、A.excavata、A.rehmii、Glomus.aggregatum、G.constrictum、G.fasciulatum、G.geosporum、G.intraradices、G.microaggregatum、G.mosseae、G.pustulatum、G.reticulatum和Scutellospora.heterogama13种AMF,其中摩西球囊霉和地球囊霉为该区域的优势种。AMF平均孢子密度为5.6个·g^-1干土,侵染率为90.6%,球囊霉素含量397.1mg·kg^-1。2.土壤因子对刺槐AMF的影响。刺槐和沙棘菌根侵染率与土壤有效磷、有效氮、有机质和pH呈正相关,其中pH达到显著水平（p<0.05）。刺槐球囊霉素含量与土壤有效磷和有效氮含量呈显著正相关（p<0.05）,与pH和有机质含量呈负相关。4种土壤因子对刺槐菌根侵染率直接作用为pH>有效氮>有机质>有效磷,pH和有效氮起主要作用;对球囊霉素的直接作用的为有效氮>有机质>有效磷>pH,有效氮和有机质起主要作用。3.土壤因子对沙棘AMF的影响。沙棘菌根侵染率与有效磷、有效氮、有机质和pH呈正相关,其中pH达到显著水平（p<0.05）。AMF种类与有机质和pH呈正相关,与有效磷和有效氮呈负相关,其中有效氮差异极显著（p<0.01）,有效磷和有机质差异显著（p<0.05）;球囊霉素含量与有效磷极显著正相关（p<0.01）、与有效氮和有机质含量呈正相关,与pH呈负相关。对菌根侵染率的直接作用为pH>有效磷>有机质>有效氮,pH和有效磷起主要作用;对AMF种类的直接作用为有机质>pH>有效磷>有效氮,有机质和pH起主要作用;对球囊霉素的直接作用为有效氮>有效磷>有机质>pH,但以有效磷和pH的间接作用为主。4.接种AMF对刺槐生长的影响。接种G.mosseae和G.constrictum的刺槐干重分别比对照提高74.9%和64.3%,地径提高36.8%和26.3%,株高提高41.5%和33.1%,根系活力提高61.8%和42.8%,丙二醛含量分别降低27.1%和30.6%,游离脯氨酸含量降低46.1%和35.7%,SOD酶活性提高62.5%和50%, CAT酶活性提高218.6%和131.7%,POD酶活性提高152.8%和90.4%,均达到显著差异（p<0.05）。两种AMF相比,地径和株高差异不显著,对干重和根系活力的促进作用G.mosseae大于G.constrictum,差异极显著（p<0.01）,说明在砒砂岩土壤中AMF的侵染增强了刺槐根系活力,提高抗氧化酶系活性,降低质膜氧化程度,有利于刺槐的生长。5.AMF和根瘤菌对刺槐根际土壤酶活性的影响。与对照相比,接种AMF根际土壤脲酶活性提高1.5倍、碱性磷酸酶活性提高2.7倍、蔗糖酶活性提高2.0倍,接种根瘤菌脲酶活性提高1.9倍、碱性磷酸酶活性提高2.2倍、蔗糖酶活性提高1.4倍,接种AMF和根瘤菌脲酶活性提高3.4倍、碱性磷酸酶活性提高4.0倍、蔗糖酶活性提高2.9倍,各种接种处理的土壤酶活性显著高于未接种的处理（p<0.05）;接种处理的土壤脲酶活性为双接种>根瘤菌>AMF,碱性磷酸酶和蔗糖酶活性为双接种>AMF>根瘤菌,双接种处理显著高于单接种（p<0.05）,更能提高砒砂岩土壤酶的活力。6.AMF和根瘤菌对刺槐根际土壤养分的影响。与对照相比,接种AMF土壤速效磷含量降低2.8%、速效氮提高6.4%、有机质提高4.8%,接种根瘤菌土壤速效磷降低3.1%、速效氮提高19.6%、有机质提高3.4%。双接种处理土壤速效磷降低6.0%、速效氮提高24.2%、有机质提高5.4%。各接种处理土壤pH有所降低,但差异不大。同时接种AMF和根瘤菌土壤速效氮、有机质含量较单接种显著提显著提高（p<0.05）,根瘤菌的固氮作用和AMF利于宿主磷素的吸收形成互补优势。7.AMF、根瘤菌对刺槐根际球囊霉素含量的影响。接种AMF和双接种比未接种对照的球囊霉素分别提高112.2%和243.4%,差异显著（p<0.05）。AMF和双接种盆钵刺槐远高于野外刺槐,说明接种AMF和双接种能提高球囊霉素含量。球囊霉素含量与土壤酶活性、有效N、有机质和植株生长成正相关,与有效磷和pH呈负相关性;球囊霉素含量越高,越有利于土壤形成微团聚体,施加适量氮肥磷肥、接种AMF的同时接种根瘤菌将有效提高球囊霉素含量,改良砒砂岩土壤。更多还原

【Abstract】 In this study, by investigating the main tree species Hippophae rhamnoides and Robinia pseucdoacacia rhizosphere AMF (Arbuscular Mycorrhiza Fungi) resources and infection in soft rock zone of Qingshuichuan valley of FuGu, analysised soil factors impact on distribution of AMF; Pot culture experiments were carried out to study the inoculation effects with the arbuscular mycorrhizal fungi on the growth and some physio-biochemical indexes of Hippophae rhamnoides seedlings under soft rock soil. Discussion impacts of AMF and Rhizobium inoculation on the Soft Rock R.pseucdoacacia rhizosphere soil enzyme activities, soil nutritional status, glomalin content. The results were as follows:1. AMF of resources and infection. 3 family 13 genera AMF were isolated and identified from the rhizosphere of R.pseucdoacacia and H.rhamnoides in soft rock zone of Qingshuichuan valley of FuGu: Acaulospora.bireticulata、A.excavata、A.rehmii、Glomus.aggregatum、G.constrictum、G.fasciulatum、G.geosporum、G.intraradices、G.microaggregatum、G.mosseae、G.pustulatum、G.reticulatum、Scutellospora.heterogama. G.constrictum and G.mosseae were the dominant ones in this region. the average total colonization rate of AM fungi was 90.6%, and the average spore density was 5.6g-1soil, the average glomalin content is 397.1 mg·kg-1.2. Soil factors on the impact of R.pseucdoacacia AMF. The AMF colonization of H. rhamnoides and R.pseucdoacacia had positive correlation with available P, available N, organic matter and pH, in which the level of pH was significant (p <0.05). R.pseucdoacacia glomalin content with soil available P and available N content was significant positive correlation (p <0.05), with pH and organic matter content was negatively correlated. Four kinds of soil factors on the mycorrhizal infection rate of R.pseucdoacacia for the direct effect: pH> available N > organic matter> available P, pH and available N played a major role. The direct effect on glomalin content: available N> organic matter> available P> pH, available N and organic matter played a major role. 3. Soil factors on the impact of H.rhamnoides AMF. The AMF colonization of H. rhamnoides had positive correlation with available P, available N, organic matter and pH, in which the level of pH was significant (p <0.05). AMF species with organic matter and pH were positively correlated, with available P and available N were negatively correlated, in which the level of available N was highly significant (p <0.01) and the level of available P and organic matter were significant (p <0.05). Glomalin with the available P content was significantly positively correlated (p <0.01), and the available N and organic matter content were positively correlated, negatively correlated with pH. Soil factors on the mycorrhizal infection rate for the direct effect: pH> available P> organic matter> available N, pH and available P played a major role. Soil factors on AMF species for the direct effect:organic matter> pH> available P> available N, organic matter and pH played a major role. The direct effect on glomalin content: available N> available P> organic matter> pH, but available P and pH indirect role in the main.4. The impact on growth of R.pseucdoacacia inoculated with AMF. Plants inoculated with AMF (G.mosseae, G.constrictum) were in contrast non-inoculated, single plant dry biomass increased 74.9% and 64.3%, stem diameter increased 36.8% and 26.3%, root activity increased 61.8% and 42.8%, Malondialdehyde reduced 27.1% and 30.6%, free proline reduced 46.1% and 35.7%, the activity of SOD increased 62.5% and 50%, the activity of CAT increased 218.6% and 131.7%, the activity of POD increased 152.8% and 90.4%, have reached significant difference (p <0.05). Compared to the two AM fungi, height and stem diameter no significant difference, dry biomass and root activity of G.mosseae was higher than G.constrictum, Significant difference (p <0.01), It is suggested that AM fungi can improve the capability of R.pseucdoacacia to scavenge the reactive oxygen, and enables R.pseucdoacacia to adapt soft rock soil environment, and G.mosseae was better for inoculation.5.The impact on the activity of soil enzymes in R.pseucdoacacia rhizosphere soil inoculated with AMF and Rhizobiums robinia. Compared with CK, inoculated with AMF in rhizosphere soil urease activity increased 1.5 times, Alkaline phosphatase activity increased 2.7 times, Invertase activity increased 2.0 times; Inoculated with Rhizobiums robinia in rhizosphere soil urease activity increased 1.9 times, Alkaline phosphatase activity increased 2.2 times, Invertase activity increased 1.4 times; Dual-inoculation in rhizosphere soil urease activity increased 3.4 times, Alkaline phosphatase activity increased 4.0 times, Invertase activity increased 2.9 times. The soil enzyme activity of inoculation was significantly higher than non-inoculation (p <0.05); the soil urease activity for the double-inoculation > Rhizobium> AMF; Alkaline phosphatase and Invertase activity for double-inoculation > AMF > Rhizobium; Dual inoculation was significantly higher than that of single inoculation (p <0.05), that can enhance the vitality of soil enzymes of Soft Rock.6.The impact on soil nutrients in R.pseucdoacacia rhizosphere soil inoculated with AMF and Rhizobiums robinia. Compared with CK, inoculated with AM fungi in rhizosphere soil available P reduced 2.78%, available N increased 6.36%, organic matter increased 4.78%; inoculated with Rhizobiums robinia in rhizosphere soil available P reduced 3.12%, available N increased 19.6%, organic matter increased 3.35%; Dual-inoculation in rhizosphere soil available P reduced 6.04%, available N increased 24.2%, organic matter increased 5.35%, glomalin increased 243.4%.All of inoculation has decreased soil pH, but the difference were small. Dual-inoculation of soil available nitrogen, organic matter content significantly compared to single inoculation significantly increased (p <0.05), nitrogen fixation of rhizobia and AMF in favor of the formation of the host phosphorus absorption strengthed each other.7. The impact on glomalin content in R.pseucdoacacia rhizosphere soil inoculated with AMF and Rhizobiums robinia. AMF inoculation and double inoculation than the non-inoculated control glomalin content increased 243.4% and 112.2%, Significant difference (p <0.05). AMF inoculation and double inoculation were much higher than the wild R.pseucdoacacia, description inoculated AMF and dual inoculation can improve the contents of glomalin. Glomalin had positive correlation with the activity of soil enzyme, available N, organic matter and single plant growth, but had negative correlation with available P and pH. It suggested that content of glomalin in rhizosphere soil could reflect soil restoration, in other words, the more glomalin, the better soil restoration. So advised that we could impose adequate nitrogen fertilizer, AMF inoculation and Rhizobium inoculation at the same time will effectively increase glomalin content, improved soil quality in soft rock zone.更多还原