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91.
调查了海南八门湾8种红树植物根际丛枝菌根真菌物种资源的分布。结果表明:8种红树均被丛枝菌根真菌侵染,但侵染程度各不相同;经初步分离、鉴定,共确定丛枝菌根真菌4属16种:分别为无梗囊霉属(Acaulospora)6种,巨孢囊霉属(Gigaspora)2种,球囊霉属(Glomus)7种,Fuscutata 1种。其中球囊霉属和无梗囊霉属为优势属,首次在红树植物根际分离到巨孢囊霉属和Fuscutata两属真菌,Fuscutata savannicola为我国丛枝菌根真菌新记录种。  相似文献   
92.
我国大豆胞囊线虫生防真菌研究现状   总被引:3,自引:0,他引:3  
大豆胞囊线虫病(Heterodera glycines,SCN)在我国分布较广,危害较大,对该病的防治主要通过应用化学药剂,但化学药剂对人、畜不安全,对环境污染重[1]。目前,我国对大豆胞囊线虫生防真菌已有了大量的研究,本文综述了我国大豆胞囊线虫生防真菌的主要研究种类和数量、捕食性真菌和机会真菌的作用机制及生防制剂的田间应用、防效等情况。  相似文献   
93.
为研究茯砖茶发花过程中真菌群落的结构和种类,对茯砖茶渥堆发酵过程中不同时间段黑毛茶样品中真菌群落的18S rDNA高变区进行扩增,对真菌18S rDNA变性梯度凝胶电脉(DGGE)图谱中的条带进行回收、克隆、测序和序列比对。结果表明:茯砖茶渥堆发酵过程中的真菌类型丰富,有好干性酵母(Wallemia sebi)、假丝酵母菌(Candida sp.)、热带假丝酵母(Candida tropicalis)、路德酵母(Lodderomyces sp.)、汉逊德巴利酵母(Debaryomyces hansenii)、毕赤酵母(Pichia kudriavzevii)、酿酒酵母(Saccharomyces cerevisiae)、隐球酵母(Cryptococcus sp.)、牧草红酵母(Rhodotorula graminis)、阿姆斯特丹散囊菌(Eurotium amstelodami)、灰绿曲霉(Aspergillus glaucus)、米赫根毛霉(Rhizomucor miehei)、微小根毛霉(Rhizomucor pusillus)、白地霉(Galactomyces geotrichum)、安大略假单胞菌(Candida ontarioensis)、真皮毛孢子菌(Trichosporon dermatis)、斜卧青霉(Penicillium decumbens)、曲霉(Aspergillus penicillioides)等真菌存在;以渥堆24 h为分界点,真菌群落结构在分界点前后变化较大;真菌群落多样性指数在渥堆0~16 h呈升高趋势,16~24 h略有降低,24 h后继续升高,在渥堆后40 h上升到最高水平2.348,而渥堆40~48 h仍然维持在较高水平;在整个渥堆过程中,优势菌路德酵母、汉逊德巴利酵母和次优势菌阿姆斯特丹散囊菌均有出现,在渥堆后期出现了次优势菌好干性酵母、汉逊德巴利酵母和酿酒酵母;比对结果表明,渥堆过程中同时存在3株好干性酵母菌和7株阿姆斯特丹散囊菌,说明在渥堆发酵过程中优势菌种存在多样性。本研究结果表明,采用DGGE指纹图谱能全面、真实地反映茯砖茶渥堆发酵过程中真菌群落的结构和多样性变化。  相似文献   
94.
玉米茎腐病病原菌致病性及侵染规律的研究   总被引:8,自引:1,他引:8  
利用禾谷镰刀菌(Fusarium graminearum)、禾生腐霉菌(Pythium graminicola)和链状腐霉菌(Pythium catenulatum)3种玉米茎腐病的病原菌通过两年的试验进行了对玉米抗病品种和感病品种的致病性和侵染规律的研究。结果表明:在大田自然条件下,3种病原菌对玉米植株均有致病性.其中以禾谷镰刀菌的致病性最强,其次是禾生腐霉菌和链状腐霉菌。禾谷镰刀菌和腐霉菌在植株散粉盛期以前的侵染规律符合苗期致病性试验的结果。二者侵染致病作用的  相似文献   
95.
采用体外法研究了不同精粗比底物下(A组为全粗料,B组3∶7,C组5∶5,D组7∶3,E组为全精料)瘤胃真菌发酵特性及其对粗饲料(稻草秸)的附着情况。发酵试验结果表明:随底物精料比例的增加,同一时间点真菌数量呈上升趋势,A组到E组发酵96 h的累计产气量显著上升,分别为177.2 mL、198.2 mL、217.4 mL2、33.4 mL和251.5 mL,提示底物中精料比例的增加能促进瘤胃真菌的生长和发酵。此外,随底物精料比例的增加,羧甲基纤维素酶和α-淀粉酶酶活呈上升趋势,木聚糖酶酶活则呈下降趋势。稻草秸附着结果表明:不同发酵时期底物精粗比对附着于稻草秸的瘤胃真菌数量有很大影响。发酵前期(24 h),精料组(B组、C组和D组)附着于稻草秸表面的真菌孢子囊数显著高于粗料组(A组)。发酵后期(72 h),A组和B组附着于稻草秸表面和切缘的孢子囊数高于C组和D组,A组和B组附着于稻草秸表面和切缘的孢子囊数与48 h相比无显著变化,而C组和D组附着于稻草秸表面和切缘的孢子囊数显著下降。这种附着差异可能与不同精粗比底物提供的能量和附着位点不同有关。  相似文献   
96.
通过对陕西省武功县3个葛藤品种根区AM真菌的调查,初步探明了葛藤根区AM真菌资源,为AM真菌在葛藤上的应用提供理论依据。结果表明:AM真菌能与葛藤形成良好的共生关系,不同品种葛藤具有不同的AM真菌生长特性,其定殖率也不相同。总定殖率、泡囊、菌丝定殖率在品种间为:菜葛>粉葛>药葛;丛枝定殖率在品种间为粉葛>药葛>菜葛;孢子密度在品种间为:药葛>粉葛>菜葛。葛藤根区AM真菌资源丰富,土样中AM真菌多为球囊霉属(Glomus),也有少数无梗囊霉属(Acaulospora)和盾巨囊霉属(Scutellospora)的种类。已鉴定出AM真菌20种,其中球囊霉属13种,无梗囊霉属6种,盾巨囊霉属1种。  相似文献   
97.
丛枝菌根(Arbuscular mycorrhizal,AM)真菌对辣椒疫病等土传病害具有生防潜力,但由于难以纯培养而未能实现规模化生产应用,如能调动土著AM真菌的抑病功能则对实际生产具有重要指导意义。依托重庆石柱辣椒科技园,研究设施大棚中间作玉米对土著AM真菌生长及辣椒疫病防治的影响。结果表明,与辣椒单作相比,间作玉米处理辣椒根系AM真菌侵染率、根际AM真菌数量与土壤磷酸酶活性以及小区作物养分总吸收量均显著提高,辣椒疫病发病率与病情指数、单株辣椒的磷吸收量及果实生物量均显著下降,其中种植密度更高的等垄宽间作处理两种作物根系AM真菌侵染率、小区玉米产量及作物养分总吸收量均显著高于等行距间作处理,辣椒疫病发病率与之正好相反。设施环境下间作玉米或能通过促进AM真菌生长及其对辣椒根系的侵染来增强其对辣椒疫病的防治功效,其中等垄宽间作处理具有更好的经济效益。  相似文献   
98.
In terrestrial ecosystems, plants are frequently in symbiosis with arbuscular mycorrhizal fungi (AMF) with mineral nutrients and photosynthesis carbon exchanges in between. This research sought to identify the effects of phosphorus (P) levels on the nitrogen (N) uptake via extraradical mycelium (ERM) and the mycorrhizal growth response (MGR) of maize plants within the AMF symbiosis. Pots were separated into root compartments and hyphae compartments (HCs) with two layers of a 30‐μm mesh membrane and an air gap in between, where only hyphae could pass through, to avoid both N diffusion and root growth effects. Maize plants were inoculated with Rhizophagus irregularis with different N fertilization in HCs under two different P fertilization levels. Our results indicated that a strong increase in MGR with low‐P fertilization. The same tendency was not observed with high‐P fertilization, although both had a large increase in P concentration as a potential source of growth in shoot tissue of mycorrhizal plants. Substantial effects (10.5% more N) were observed in the case of high‐P availability for the host plants from ERM fed with N, whereas under low‐P conditions ERM may prioritize P uptake rather than N uptake. The AM fungi increase the uptake of N and P, which are most limiting in the soil with fewer forces from soil resources. In addition, there was still more P accumulated than N due to the high N for ERM with high‐P supply. Low N in HCs corresponded with a lower colonization rate in roots but with high hyphae density in HCs; this result suggest that N and P availability might change the ratio of extraradical to intraradical hyphae length.  相似文献   
99.
The aim of this work was to study the effect of arbuscular mycorrhizal fungus Glomus mosseae on growth and nitrogen (N) metabolism of durum wheat (Tritcum durum) under various P soil contents. The analyses were extended to macro and micronutrient tissue concentrations, nitrate reductase and glutamine synthetase activities, as well as protein, aminoacids, pyridine dinucleotides and adenine nucleotides. Arbuscular mycorrhiza increased wheat growth in soil in which P availability was low and nitrate was the dominant N form. The root colonization occurred at the highest level in plants grown in limiting soil P and was inversely related to soil P content. The micorrhizal wheat plants contained also the highest concentrations of macro (P, K, Ca, N) and micronutrients (Fe, Zn, Mn) as well as free amino acids, protein, NAD, NADP, AMP, ADP, ATP in roots and leaves. In particular, the micronutrient tissue concentrations (Zn, Mn) supported that mycorrhiza actively modulated their uptake limiting interferences and optimizing growth better than the plant roots, like a very efficient “rootstock”. Control plants grown at the highest soil P did not reach the same concentration as the mycorrhizal plants. Nitrate reductase activities in the roots of mycorrhizal plants were higher than in the control ones, while glutamine synthetase activities were highest in the leaves. Protein and amino acids concentrations, as well as AMP, ADP, ATP, NAD(P), and NAD(P)H were also higher than in the control. Among the free amino acids in the roots, the high levels of glutamine, asparagine, arginine, support the view that ammonium was transferred through the arbuscules to the root cells where it was re‐assimilated in the cortical cells, forming high N : C ratio‐amino acids. They were transferred to the leaves where all the other N compounds could be largely synthesized using the carbon skeletons supplied by photosynthesis.  相似文献   
100.
In the present study, the effects of inoculation of biofertilizers (phosphorus-solubilizing arbuscular mycorrhizal (AM) fungi (AMF), Glomus intraradices, and potassium-mobilizing bacterium (KMB), Frateuria aurantia) in combination with chemical fertilizers nitrogen, phosphorus, and potassium (NPK) on growth, yield, nutrient acquisition, and quality of tobacco were observed in pot culture. Factorial combinations of biofertilizers (AMF and KMB) and chemical fertilizer (NPK) alone and in combination were applied to see the effects on growth, biomass, nutrient acquisition, and leaf quality in tobacco. Results showed that bioinocula applied either singly or in combination did not significantly enhance soil availability of P and K, indicating their unsuitability for direct application. Application of chemical fertilizer in combination with both AMF and KMB strains consistently increased availability of P and K in the soil, improved leaf quality parameters, and enhanced plant growth and vigor, suggesting the potential use of AMF and KMB as biofertilizers in sustainable tobacco crop production.  相似文献   
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