5,6α-环氧-16-孕甾烯酮的生物转化研究

首次以绿色木霉对5,6α-环氧-16-脱氢孕甾酮的生物转化进行了研究,得到了15β羟基化的多羟基甾体新化合物3β,5α,6β,15β-四羟基-16-孕甾烯酮。试验结果表明:以初始pH值6.5的马铃薯汁培养基进行菌种培养,在菌种生长40h后加入0.1%底物,发酵时间为4d,温度27℃,3β,5α,6β,15β-四羟基-16-孕甾烯酮的收率最高。     

绿色木霉菌固体发酵培养基优化组合正交筛选

以测定绿色木霉菌产孢量和分生孢子萌发率为指标,分析比较了5种单一固体培养基和7种一般组合固体培养基的发酵结果,初筛出单一培养基玉米碎粒、稻壳和麸皮以及一般组合培养基玉米碎粒+麸皮+稻壳+脲为基本培养基。在此基础上选取玉米碎粒、麸皮、稻壳、脲为4个组分因子进行不同配比的正交试验,筛选出6号为最佳组合配方,其分生孢子量最高为9.90×10¹⁰个/g,比初筛出的最佳基本培养基麸皮+脲(3.37×10¹⁰个/g)提高约3倍,孢子萌发率为95.01%。     

食用菌绿色木霉及湿泡病高效杀菌剂配方筛选

选用具有低毒广谱性农药—福美双,百菌清(简称福.百)两单剂之间不同配比的组合,对绿色木霉和湿孢病菌进行室内毒力测试,从中筛选具增效配比组合作为防治食用菌绿色木霉和湿孢病的有效药剂。通过试验选定具有增效作用的配比组合—福美双和百菌清以18∶12的比例复配形成30%福.百可湿性粉剂(商品名菇丰),作为食用菌栽培过程中防治绿色木霉和湿孢病的杀菌剂。     

Effects of Host and Microbial Factors on Development of Clonostachys rosea and Control of Botrytis cinerea in Rose

Development of Clonostachys rosea in rose leaves and petals and control of Botrytis cinerea by the agent were investigated. C. rosea germinated, established endophytic growth, and sporulated abundantly whether the tissues were mature, senescent or dead when inoculated. Germination incidence was moderate on mature and senescent leaves (47% and 35%) and petals (31% and 43%), and high (>98%) on dead tissues. Sporulation of C. rosea in tissues inoculated when mature, senescent or dead averaged 41%, 61%, and 75% in leaves, and 48%, 87% and 53% in petals. When leaves were wounded with needles before inoculation, germination of C. rosea increased from 45–56% to 90–92%, but sporulation became high (>75%) regardless of wounds. When leaves were inoculated with C. rosea at 0–24h after wounding and subsequently with B. cinerea, germination of the pathogen was reduced by 25–41% and sporulation by 99%. A humid period prior to inoculation of senescent or dead leaves promoted communities of indigenous fungi, reduced sporulation of C. rosea and B. cinerea, and, in dead leaves, increased control of the pathogen associated with C. rosea. Applied at high density, isolates of indigenous Penicillium sp. and Alternaria alternata from rose interacted with C. rosea and reduced control of the pathogen by 16% and 21%, respectively. In conclusion, C. rosea markedly suppressed sporulation of B. cinerea in rose leaves and petals regardless of developmental stage, minor wounds, and natural densities of microflora. This versatility should allow C. rosea to effectively control inoculum production of B. cinerea in rose production systems.     

Field assessment of composts produced by highly effective cellulolytic microorganisms

 In a newly cultivated sandy soil, sugar beet haulms composted by highly effective cellulose-decomposing microorganisms (Trichoderma viride NRC6 or Streptomyces aureofaciens NRC22) were evaluated as organic manure for tomato plants (Lycopersicon esculentum L. cv. Supermarmment). The treatments were as follows: (1) control with NPK, (2) farmyard manure (FYM), (3) uninoculated compost, (4) compost inoculated with Glomus sp. NRC212, (5) compost produced by T. viride NRC6, (6) compost produced by S. aureofaciens NRC22. The organic amendments differed in their effects on total microbial counts in the rhizosphere of tomato plants. However, the amendment of soil with compost produced by highly effective cellulose-decomposing microorganisms or compost inoculated with arbuscular mycorrhizal (AM) fungi decreased the proliferation of the total bacteria in the rhizosphere of tomato plants compared with FYM or compost. The application of compost produced by T. viride NRC6 or S. aureofaciens NRC22 enriched the rhizosphere with fungi or Streptomyces more than the other manure treatments. FYM and compost enhanced both spore production and the percentage of mycorrhizal root infection of tomato plants as compared with the NPK treatment, while compost produced by T. viride NRC6 or S. aureofaciens NRC22 reduced both the mycorrhizal spore numbers and the percentage of mycorrhizal root infection as compared with the NPK treatment. However, the application of FYM or compost reduced the incidence of root rot by 8% and 32%, respectively, as compared with the NPK treatment. The use of T. viride NRC6 or S. aureofaciens NRC22 as cellulolytic microorganisms and AM fungi as inocula in the applied compost increased plant protection by 80%, 75%, and 73%, as compared with the NPK treatment, respectively. No significant differences in plant dry weight, N, P content and tomato yield were obtained between FYM and the mineral fertilizer treatment. However, different types of compost induced a significant increase in plant dry matter, N and P uptake and fruit yield relative to the FYM and mineral fertilizer treatments. Received: 17 February 1999     

Biological Seed Treatment of Cereals with Fresh and Long-term Stored Formulations of Clonostachys rosea: Biocontrol Efficacy Against Fusarium culmorum

In six field experiments, seed treatment with Clonostachys rosea (IK726) significantly reduced disease caused by Fusarium culmorum. IK726 was active against the pathogen at average soil temperatures at sowing ranging from 6.2 to 12 °C. Both in the field experiments and in growth chamber experiments conducted in sand, dried and stored conidia of IK726 controlled F. culmorum as effectively as freshly harvested conidia. A high correlation was found between disease index ratings from field experiments and from corresponding growth chamber sand tests. Amendment with the stickers Pelgel or Sepiret did not influence control activity. The effective dosages of IK726 (cfu/seed) were estimated in bioassays and were very similar for freshly harvested conidia and for dried conidia. With a density of > 5×10³ conidia per seed more than 80% disease control was repeatedly obtained with both types of conidia.     

几丁质和杀菌剂对生物防治菌生长及其防治棉花病害效果的影响

 研究了化学杀菌剂对木霉菌生长的影响,探讨了几丁质添加物对绿色木霉菌菌株L R、LTR-2、哈茨木霉菌菌株Q1、Q2和粉红粘帚霉菌菌株GLR防治棉花病害效果的影响。多菌灵、苯菌灵和甲基硫菌灵在1.66μg/ml时可以完全抑制Q1和Q2的生长,但在2.68μg/ml时才能完全抑制LR和LTR-2的生长。几丁质添加物使L TR-2和Q1防治棉花立枯病的效果完全丧失,但是能使LR从没有防治效果提高到防治效果为34.6%,而对粉红粘帚霉菌的防治效果没有显著影响;对于防治棉花黄萎病来说,几丁质添加物使木霉菌LR、LTR-2和GLR的防治效果降低,但是提高了Q1的防治效果;对于防治棉花枯萎病来说,几丁质添加物能提高所有测定菌株的防治效果。说明不同的生物防治菌株、添加物和病害组合对于获得良好的防治效果是重要的。     

绿色木霉应用的研究进展

绿色木霉(Trichoderma viride)产生的高活性纤维素酶广泛应用于开发纤维素资源,本文主要综述了绿色木霉的降解功能、在生物防治中的应用及其它作用的研究进展。     

绿色木霉固体发酵产孢子的条件优化

为研究工业生产中利用廉价的原料发酵绿色木霉生产孢子的问题,以稻壳粉、麦麸及玉米粉为主要载体,对影响绿色木霉固态发酵产孢子的条件进行筛选,并通过单因素试验研究固体载体的比例、碳源、氮源、无机盐对绿色木霉固态发酵产孢子的影响。通过4因素3水平正交试验,优化出最佳培养基配方。研究发现,绿色木霉固体发酵产孢子的最佳条件为温度28℃,接种量15%,料水比1:0.70,pH值自然;最佳培养基配方为麸皮50%,稻壳粉30%,玉米粉20%,硫酸铵1%,玉米浆干粉2%、黄豆饼粉2%、碳酸钙0.5%。发酵7天,孢子量可达7.62×10 ⁹个/g,自然晾干至水分10%以下,孢子量为1.286×10 ¹⁰个/g。     

木霉菌对松枯枝病的抑制作用

为探明绿色木霉和哈茨木霉的提取物对松枯枝病的抑制作用机制,通过绿色木霉（Trichoderma viride）和哈茨木霉（Trichoderma harzianum）提取物对松枯枝病病原菌（Cenangium ferruginosum Fr.）进行平板表面涂抹法和混合培养基法抑制生长试验,观察松枯枝病病原菌生长情况,结果表明,2种木霉菌的提取物对松枯枝病病原菌均有抑制作用,且效果比较明显,抑制效果最佳的为绿色木霉,病原菌的被抑制率达53.54%,混合培养基法中哈茨木霉菌20%提取物对枯枝病原菌的抑制率高达31.67%。