苏云金芽孢杆菌芽孢萌发相关基因gerM的克隆及功能研究

采用土壤平板法和稀释平板法,自湖北神农架自然保护区的14份土壤样品中分离得到40个暗色丝孢菌分离物,鉴定为16属23种。其中,湖北弯孢Curvularia hubeiensis为一新种,嗜热革节孢Scytalidium thermophilum和禾色串孢Torula graminis为中国新记录种。对新种及中国新记录种作了详细的描述。其余20种为国内已报道种。所有研究菌株的干制培养物标本与活菌种均存放在山东农业大学植物病理学标本室(HSAUP)。     

Microbial hydroxylation of 16α,17α-dimethyl-17β-(l-oxopropyl)androsta-l,4-dien-3-one to rimexolone by Curvularia lunata AS 3.4381

A novel synthetic route to rimexolone, a corticosteroid for treatment of ocular inflammation without significant elevation of intraocular pressure, was described. An investigation has been undertaken of the microbial transformation of 16α,17α-dimethyl-17β-(l-oxopropyl)androsta-l,4-dien-3-one by microorganisms known to hydroxylate conventional steroids, using Curvularia lunata AS 3.4381 gave rimexolone, the product of 11β-hydroxylation, respectively. The target compound was characterized with reference substance rimexolone by TLC, HPLC, elemental analysis, MS, IR, and NMR.     

不等弯孢菌HS-FG-257中一个新的苯甲酸类化合物(英文)

从土壤不等弯孢菌HS-FG-257中分离得到4个化合物,通过波谱学鉴定为4-hydroxy-3-(3-methyoxy-3-methylbutyl)-benzoic acid(1),4-hydroxy-3-(3-hydroxy-3-methylbutyl)-benzoic acid(2),4-hydroxy-3-prenylbenzoicacid(3)and radicinin(4),其中化合物1为新化合物。     

中国东部暖温带地区土壤中的蠕形菌

在调查研究中国东部暖温带地区土壤中暗色丝孢菌过程中,采用稀释平板法和土壤颗粒平板法分离获得100余株蠕形菌的分离物。经纯化培养后,依据形态特征鉴定为3属21种,其中虎尾草平脐蠕孢[Bipolaris chlorides (Alcon) Alcon]和小柄凸脐蠕孢[Exserohilum pedicellatum (Henry) Leonard & Suggs]为中国新记录种。文中列出了各蠕形菌的种名、采集地、土样号以及菌株号,对2个新记录种进行了详细描述。所有活菌株及干制培养物保存在山东农业大学植物病理系标本室(HSAUP)。     

Enhancement of 17alpha-hydroxyprogesterone production from progesterone by biotransformation using hydroxypropyl-beta-cyclodextrin complexation technique

An enhancement of 17α-hydroxyprogesterone (17α-HP) production from progesterone by biotransformation using hydroxypropyl-β-cyclodextrin (HPβCD) complexation together with aeration and sonication technique was demonstrated. The progesterone–hydroxypropyl-β-cyclodextrin complex was prepared by co-evaporation method. The percentage yield of 17α-HP from P of 11.26 ± 0.64% at 24 h was observed in Curvularia lunata ATCC 12017. In the complex form of P, together with sonication at 40 kHz for 5 s and aeration, the yield of 17α-HP was increased to 72.92 ± 4.28% which was about 6.5 and 1.3 times of that from the uncomplexed (P) and the complexed (PC), respectively without sonication and aeration. The increased aqueous solubility of P by complexation with HPβCD was the main factor which increased the yield of 17α-HP, while aeration had more effect on P than PC. Sonication did not significantly increased the yield of the product from both P and PC. When both aeration and sonication were used in the PC system, the product yield was increased significantly more than that from P. The result from this study can be applied for the biotransformation of other poor aqueous soluble precursors.     

Isolation, Pathogenicity and Safety of Curvularia eragrostidis Isolate QZ-2000 as a Bioherbicide Agent for Large Crabgrass (Digitaria sanguinalis)

A pathogen isolated from lesions on blighted leaves of crabgrass in three different locations of China was identified as Curvularia eragrostidis. Isolate QZ-2000 was the most virulent of six isolates tested. Experiments on morphology, pathogenicity, effect of environmental factors, and host-range of isolate QZ-2000 were conducted in the laboratory, greenhouse and field to assess the potential of this isolate as a biocontrol agent for grassy weeds. Pathogenicity was quantitatively determined based on mortality and dry-weight reduction of infected large crabgrass. Inoculum concentration, rapeseed oil concentration in formulaton, post-inoculation dew temperature and duration, and plant growth age all significantly influenced the efficacy of the isolate. A total of 85-100% control of large crabgrass was obtained when inoculum concentrations were ≥1×10⁶ conidia mL^-1, oil concentrations ≥0.9% (v/v), dew period ≥24 h and air temperatures 20-30°C in the greenhouse. A total of 51 plant species in 20 families were screened against isolate QZ-2000 in host-range studies. Six other species of grassy weeds were susceptible to isolate QZ-2000, but no mortality or significant dry-weight reduction was observed for maize (Zea mays), rice (Oryza sativa), soya bean (Glycine max), cotton (Gossypium hirsutum), or any other economically important crops and plants. In field trials, with 5×10⁶ conidia mL^-1 inoculum density, 60-7% reduction in dry weight was achieved for large crabgrass seedlings under natural dew-free conditions. These results indicate that isolate QZ-2000 is a potential microbial bioherbicide for control of large crabgrass in crops such as corn, soybean, cotton, water-melon, and peanut.     

弯孢属一新种

本文报道生于大叶仙茅Curculigo capitulata上的一弯孢属Curvularia新种:仙茅弯孢Curvularia curculiginis。新种的模式标本保藏于山东农业大学植物病理标本室(HSAUSP)。     

Studies on inhibitory activities of antibodies against phytopathogenic fungi: an immunological approach

The major problem in agriculture is that of the fungal pathogens. In this era, where biological control is at focus, and is the centre of crop protection as well as environmental protection, the synthesis of new bio bodies is of utmost need. Fungicides available in the market, though of potential, are pathogen specific and highly pollutive. An attempt was made to raise polyclonal antibodies against Aspergillus niger. Following the particular standardised immunisation schedule, regular injections and periodic tapping were carried out. The IgG purified was used to check cross-reactivity with different crop fungi like Fusarium solani, Fusarium oxysporum f. sp. cicer (FOC), Rhizoctonia bataticola, Botryodiplodia theobromae, Curvularia sp., Alternaria porri and also with Aspergillus niger by two different methods. Liquid test media and the radial growth inhibition test performed in solid media were used to check the inhibition of fungi and cross-reactivity. The results were subjected to analysis of variance (ANOVA) by using Tukey's test at the significance level of p < 0.05. The antibodies were active against all the fungi for more than 15 days except for A. niger in which from the seventh day onwards spore germination was observed. The probable role of antibodies to detect the common antigenic molecule that may be present in all the tested fungi and their role in inhibiting these fungi is discussed.     

Greenhouse screening ofTrichoderma isolates for control ofCurvularia leaf spot of yam

TenTrichoderma isolates were studied under greenhouse conditions as potential agents for biocontrol of yam leaf spot, caused byCurvularia eragrostidis. TheTrichoderma isolates demonstrated high efficiency of disease control. Application of the antagonists on the same day asC. eragrostidis inoculation showed the best results. One isolate achieved 75 percent disease severity reduction. The survival of theTrichoderma isolates decreased after its application on the phylloplane with values of 57 and 41 percent at the 49th day, in the absence and presence of the phytopathogen respectively. The antagonism persisted well againstC. eragrostidis, the TN1 isolate praises 89 percent.     

Proteomics Associated with Virulence Differentiation of Curvularia lunata in Maize in China

One-dimensional electrophoresis (1-DE) of proteins, two-dimensional electrophoresis (2-DE) of proteins and cloning of cDNA sequence were used to study the virulence differentiation of Curvularia lunata (Wakker) Boed. isolated from maize (Zea maydis L.) in China. From 1-DE gel profiles of proteins, 110 reproducible bands were separated from six isolates of C. lunata CX-3, SD-6, C-152, C107-1, DD-60 and W-18. Sixty-eight bands (61.82%) were polymorphic,suggesting huge biodiversities among the isolates. All isolates for the experiment were clustered into three groups consisting of different virulent types by coefficient value of 0.605. Group 1, consisting of CX-3, SD-6 and C-152 with high virulence displayed more protein bands than Groups 2 and 3, consisting of C107-1 and DD-60 with low virulence. Proteomics approaches based on 2-DE techniques were applied to identify specific proteins associated with the virulence differentiation in CX-3 and DD-60. A total of 423 protein spots were separated. Out of them 75 specific protein spots were displayed in 2-DE gels. Among them 28 protein spots were unique in CX-3 and eight in DD-60, and 39 protein spots were shown on both 2-DE gels but expressed differently in intensity. Twenty protein spots including three unique protein spots and 17 differentially expressed protein spots (more than two-fold DD-60) in CX-3 were further identified with MALDI-TOF MS/MS. Results indicated that most of the identified proteins were found to be associated with virulence differentiation, metabolisms, stress response and signal transduction.One of them was identified as Brn1 protein, which had been reported to be related to melanin biosynthesis and the virulence differentiation in fungi. Combined with our previous findings, we assumed that Brn1 protein and its regulating products might be involved in the virulence differentiation of C. lunata. Consequently, we cloned a Brn1 cDNA fragment and aligned it with the fragments in other fungi. Results indicated that the 633-bp sequence of Brn1 cloned in C. lunata was highly homological with the compared fungi. Further work for the exact gene roles of Brn1 in our case is underway.