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111.
The nematodes, Pratylenchus brachyurus, Trichodorus christiei, and T. porosus and the soil-borne fungi, Rhizoctonia solani, Pythium debaryanum, P. irregulare, P. ultimum, and Fusarium spp. were the pathogens most frequently found in the roots and rhizosphere of field-grown cotton (Gossypium hirsutum) showing "stunt" symptoms. Field-plot application of the nematicide D-D (l,2-dichloropropane, 1,3-dichloropropene) at 373.4 liter/ha (40 gal/A) significantly increased plant growth and yield. A fungicidal mixture of Dexon (p-dimethylaminobenzenediazo sodium sulfonate at 23.5 kg/ha (2l lb/A) and Terraclor (pentachloronitrobenzene at 25.2 kg/ha (22.5 lb/A) was phytotoxic, but combined nematicide/fungicide treatments were not. Greenhouse temperature-tank experiments in soils from two locations showed significantly improved root and shoot growth following methyl bromide fumigation at both 25 C and 18 C and more severe "stunt" at the lower temperature. 相似文献
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113.
Bio‐preparation of (R)‐DMPM using whole cells of Pseudochrobactrum asaccharolyticum WZZ003 and its application on kilogram‐scale synthesis of fungicide (R)‐metalaxyl 下载免费PDF全文
Yinjun Zhang Yicheng Fan Wei Zhang Guanzhong Wu Jinghong Wang Feng Cheng Jianyong Zheng Zhao Wang 《Biotechnology progress》2018,34(4):921-928
Methyl (R)‐N‐(2,6‐dimethylphenyl)alaninate ((R)‐DMPM) is a key chiral intermediate for the production of (R)‐metalaxyl, which is one of the best‐selling fungicides. A new strain, Pseudochrobactrum asaccharolyticum WZZ003, was identified as a biocatalyst for the enantioselective hydrolysis of (R,S)‐DMPM. The key parameters including pH, temperature, rotation speed and substrate concentrations were optimized in the enantioselective hydrolysis of (R,S)‐DMPM. After the 48 h hydrolysis of 256 mM (R,S)‐DMPM under the optimized reaction conditions, the enantiomeric excess of product (e.e.p) was up to 99% and the conversion was nearly 50%. Subsequently, the unhydrolyzed (S)‐DMPM was converted to (R,S)‐DMPM through the n‐butanal‐catalyzed racemization. Furthermore, stereoselective hydrolysis of (R,S)‐DMPM catalyzed by whole cells of P. asaccharolyticum WZZ003 was scaled up to kilogram‐scale, offering (R)‐MAP‐acid with 98.6% e.e.p and 48.0% yield. Moreover, (R)‐metalaxyl was prepared at kilogram scale after subsequent esterification and coupling reactions. Therefore, a practical production process of (R)‐DMPM and (R)‐metalaxyl with the prospect of industrialization was developed in this study. © 2018 American Institute of Chemical Engineers Biotechnol. Prog., 34:921–928, 2018 相似文献
114.
用真菌β-微管蛋白基因的丰余寡聚核着酸引物B1和B3,扩增了一段871bp的水稻恶苗病菌Fusariummoniliforme的β微管蛋白基因片段,进行了克隆和DNA序列测定,并根据该序列设计了Fmoniliformeβ-微管蛋白基因的特异性测序引物。经过对恶苗病菌对多菌灵具有不同抗性水平菌株的β-微管蛋白基因核着酸序的比较研究,表明Fmoniliforme的β微管蛋白的165,198,200和257位置氨基酸末发生突变,在克隆的片段内也未发现能引起氨基酸改变的核着酸突变。说明该菌对多菌灵产生抗性的分子机理与目前已知的其他真菌有所不同,有待进~步研究。 相似文献
115.
强力安对食用菌生产中杂菌的毒力测定 总被引:3,自引:1,他引:2
试验利用滤纸片、管碟抑菌圈法测定了强力安杀菌剂对木霉TrichodermaviridePers.exFr、链孢霉MoniliasitophilaMont等食用菌生产上的杂菌的毒力,结果表明强力安具有明显的抑菌、杀菌作用。试验还测定了强力安对食用菌的作用,结果表明强力安对平菇Pleurotusostreatus(JacexFr)Quel、金针菇Flammulinavelutipes(Fr)Sing具抑制力,而对黑木耳Auriculariaauricula(l.exHook)Underw、香菇Lentinulaedodes(Berk)Pegler则未发现抑制作用。根据强力安对供试菌的最低抑制浓度,作者提出了生产实际上的用药浓度,以供参考。 相似文献
116.
Chemotaxonomic study of seed glucosinolate composition in Coincya Rouy (Brassicaceae) 总被引:1,自引:0,他引:1
JAVIER VIOQUE JULIO E. PASTOR MANUEL ALAIZ EDUARDO VIOQUE 《Botanical journal of the Linnean Society. Linnean Society of London》1994,116(4):343-350
A total of 68 populations belonging to the genus Coincya Rouy (Brassicaceae) from the Iberian Peninsula was examined for seed glucosinolate composition. The presence of progoitrin, epiprogoitrin, glucosinalbin and gluconapin was recorded plus a fifth glucosinolate that could not be identified. A geographical clinal variation between progoitrin and epiprogoitrin was observed in the more widespread taxa, C. monensis subsp. orophila (Franco) Aedo, Leadiay & Murioz Garm. and C. moncnsis subsp. cheiranthos var. recurvata (All.) Leadiay. The fewest types of glucosinatc were observed in taxa with morphological characters considered more primitive, viz. subsp. hispida and var. recurvata. On the other hand, more complex and diverse composition was observed in the taxon with more advanced characters, viz. C. rupestris subsp. rupestris Porta & Rigo. 相似文献
117.
Development and application of a simple,rapid and sensitive method for detecting moderately carbendazim‐resistant isolates in Botrytis cinerea 下载免费PDF全文
Y.B. Duan Y. Yang M.X. Li T. Li B.A. Fraaije M.G. Zhou 《The Annals of applied biology》2018,172(3):355-365
Sustainable disease management depends on the ability to monitor the development of fungicide resistance in pathogen populations. A point mutation resulting in an alteration (F200Y) at codon 200 of the target protein β‐tubulin leads to a moderate level of resistance to carbendazim in Botrytis cinerea. Although traditional methods remain a cornerstone in detection of fungicide resistance, molecular methods that do not require the isolation of pathogens, can detect the presence of resistance alleles at low frequencies, and require less time and labour than traditional methods. In this study, we present an efficient, rapid, and highly specific method for detecting the moderately carbendazim‐resistant isolates in B. cinerea based on loop‐mediated isothermal amplification (LAMP). By using specific LAMP primers, we detected the resistance‐conferring mutation underlying β‐tubulin F200Y. The concentrations of LAMP components and LAMP parameters were optimised, resulting in reaction temperatures and times of 61–65°C and 45 min, respectively. The feasibility of the LAMP assay was verified by assaying the diseased samples with artificial inoculation in the different hosts. The LAMP assay developed in the current study was specific, stable, repeatable and sensitive, and was successfully applied for detection of moderately carbendazim‐resistant isolates of B. cinerea in plant samples. 相似文献
118.
Carbendazim resistance and dimethachlone sensitivity of field isolates of Sclerotinia sclerotiorum from oilseed rape in Henan Province,China 下载免费PDF全文
Shengming Liu Jia Jiang Zhiping Che Yuee Tian Genqiang Chen 《Journal of Phytopathology》2018,166(10):701-708
Sclerotinia stem rot caused by Sclerotinia sclerotiorum is one of the most important diseases in oilseed rape‐growing areas of China. To determine the frequency of resistance of field isolates of S. sclerotiorum to carbendazim and dimethachlone, a total of 556 isolates from 10 different regions of Henan Province were obtained between 2015 and 2016. The frequency of isolates with a high‐resistance phenotype and a moderate‐resistance phenotype to carbendazim was 69.2% and 10.8%, respectively. However, S. sclerotiorum isolates resistant to dimethachlone were not detected. The baseline sensitivity of S. sclerotiorum to dimethachlone was distributed as a unimodal curve with a mean EC50 value of 0.39 ± 0.09 μg ml?1 for the inhibition of mycelial growth. Four dimethachlone‐resistant mutants were obtained from 20 wild‐type isolates induced by exposure to increasing concentrations of the fungicide in vitro. The mutants showed high levels of resistance to dimethachlone, with resistance factors that ranged from 179 to 323. Positive cross‐resistance occurred between dimethachlone and procymidone, iprodione, and fludioxonil; however, no cross‐resistance was observed for carbendazim and boscalid. The fitness of the dimethachlone‐resistant mutants was significantly lower than that of the wild‐type isolates, as measured by mycelial growth, hyphal dry weight, sclerotium number and dry weight, and pathogenicity. Additionally, based on osmotic tests, the inhibition of mycelial growth caused by NaCl applied at different concentrations was significantly higher for the dimethachlone‐resistant mutants than for their wild‐type parents. 相似文献
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120.
Monica R. Loizzo Mariangela Marrelli Alessandro Pugliese Filomena Conforti Farsad Nadjafi Francesco Menichini 《Journal of enzyme inhibition and medicinal chemistry》2016,31(2):212-218
Spices are appreciated for their medicinal properties besides their use as food adjuncts to enhance the sensory quality of food. In this study, Crocus cancellatus subsp. damascenus was investigated for its antioxidant activities employing different in vitro systems. Stigma extract demonstrated a radical scavenging activity against both 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) radicals with IC50 values of 34.6 and 21.6?µg/mL and a good ferric reducing ability (53.9?µM Fe(II)/g). In order to clarify the potential functional properties of this spice, the carbohydrate-hydrolysing enzymes and pancreatic lipase inhibitory properties were investigated. Crocus cancellatus subsp. damascenus extract inhibited α-amylase and α-glucosidase with IC50 values of 57.1 and 68.6?µg/mL, respectively. The bioactivity was discussed in terms of phytochemicals content. The obtained results may be of interest from a functional point of view or as food additive and to promote the revalorization of this species. 相似文献