0.2%苦皮藤素乳油在土壤中的吸附与降解

测定了0.2%苦皮藤素乳油在土壤中的吸附、淋溶与降解行为。结果表明,苦皮藤素在土壤中能被较好的吸附;在小麦地、蔬菜地和水稻田土壤中的生物半衰期依次为199.75,167.43和165.43h。     

Effect of tebuconazole-tolerant and plant growth promoting Rhizobium isolate MRP1 on pea–Rhizobium symbiosis

Seed dressing with fungicides adversely affects the structure and function of beneficial soil microbial communities and consequently crop yield. This study was aimed to evaluate the impact of technical-grade fungicide tebuconazole on plant growth promoting potentials of tebuconazole-tolerant Rhizobium isolate MRP1. The performance of the isolate MRP1-inoculated pea plants grown in tebuconazole treated soils was also assessed. Generally, the three concentrations [100 (recommended dose), 200 and 300 μg kg⁻¹ soil] of tebuconazole when used alone, adversely affected the growth, symbiosis, grain yield and nutrient uptake by pea plants. Concentration dependent phytotoxicity of tebuconazole was observed for all the measured parameters. On the contrary, fungicide tolerant Rhizobium sp. MRP1 in the presence of fungicide increased the measured parameters at all tested concentrations. As an example, when inoculant MRP1 was also used with 300 μg tebuconazole kg⁻¹ soil, it substantially increased the root nitrogen, shoot nitrogen, root P, shoot P, seed yield and grain protein by 20, 19, 50, 31, 15 and 7%, respectively, when compared with uninoculated plants grown in fungicide-treated soils. The study suggests that the plant growth promoting Rhizobium sp. MRP1 can be used as bacterial inoculant to increase the production of pea in soils polluted with fungicides.     

7种杀菌剂对大麦条纹病的防治效果

针对大麦条纹病,选用7种杀菌剂对大麦品种甘啤4号种子处理后进行了室内毒力测定和室内发芽测定,同时进行了大田试验。结果表明,10％二硫氰基甲烷乳油,37／6敌萎丹悬浮种衣剂和0．5％二硫氰基甲烷种衣剂具有较好的抑菌效果,其EC。。有效抑菌浓度为2．563、7．345和19．721μg／mL;10％二硫氰基甲烷乳油、8％克...     

娘青核桃的生物学特性研究

以38 a生娘青核桃为试材,对其植物学特征和生物学特性进行了观测。结果表明:娘青核桃坚果为卵圆形,干果单粒重11.2 g,壳厚1.27 mm,取仁尚易,能取整仁或半仁。仁重5.7g,出仁率50.7%,种仁充实饱满、具有特殊的淡紫色或明显的紫色脉络、食味香甜、无涩味,含油率74%,是核桃仁精加工的优良地方品种。     

Taxonomy,distribution and biology of lettuce powdery mildew (Golovinomyces cichoracearum sensu stricto)

This paper reviews the taxonomy, biology, importance, host–pathogen interactions and control of lettuce powdery mildew. The main causal agent of this disease, Golovinomyces cichoracearum s.s., is an important powdery mildew pathogen of many members of the family Asteraceae. The pathogen is distributed worldwide and occurs on Lactuca sativa as well as wild Lactuca spp. and related taxa (e.g. Cichorium spp.). Powdery mildew of lettuce can be a major problem in production areas with favourable environmental conditions for disease development (dry, hot weather). The fungus grows ectophytically and appears as white, powdery growth on both the upper and lower sides of leaves. There is rather limited information on the geographic distribution of powdery mildew on wild Lactuca spp. Most L. sativa cultivars have been found to be susceptible. Large variability in virulence was confirmed and existence of different races is supposed. Resistance in L. sativa and some related wild Lactuca spp. is characterized by race‐specificity, but the genetic background of resistance is poorly understood. Sources of resistance are known in L. saligna and L. virosa. Lettuce powdery mildew can be effectively controlled by common fungicides (e.g. sulphur, myclobutanil, quinoline, strobilurins, etc.) and protective compounds (e.g. extract of neem oil, Reynoutria sachaliensis extracts). However, fungicide resistance may arise. Non‐fungicidal activators of plant systemic acquired resistance (SAR) had no direct effect on the causal agent. Future issues regarding lettuce powdery mildew research are summarized.     

浙江衢州地区柑橘绿霉病菌对抑霉唑和多菌灵的抗性水平及其分子机制

研究了采自浙江衢州地区,包括柯城区、衢江区和开化县12个贮藏库的70个柑橘绿霉病菌Penicillium digitatum菌株对抑霉唑和多菌灵的抗性频率、抗性水平及其抗性分子机制。结果表明:柯城区和衢江区的抑霉唑抗性菌株(最低抑制浓度MIC≥0.5 μg/mL)的比例分别为77.1%和62.5%,两地抗性菌株的平均EC50值分别为2.07±1.04 μg/mL和2.35±0.73 μg/mL,分别是当地敏感菌株EC50值的41.4和47.0倍;而采自开化县的菌株均对抑霉唑敏感(MIC≤0.1 μg/mL),平均EC50值为0.04±0.02 μg/mL。柯城区和衢江区的多菌灵抗性菌株(MIC≥10 μg/mL) 的比例分别为54.3%和54.2%,而开化县的抗性菌株比例仅为9.1%。即来自柯城和衢江两个柑橘主产区的绿霉病菌群体对抑霉唑和多菌灵的抗性频率均远高于非柑橘主产区的开化县群体,说明抗药性群体的形成与药剂使用历史有关。进一步研究发现,衢州地区柑橘绿霉病菌对抑霉唑的抗性均属于IMZ-R3型,即与抑霉唑靶标基因 CYP51B 启动子区的插入突变有关,而对多菌灵的抗性则与 β-微管蛋白基因的992位核苷酸点突变(T→A)导致对应的200位点的氨基酸突变(F→Y)有关。     

不同种植密度对青花菜植物学性状及产量的影响

调查不同种植密度对青花菜植物学性状及产量的影响,探寻适宜青花菜生长的合理密度,以达到增产的目的。     

草莓褐色轮斑病病原鉴定及室内药效研究*

草莓褐色轮斑病近年越来越严重,尤其在草莓育苗阶段。从草莓发病叶片、匍匐茎上分离得到病原菌,对病原菌进行形态特征观察、生物学特性研究、ITS序列分析以及室内药效试验。结果表明：该病原菌为Sphaeronaemella fragariae。该菌菌丝生长最适温度范围是25～28 ℃;适宜pH为6;在供试的几种碳、氮源中,最适的碳源是蔗糖,最适的氮源是酵母浸出液。在供试的9种药剂中,以咪鲜胺1 000倍液对病菌的抑制作用最好。     

Synthesis of new compounds related to the commercial fungicide tricyclazole

BACKGROUND: Tricyclazole is a commercial fungicide used to control rice blast. As part of re‐registration activities, samples of metabolites and process impurities are required. In addition, isotopically labeled tricyclazole samples are also required. RESULTS: Four new compounds related to tricyclazole are reported. An isotopically labeled sample of tricyclazole was prepared that contained two ¹⁵N atoms and one ¹³C atom. Radiolabeled tricyclazole with ¹⁴C at the triazole C3 position was also synthesized. A new process impurity in technical tricyclazole was identified and synthesized. A new metabolite of tricyclazole was identified, independently synthesized and characterized by X‐ray crystallography. CONCLUSION: A previously unreported metabolite of tricyclazole has been identified and structurally characterized. In addition, a new process impurity has been identified by independent synthesis. Identification of these new compounds has facilitated the continued registration of this important fungicide. Copyright © 2011 Society of Chemical Industry