几种杀菌剂对草霉灰霉病菌的室内毒力测定

在实验室条件下,采用室内菌丝生长速率法测定了6种杀菌剂对草莓灰霉病菌( Botrytis cinerea)的毒力。测定结果表明,咪鲜胺、多菌灵、速克灵、扑海因、烯唑醇和三唑酮对草莓灰霉病菌的EC50值分别为0.0233 mg/L、0.0421 mg/L、0.1724 mg/L、0.2837 mg/L 、0.3021 mg/L和0.3263 mg/L。其中,草莓灰霉病菌对咪鲜胺最敏感（EC50值为0.0233 mg/L）。     

藤仓赤霉菌的抗药性及对不同杀菌剂敏感性的相关分析

为探明江苏省藤仓赤霉菌(Gibberella fujikuroi)对多菌灵、咪鲜胺和氰烯菌酯的抗药性以及多菌灵与咪鲜胺对其他杀菌剂的交互抗性,采用区分剂量法分别检测了采自江苏省16个县(市)的202株藤仓赤霉菌对多菌灵、咪鲜胺和氰烯菌酯的抗药性,并采用菌丝生长速率法检测了对多菌灵与咪鲜胺不同敏感性的10个菌株对戊唑醇、灭菌唑、丙硫菌唑、叶菌唑、咯菌腈和氟啶胺等杀菌剂的敏感性。结果表明,藤仓赤霉菌对多菌灵、咪鲜胺和氰烯菌酯的抗性频率分别为77.72%、67.33%和0%。根据菌株对3种杀菌剂的抗药性表现,可分为4种表现型,其中对多菌灵和咪鲜胺抗药而对氰烯菌酯敏感的菌株占58.42%;对多菌灵抗药而对咪鲜胺和氰烯菌酯敏感的菌株占20.30%;对咪鲜胺抗药而对多菌灵和氰烯菌酯敏感的菌株占9.90%;对多菌灵、咪鲜胺和氰烯菌酯均敏感的菌株占11.39%。通过敏感性相关性分析,藤仓赤霉菌对多菌灵以及咪鲜胺和上述杀菌剂之间均无交互抗性。江苏省藤仓赤霉菌对多菌灵和咪鲜胺的抗性频率较高而对氰烯菌酯敏感,需要筛选新的杀菌剂防治水稻恶苗病。     

上海地区草莓灰霉病菌对啶酰菌胺的抗性水平及抗性频率较高

正为明确上海地区草莓灰霉病菌Botrytis cinerea Pers.对主要防治药剂啶酰菌胺的敏感性水平及抗性机制,上海市农科院生态环境保护研究所等单位科研人员采用平皿法检测了采自上海市6个区县的195株草莓灰霉病菌株对啶酰菌胺的敏感性,并分析了其中20株不同敏感型菌株的琥珀酸脱氢酶基因序列。结果显示,啶酰菌胺对上海地区草莓灰霉病菌菌丝生长的EC50     

2种常见番茄致病真菌对几种杀菌剂的敏感性测定

旨在筛选能同时有效抑制番茄早疫病菌和番茄晚疫病菌生长的杀菌剂。采用生长速率法测定了几种杀菌剂对供试病原菌的EC50值,并通过EC50值比较病原菌对供试杀菌剂的敏感性。结果表明：番茄早疫病菌对25%啶菌噁唑EC、25%咪鲜胺EC表现敏感,对50%腐霉利WP、0.3%丁子香酚SL和10%多抗霉素 B WP表现中抗;番茄晚疫病菌仅对25%啶菌噁唑EC表现敏感,对25%咪鲜胺EC、0.3%丁子香酚SL和10%多抗霉素B WP表现中抗,对50%腐霉利WP则表现高抗。2种病原菌对2×108 cfu/g绿色木霉菌WP和8×109 cfu/mL枯草芽孢杆菌AS较为敏感,EC50值均小于1×108 cfu/L。化学杀菌剂中啶菌噁唑,生物源杀菌剂中丁子香酚、绿色木霉菌和枯草芽孢杆菌对2种番茄致病真菌的抑菌效果较好的药剂,用量少且毒性低,可以在生产中推广使用。     

两种常见番茄致病真菌对几种杀菌剂的敏感性测定

旨在筛选能同时有效抑制番茄早疫病菌和番茄晚疫病菌生长的杀菌剂。采用生长速率法测定了几种杀菌剂对供试病原菌的EC50值,并通过EC50值比较病原菌对供试杀菌剂的敏感性。结果表明：番茄早疫病菌对25%啶菌噁唑EC、25%咪鲜胺EC表现敏感,对50%腐霉利WP、0.3%丁子香酚SL和10%多抗霉素B WP表现中抗;番茄晚疫病菌仅对25%啶菌噁唑EC表现敏感,对25%咪鲜胺EC、0.3%丁子香酚SL和10%多抗霉素B WP表现中抗,对50%腐霉利WP则表现高抗。2种病原菌对2×108 cfu/g绿色木霉菌WP和8×109 cfu/mL枯草芽孢杆菌AS较为敏感,EC50值均小于1×108 cfu/L。化学杀菌剂中啶菌噁唑,生物源杀菌剂中丁子香酚、绿色木霉菌和枯草芽孢杆菌对2种番茄致病真菌的抑菌效果较好的药剂,用量少且毒性低,可以在生产中推广使用。     

浙江省柑橘黑点病菌对代森锰锌、咪鲜胺、王铜、嘧菌酯和甲基硫菌灵的敏感性

为明确代森锰锌、咪鲜胺、王铜、嘧菌酯和甲基硫菌灵5种杀菌剂对柑橘黑点病菌敏感性,采用菌丝生长速率法测定浙江省不同地区43株黑点病菌株对5种杀菌剂的敏感性。结果表明,柑橘黑点病菌对代森锰锌、咪鲜胺、王铜、嘧菌酯和甲基硫菌灵的平均EC50值分别(4.0136±4.2897)、(0.0851±0.0325)、(179.2214±63.0787)、(0.1519±0.3377)、(0.6148±1.4194)μg/mL。Shapiro-Wilk检验结果表明,各杀菌剂的EC50值均呈正态分布,各杀菌剂的平均EC50值可作为对柑桔黑点病菌的敏感性基线。     

橡胶树棒孢霉落叶病苗圃防治初报

为了给田间筛选出防治橡胶树棒孢霉落叶病的高效药剂,对甲基硫菌灵、咪鲜胺锰盐、多菌灵、百菌清、咪鲜胺等5种杀菌剂在发病苗圃进行常规防治试验。结果表明：25%咪鲜胺乳油最好,2000倍液药后28天防效达到82.99%;75%百菌清可湿性粉剂次之,2000倍液药后28天防效达到78.20%;70%甲基硫菌灵可湿性粉剂、50%咪鲜胺锰盐可湿性粉剂、50%多菌灵可湿性粉剂的防效较差,参试浓度防效均在50%以下。初步结论表明,25%咪鲜胺乳油和75%百菌清可湿性粉剂为苗圃防治橡胶树棒孢霉落叶病的较好药剂,推荐使用浓度为2000倍。     

咪鲜胺锰盐是一种很有潜力的油菜菌核病防治药剂

<正>中国农业科学院油料作物研究所一项研究表明,咪鲜胺锰盐是一种很有潜力的油菜菌核病防治药剂。科研人员研究比较了油菜菌核病菌——核盘菌对咪鲜胺锰盐和其余3种杀菌剂的敏感性,以探讨咪鲜胺锰盐防治油菜菌核病的潜力,筛选菌核病防治新药剂。他们先后在实验室测定了不同杀菌剂对核盘菌菌丝生长和菌核萌发的抑     

4种杀菌剂对玉米鞘腐病防效显著

正玉米鞘腐病是玉米上的一种重要鞘部病害,其病原主要为层出镰孢。为筛选该病的有效防治药剂,河北农业大学等单位研究人员合作,选取9种杀菌剂进行了室内毒力测定,并对效果较好的药剂进行了田间防治试验。结果表明:苯醚甲环唑、吡唑醚菌酯、苯甲·嘧菌酯、咪鲜胺、硅唑·咪鲜胺对层出镰孢均有一定的抑制效果,其中苯醚甲环唑、吡唑醚菌酯、咪     

推荐使用咪鲜胺和环酰菌胺交替防治上海地区草莓灰霉病

<正>为阐明上海地区草莓灰霉病病菌对常用杀菌剂的抗药性水平,江苏丘陵地区镇江农科所、上海市农技推广中心研究人员采用区分剂量法,测定了2016年、2017年采集的319株草莓灰霉病病菌(Botrytis cinerea)对9种杀菌剂的抗性,并对菌株的多重抗药性进行了分析。结果表明,所有灰霉病病菌菌     

Location of a high-lysine gene and the DDT-resistance gene on barley chromosome 7

Summary The high-lysine gene in Risø mutant 1508 conditions an increased lysine content in the endosperm via a changed protein composition, a decreased seed size, and several other characters of the seed. The designation lys3a, lys3b, and lys3c, is proposed for the allelic high-lysine genes in three Risø mutants, nos 1508, 18, and 19. Linkage studies with translocations locate the lys3 locus in the centromere region of chromosome 7. A linkage study involving the loci lys3 and ddt (resistance to DDT) together with the marker loci fs (fragile stem), s (short rachilla hairs), and r (smooth awn) show that the order of the five loci on chromosome 7 from the long to the short chromosome arm is r, s, fs, lys3, ddt. The distance from locus r to locus ddt is about 100 centimorgans.     

A note on the origin of Kalanchoë x vadensis Boom & Zeilinga (Crassulaceae)

Summary K x vadensis is a hybrid of K. blossfeldiana and K. marmorata obtained after doubling the number of chromosomes.     

Simultaneous Determination of Four Phenolic Acids in Radix Salviae Miltiorrhizae Formula Granules by QAMS

[Objectives]This study aimed to establish a QAMS(quantitative analysis of multi-components by single-marker)method for simultaneous determination of four phenol...     

Avoidance of leaf rust fungi in wild relatives of cultivated cereals

Summary Avoidance of rust fungi that was based on poor appressorium induction was previously found in Hordeum chilense. In the present study 95 accessions of Triticeae were screened for avoidance of Puccinia hordei. The percentage of appressorium formation per germinated spore ranged from 6 to 90%. On none of the 41 accessions of Aegilops, Agropyron, Elymus, Secale, Thinopyrum or Triticum studied was the rate of appressorium formation lower than 25%. Lower rates of appressorium formation were, however, found on accessions of wild barley species Hordeum brachyantherum, H. marinum, H. parodii and H. secalinum. Its implications in cereal breeding are discussed.     

Present status and future strategy in breeding faba beans (Vicia Faba L.) for resistance to biotic and abiotic stresses

Progress is being made, mainly by ICARDA but also elsewhere, in breeding for resistance to Botrytis, AScochyta, Uromyces, and Orobanche; and some lines have resistance to more than one pathogen. The strategy is to extend multiple resistance but also to seek new and durable forms of resistance. Internationally coordinated programs are needed to maintain the momentum of this work.Tolerance of abiotic stresses leads to types suited to dry or cold environments rather than broad adaptability, but in this cross-pollinated species, the more hybrid vigor expressed by a cultivar, the more it is likely to tolerate various stresses.     

Water Extraction Process of Chinese Herbal Compound Man Gan Ning

[Objectives]To optimize the water extraction process of Chinese Herbal Compound Man Gan Ning and establish a method for its extraction and content determination...     

Cytoplasmic male sterility,resistance to gall mite and mildew,and season of leafing out in black currants

Summary Cytoplasmic male sterility (cms) is described in the F₁ hybrids Ribes × carrierei (R. glutinosum albidum × R. nigrum) and R. sanguineum × R. nigrum. In backcrosses to R. nigrum, progenies with R. glutinosum cytoplasm were either all male sterile, or segregated for full male fertility (F) and complete (S) and partial (I) male sterility. Ratios of F:I+S suggested that two linked genes controlled cms, F plants being dominant for one (Rf ₁) and recessive for the other (Rf ₂).Segregation for cms in relation to three linded genes, Ce (resistance to the gall mite, Cecidophyopsis ribes), Sph ₃(resistance to American gooseberry mildew, Sphaerotheca mors-uvae) and Lf ₁(one of two dominant additive genes controlling early season leafing out) indicated that Rf ₁and Rf ₂were in this linkage group. The gene order and approximate crossover values appeared to be: % MathType!MTEF!2!1!+-% feaafiart1ev1aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn% hiov2DGi1BTfMBaeXafv3ySLgzGmvETj2BSbqef0uAJj3BZ9Mz0bYu% H52CGmvzYLMzaerbd9wDYLwzYbItLDharqqr1ngBPrgifHhDYfgasa% acOqpw0xe9v8qqaqFD0xXdHaVhbbf9v8qqaqFr0xc9pk0xbba9q8Wq% Ffea0-yr0RYxir-Jbba9q8aq0-yq-He9q8qqQ8frFve9Fve9Ff0dme% aabaqaciGacaGaamqadaabaeaafaaakeaacaWGdbGaamyzamaamaaa% baGaaiiiaiaacccacaGGWaGaaiOlaiaacgdacaGG0aGaaiiiaiaacc% caaaGaaiiiaiaacccacaGGGaGaamOuaiaadAgaliaaigdakmaamaaa% baGaaiiiaiaacccacaGGGaGaaiiiaiaaccdacaGGUaGaaiOmaiaacs% dacaGGGaGaaiiiaiaacccacaGGGaGaaiiiaaaacaWGsbGaamOzaSGa% aGOmaOWaaWaaaeaacaGGGaGaaiiiaiaacccacaGGGaGaaiiiaiaacc% cacaGGGaGaaiiiaiaacccaaaGaamitaiaadAgaliaaigdakmaamaaa% baGaaiiiaiaacccacaGGGaGaaiiiaiaacccacaGGGaGaaiiiaiaacc% cacaGGGaGaaiiiaiaacccacaGGGaaaaiaadofacaWGWbGaamiAaSGa% aG4maaaa!6E4D!\[Ce\underline { 0.14 } Rf1\underline { 0.24 } Rf2\underline { } Lf1\underline { } Sph3\]. Crossover values of 0.36 for Ce-Lf ₁, and 0.15 for Lf ₁-Sph ₃were estimated from the relative mean differences in season of leafing out between seedlings dominant and recessive for Ce and Sph ₃.It is suggested that competitive disadvantage of lf ₁-carrying gametes and/or zygotes at low temperatures may be implicated in the almost invariable deficit of plants dominant for the closely linked mildew resistance allele Sph ₃. Poor performance of lf ₁- (and possibly lf ₂-) carrying gametes and young zygotes during periods of low temperature at flowering might also account for the liability of some late season cultivars and selections to premature fruit drop (running off).     

Optimization of Extraction Technology and Determination of Content of Total Phenols of Leaves in Acanthopanax giraldii Harms

[Objectives] To determine the optimum extraction technology for total phenols of leaves in Acanthopanax giraldii Harms.[Methods]The single factor test and ortho...     

Pollen and pollination experiments. III. The viability of apple and pear pollen as affected by irradiation and storage

Summary Apple and pear pollen was irradiated with doses of 0, 50, 100, 250 and 500 krad (gamma rays) and stored at 4°C and 0–10% r.h. From the in-vitro germination percentages an average LD 50 dose of about 220 krad was estimated. For both irradiated and untreated pollen a close and corresponding lineair relationship existed between germination percentage and pollen tube growth.Irradiated pollen was much more sensitive to dry storage conditions than untreated pollen, resulting in less germination and more bursting. Apparently, irradiation caused the pollen cell membrane to lose its flexibility faster than normal. Rehydration of dry-stored, irradiated pollen in water-saturated air restored germination percentages up to their initial levels. The importance of this procedure in germination trials is stressed.     

Screening techniques and sources of resistance to parasitic angiosperms

Parasitic angiosperms cause great losses in many important crops under different climatic conditions and soil types. The most widespread and important parasitic angiosperms belong to the genera Orobanche, Striga, and Cuscuta. The most important economical hosts belong to the Poaceae, Asteraceae, Solanaceae, Cucurbitaceae, and Fabaceae. Although some resistant cultivars have been identified in several crops, great gaps exist in our knowledge of the parasites and the genetic basis of the resistance, as well as the availability of in vitro screening techniques. Screening techniques are based on reactions of the host root or foliage. In vitro or greenhouse screening methods based on the reaction of root and/or foliar tissues are usually superior to field screenings and can be used with many species. To utilize them in plant breeding, it is necessary to demonstrate a strong correlation between in vitro and field data. The correlation should be calculated for every environment in which selection is practiced. Using biochemical analysis as a screening technique has had limited success. The reason seems to be the complex host-parasite interactions which lead to germination, rhizotropism, infection, and growth of the parasite. Germination results from chemicals produced by the host. Resistance is only available in a small group of crops. Resistance has been found in cultivated, primitive and wild forms, depending on the specific host-parasite system. An additional problem is the existence of pathotypes in the parasites. Inheritance of host resistance is usually polygenic and its transfer is slow and tedious. Molecular techniques have yet to be used to locate resistance to parasitic angiosperms. While intensifying the search for genes that control resistance to specific parasitic angiosperms, the best strategy to screen for resistance is to improve the already existing in vitro or greenhouse screening techniques.