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1.
茶橙瘿螨是茶树主要害螨之一,在高山有机茶园主要发生在7~10月份以后,为害夏暑茶和秋茶,严重影响茶叶的品质和产量。试验结果表明,99%绿颖乳油100~250倍对茶橙瘦螨均具有良好的室内毒力效果;在荼橙瘿螨的发生高峰期前喷施100—250倍液,防效良好。  相似文献   

2.
科技简讯     
防治茶树害虫的几种新农药 当前茶叶生产中病虫害仍是一个重要的问题。化学农药在控制病虫为害,确保茶叶一优两高中起着不可低估的作用。80年代以来,新型农药品种不断涌现,品种结构发生了很大的变化,农药使用技术也有较大的提高。为了要使化学农药扬长避短,充分发挥效果,在选用农药品种时,需要了解各种农药的特性和使用技术,才能对症下药,取得预期的效果,现简要介绍几个新农药品种,作为防治茶树害虫的参考。 1.灭螨灵(又名速螨酮,NC—129),是一种杂环类杀螨剂,原药中等毒性,15%制剂属低毒。急性口服LD_(50)为1021~1130mg/kg,急性经皮LD_(50)>2000mg/kg。该药以触杀作用为主,是一种广谱性杀螨剂,兼具杀虫作用。对叶螨、瘿螨、跗线螨等害螨的幼、若、成螨和卵均有良好的防效。它的速效性好,残效期较长,且药效不受温度影响。据中国农业科学院茶叶研究所研究资料,使用15%灭螨灵4000倍防治茶橙瘿螨,喷药后3~14天的防效在86.6%~95.2%,药效在一个月左右。灭螨灵8000~4000倍液对茶跗线螨的防效在80%~100%,并可兼治小绿叶蝉。一年最好控制使用1次,不要和碱性农药混用,不要在蜜蜂采花期使用。安全间隔期暂订7天。  相似文献   

3.
近几年来,我县茶园逐渐蔓延着螨类的危害。在危害茶树的螨类中,据初步调查有茶橙瘿螨、短须螨和茶叶瘿螨三种,其中以叶瘿螨发生量较多,为害面积较大。1984、1985年的7—8月,我们应用美国有利来路化学公司提供的73%的克螨特(Comite)乳剂对茶叶瘿螨进行了田间试验,取得较好的防治效果。现将试验情况小结如下:  相似文献   

4.
《中国茶叶》2008,(6):40-41
以0.3%印楝素乳油700、800、1000倍液,茶联苯2500、2800、3000倍液,万里红2500、3000、3500倍液为供试药剂,对茶小绿叶蝉进行田间药效试验。茶联苯3种浓度药后1天防效分别为99.37%、90.35%、82.31%,药后4天防效分别为97.56%、85.59%、71.87%;03%印楝素乳油3种浓度药后1天防效较差,药后4天防效达高峰,分别为90.81%、80.72%、70.92%;万里红3种浓度药后1天防效分别为87.43%、69.97%、60.62%,药后4天防效显著降低。  相似文献   

5.
为筛选出安全有效地防治高海拔茶区茶饼病的药剂,开展了生物农药氨基寡糖素、申嗪霉素、多抗霉素和矿物油4种药剂及氨基寡糖素与多抗霉素混配剂对贵州湄潭和德江茶园茶饼病的防效试验研究.结果表明:供试生物农药10%多抗霉素处理对贵州湄潭和德江高海拔茶区的茶饼病均有一定的防效(分别为62.43±5.84%和58.17±2.93%);若与5%氨基寡糖素混配后的防效有显著提升(分别为67.3±2.19%和72.77±2.93%),与对照药剂吡唑醚菌酯的防效差异不显著.表明供试生物药剂10%多抗霉素、或10%多抗霉素与5%氨基寡糖素混配使用防治茶饼病可以替代化学农药吡唑醚菌酯,可在我国高海拔茶区大面积应用.  相似文献   

6.
匡海源  林坚贞 《茶叶》2002,28(2):84-85
茶小叶刺瘿螨Phyllocoptacus camelliae Kuang & Lin sp.nov.属于瘿螨科Eriophyidae,叶刺瘿螨亚科Phyllocoptinae,顶背瘿螨族Tegonotini.寄主为茶叶Camellia sinensis,分布在浙江省苍南县和德清县.  相似文献   

7.
果圣防治茶园主要害虫药效试验   总被引:2,自引:0,他引:2  
应用植物源农药0.5%果圣水剂防治茶小绿叶蝉、跗线螨田间试验,结果表明,0.5%果圣对茶小绿叶蝉和跗线螨具有较好的防治效果,并且对茶叶无药害,对茶园蜘蛛等天敌安全。使用0.5%果圣250倍液防治茶小绿叶蝉和跗线螨,药后7d防效分别达到94.63%、91.95%,接近对照药荆10%吡虫啉2000倍液(97.27%)和30%赛丹1000倍液(93.26%)的防治效果,是当前供茶园选择的一种较理想的替代化学农药防治茶小绿叶蝉和跗线螨的药剂。  相似文献   

8.
捕食螨控制茶叶害螨生物防治技术初探   总被引:1,自引:0,他引:1  
在茶园释放两种食虫性螨,用以控制茶叶害螨.结果显示,与对照相比,释放食虫性螨试验区第10天和第30天茶橙瘿螨虫口密度比对照分别低62.81%~93.19%和48.49%~64.52%,其效果优于化学防治区.  相似文献   

9.
阐述了水稻黄化矮缩病在庆安县的发生特点及危害程度。通过改良排灌系统、烧毁病稻草、剔除伤病苗等措施,防效在60%~65%。发病初期,用25%瑞毒霉粉剂800倍液或58%瑞毒锰锌500倍液喷施,防效可达80%;用50%多菌灵800倍液或50%托布津1000倍液喷施防效在70%~80%之间。  相似文献   

10.
三氯杀螨醇的停用及其对策   总被引:6,自引:0,他引:6  
1995年4月,农业部会同化工部、中国茶叶进出口公司、全国植保总站、农业部农药检定所、国家商检总局、北京农业大学、中国农业科学院植保研究所、中国农业科学院茶叶研究所等单位专家在北京专题讨论三氯杀螨醇在茶叶生产中的使用问题并决定停止在茶叶生产上使用三氯杀螨醇.与会专家一致认为,这是一项对我国茶叶生产和出口贸易具有重要意义的决定.三氯杀螨醇是50年代由美国Robm&Haas公司开发的杀螨剂品种,70年代后期起曾在我国茶园中推广应用,因其兼有杀成螨、幼螨、若螨和螨卵的效果,对茶树上的多种害螨,如茶橙瘿螨、茶叶瘿螨、茶短须螨、咖啡小爪螨等均有良好的防效,且残效期长.因此,世界主要产茶国(包括印度、印度尼西亚、日本等国)均将此药作为茶园杀螨剂.尽管三氯杀醇具有良好的杀螨效果,但也有许多缺陷.作者曾在1981年撰文“三氯杀螨醇在茶园中应用问题的讨论”(《中国茶叶》1981年第三期),对该药的应用问题进行讨论,10多年来,这些问题已经更加明确.  相似文献   

11.
12.
Summary

The efficiency of N fertilizers is usually poor; often less than 50% of the applied N is taken up by the crop. This review focuses on various N fertilizers with respect to the significance of different N loss pathways, namely (i) ammonia volatilization, (ii) dinitrogen and nitrogen oxide emissions, and (iii) nitrate leaching. Further, the significance of biological N immobilization, ammonium fixation and, finally, the impact of nitrate vs. ammonium uptake on crop yield are also discussed. The reviewed literature shows that N fertilizers may differ markedly in their susceptibility to losses. There is, however, considerable scope to improve N efficiency of each N source by proper N management practices.  相似文献   

13.
Novel food and non-food uses for sorghum and millets   总被引:4,自引:3,他引:4  
Sorghum and millets have considerable potential in foods and beverages. As they are gluten-free they are suitable for coeliacs. Sorghum is also a potentially important source of nutraceuticals such antioxidant phenolics and cholesterol-lowering waxes. Cakes, cookies, pasta, a parboiled rice-like product and snack foods have been successfully produced from sorghum and, in some cases, millets. Wheat-free sorghum or millet bread remains the main challenge. Additives such as native and pre-gelatinised starches, hydrocolloids, fat, egg and rye pentosans improve bread quality. However, specific volumes are lower than those for wheat bread or gluten-free breads based on pure starches, and in many cases, breads tend to stale faster. Lager and stout beers with sorghum are brewed commercially. Sorghum's high-starch gelatinisation temperature and low beta-amylase activity remain problems with regard to complete substitution of barley malt with sorghum malt . The role of the sorghum endosperm matrix protein and cell wall components in limiting extract is a research focus. Brewing with millets is still at an experimental stage. Sorghum could be important for bioethanol and other bio-industrial products. Bioethanol research has focused on improving the economics of the process through cultivar selection, method development for low-quality grain and pre-processing to recover valuable by-products. Potential by-products such as the kafirin prolamin proteins and the pericarp wax have potential as bioplastic films and coatings for foods, primarily due to their hydrophobicity.  相似文献   

14.
Marine organisms represent an excellent source of innovative compounds that have the potential for the development of new drugs. The pharmacokinetics of marine drugs has attracted increasing interest in recent decades due to its effective and potential contribution to the selection of rational dosage recommendations and the optimal use of the therapeutic arsenal. In general, pharmacokinetics studies how drugs change after administration via the processes of absorption, distribution, metabolism, and excretion (ADME). This review provides a summary of the pharmacokinetics studies of marine-derived active compounds, with a particular focus on their ADME. The pharmacokinetics of compounds derived from algae, crustaceans, sea cucumber, fungus, sea urchins, sponges, mollusks, tunicate, and bryozoan is discussed, and the pharmacokinetics data in human experiments are analyzed. In-depth characterization using pharmacokinetics is useful for obtaining information for understanding the molecular basis of pharmacological activity, for correct doses and treatment schemes selection, and for more effective drug application. Thus, an increase in pharmacokinetic research on marine-derived compounds is expected in the near future.  相似文献   

15.
Résumé Fusarium culmorum et, dans une moindre mesure,F. avenaceum, F. sambucinum, Colletotrichum coccodes etCylindrocarpon sp. ont été isolés de tubercules entreposés en atmosphère contr?lée (AC) et atteints de pourriture grave. Des expériences d'inoculation de tubercules avec 10 espèces ou variétés fongiques et conservation en AC à 8 et 10°C ont montré que: 1) les champignons non pathogènes en atmosphère normale (ex.:Cylindrocarpon sp.) le devenaient en AC, 2) ceux qui étaient faiblement pathogènes en atmosphère normale étaient nettement plus virulents en AC (ex.:F. culmorum), 3) les espèces ou variétés virulentes en conditions d'air normales (Fusarium sulphureum etPhoma exigua var.foveata) ne provoquaient pas de pourriture plus grave en AC et leur activité pouvait même être légérement freinée.
Summary The extensive rotting of tubers which occurred during storage trials in controlled atmospheres has led to a mycological and pathological study of the rots. The most frequently isolated species wasFusarium culmorum althoughF. avenaceum, F. Sambucinum, Coletotrichum coccodes and aCylindrocarpon sp. were also present. Tubers of cvs Bintje and Ulla were inoculated with 19 isolates of 10 fungal species or varieties associated with rotting of stored tubers (Table 1). The tubers were incubated at 8 or 10°C in normal or controlled (2% O2:1% CO2, 2% O2:6% CO2, 2% O2:12% CO2, 6% O2:6% CO2) atmospheres and the extent of rotting was determined a month later (Tables 2 and 3 and Fig. 2). Species which were weakly virulent in a normal atmosphere (variousFusarium spp. andPhoma exigua var.exigua) were clearly more aggressive in the controlled atmosphere and this was especially evident in the case ofF. culmorum. Species ot pathogenic in a normal atmosphere under experimental conditions (Colletotrichum coccodes, Cylindrocarpon sp.,Phoma eupyrena) caused rotting in the controlled atmosphere. The two species which were virulent in a normal atmosphere (F. sulphureum andP. exigua var.foveata) were also virulent in the controlled atmosphere and in some cases the extent of rotting was even less. As a general rule, rotting caused by weakly virulent fungi was greater in both cultivars in the controlled than in a normal atmosphere.

Zusammenfassung Eine starke F?ulnis von in Kontrotrollierter Atmosph?re gelagerten Kartoffelknollen veranlasste eine mykologische und pathologische Untersuchung. Der am h?ufigsten isolierte Pilz warFusarium culmorum. F. avenaceum, F. sambucinum, Colletotrichum coccodes undCylindrocarpon sp. wurden ebenfalls bestimmt. Neunzehn St?mme von 10 Pilzsorten oder-Arten welche bei Lagerf?ulnis vorkommen (Tab. 1) wurden auf Knollen der Sorten Bintje und Ulla inokuliert. Die Lagerung wurde bei 8 oder 10°C under Normalbedingungen oder kontrollierter Atmosph?re durchgeführt (2% O2:1% CO2, 2% O2:6% CO2, 2% O2:12% CO2, 6% O2:6% CO2). Der F?ulnisgrad (Abb. 1) wurde nach einem Monat bonitiert. Die Ergebnisse sind in den Tabellen 2 und 3 dargestellt und in der Abb. 2 illustriert. Unter in Normalbedingungen nur schwach virulente Arten (verschiedeneFusarien undPhoma exigua var. exigua) waren deutlich aktiver in kontrollierter Atmosph?re. Dies was besonders der Fall fürF. culmorum. Pilze, die im Versuch unter Normalbedingungen nicht pathogen waren (Colletotrichum coccodes, Cylindrocarpon sp., Phoma eupyrena), haben unter kontrollierter Atmosph?re Sch?den verursacht. Hingegen werden die beiden unter Normalbedingungen sehr pathogenen Arten (F. sulphureum undP., exigua var.foveata), durch kontrollierte Atmosph?re wenig beeinflusst. Es wurde sogar in einigen F?llen eine gewisse Verringerung des F?ulnisbefalls beobachtet. Ganz allgemein haben die getesteten kontrollierten Bedingungen die Entwicklung der Pilzf?ulnis an beiden Kartoffelsorten gef?rdert, speziell durch Pilzarten, welche unter Normal-bedingungen wenig Sch?den verursachen.
  相似文献   

16.
Flavonoids-enriched tissues of citrus such as peel, immature fruit and flower are consumed as culinary seasonings, tea ingredients in China for centuries. This HPLC quantitative study on the five citrus flavonoids, naringin, hesperidin, neohesperidin, sinensetin and nobiletin on a wide range of Chinese citrus fruits and several Traditional Chinese Medicinal food ingredients in East China, revealed a great diversity in flavonoid composition. Huyou peel (C. paradisi cv. Changshanhuyou) was found to be the best naringin (3.25%) and neohesperidin (2.76%) source; C. aurantium, a major ingredient of several citrus-related TCM, is also a suitable source of naringin and neohesperidin, and a good juice source for flavanone glycosides; the peel of Wenzhoumiju (C. unshiu) is one of the richest local species in hesperidin (up to 6.25%); Zaoju (C. subcompressa) has the highest content of nobiletin (0.59%), a polymethoxylated flavone. LC-ES-MS analysis of Zanthoxylum genus for flavonoids revealed for the first time the presence of significant amounts (0.74%) of hesperidin in the root of Liangmianzhen (Z. nitidum (Roxb.) DC), a relative of Sichuan pepper, which is a spice widely used in China.  相似文献   

17.
Evolutionary aspects of the trade-off between seed size and number in crops   总被引:1,自引:0,他引:1  
Victor O. Sadras   《Field Crops Research》2007,100(2-3):125-138
Whereas the concept that availability of resources drives seed production is sound in principle, it is incomplete as there are many solutions to the allocation of resources that derive from the trade-off between number and size. This paper examines evolutionary aspects of this trade-off in annual grain crops. The analysis is centred on the working hypotheses that, for a given species and environment, allocation of resources to reproduction involves (H1) high plasticity in seed number, which allows for variable resource availability, and (H2) a relatively narrow range of seed size that results from evolutionary and agronomic selection. Comparisons between crops and fish are used to highlight common evolutionary elements in taxa where parents provide little or no care to their offspring, with the consequence that both number and early survival of offspring, hence fitness of parents, are partially related to embryo size and reserves.

The plasticity of seed number in relation to availability of resources is analysed against the established relationship between offspring number and parent growth rate during critical stages. The notion that seed size is under stabilising selection is analysed against three conditions: (1) mean seed size is conservative for a given species and environment, (2) seed size affects fitness, and (3) seed size is heritable. Databases from published papers were compiled to analyse the relative variability of seed size and number, and the heritability of seed size. Evidence for and against the link between seed size and parental fitness is revised using the Smith–Fretwell model as framework (Am. Nat., 108, 499–506).

The proposal of high plasticity of seed number and narrow variability of seed size resulting from stabilising natural selection is generally consistent with evolutionary and genetic considerations. Agronomic selection may have reinforced natural selection leading to relatively narrow seed size in species such as wheat and soybean, where cultivated types retained high plasticity for seed number. In contrast, selection for one or few inflorescences in crops like sunflower and maize may have morphologically reduced seed number plasticity and increased variability of seed size and its responsiveness to resource availability in relation to their wild ancestors.  相似文献   


18.
The review of the 2016–2017 marine pharmacology literature was prepared in a manner similar as the 10 prior reviews of this series. Preclinical marine pharmacology research during 2016–2017 assessed 313 marine compounds with novel pharmacology reported by a growing number of investigators from 54 countries. The peer-reviewed literature reported antibacterial, antifungal, antiprotozoal, antituberculosis, and antiviral activities for 123 marine natural products, 111 marine compounds with antidiabetic and anti-inflammatory activities as well as affecting the immune and nervous system, while in contrast 79 marine compounds displayed miscellaneous mechanisms of action which upon further investigation may contribute to several pharmacological classes. Therefore, in 2016–2017, the preclinical marine natural product pharmacology pipeline generated both novel pharmacology as well as potentially new lead compounds for the growing clinical marine pharmaceutical pipeline, and thus sustained with its contributions the global research for novel and effective therapeutic strategies for multiple disease categories.  相似文献   

19.
SUMMARY

Vitamin A, iodine, and iron deficiencies affect large numbers of people worldwide. A deficiency of one or more of these micronutrients adversely affects the physical and mental abilities of humans. South Asia contains a high percentage of these individuals, not just because of its large population, but also the prevalence of deficiency is higher there than in many other parts of the world. The reasons for the high rates of deficiency in South Asia are many, but they include inadequate availability of micronutrient-rich foods, sub-optimal dietary habits, and high rates of infection. Across the region, national plans vary from (a) increasing availability of appropriate foods, (b) introducing new dietary behaviors, (c) improving health status, and (d) directly addressing deficiency through intervention programs. The extent to which each of the countries is making progress toward the goals of these plans can help in understanding the priorities for future efforts to address micronutrient malnutrition. This article discusses the adverse effects of micronutrient deficiencies in humans with special reference to South Asia.  相似文献   

20.
Summary The viability of five pathogens was decreased by treatment with hot water when tested in vitro.Polyscytalum pustulans was most sensitive andRhizoctonia solani least sensitive. Potato tubers were exposed to 55°C for 5 min in a commercial continuous hot water treatment plant using naturally contaminated seed tubers and tubers which had been inoculated by dipping in comminuted cultures. The frequency of eyes colonised byP. pustulans, Helminthosporium solani, andR. solani was reduced to virtually zero and the effect persisted on tubers subsequently stored at 4°C and at 15°C for up to 16 wk. Results withColletotrichum coccodes were inconclusive. Treatment suppressedPenicillium spp. which, however, rapidly recolonised the eyes during storage, leading to higher contamination levels in the treated than in the untreated tubers. With tubers inoculated withPhoma foveata, good control was achieved when the incubation period before treatment was 10 d but not when the period was 42 d.  相似文献   

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