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1.
植物表面的毛对螨类的影响及其对害螨生防的启示   总被引:3,自引:1,他引:2  
郑兴国  洪晓月 《昆虫知识》2009,46(2):210-215
植物表面的毛可分为单细胞毛和多细胞毛(一般是腺毛)两大类。它们对植物上的螨类有直接或间接的影响。植物表面毛的作用可分为物理作用和化学作用:物理作用有影响活动、提供附着物(防止从叶面脱落)、提供隐蔽环境(防止捕食者捕食)、改善微环境(主要是维持叶面湿度)或捕捉并维持补充食物量(如花粉、菌类孢子)等形式;化学作用是毛本身所含的或受害螨为害后被诱导产生的化学物质对螨的生长发育和存活产生的影响,或作为有害螨存在的信号对捕食螨发挥作用。关于植物表面的毛对螨类的影响,国内研究得很少。国外的研究多数集中于各种植物上的毛对二斑叶螨Tetranychusurticae等害螨和智利小植绥螨Phytoseiuluspersimilis等捕食性螨的影响。植物表面的毛对螨类的影响很复杂。充分理解各种植物上的毛对螨类的影响可以获得关于害螨生物防治的重要启示。  相似文献   

2.
Meloidoyne incognita (root-knot nematode) and Fusarium solani (root-rot pathogen) were the common soil-borne pathogens and cause severe damage to bean plants in newly reclaimed sandy soil in Nubaryia district, Behera Governorate, Egypt. The antagonistic effects of Trichoderma album and Trichoderma viride as well as three commercial products namely Rhizo-N® (Bacillus subtilis), Bio-Arc® 6% (Bacillus megaterium) and Bio-Zeid® 2.5% (T. album) were tested against M. incognita and F. solani under naturally infected field conditions. T. album and T. viride highly reduced the frequency (%) population of pathogenic fungi such as Fusarium spp., F. solani and Rhizoctonia spp., than the commercial products. Results indicated that all the tested bio-control agents reduced, significantly, the nematode criteria as evidenced by the number of juvenile (J2) in soil and number of galls and egg masses on roots of common bean and Fusarium root-rot incidence (%). Rhizo-N® highly reduced the number of J2 in soil, while T. album was the best in reducing the number of galls and egg masses in roots. The bio-control agents also increased the plant growth parameters of common bean plants i.e. plant height, plant weight, branch no./plant, pods no./plant, pod weight/plant, pod weight, seeds no./plant, fresh seeds weight/pod, dry seeds weight/pod and dry weight of 100 seeds.  相似文献   

3.
金花菌黄色素的稳定性及其抗氧化活性研究   总被引:4,自引:0,他引:4  
李玉婷  吕嘉枥 《微生物学通报》2013,40(11):2030-2036
【目的】评价茯砖茶金花菌黄色素的稳定性和抗氧化性能。【方法】以色素保存率为指标, 研究温度、光照和pH对黄色素稳定性的影响。并对还原能力、DPPH·清除能力和H2O2诱导的红细胞溶血抑制能力进行测定, 考察黄色素的抗氧化性能。【结果】该色素在低温下保存7 d保存率高于98.88%, 温度升高, 保存率降低; 光照尤其是太阳光对其稳定性影响较大; 黄色素在pH 2?10较稳定, pH 12时色素保存率仅为46.22%。低浓度黄色素具有明显高于维生素E (VE)的还原能力、DPPH·清除率和溶血抑制率, 其中DPPH·的EC50低于50 mg/L。【结论】金花菌黄色素对热、酸和弱碱较稳定, 对强碱和太阳光极不稳定, 并有优良的抗氧化能力, 研究和开发前景良好。  相似文献   

4.
分离自黑茶的散囊菌属真菌中的NRPS基因的检测和分布   总被引:1,自引:0,他引:1  
【目的】检测源自黑茶的散囊菌属分离菌株中的NRPS基因,推测它们相应的次级代谢产物合成能力,并考察了基于NRPS基因分布特征进行散囊菌属真菌遗传多样性分析的可能性。【方法】运用IQS法提取来自湖南、四川和湖北等地黑茶样品的14株散囊菌(Eurotium spp.)菌株的总DNA,利用特异性引物对菌株中11种NRPS基因片段进行PCR检测和序列分析,并结合UPGMA法分析了NRPS基因的分布。【结果】各菌株分别含有4 10个NRPS基因片段。NRPS7、CPS1基因在所有菌株中都可以检测到,而NRPS2、NRPS6基因则仅在个别菌株中检测到;其它NRPS基因的分布则呈现出多样性。来自同一块砖茶的菌株Fw-30813-7、Fw-30813-4、Fw-30813-1和Fw-30925-5之间,NRPS1、NRPS2、NRPS3、NRPS4和NRPS8五个基因的分布存在差异,显示出黑茶内散囊菌的遗传多样性。来自湖南白沙溪茶厂的茯砖样品的菌株Fa-20719-3不含有NRPS5和NRPS8基因;而从湖南益阳茶厂茯砖茶7个分离菌株中均含有这两种基因。不同地点加工出来的黑茶样品中的散囊菌菌株之间存在一些明显的遗传差异。【结论】首次从我国黑茶中的散囊菌属分离菌株中检测到NRPS基因,并推测了NRPS产物的多样性,展示了其多样化分布特征,提示NRPS基因的分析有可能成为衡量散囊菌遗传多样性的另一个尺度。  相似文献   

5.
We examined intra- and interspecific predation of adult females and immature stages of the generalist Neoseiulus californicus and the specialist Phytoseiulus persimilis. Adult females and immatures of both predators exhibited higher predation rates on larvae than on eggs and protonymphs. N. californicus fed more inter- than intraspecifically. Predation on P. persimilis by N. californicus was more severe than vice versa. P. persimilis had higher predation rates on conspecifics than heterospecifics and was more prone to cannibalism than N. californicus. When provided with phytoseiid prey, P. persimilis suffered higher mortality than N. californicus. When held without food, adult females and protonymphs of N. californicus survived longer than the corresponding stages of P. persimilis. N. californicus females were able to sustain oviposition when preying upon P. persimilis, whereas cannibalizing females did not lay eggs. Females of P. persimilis were not able to sustain oviposition, irrespective of con- or heterospecific prey. Immatures of both predators were able to reach adulthood when provided with either con- or heterospecifics. Juvenile development of N. californicus was shorter with heterospecific vs. conspecific larvae; mortality of P. persimilis immatures was less when feeding on conspecific vs. heterospecific larvae. Different behavioral pattern in intra- and interspecific predation are discussed in regard to their feeding types (generalist vs. specialist).  相似文献   

6.
Penicillium expansum, Botrytis cinerea and Colletotrichum acutatum are the most common postharvest pathogens of apples, peaches and nectarines. In this study, 96 bacteria were isolated from halophytes rhizosphere and assayed for biocontrol activity under in vitro conditions. Among the 96 isolates tested, isolate S16 effectively inhibited the growth of P. expansum, B. cinerea and C. acutatum. The isolate S16 has reduced 78.33±1.53 to 82.98±2.13% of disease severity in apples, peaches and nectarines. Matrix-assisted laser desorption ionisation-time of flight mass spectrometry of the antifungal compounds revealed three lipopeptide complexes, namely surfactins, iturins and fengycins. Lipopeptides and hydrolytic enzymes produced by the isolate S16 play an important role in the antifungal activity. Polymerase chain reaction analysis using ituD, srfAD, fenD and fenE gene-specific primers showed that the isolate S16 carry sequences similar to ituD, srfAD, fenD and fenE genes. Based on the 16S rDNA sequencing, the effective isolate S16 was identified as Bacillus subtilis.  相似文献   

7.

Background

Xerophilic fungi represent a serious problem due to their ability to grow at low water activities causing the spoiling of low and intermediate moisture foods, stored goods and animal feeds, with the consequent economic losses.

Aims

The combined effect of water activity and temperature of four Eurotium species isolated from animal feeds was investigated.

Methods

Eurotium amstelodami, Eurotium chevalieri, Eurotium repens and Eurotium rubrum were grown at 5, 15, 25, 37 and 45 °C on malt extract agar adjusted with glycerol in the range 0.710–0.993 of water activities.

Results

The cardinal model proposed by Rosso and Robinson (2001) was applied to fit growth data, with the variable water activity at fixed temperatures, obtaining three cardinal water activities (awmin, awmax, awopt) and the specific growth rate at the optimum aw (μopt). A probabilistic model was also applied to define the interface between growth and no-growth. The cardinal model provided an adequate estimation of the optimal aw to grow and the maximum growth rate. The probabilistic model showed a good performance to fit growth/no-growth cases in the predicted range.

Conclusions

The results presented here could be applied to predict Eurotium species growth in animal feeds.  相似文献   

8.
The results of bioassay and colony evaluation demonstrated that British and Texas Buckfast honey bee stocks had one-third to one-half the mean prevalence and abundance of tracheal mites as Canadian standard stock, indicating that Buckfast stocks are less susceptible to tracheal mites than Canadian standard stock. Hybrid Canadian and Buckfast stocks exhibited resistance characteristics similar to only one of their parental stocks, suggesting the colony has an unknown effect on the expression of a bee's resistance to mites. A high correlation (r s=0.66) between abundance values from the bioassay and colony evaluations indicates that the bioassay can be used to screen bees for mite resistance.  相似文献   

9.
Abstract Populations of the morphologically defined taxon Trissolcus basalis (Wollaston) from two major hosts (Nezara viridula [L.] and Agonoscelis rutila [F.]) were tested, using biological criteria, to determine whether they represented populations of one genetical species, or whether they represented populations of two host-associated sibling species. Individuals from both hosts exhibited no obvious courtship differences and they selected mates at random in mate-choice experiments. In addition, female wasps produced offspring of both sexes after mating with a male from either population. We conclude that the individuals of the two populations tested constitute a single genetical species.  相似文献   

10.
The predatory mite Hypoaspis miles was released from laboratory cultures into young crops of pot‐grown cyclamen and poinsettia in six small glasshouses. Five different rates of release were used together with a control house. In both crops, rates of 55 mites per pot and above gave satisfactory control of glasshouse sciarids with no later resurgence of the pest. Mites persisted on the pots until the end of the trial, probably feeding on a residual population of sciarids. In separate tests H. miles was found mostly in the top 1 cm of compost and persisted in horticultural compost for up to 7 weeks in the absence of food.  相似文献   

11.
Discrimination between and predation preference for con- or heterospecific larvae was examined for adult females of P. persimilis and N. californicus in plexiglass cages with and without their primary prey T. urticae. Rates of intra- and interspecific predation on larvae were measured for females held on leaves and provided with excess amounts of spider mites. Females of the generalist N. californicus distinguished con- and heterospecific larvae and preferred to prey upon the latter. Females of the specialist P. persimilis appeared to lack discrimination ability and fed equally on con- and heterospecifics. When spider mites and phytoseiids were offered simultaneously, all P. persimilis females chose to first attack T. urticae, whereas N. californicus females attacked both tetranychids and heterospecific phytoseiids. Females of both predators preyed upon phytoseiid larvae when held on leaves with surplus T. urticae: while P. persimilis fed on both con- and heterospecifics, N. californicus attacked larvae of P. persimilis but avoided cannibalizing larvae. The different behaviors of P. persimilis and N. californicus are discussed with regard to different predation types (generalists vs. specialists) and the possible consequences of mixed release for biological control of spider mites in greenhouses.  相似文献   

12.
13.
The present study is based on oribatid mite material (Acari, Oribatida) collected during the German Expedition in 2011 in Peru. An annotated checklist of identified oribatid mites, including 16 species from 14 genera and 8 families, is provided. Thirteen species and two genera (Notohermannia, Zetomimus) are recorded for the first time in Peru; the genus Notohermannia and species Notohermannia obtusa are recorded for the first time in the Neotropical region. A new species of the genus Pergalumna (Galumnidae), Pergalumna paraboliviana sp. n., is described. The new species is most similar to Pergalumna boliviana Ermilov, 2013 from Bolivia, however, it differs from the latter by the body size, morphology of porose areas A1 and the presence of interlamellar setae.  相似文献   

14.
随着世界经济的发展和全球经济一体化进程的加快,外来物种入侵已成为影响国家安全的主要因素之一。我国外来入侵物种数量繁多,已成为遭受外来生物危害最严重的国家之一,入侵物种已对我国生态系统、环境和社会经济造成了严重的影响。近年来,各国都积极采取措施,制定外来物种入侵管理政策,加强外来物种入侵立法,确保国家及国际生物安全。然而,我国现有的针对外来物种的相关法律法规存在明显滞后。本文综述了我国外来物种入侵的现状及相关立法,指出外来物种入侵可在不同生态系之间发生,揭示了行政区划与生态系差异造成外来物种入侵管理存在"自然与经济的错位"、国内管理方面存在"生态系统与行政区域的错位"的"双错位现象",分析了我国外来物种的管理现状及今后的发展方向,以期探求我国在国际背景下的外来物种管理对策,提出制定《外来入侵物种法》及相关法律的国家体系、建立跨部门协作科学研究体系以及建设行政管理体系,增强抵御外来物种入侵的能力,实施以防为主的管理策略。  相似文献   

15.
New records of torrenticolid water mites (Acari: Hydrachnidia, Torrenticolidae) from Nanshih River, Taiwan, are presented. Two new species are described: Torrenticola nanshihensis and Torrenticola taiwanicus; the latter species is compared with Torrenticola ussuriensis (Sokolow, 1940), a poorly known species which is re-described based on a new material from the Russian Far East; Monatractides cf. circuloides (Halík, 1930)is reported for the first time for Taiwan.  相似文献   

16.
李芳兰  包维楷  庞学勇  冷俐 《生态学报》2009,29(5):2219-2230
为了阐明干旱河谷自然条件下乡土植物种子出苗与幼苗定居能力的空间差异性,选择环境适应能力较强的植被恢复物种,试验选择岷江上游干旱河谷水热条件具有明显差异的两个试验地点:四川省茂县撮箕山(南坡)和两河口(北坡),采用4因素随机区组设计,开展大量的野外播种对比试验,研究了微生境类型改变及不同播种处理方式对白刺花(Sophora davidi (Franch.) Skeels.)、小马鞍羊蹄甲(Bauhinia faberi var. microphylla)、岷谷木蓝(Indigofera lenticallata Craib)、落芒草(Oryzopsis munroi Stapf)和川芒(Miscamthus szechuanesis Keng)5种干旱河谷乡土植物种子出苗、幼苗存活及生长的影响.发现:(1)在干旱河谷自然气候条件下,播种后1个月是所有受试植物出苗的高峰期,但是种子出苗率都很低,达不到30%;幼苗存活能力也极低,在播种1个月后所有幼苗死亡数量增加而保存数明显下降;在播种2个后幼苗存活数均为0.相同条件下小马鞍羊蹄甲、岷谷木蓝与落芒草的出苗数量明显高于白刺花和川芒.这说明干旱河谷地区种子出苗与幼苗存活的限制是自然植被更新能力弱,并且恢复困难的主要原因.(2)种子出苗及幼苗存活能力在不同区域之间具有明显的差异,湿润地段种子出苗数量与幼苗保存数量都较大.但是,种子出苗及幼苗存活能力在同一地段灌丛、半灌丛与裸地等不同类型的微生境之间无明显变化.(3)小容器播种能够有效地增加种子出苗率与短期幼苗存活,但是未能提高幼苗最终的存活能力及生长速率;采用保水剂与腐殖质土壤改良措施对种子出苗数与幼苗保存数没有明显影响,因而这些措施不能解除干旱河谷地区极端环境胁迫对幼苗定居的阻碍.  相似文献   

17.
We report that in Okinawa Island (southern Japan) the pupae of the invasive ant Pheidole megacephala were parasitized by an undescribed Uropodidae mite species. Our observations suggest that by sucking the hemolymph of the ant pupae during its own development, mites induce some conspicuous morphological changes and the death of parasitized P. megacephala pupae. Of the 75 collected nests, 69 (92%) were infested by the mite species. The prevalence of parasitism varied strongly among the worker and sexual castes, with the soldier and male pupae being the most attacked, followed by the minor and queen pupae. Our data represent the first case of such high parasitism in an invasive ant population. Received 2 August 2005; revised 29 September 2005; accepted 7 November 2005.  相似文献   

18.
This study investigated the purification and biochemical characterization of the protease produced by Lactobacillus fermentum R6 isolated from Harbin dry sausages. The optimized fermentation conditions were as follows: a fermentation time of 48 h, an initial pH of 6 and a fermentation temperature of 37 °C. The 37.7 kDa extracellular protease was purified using ammonium sulphate deposition, an ion exchange layer system and gel filtration. The protease produced by L. fermentum R6 had the highest initial velocity and kcat/Km at pH 6, 40 °C. The microbial protease activity could be inhibited by ethylene diamine tetraacetic acid disodium salt (EDTA). The Vmax and Km of the protease were 58.2 ± 1.42 mg/min and 17.3 ± 0.85 mg/mL, respectively. Sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) reflected the ability of the protease to hydrolyse myofibrillar and sarcoplasmic proteins, in particular, myosin heavy chain, paramyosin, phosphorylase and creatine kinase-M type. In conclusion, L. fermentum R6 can be used as a starter culture or an enzyme-producing strain for the inoculation of Harbin dry sausages.  相似文献   

19.
The European grasshopper mite Eutrombidium trigonum (Hermann) lives concealed in the soil in relatively warm and xeric biotopes. The eggs and spermatophores display a moderate drought resistence. The adults, during mating and larvae leave the soil and are to be found on the soil surface. The host range of the parasitic larva is restricted to Saltatoria. The larval growth is much greater than that of other instars of E. trigonum; however, no damage or other effects on the hosts were obvious and usually the hosts survived parasitism. The active post-larval instars of E. trigonum are predatory and feed exclusively on the eggs of Acrididae. The life cycle of E. trigonum is uni- to semi-voltine and is synchronized by an obligatory diapause of the adult instar before reproduction.Deceased.  相似文献   

20.
万方浩 《昆虫知识》2007,44(6):790-797
2002年12月,国家重点基础研究发展计划("973"项目)"农林危险生物入侵机理与控制基础研究"经科技部批准正式立项,2003年启动。文章主要介绍该项目的立项背景、主要研究内容、研究方案和技术路线、总体研究目标及研究进展。  相似文献   

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