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1.
为了研究香蕉根颈象甲在海南香蕉上的产卵特性,指导田间防控技术,室内研究了香蕉根颈象甲成虫对寄主植物、叶鞘部位的产卵选择性及不同饲养方式下的产卵率。结果表明,在巴西蕉和泰国蕉上,香蕉根颈象甲的产卵率分别为32.87%和30.93%,均显著高于台蕉、大蕉、皇帝蕉和粉蕉;香蕉根颈甲成虫嗜好在香蕉假茎中部叶鞘产卵,在第2层叶鞘的选择性最高,选择系数为45.78%,显著高于其它几层叶鞘的选择系数;分别提供腐烂和新鲜的香蕉假茎让香蕉根颈象甲产卵,周平均产卵量分别为4粒和2粒,可见,香蕉根颈象甲喜欢在腐烂的假茎上产卵。  相似文献   

2.
香蕉根颈象甲[Cosmopolites sordidus(Gemar)1已在海南香蕉园发生,对香蕉生产造成危害.为了研究香蕉象甲的分布和发生规律、指导田间取样,应用几种聚集度指标的计算公式以及Taylor幂法则、Iwao的m*-m回归分析法,分析和测定了香蕉根颈象甲卵的空间分布格局和田间理论抽样数.结果表明:海南香蕉根颈象甲卵在一定密度下呈聚集分布,空间分布符合负二项分布;聚集度指标,I>0,m*/m>1,C>1,Cα>0;Tavlor幂模型表明香蕉根茎象甲卵在一定密度下的分布为聚集的,而且聚集强度随种群密度的上升而升高:Iwao的m*-m回归模型分析表明,m*和m呈显著相关,香蕉根茎象甲个体间相互吸引,最适抽样数n与卵密度m及相对误差D的关系为:n=1/D2(1.3717/m+0.046 3).  相似文献   

3.
李嘉 《热带作物学报》2012,32(11):77-81
香蕉象甲(Cosmopolites sordidus)是最具破坏力的香蕉(Musa spp.)害虫。信息化合物对香蕉象甲生物学特征的调节起到了非常重要的作用,并且已被应用于其防治。这些信息化合物包括寄主植物挥发物和信息素。本文对香蕉象甲信息化合物及其应用研究的主要成果进行了综述,以此作为进一步研究的参考。这方面研究的拓展和深入将推动新的环保高效的香蕉象甲防治手段的发展及完善。  相似文献   

4.
香蕉象甲(Cosmopolites sordidus)是芭蕉属(Musa spp.)经济作物最具破坏力的害虫,如何对其进行有效防治已成为一项重要议题。球孢白僵菌(Beauveria bassiana)在香蕉象甲防治方面具有很好的应用效果,对其应用研究的主要成果进行概述,这对以后进一步研究球孢白僵菌等昆虫病原真菌及其在害虫防治上的应用具有重要的参考价值。  相似文献   

5.
香蕉假茎象甲成虫的空间格局研究   总被引:1,自引:1,他引:0  
香蕉假茎象甲成虫的空间分布规律研究结果表明,香蕉假茎象甲成虫在香蕉园呈较强的聚集分布,平均拥挤度、个体群平均大小随成虫密度增大而增大,个体群所占空间随密度增大而减小;成虫聚集分布主要是由于蕉园环境的异质性引起的。建立了成虫最适理论抽样数公式,提出了为防治决策服务的序贯抽样模型。   相似文献   

6.
应用苹果蠹蛾线虫防治香蕉扁黑象甲的研究   总被引:9,自引:1,他引:9  
1988—1990年,淋或喷施苹果巍蛾线虫(Steinernema carpocapsae)3~6×10~6条/株水悬浮液至越冬留头蕉茎上,防治香蕉扁黑象甲越冬幼虫并兼治蛹和成虫,取得了较好的效果,幼虫、蛹、成虫的死亡率分別为73%~90%,68%~92%,25%~80%,为香蕉扁黑象甲的防治开辟了新的、有效的途径。  相似文献   

7.
红棕象甲幼虫化学防治研究   总被引:4,自引:0,他引:4  
针对红棕象甲的生物学特性,采用灌根法、灌淋法、打孔注药法和熏蒸法等化学防治方法对红棕象甲幼虫进行了野外防治试验.结果表明,防治效果依次为:熏蒸法>打孔注药法>灌淋法>灌根法.用磷化钙以每株树9.6g的剂量进行根部熏蒸,5d后防效达83.03%,可在生产中推广应用.  相似文献   

8.
应用日立S-3000N型扫描电镜对香蕉假茎象甲雌、雄成虫的触角形态和感器进行了观察。结果表明:香蕉假茎象甲触角为膝状,由柄节、梗节和鞭节组成。触角表皮普遍具有波浪形刻纹,共有4种感器,即毛形感器、刺形感器、锥形感器和芽孢形感器,其中,毛形感器有3种类型,刺形感器有2种类型。香蕉假茎象甲雌、雄个体间触角感器类型及其分布均无明显差异。触角上的各种感器类型多样,数量众多,分布集中,鞭节上感器最多,梗节次之,柄节无感器。  相似文献   

9.
香蕉枯萎病己成为香蕉的毁灭性病害。该病属于土传性病害,扩散蔓延速度快,难于进行生物控制、药物防治及轮作、浸田等常用防治方法的防治。因此,防治香蕉枯萎病的最佳方法是进行香蕉遗传改良,培育抗病品种。选用从INIBAP[(International Network for the Improvement of Bnana and Plantain,国际香(大)蕉改良网络)]引进的42份香蕉种质资源,采用伤根侵染法,用含2×106个孢子/L的香蕉枯萎病1号和4号小种菌液分别对42份香蕉幼苗进行处理,筛选抗香蕉枯萎病种质。结果表明:在侵染1号小种时,7份材料表现高感,13份感病,22份中抗,无高抗;在侵染4号小种时,25份材料表现高感,12份感病,5份中抗,无高抗。综合分析显示,M11和M25对枯萎病1号和4号小种均表现中抗。  相似文献   

10.
对稻水象甲防治药剂的防治效果进行研究,田间试验结果表明,48%乐斯本乳油防治稻水象甲成虫有较好的效果。每667m2施用48%乐斯本乳油75ml防效达90.6%,持效期7d以上。  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.
Summary The effects of the leaves of five plant species, one from each of the generaAmbrosia, Anemone, Eupatorium, Eucalyptus andLantana, on potato tuber moth were investigated under indigenous storage conditions at the Central Potato Research Station, Shillong (1800 m above sea level). Their action was compared with that of a biological insecticide (spores ofBacillus thuringiensis), a chemical insecticide (carbaryl), and an untreated control. The data collected after six months storage on tuber damage, sprout damage and the rotting indicated that the leaves ofLantana aculeata provided most protection to the tubers, reducing damage from over 70% in the check to below 5%, and sprout damage from over 45% to below 3%. Next best wasEucalyptus globulus followed byB. thuringiensis. They may be used on tubers stored for table use or for seed as they had no adverse effect on germination or on the yield of a subsequent crop.  相似文献   

14.
15.
Teas of plant origin traditionally consumed by the Mountain Pima of Chihuahua, Mexico, were analyzed for mineral nutritional content. Fe, Cu, Zn, Ca, and Mg composition was determined for native teas made from shoots ofTagetes lucida, T. filifolia, Elytraria imbricata, andHolodiscus dumosus, and from root xylem ofCeanothus depressus andPhaseolus ritensis. Native uses of these teas are also described.  相似文献   

16.
Summary The in vitro antimicrobial activity of extracts from accessions ofSolanum commersonii Dun. collected in the south of Uruguay was investigated against five microorganisms including the pathogenRalstonia solanacearum. A total of 30 extracts corresponding to organic and aqueous extracts were studied. Interestingly, most of the positive results for growth inhibition were againstR. solanacearum. The extracts were also analyzed for the presence of glycoalkaloids and lectins. Six of the ten aqueous extracts showed lectin presence and a wide variation in the type and amounts of glycoalkaloids, was found. Results indicate that there is no clear relationship between the antimicrobial activity against the five microorganisms screened and the presence or amounts of lectins and glycoalkaloids, traditionally regarded as possible antimicrobial metabolites in theSolanum genus, which indicates the presence of as yet unidentified antimicrobial compounds.  相似文献   

17.
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   

18.
Summary Clones derived from thirty-one different accessions (nineteen of Argentine origin) belonging to eightSolanum species were screened for resistance to infection by potato virus X strain cp (PVX cp) by mechanical inoculation of plantlets that had been micropropagated in vitro. Estimates of PVX multiplication obtained by enzyme linked immunosorbent assay and slot blot nucleic acid hybridization allowed the identification of resistant clones derived from five accessions belonging toS. commersonii S. oplocense, S. sparsipilum andS. tuberosum andigena. Resistant genotypes supported PVX concentrations 5 to 15 times smaller than did the susceptible control cultivar Spunta. Graft inoculation test confirmed the presence of extreme resistance similar to that conferred by the ‘immunity’ gene X1 (also called RXact).  相似文献   

19.
The loss of density and elasticity, the appearance of wrinkles and hyperpigmentation are among the first noticeable signs of skin aging. Beyond UV radiation and oxidative stress, matrix metalloproteinases (MMPs) assume a preponderant role in the process, since their deregulation results in the degradation of most extracellular matrix components. In this survey, four cyanobacteria strains were explored for their capacity to produce secondary metabolites with biotechnological potential for use in anti-aging formulations. Leptolyngbya boryana LEGE 15486 and Cephalothrix lacustris LEGE 15493 from freshwater ecosystems, and Leptolyngbya cf. ectocarpi LEGE 11479 and Nodosilinea nodulosa LEGE 06104 from marine habitats were sequentially extracted with acetone and water, and extracts were analyzed for their toxicity in cell lines with key roles in the skin context (HaCAT, 3T3L1, and hCMEC). The non-toxic extracts were chemically characterized in terms of proteins, carotenoids, phenols, and chlorophyll a, and their anti-aging potential was explored through their ability to scavenge the physiological free radical superoxide anion radical (O2•−), to reduce the activity of the MMPs elastase and hyaluronidase, to inhibit tyrosinase and thus avoid melanin production, and to block UV-B radiation (sun protection factor, SPF). Leptolyngbya species stood out for anti-aging purposes: L. boryana LEGE 15486 presented a remarkable SPF of 19 (at 200 µg/mL), being among the best species regarding O2•− scavenging, (IC50 = 99.50 µg/mL) and also being able to inhibit tyrosinase (IC25 = 784 µg/mL), proving to be promising against UV-induced skin-aging; L. ectocarpi LEGE 11479 was more efficient in inhibiting MMPs (hyaluronidase, IC50 = 863 µg/mL; elastase, IC50 = 391 µg/mL), thus being the choice to retard dermal density loss. Principal component analysis (PCA) of the data allowed the grouping of extracts into three groups, according to their chemical composition; the correlation of carotenoids and chlorophyll a with MMPs activity (p < 0.01), O2•− scavenging with phenolic compounds (p < 0.01), and phycocyanin and allophycocyanin with SPF, pointing to these compounds in particular as responsible for UV-B blockage. This original survey explores, for the first time, the biotechnological potential of these cyanobacteria strains in the field of skin aging, demonstrating the promising, innovative, and multifactorial nature of these microorganisms.  相似文献   

20.
The peer-reviewed marine pharmacology literature from 2009 to 2011 is presented in this review, following the format used in the 1998–2008 reviews of this series. The pharmacology of structurally-characterized compounds isolated from marine animals, algae, fungi and bacteria is discussed in a comprehensive manner. Antibacterial, antifungal, antiprotozoal, antituberculosis, and antiviral pharmacological activities were reported for 102 marine natural products. Additionally, 60 marine compounds were observed to affect the immune and nervous system as well as possess antidiabetic and anti-inflammatory effects. Finally, 68 marine metabolites were shown to interact with a variety of receptors and molecular targets, and thus will probably contribute to multiple pharmacological classes upon further mechanism of action studies. Marine pharmacology during 2009–2011 remained a global enterprise, with researchers from 35 countries, and the United States, contributing to the preclinical pharmacology of 262 marine compounds which are part of the preclinical pharmaceutical pipeline. Continued pharmacological research with marine natural products will contribute to enhance the marine pharmaceutical clinical pipeline, which in 2013 consisted of 17 marine natural products, analogs or derivatives targeting a limited number of disease categories.  相似文献   

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