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1.
为了解桃小食心虫(Carposina sasakii Matsumura)在新寄主植物黑李上的发生情况,以闽东黑李种植示范基地核心区为观测和试验点,调查该虫的为害过程及发生规律,评价4种地面喷施药剂及4种果面喷施药剂的田间药效,筛选最佳防控药剂。结果表明:桃小食心虫只为害果实,4月下旬,成虫将卵散产于多地,初孵幼虫当天入蛀果内,果内虫道弯曲且充满虫粪,到6月上旬,老熟幼虫外啃脱果孔,入土结茧。诱捕成虫数量和果实表面着卵量随时间均呈“M”型变动,都可划分为初始上升期、相对平稳期和持续回落期,但它们起始、第1峰值、第2峰值及终结的时间节点不同,成虫羽化历期约33 d,成虫产卵果实表面历期约28 d。4种地面喷施药剂对老熟幼虫破冬茧出土的高抑制作用很难持续,48%毒死蜱乳油或52.25%氯氰·毒死蜱乳油前期抑制效果较好,1%甲氨基阿维菌素乳油的相对持效抑制作用较好。4种果面喷施药剂,如药前卵果或虫果基数较低,应使用持效性较好的1%甲氨基阿维菌素乳油,如药前卵果或虫果基数较高,就应使用35%氯虫苯甲酰胺水分散粒剂。  相似文献   

2.
腰果蛀果斑螟的发生与防治   总被引:2,自引:1,他引:2  
在海南岛南部,腰果蛀果斑螟(Nephoptefyx sp.)一年发生9代。田间始见期为10—11月,末见期为7月中下旬。4—6月是该虫大发生为害期,田间虫果率为20~60%。 4—7月间完成一代所需时间雄虫为26~31天,雌虫28~36天;10—3月份完成一代雄虫需28~34天,雌虫30~36天。成虫产卵对果实的部位以及果实的发育阶段有明显的选择性。幼虫具转果为害的习性。蛹在树冠下土壤中呈不均匀水平分布。种群虫口的建立与田间结果量的增长同步,产量损失因果实发育阶段而异。田间中果态果实坚果受害最重,是重点保护目标。防治措施,目前以化学防治为主,有效药剂有敌杀死、速灭杀丁、杀虫双和乐果等,第一次喷药防治适期应在田间大量果实即将进入中果态之时,在乐东腰果植区通常为8月中下旬。第一次喷药后,连续用药2~3次,即可保护95%以上的果实免遭虫害。此外,结果早期摘除树上虫蛀果,收集地上落果及利用害虫潜伏场所进行毒杀,对降低害虫种群虫口有重要意义。  相似文献   

3.
人心果花果的生物学特性及其栽培技术   总被引:1,自引:0,他引:1  
人心果(Achras zapota L.)是山榄科热带名果,它的树胶是制口香糖的原料.福建是我国最早引进人心果的省份,早在清·光绪26年(公元1900年),归侨陈仙精从新加坡携带人心果苗回国种于厦门禾山殿前,至今虽有80多年的历史,但对它的生物学特性却很少研究.人心果的花果生物学特性和我国原产的荔枝、龙眼等果树的生物学特性很不相同,故不能用栽培荔枝、龙眼的技术指导种植人心果.为了探讨和了解人心果的花果生物学特性,从而提出相适应的栽培技术措施,笔者从1958年起在厦门开始对人心果这一外来名果曾进行了观察、调查、试验与研究.现将人心果花果的生物学特性的几个主要问题,  相似文献   

4.
通过1979—1982年室内试验和田间调查结果表明,6月上、中旬当气温达20℃以上时,成虫出现高峰,进入发生盛期.此时要做好成虫预报工作,及时进行防治.在成虫发生期,平均每百米垅长数量超过10头(雌雄比例近1:1).第二年局部地块将遭幼虫严重为害,每百米垅长不足10头成虫,第二年局部地块会受中度或轻度为害,而百米垅长只有2—3头成虫时,大部份地块不受害.幼虫的越冬密度大小,是第二年防治指标.一般成虫发生量大,幼虫越冬密度也大.7月份总降雨量达150—200毫米时,成虫发生量大幼虫越冬密度也大.但此时总降雨量在60—80毫米时,尽管成虫发生量多,幼虫越冬密度反而减少.豆茬或隔年豆茬幼虫越冬密度大,如种甜莱,当测得每平方米有0.5—1头幼虫时,必进行防治。成虫的防治,以辛硫磷乳剂800倍液,防效达90%以上。幼虫防治,以3%呋喃丹或3%甲基异柳磷颗粒剂,亩用1.5—2公斤,随种入土,当每平方米有蛴螬1—4头时,保苗率达78%以上。如超过5头,适当增加用量.  相似文献   

5.
人心果斑螟生物学特性及防治的研究   总被引:1,自引:0,他引:1  
用变温法则测定室内自然变温条件下饲养的人心果斑螟(Nephopteryx sp.)各虫态发育起点温度及世代发育有效积温,结果是发育起点温度为卵13.23℃,幼虫17.71℃,蛹9.66℃,成虫6.11℃,全世代平均11.68℃,完成一世代的有效积温为408.4日度。用1/100毫米读数显微测微尺逐个测定幼虫头宽值,通过众数原理计算,幼虫有5个龄期,各龄期头宽值(毫米)分别为1龄0.316,2龄0.708,3龄1.126,4龄1.401,5龄1.668。通过室内化学毒力测定,杀卵和幼虫的有效农药有80%敌敌畏乳剂、50%甲胺磷乳剂等。  相似文献   

6.
分别用番茄果实、辣椒果实和人工饲料饲养斜纹夜蛾,观察不同食料对斜纹夜蛾(Spodoptera litura Fabricius)的生长发育、存活、不同龄期幼虫的粪便重量、成虫产卵量的影响,组建相应食料下的斜纹夜蛾实验种群生命表.结果表明:喂饲辣椒果实的斜纹夜蛾幼虫发育历期和全世代显著长于喂饲番茄和人工饲料,喂饲人工饲料的斜纹夜蛾不同龄期幼虫的粪便重量显著重于喂饲辣椒果实;种群趋势指数(Ⅰ)均大于1, 内禀增长力(rm)均大于0,斜纹夜蛾种群呈增长趋势.  相似文献   

7.
本研究通过对人工饲料加豆蚜及纯豆蚜饲养的七星瓢虫对茶蚜的捕食能力进行评价,以倒数法拟合Holling圆盘方程,明确不同饲养方式七星瓢虫对茶蚜的捕食能力.研究结果表明,当N→∞时,每头豆蚜饲养的七星瓢虫成虫的后代1~4龄幼虫以及雄雌成虫在1 d内对茶蚜的最大捕食量分别为30.7692、94.3396、303.0303、588.2353、222.2222、500.0000头.当N→∞时,每头混合饲养的七星瓢虫成虫的后代1~4龄幼虫以及雄雌成虫在1d内对茶蚜的最大捕食量分别为29.6736、112.3596、277.7778、555.5556、120.4819、188.6793头.豆蚜饲养七星瓢虫和混合饲养七星瓢虫成虫两种方式饲养的七星瓢虫第1代各龄幼虫对茶蚜的捕食量之间没有显著性差异(P>0.05,n=6),混合饲养七星瓢虫幼虫羽化的成虫对茶蚜的捕食量极显著低于豆蚜饲养七星瓢虫幼虫羽化的成虫对茶蚜的捕食量(P<0.01,n=6).本研究表明,混合饲养的七星瓢虫对茶蚜具有较强的捕食能力,在七星瓢虫对茶蚜的防治应用中具有广泛前景.  相似文献   

8.
腰果云翅斑螟的初步研究   总被引:3,自引:1,他引:2  
腰果云翅斑螟(Nephop teryx sp.)是我国腰果的新害虫,其幼虫蛀食坚果及果梨,据1985年调查最高为害率达60.2%。幼嫩坚果被蛀食后,种仁无法形成,最后导致干枯;较老的坚果被蛀食后,种仁扭曲,降低商品价值;果梨被蛀食后,引起腐烂。腰果云翅斑螟一代需时30~34天。此虫的发生与腰果结果期相吻合。成虫白天躲于枝条上,其活动盛期在傍晚及清晨;一头雌成虫最高产卵量125粒,卵产于果腹、果蒂、果柄及花萼萼片处;幼虫5龄;化蛹场所主要在植株冠幅下离土表约1厘米深的土中。建议喷射敌敌畏或杀螟松并结合摘除带虫果及收集落地被害果,挖掘蛹等综合措施对此虫进行防治。  相似文献   

9.
对腰果云翅斑螟(Nephopteryx sp.)幼虫发生动态及空间分布型进行研究.结果表明,腰果果实被害率和果虫量的发生动态曲线均为双峰型,其高峰期均分别出现在中果期和末果期.株虫量的发生动态曲线为单峰型,其高峰期出现在盛果期.不同结果期对腰果云翅斑螟幼虫以及被害果实在腰果植株上的空间分布均无影响,均呈聚集分布.不同结...  相似文献   

10.
不完全二代区玉米螟种群动态的生态过程与发生量预测   总被引:4,自引:0,他引:4  
玉米螟(Ostrinia furnacalis)是我国东北玉米生产的主要害虫,近年来危害加重。本文概述了在不完全二代区,玉米螟发生量预测的必要性及国内外研究现状,对不完全二代区的亚洲玉米螟(ACB)种群动态的生态过程做了详细的论述。以ACB种群的系统分析为基础,从越冬幼虫的滞育率、冬季死亡率、冬后化蛹、羽化率、至成虫死亡率、成虫迁入产卵对寄主的选择性及成虫的产卵量,最后到田间卵、蛀前幼虫、蛀后幼虫的死亡率及其影响因子天气、天敌、寄主等均做了论述。本文最后讨论了越冬源基数,成虫数量及田间卵量和造成危害的4~5龄幼虫间的相互关系及其在预测中的作用。  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.
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   

17.
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   

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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