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李树桑白蚧是福州市永泰县李树上的重要害虫之一。通过对2007—2008年李树桑白蚧发生规律调查和田间药效试验,基本掌握了永泰县李树桑白蚧的发生规律：第一代卵孵化高峰期为3月下旬末至4月上旬;第二代为5月下旬中期至6月上旬中期;第三代为7月下旬初至8月上旬初,第四代9月下旬初至10月上旬初。田间防治要在（2月下旬至3月上旬）越冬2龄若虫脱出蜡堆和卵孵化高峰期,用40%速扑杀EC1 200倍液,或48%乐斯本EC1 200倍液,或25%吡蚜酮WP2 000倍液加25%噻嗪酮WP1 500倍液喷雾防治,间隔7d喷药1次,连续喷药2次,防治效果均在90%以上。 相似文献
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茉莉花是我国音制花茶的主要香花原料。因此，近两年来我们在闽北建阳、政和等地花区对茉莉梢、蕾形成的基本特点，进行了观察试验为茉莉花化控高产栽培技术提供依据。一、幼蕾出现与蕾成熟观察表明，田间栽培的茉莉每年4月下旬至10月上旬均能陆续出现幼蕾。比较集中的蕾熟期为6月下旬到7月上旬的霉花；7月中旬到8月中旬的伏花；9月上旬到9月下旬的秋花，优花约占全年产量的50～60％、秋花占30～40％，霉花占5～10％。定技观察表明，从母枝派芽萌动到蕾成熟大致须经历四个时期：激动期、分化期、膨大期、完熟期。其历期分别为4～6天、7～9天… 相似文献
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泰国玉米笋植株形态与我国普通玉米相似,但它以腋芽长出指冰大小的玉米棒(形似小笋)为收获目的。采用幼嫩玉米棒精制而成的玉米笋罐头是目前国际盛行的一种新颖的蔬菜罐头之一。一、适时播种根据分期播种试验,泰国玉米笋在适时播种情况下,从播种至采笋为52-76天,因此,可根据罐头厂生产需要或市场蔬菜淡季,灵活安排播种期。从试验结果说明:3月下旬至9月中旬都可播种,平原地区一年可种三季,山区一般种植二季。春播从3月下旬至4月上旬为适期,播种至采笋为76-70天,采笋期15天左右;夏播从5月上旬至7月下旬,播种至采笋期65天左右;秋播从8月上旬至9… 相似文献
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发现六点始叶螨在海南岛一年可有23代,卵到成螨的发育期,成螨期和生活历期分别为8.7±0.7～28.4±2.4天,10.3±6.5～32.0±17.5天和19.2±5.1～55.6±13.7天。雌雄螨一生均能交配多次,每代平均产卵量为11.1±8.1～39.4±24.7个,雌螨一生的产卵量为1～114个,每个雌螨每天的产卵量为1～5个,卵的孵化率在95％以上,雌雄性比为1.8:1(雌螨/雄螨)。同一橡胶品系不同物候期的叶片对六点始叶螨的发育期,成螨期与产卵量有明显的影响,但品系的不同则无明显影响。 相似文献
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本研究以广西桂林柑桔园黑刺粉虱（Aleurocanthus spiniferus）为对象,采用田间调查该粉虱卵、若虫、蛹和成虫的方法,研究了该粉虱的种群消长规律。结果表明：广西桂林柑桔园每年3月中旬—12月上旬的气温可满足黑刺粉虱的生长发育需要,2015—2017年间黑刺粉虱种群变动较大,黑刺粉虱卵至蛹全年发生高峰在5月中旬—7月上旬,其次在8月下旬—9月上旬;而成虫全年发生高峰在5月上旬,其次则在9月上中旬。本研究表明每年5—9月是桂林柑桔园黑刺粉虱自然种群增长较快的时期,生产上应用密切关注这一时期的该粉虱种群动态,并根据其危害情况及时采取必要的防治措施。 相似文献
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《广东茶业》2015,(3)
目的:探明茶窗蛾的生活史及其习性,为防控此虫提供依据。方法:于茶园剪回有茶窗蛾幼虫的筒形叶苞枝梢,插在细口瓶中水培,置于有机玻璃器中饲养观察。结果:茶窗蛾在江西婺源一年发生6代,以蛹在表土落叶中越冬。翌年3月中旬成虫开始羽化产卵,卵第一代散产在茶芽或初展嫩叶尖端,2~6代产在叶正面(含叶边缘)。1~6代幼虫于3月下旬至5月上旬、5月中旬至6月上旬、6月下旬至7月中旬、7月下旬至8月中旬、9月上旬至9月中旬、10月上旬至11月上旬发生。幼虫卷筒形叶苞潜藏为害,每虫一生一般害嫩叶4~6片。各虫态历期为:卯5.0~1 3.7d、幼虫9.1~27.9d、预蛹1.6~3.7d、蛹8.3~1 3.9d、越冬蛹135.0~1 55.0d。成虫寿命3-3~10.3d。结论:茶窗蛾以幼虫卷叶苞为害,一年发生6代。 相似文献
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虱螨脲对棉铃虫的生物活性及应用研究 总被引：1，自引：0，他引：1
试验测定了虱螨脲对棉铃虫的室内生物活性和田闻防治效果。结果表明,虱螨脲具有较强的杀卵作用。在50mg／L浓度下。棉铃虫1日龄卵死亡率达到87．30％;对棉铃虫2～5龄幼虫具有较高的胃毒活性,其LC50分别为0．7434mg／L、1．9669mg/L、2．0592mg／L和2．6945mg／L。田间试验结果表明。在卵高峰期至初孵期用药,对棉铃虫有较高的防治效果,药后7d．用50g/L虱螨脲EC450mL/hm2、600mL／hm2防治效果分剐为89．3％、90．2％。 相似文献
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Lakshman Lal 《Potato Research》1987,30(2):329-334
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
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《Journal of Crop Improvement》2013,27(2):81-114
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
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Joseph E. Laferriere Charles W. Weber Edwin A. Kohlhepp 《Plant foods for human nutrition (Dordrecht, Netherlands)》1991,41(3):277-282
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
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M. I. Siri P. Villanueva M. J. Pianzzola L. Franco Fraguas G. Galván M. Acosta F. Ferreira 《Potato Research》2004,47(3-4):127-138
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
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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
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Alejandro Carlos Tozzini María Fernanda Ceriani María Verónica Saladrigas H. Esteban Hopp 《Potato Research》1991,34(3):317-324
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
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Rita Favas Janaína Morone Rosrio Martins Vitor Vasconcelos Graciliana Lopes 《Marine drugs》2022,20(3)
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
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Alejandro M. S. Mayer Abimael D. Rodríguez Orazio Taglialatela-Scafati Nobuhiro Fusetani 《Marine drugs》2013,11(7):2510-2573
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