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1.
建立了豇豆、土壤中吡虫啉测定高效液相色谱法,并研究吡虫啉在海南豇豆和其种植土壤中的消解动态以及在豇豆中的最终残留。结果表明:方法回收率为78%~89%,在0.05~5μg/mL线性关系良好,相对标准偏差(RSD)7%,最低定量限0.01μg/mL,方法满足检测工作要求。吡虫啉在豇豆和土壤中的半衰期分别为2.9、5.1 d。以1.5倍推荐剂量一次喷施农药2.5 d后吡虫啉残留量小于0.5μg/g。吡虫啉在土壤中半衰期较短,属于易降解农药;分别以1.5、2倍推荐剂量3次施药,每次施药间隔2d,自然降解4、6d后残留量均低于0.5μg/g。 相似文献
2.
滴灌量对冬小麦根系时空分布及水分利用效率的影响 总被引：3，自引：0，他引：3
为了解滴灌冬小麦根系生长及水分利用对滴灌量的响应,以新冬18号为材料,利用双管分根法比较分析了拔节期后4.24、6.12、8.01和9.89 kg·管-14种水分处理（每个处理灌水4次）下滴灌小麦根干重和根长的分布、0~100 cm土层含水量及产量和水分利用效率的差异。结果表明,加大滴灌量使0~100 cm土层湿润深度增加,尤其是提高了0~40 cm土层的含水量下限,并增加该土层的小麦初、次生根干重及根干重密度、根长及根长密度,延缓花后初、次生根干重密度的衰减。增加滴灌量显著提高小麦产量和水分利用效率。说明增加滴灌量可促进滴灌冬小麦拔节期至孕穗期根系生长,并延缓生育后期根系的衰亡,有利于产量和水分利用效率的提高。 相似文献
3.
在(25±1)℃、相对湿度(RH)70%±5%、光周期L∶D=13∶11条件下,用小叶龙船花花粉、豇豆花粉、扶桑花粉、台湾相思花粉、棉花花粉、玉米花粉饲喂卵圆真绥螨。结果表明,6种花粉饲喂均能使卵圆真绥螨完成生长发育及繁殖,其中豇豆花粉饲喂卵圆真绥螨时发育历期最短,为(5.07±0.06) d;存活率最高,为93.75%±3.05%;净增殖率最大,为16.78±1.22;单雌总产卵量第二,为(32.33±2.17)粒。综上所述,豇豆花粉较适宜卵圆真绥螨生长发育和繁殖。 相似文献
4.
为探索植物生长调节剂甲哌鎓、矮壮素在棉花控旺防徒长、增产等方面的调控效果，于2017年采用高喷雾量和常规量喷雾两种施药方式，分别于棉花初花期、盛花期和花铃期进行2～3次喷施，研究了98%甲哌鎓SP和50%矮壮素AS对棉花生长调控的影响。结果表明，98%甲哌鎓SP 73.5～117.6 g·hm－2和50%矮壮素AS 37.5～60 g·hm－2对棉花生长均有一定程度的调控作用，尤其对棉花株高、吐絮率、果枝数均有显著影响，且常规喷雾量处理对株高抑制效果优于高喷雾量处理。同时，二者均可显著提高棉花产量，改善棉纤维品质。相同施药方式下，甲哌鎓和矮壮素于棉花初花期、盛花期喷施2次对棉花生长调控效果更好。 相似文献
5.
三叶草斑潜蝇(Liriomyza trifolii Burgess)和美洲斑潜蝇(Liriomyza sativae Blanchard)是海南地区发生和危害比较严重的2种蔬菜潜叶蝇,通过对两种斑潜蝇在豇豆上的种群分布调查研究表明：三叶草斑潜蝇在豇豆上的种群数量达到了97%以上,已上升为豇豆上斑潜蝇的优势种;三叶草斑潜蝇主要集中在80 cm以上的空间,种群百分比达到了71.30%,美洲斑潜蝇主要集中在40～120 cm的空间,种群百分比为61.29%。种间竞争使得两种斑潜蝇在豇豆上空间生态位分布产生差异。 相似文献
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7.
豇豆不同类型间种子耐贮性差异 总被引：4，自引：0，他引：4
本文研究了不同类型豇豆种子经高温高湿（４０℃,１００％ＲＨ）老化处理后的发芽势,发芽率,发芽指数,活力指数和电导率的变化情况,结果表明,短荚豇豆亚种发芽各项指标下降率平均数以及相对电导率上升率平均数均比长荚豇豆亚种的低,因此,短荚豇豆亚种耐贮性比长荚豇豆亚种好。 相似文献
8.
为探讨不同温度下豇豆花粉对卵圆真绥螨[Euseius ovalis(Evans)]发育及繁殖的影响,在温度条件为25、30、35 ℃下,用豇豆花粉饲喂卵圆真绥螨,观察雌成螨繁殖,记录卵至成螨的发育历期,分析各螨态存活率及各生命参数。结果表明,用豇豆花粉饲喂卵圆真绥螨在3种温度下均可正常发育和繁殖,单雌总产卵量分别为(32.33±2.17)、(19.29±2.85)、(10.40±1.92)粒。卵-成螨30 ℃时发育历期最短,为(3.71±0.12) d。卵-成螨在25、30 ℃下存在较高的存活率,分别为93.75%±4.35%、90.63%±5.24%,35 ℃时存活率最低,为68.75%±8.30%。说明豇豆花粉可作为卵圆真绥螨的交替食物。35 ℃时,卵圆真绥螨的净增殖率、内禀增长率和周限增长率均为最低,分别为1.45±0.13、0.04±0.03和1.04±0.02,与25、30 ℃时存在显著差异,说明高温对卵圆真绥螨存在抑制作用。30 ℃种群加倍时间最短,为(3.73±0.56)d。 相似文献
9.
松嫩平原西部膜下滴灌种植方式下氮肥追施对玉米产量和氮素积累的影响 总被引：6，自引：0，他引：6
采用膜下滴灌种植方式,研究黑龙江大庆地区玉米基于叶龄指数管理的氮肥施肥次数及施氮量对玉米干物质积累、氮素利用率以及产量形成的影响。结果表明,在3次追肥(T3,叶龄指数30%、60%、100%等比例3次追肥)条件下、追氮量为120 kg/hm~2处理时,玉米子粒产量最高,为12 405.29 kg/hm~2,显著高于T3条件下其他追氮量处理,显著高于覆膜传统追肥处理和覆膜不施肥处理。在追氮量为120 kg/hm~2处理下,T3显著高于T2(叶龄指数30%和60%等比例2次追肥)和T5(叶龄指数30%、45%、60%、100%、抽雄吐丝后15 d等比例5次追肥)追肥处理(P0.05)。成熟期氮素吸收量表现为T3处理、追氮量150 kg/hm~2时最大,达241.82 kg/hm~2,比T2和T5追肥处理提高3.8%和1.6%,比T3处理下各追氮量处理提高0.6%~37%。 相似文献
10.
豇豆荚螟雌雄蛾求偶交配行为及其影响因子研究 总被引：1，自引：0，他引：1
通过红外监控系统和野外观察实验研究豇豆荚螟雌雄蛾求偶交配规律及其影响因子.结果表明,豇豆荚螟交配时雌、雄蛾尾部交合在一起呈"一"字形,交配时间一般为75 min.雌雄蛾羽化24 h后性成熟,黄昏入夜时分开始活动,求偶交配大部分发生在夜间21:00～03:00时段内.雌雄蛾求偶高峰期出现在凌晨01:00～02:00时段内,次高峰期出现在22:00～23:00时段内;而交配高峰期出现在凌晨02:00～03:00时段内,次高峰期出现在23:00～00:00时段内.雌雄蛾求偶交配高峰的蛾龄期为4日龄.雌雄蛾求偶交配的最佳性比为1:1.其最适宜求偶交配温度为22℃,补充10%的蜂蜜水能明显促进雌雄蛾的求偶交配,豇豆花挥发物对雌雄蛾的求偶交配行为具有显著的促进作用. 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
13.
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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15.
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
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.
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
18.
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
19.
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
20.
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