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A. Hanafi 《Potato Research》1999,42(2):373-380
Summary The potato tuber moth (PTM),Phthorimaea operculella (Zeller), is one of the most damaging pests of potatoes in field and storage. Tuber moth is active throughout the year in North Africa but is most active from late April to early August. Many cultural practices that are used by farmers to improve the yield and quality of potato can also limit the development of the potato tuber moth and minimise damage to tubers. As the farmers gain more experience with both agronomic practices and chemical insecticides, they are likely to rely more heavily on cultural practices and less on insecticides to manage PTM. Measures which could keep PTM damages in rustic and diffuse light stores to a minimum are discussed. Ideally, there is need to integrate pest management in potato fields and stores. PTM control in stores was found to be more effective if infestation in fields was kept to a minimum. Low infestation at harvest and rapid handling of the potatoes going into store established good initial storage conditions and decreased the likelihood of post-harvest losses. Biological insecticides in particular were more effective in preventing losses by insects in stores in cases where the initial level of infestation was relatively low.  相似文献   
3.
The effect of the chloronicotinyl insecticide (thiacloprid 480 SC) was evaluated to determine its potential in controlling the potato tuber moth, Phthorimaea operculella. Application of thiacloprid at various concentrations (0.1–0.4 ml/l) on different age groups of eggs (1–4.5 day-old) had no effect on egg hatchability. However, slight embryocidal effect was noted in all egg age groups exposed to 0.4 ml/l concentration. Egg incubation period was increased (20%) when 4–4.5 day-old eggs were treated with thiacloprid at a rate of 0.4 ml/l compared with the untreated control. Thiacloprid was effective in reducing larval survival on potato seedlings or adults emergence from potatoes, exhibiting activity for at least 14 days after application. When already infected potato seedlings or tubers were treated with thiacloprid at a rate of 0.4 ml/l, adult emergence was decreased. Larvae that hatched from thiacloprid-treated eggs and fed, untreated tubers, encountered some difficulties in surviving and emerging as adults. Our data suggest that potato plants or tubers treated with thiacloprid at a commonly used rate (0.4 ml/l) should be well protected from the possibility of infestations by the potato tuber moth. Publication of this article was held up owing to technical problems. The publisher apologizes sincerely for this lengthy delay.  相似文献   
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BACKGROUND: Pyrethroids are among the most potent pesticides known, with great potential for structural variation with retention or enhancement of potency. The simple methyl ester is easier to prepare (at least one step shorter) than the more complex pyrethroids modified on the alcohol moiety. The objective was to synthesise methyl esters of pyrethroid acids containing an aromatic ring on the acid moiety and evaluate their biological activity against Ascia monuste orseis Latr., Tuta absoluta Meyrick, Periplaneta americana (L.), Musca domestica L. and Sitophilus zeamais (Motsch.). RESULTS: The synthetic sequence required seven steps: protection of the hydroxyl groups of D ‐mannitol, diol oxidative cleavage with sodium metaperiodate, alkene formation by Wittig reaction with methoxycarbonylmethylidene(triphenyl)phosphorane, cyclopropanation, acetal hydrolysis with perchloric acid and oxidative cleavage with sodium metaperiodate gave methyl (1S, 3S)‐3‐formyl‐2,2‐dimethylcyclopropane‐1‐carboxylate. The final step comprised reaction of the aldehyde with five different aromatic phosphorus ylides to give the pyrethroids. CONCLUSION: An efficient and versatile synthesis of ten new pyrethroid methyl esters has been accomplished from the readily available D ‐mannitol in seven steps. All compounds showed insecticidal activity, and methyl (1S, 3S)‐3‐[(Z)‐2‐(4‐chlorophenyl)vinyl]‐2,2‐dimethylcyclopropane‐1‐carboxylate was the most active, killing 90% of A. monuste orseis and 100% of T. absoluta and P. americana. Copyright © 2009 Society of Chemical Industry  相似文献   
5.
Summary Recent research, reviewed here, of the pheromone system of the potato tuberworm moth has led to the isolation, identification, and synthesis of its components.trans-4,cis-7-tridecadien-l-ol acetate (PTM 1) andtrans-4,cis-7,cis-10-tridecatrien-l-ol acetate (PTM 2), mixtures of which are much more attractive in the field than 2 virgin female moths or each compound on its own.  相似文献   
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Summary Both the amount and frequency of irrigation were based on evaporation from a screened USWB Class A pan. From the time tuber initiation had been completed, and full cover had been attained (about 60 days after planting), until the crop was lifted, 40–60 days later, sprinkler irrigation with the equivalent of 0.7–0.8 of pan evaporation was sufficient for maximum yields. However, with trickler irrigation 20% more water was required, perhaps due to percolation losses under the tricklers. Irrigating by sprinkler whenever 25 mm of pan evaporation had accumulated was sufficient although irrigating at 12.5 mm further increased yield somewhat. However, daily irrigation by tricklers did not increase yields compared to irrigating whenever 25 mm of pan evaporation had accumulated (every 4–5 days). Trickler irrigation was found unsuitable for potatoes because the soil cracked and exposed the tubers to attack by the potato moth (Phthorimaea operculella).
Zusammenfassung In Zypern wird die Hauptmenge an Kartoffeln auf Terra rossa Tonb?den in Kokkinochoria, einer Küstenregion, gepflanzt (Tab. 2). Das Legen erfolgt von Mitte Dezember bis Mitte Februar, was mit der Regenzeit über-einstimmt (Tab. 1). Das Auflaufen und der Knollenansatz finden daher bei ausreichender Bodenfeuchtigkeit statt. Ab Februar regnet es jedoch zu wenig und zu unregelm?ssig, der Bestand muss beregnet werden (Abb. 1). Das wird fast ausschliesslich mit fahrbaren Sprengern (sprinkler) gemacht. Es wird über die Ergebnisse von fünf Versuchen berichtet, davon drei mit Sprengern und zwei mit Tr?pfchenberegnern (trickler). Sowohl die Menge als auch die H?ufigkeit der Bew?sserung beruhten auf der Verdunstung, die mit einer vom Wetterdienst der Vereinigten Staaten (USWB) geprüften Verdunstungsplatte Klasse A gemessen wurde (Abb. 1). Bew?ssert wurde vom Ende des Knollenansatzes und Bestandsschlusses (ungef?hr 60 Tage nach dem Legen) bis zur Ernte, 40–60 Tage sp?ter (Abb. 1). Bei einer Beregnung mit dem Sprenger war eine Wassermenge, die einem Wasser?quivalent von 0,7–0,8 der Verdunstung entsprach, für H?chstertr?ge ausreichend (Abb. 2). Bei der Tr?pfchenberegnung war jedoch 20% mehr Wasser erforderlich (Abb. 2, Tab. 4), vielleicht wegen der Versickerungsverluste unter den Beregnern. Die erh?hten Ertr?ge, die durch die gesteigerte Wassermenge entstanden, ergaben sich durch gr?ssere Knollen (Abb. 3). Gleichzeitig nahm das spezifische Gewicht linear mit der steigenden Wassermenge geringfügig ab (Tab. 3). Wasserüberschuss führte zu grossen Lentizellen und gelegentlich zu inneren und ?usseren Rissen der Knollen (Abb. 4). Eine Beregnung durch Sprenger nach einer Verdunstung von 25 mm, was einer Verringerung des verfügbaren Wassers um 54% in den ersten 30 cm des Bodens entsprach, genügte, obwohl eine Bew?sserung nach weiteren 12,5 mm den Ertrag geringfügig erh?hte (Abb. 2). Eine t?gliche Bew?sserung durch Tr?pfchenberegnung erh?hte im Vergleich zur Beregnung nach 25 mm Verdunstung (jeden 4–5 Tag) den Ertrag nicht. Bei Tr?pfchenberegnung, aber nicht bei Beregnung durch Sprenger, brach der Boden auf und erm?glichte den Befall der Knollen durch die Kartoffelmotte (Phthorimaea operculella).

Résumé A Chypre, une grande partie des pommes de terre est cultivée dans une région c?tière, le Kokkinochoria, sur des sols argileux (terra rossa) (tableau 2). La plantation se fait sur toute la période de mi-décembre à mi-février, ce qui co?ncide avec la saison pluvieuse (tableau 1). La levée et la tubérisation ont normalement lieu dans des conditions d'humidité suffisante du sol. Mais à partir de février, la pluviométrie est insuffisante et irrégulière (fig. 1) et il faut irriguer la culture, ce qui est fait presque exclusivement avec des sprinklers mobiles. Voici le compte-rendu des résultats de 5 essais, 3 avec sprinklers et 2 avec goutte à goutte. La dose et la fréquence de l'irrigation ont été établies à partir de l'évaporation d'un bac sous abri classe A du bureau météorologique américain (USWB) (fig. 1). L'irrigation a été effectuée à partir de la fin de l'initiation des tubercules et lorsque la couverture complète du sol était atteinte (environ 60 jours après plantation), jusqu'à la récolte, c'est à dire 40 à 60 jours plus tard (fig. 1). Avec les sprinklers, l'apport de l'équivalent de 70 à 80% de l'évaporation du bac était suffisant pour atteindre un rendement maximum (fig. 2). Mais avec le goutte à goutte, il fallait 20% d'eau en plus (fig. 2, tableau 4), surement à cause des pertes par percolation sous les goutteurs. Les augmentations de rendement obtenues avec les quantités croissantes d'eau étaient d?es au grossissement des tubercules (fig. 3). Le poids spécifique des tubercules diminuait légèrement mais linéairement avec les doses croissantes d'eau (tableau 3). L'irrigation en excès a fait appara?tre de larges lenticelles et a provoqué occasionnellement des éclatements internes ou externes des tubercules (fig. 4). L'irrigation par sprinklers, chaque fois que 25 mm d'eau s'étaient évaporés du bac, était suffisante, ce qui correspond à une diminution de 54% de la réserve utilisable dans les 30 premiers centimètres du sol. Cependant, l'irrigation supplémentaire à 12,5 mm a augmenté un peu le rendement (fig. 2). Mais l'irrigation journalière par goutte à goutte n'a pas augmenté les rendements par rapport à l'irrigation chaque fois que 25 mm d'eau s'étaient évaporés du bac (tous les 4 à 5 jours). Avec l'irrigation goutte à goutte, mais pas avec les sprinklers, le sol se craquelait, exposant les tubercules aux attaques de la teigne (Phthorimaea operculella).
  相似文献   
7.
BACKGROUND: The tomato leafminer (Tuta absoluta Povolny) has rapidly colonised the whole Mediterranean and South‐Atlantic coasts of Spain, and it has become a key problem in both outdoor and greenhouse crops. New control methods compatible with biological control are required, and mating disruption appears to be a perfect method in current agriculture, as it is an environmentally friendly and residue‐free technique. IPM packages tested have included the use of pheromones to detect populations, but there has not been much previous research on mating disruption of T. absoluta. In this work, pheromone doses varying from 10 to 40 g ha?1, emitted at a constant rate over 4 months, were tested in greenhouses with different levels of containment in order to evaluate the efficacy of mating disruption on T. absoluta. RESULTS: Trials on containment level revealed that the flight of T. absoluta was satisfactorily disrupted with an initial pheromone dose of 30 g ha?1, and levels of damage did not significantly differ from those in reference plots with insecticide treatments. Later efficacy trials confirmed previous experiences, and release studies showed that control of damage and flight disruption were taking place when releasing at least 85 mg pheromone per ha per day. CONCLUSION: Effective control using pheromone application against T. absoluta can be achieved, in greenhouses with high containment levels, for 4 months, with initial doses of 30 g ha?1. Further research must be conducted in order to evaluate the prospect of outdoor application of mating disruption systems. Copyright © 2011 Society of Chemical Industry  相似文献   
8.
室内测定了从云南分离的7株球孢白僵菌对马铃薯块茎蛾幼虫的毒力,结果表明,在接菌孢子浓度为105个/mL和107个/mL下,接种后7d马铃薯块茎蛾幼虫累积死亡率分别为23.3%~70.0%和33.3%~86.7%,添加吐温80的清水对照死亡率仅为3.3%。筛选出毒力较高的Bb7001、Bb7004、Bb8001 3个菌株,其中菌株Bb8001对马铃薯块茎蛾幼虫的毒力最高,在孢子浓度1×105、1×107个/mL下,第7天的累计死亡率分别为70.0%和86.7%,其毒力回归方程Y=0.366X+3.409(R=0.956),剂量效应LC50=2.24×104个/mL,孢子浓度107个/mL下的LT50为4.3d。测定了毒力较高的菌株与12种农药的生物相容性,结果表明在供试农药推荐用量及其101、00倍稀释液下,球孢白僵菌Bb7001、Bb7004、Bb8001的3个菌株孢子在含所选农药的营养液中生物相容性良好的农药有:苏云金芽孢杆菌可湿性粉剂(Bt)、10%吡虫啉可湿性粉剂、2.5%菜喜悬浮剂及松毛虫病毒可湿粉剂,可配伍使用;而阿维菌素、农安、卡死克、抑太保对球孢白僵菌有很强的抑制作用,应避免配伍使用。  相似文献   
9.
Phthorimaea operculella (Zeller) is a worldwide pest of potato. Plant-borne chemicals would be potential alternatives of synthetic chemical fumigants against P. operculella in the storage. Asari Radix et Rhizoma is derived from the dry roots and rhizomes of Asarum heterotropoides Fr. Schmidt var. mandshuricum, A. sieboldii Miq. var. seoulense, or A. sieboldii. In this study, fumigant toxicity and oviposition deterrent of volatile constituents from ARR, δ-3-carene, γ-terpinene, terpinolene, eucarvone, 3,5-dimethoxytoluene, and methyleugenol were tested against P. operculella. The preliminary verification of preventive and control effects of eucarvone, 3,5-dimethoxytoluene and methyleugenol on P. operculella was carried out by simulating warehouse experiments. The results indicated that the six compounds above had fumigation toxic effects on the adults and eggs of P. operculella. Among them, δ-3-carene, γ-terpinene, and terpinolene had weaker fumigation effects than those of eucarvone, 3,5-dimethoxytoluene, and methyleugenol. The LC50 values of eucarvone, 3,5-dimethoxytoluene, and methyleugenol against adult P. operculella were 1.01, 1.78, 1.51 mg/liter air, respectively. The LC50 values against egg P. operculella were 1.09, 0.55, 0.30 mg/liter air, respectively. The oviposition deterrent experiment showed that only methyleugenol (at 5 and 1 mg/ml) and eucarvone (5 mg/ml) had a substantial oviposition deterrent effect. The simulated warehouse experiment verified that methyleugenol, eucarvone, and 3,5-dimethoxytoluene protected potatoes from P. operculella and demonstrated that methyleugenol had the best preventive and control effects. It was concluded that methyleugenol was the active ingredient with the most potential in the volatiles from ARR on P. operculella control and merit further study as botanic fumigant.  相似文献   
10.
【目的】通过行为观察揭示物理与化学因素联合作用对马铃薯块茎蛾(Phthorimaea operculella)产卵行为的影响,为马铃薯块茎蛾行为调控技术的发展提供依据。【方法】将新鲜马铃薯块茎分别用药液(庚醛、桉叶油醇)浸泡后晾干、用纱布或浸透块茎汁液的纱布包裹块茎,之后在温度(27±2)℃,相对湿度50%—70%,光周期L:D=14:10环境条件下,于暗期(光照强度1.0—1.5 lx)观察马铃薯块茎蛾已交配雌虫在马铃薯块茎上产卵行为表现(包括滞留时间、降落次数、试探产卵次数和落卵量)。【结果】当用低浓度庚醛溶液(0.5 mg·L-1)处理块茎后,可显著延长雌蛾在块茎上的滞留时间,导致总落卵量(块茎上落卵量+块茎外落卵量)增加,但是不会引起试探产卵次数和降落次数的明显变化。当用庚醛溶液(30 mg·L-1)处理块茎后,能够引起滞留时间、降落次数和试探产卵次数的显著降低,并导致总落卵量显著增加。当用低浓度桉叶油醇(6 mg·L-1)处理块茎后,可导致块茎上落卵量显著增加,但滞留时间、降落次数及试探产卵次数均无显著差异。当用高浓度桉叶油醇溶液(30 mg·L-1)处理块茎后,可显著降低雌蛾在块茎上的滞留时间、降落次数和试探产卵次数,同时引起块茎外的落卵量显著增加,但不会引起总落卵量的明显变化。当用纱布包裹块茎后,会显著降低雌蛾的降落次数、试探产卵次数,但不会显著改变滞留时间,块茎上的落卵量以及总落卵量均显著增加。当用浸有块茎汁液的纱布包裹新鲜块茎后,亦获得类似结果。当用含有庚醛(0.5 mg·L-1)的纱布处理块茎后,与空白对照相比,可显著增加雌蛾在块茎上的滞留时间和块茎上的落卵量,同时显著减少雌蛾的试探产卵次数、降落次数;与单一使用庚醛(0.5 mg·L-1)相比,可显著减少雌蛾的试探产卵次数、降落次数,同时显著增加雌蛾在块茎上的落卵量和总卵量;与单一使用纱布处理相比,在各项指标上均无显著性差异。【结论】庚醛能够刺激已交配雌蛾在更加密集的时间产卵;在浓度为30 mg·L-1时,庚醛对已交配雌蛾具有驱赶作用;在浓度为0.5 mg·L-1时,庚醛对已交配雌蛾具有吸引作用。桉叶油醇溶液浓度为30 mg·L-1时,对马铃薯块茎蛾产卵仅有驱赶作用。纱布包裹、纱布浸透块茎汁液、6 mg·L-1桉叶油醇溶液仅有刺激已交配雌蛾在更加密集的时间产卵的作用。化学刺激(0.5 mg·L-1庚醛)结合物理刺激(纱布)是纱布刺激产卵作用和0.5 mg·L-1庚醛吸引作用的叠加作用。  相似文献   
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