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1.
药材甲[Stegobium paniceum(L.)]是中药材储藏期害虫优势种,对我国储藏中药材造成极大危害。此虫卵小,椭圆形,长径296.80~380.80μm,短径224.00~313.60μm。幼虫有4个龄期,1~2龄体小,3~4龄体长迅速增加,整个幼虫期蛀食生存于药材中。蛹被蛹室,长5~10 mm,发育过程中伴随颜色变化。成虫体长2~6 mm,羽化后2~3 d交配产卵,单雌卵量(55.78±3.01)粒,寿命(22.22±1.39)d。1年发生3~4代,世代重叠明显,多以当年第4代幼虫越冬。  相似文献   

2.
菜小脉蚜茧蜂发育速率与温度及寄主龄期关系研究   总被引:1,自引:0,他引:1  
刘树生 《昆虫天敌》1989,11(4):169-173
以桃蚜Myzus persicae为寄主,测定了菜小脉蚜茧蜂Diaeretiella rapae在不同温度及不同龄期寄主中的发育速率。算得该蜂的发育起点温度t=8.76±0.13℃,有效温积常数K=139.51±1.60日度。在不同龄期无翅蚜虫中平均发育速率有显著差异,依次为:三龄>四龄>二龄>成蚜>一龄,最快与最慢相差5%。进一步的分析表明,不同龄期对蜂发育适合性的这种差异是由于个体大小不一和内含物营养不同两方面综合导致的  相似文献   

3.
为明确不同寄主饲养的瓜实蝇Bactrocera cucurbitae (Coquillett)幼虫与蛹的低温耐受性差异, 选择西葫芦Cucurbita pepo、节瓜Benincasa hispida和黄瓜Cucumis sativus饲养多代的瓜实蝇老熟幼虫和不同日龄的蛹, 分别测定其过冷却点、结冰点和在不同低温下的存活率, 并进行比较分析。结果表明:取食不同寄主植物的瓜实蝇老熟幼虫过冷却点无显著差异, 取食节瓜的老熟幼虫的结冰点[(-5.33±0.23)℃]最低, 且与取食黄瓜的种群没有显著差异;取食节瓜的蛹的过冷却点与结冰点均最低, 其中1日龄、3日龄和5日龄蛹的过冷却点和结冰点分别为(-19.28±0.30)℃ 和 (-15.06±0.34)℃, (-20.97±0.40)℃ 和(-17.33±0.39)℃, (-20.08±0.46)℃ 和 (-16.39±0.46)℃。取食节瓜和黄瓜的老熟幼虫在3、6℃和9℃下暴露1 d, 其存活率均显著高于取食西葫芦的老熟幼虫;节瓜种群的1日龄蛹在3℃和9℃下暴露1 d时, 其存活率都显著高于黄瓜和西葫芦种群的1日龄蛹的存活率。寄主植物可影响瓜实蝇的过冷却点、结冰点及低温存活能力, 与其他寄主种群相比,瓜实蝇节瓜种群老熟幼虫和蛹对低温的适应能力更强。  相似文献   

4.
麦蛾茧蜂是鳞翅目昆虫的一种外寄生蜂,是仓储鳞翅目害虫的重要寄生性天敌。为提高麦蛾茧蜂的扩繁效率,本文在室内条件下研究了其寄主烟草粉螟密度、麦蛾茧蜂密度和性比对其子代出蜂数(雌蜂数、雄蜂数和总蜂数)和雌雄性比的影响。结果表明,当烟草粉螟密度为5头/盒时,麦蛾茧蜂的子代出蜂雌蜂数、雄蜂数、总蜂数和雌雄性比最高,分别为(90.71±2.01)、(51.70±2.95)、(142.00±3.88)头和(1.79±0.11);当烟草粉螟密度为50头/盒而麦蛾茧蜂密度不同时,4对寄生蜂(蜂与害虫比为1∶12.5)的平均单雌出蜂数最高;此外,增加雌蜂数显著提高子代出蜂数,而增加雄蜂数并未显著影响这些指标。因此,本文推荐在麦蛾茧蜂的大量饲养中,按寄生蜂、害虫比为1∶5~1∶12.5、寄生蜂雌雄性比为1∶1的方式接蜂且可连续使用10 d,这将有利于麦蛾茧蜂的大量饲养。该研究结果可为麦蛾茧蜂的规模化繁育和应用提供技术参数。  相似文献   

5.
茶尺蠖幼虫期的重要寄考性天敌一单白绒茧蜂在14和34℃恒温下,供以寄主,无子蜂羽化。在18~30℃下,其幼期(卵-蛹)一般随温度上升而缩短,反之则延长,发育起点温度为9.98±2.78℃日度。由此在杭州年可发生11-13代。成虫寿命则随温度升高而下降,自然变温下趋势一致。寄主虫龄对该的卵+幼虫期无显著影响,而在寄主体外的预蛹+蛹的历期则随寄主虫龄增大而缩短。  相似文献   

6.
樟子松在西北干旱沙区的光合日变化特征   总被引:7,自引:0,他引:7  
在甘肃省民勤治沙站 ,用 Li- 62 0 0便携式光合仪分别测定人工栽植的 4龄、9龄和 2 0龄樟子松的净光合速率日进程 ,其结果表明 :在干旱沙区 ,9龄以上樟子松的光合速率在午前随光强和气温而上升 ,午后下降。其 4龄、9龄和 2 0龄樟子松的最大净光合速率分别为 8.7μmol· m- 2 · s- 1、62 .3μmol· m- 2 · s- 1、1 9.7μmol· m- 2 · s- 1。  相似文献   

7.
丽草蛉幼虫对草地贪夜蛾卵及低龄幼虫的捕食能力评价   总被引:1,自引:0,他引:1  
为明确优良天敌丽草蛉对重大入侵害虫草地贪夜蛾的控害潜能,本研究测定了丽草蛉幼虫对草地贪夜蛾卵和低龄幼虫的捕食能力及其功能反应,观察并总结了其捕食行为特点。结果表明,丽草蛉2龄、3龄幼虫对草地贪夜蛾卵及1~2龄幼虫均具有较强的捕食能力,其2龄幼虫日均捕食猎物卵(30.2±6.8)粒、1龄幼虫(22.2±5.6)头,3龄幼虫对猎物1龄幼虫的捕食量最高,为(66.8±13.3)头,其次是对卵和2龄幼虫,捕食量分别为(46.2±8.9)粒和(10.95±1.2)头。丽草蛉幼虫对不同虫态草地贪夜蛾的捕食量随猎物密度增加逐渐升高后趋于稳定,符合Holling Ⅱ功能反应模型。3龄幼虫对草地贪夜蛾的搜寻处理能力、捕食速率及最大捕食量均显著优于2龄幼虫,控害效能更强。本研究结果为利用丽草蛉持续控制草地贪夜蛾提供了重要参考依据。  相似文献   

8.
测定手采新鲜的芍药花粉、芍药长木蜂Xylocopa tranquebarorum(Swederus)花粉和不同酿制时间蜂粮样品的平均pH值,结果分别是6.19、5.92和4.05(40日龄蜂粮)。随着酿制时间的延长,蜂粮的pH值下降,2日龄蜂粮到3日龄蜂粮的pH值从5.57降至4.82,下降速率明显。经测定,紫藤长木蜂花粉和不同日龄蜂粮样品中紫藤花粉的纯度均在98%以上;芍药长木蜂花粉和不同日龄蜂粮样品中芍药花粉的纯度均在93%以上;测定紫藤花粉的长木蜂蜂粮和芍药花粉的长木蜂蜂粮中的花粉活力。结果表明,在1日龄蜂粮中花粉活力基本丧失,3日龄后均失去萌发力,并且不同的花粉蜂粮其花粉活力表现一致。  相似文献   

9.
烟蚜茧蜂对蚜虫选择性的数量测定   总被引:1,自引:0,他引:1  
王文夕 《植物保护》1990,16(Z1):18-19
本试验通过对烟蚜茧蜂(Aphidius gifuensis)产卵选择性的研究,认为:(1)对于麦长管蚜(Sitobion.avenae)和麦缢管蚜(Rhopalosiphum padi),烟蚜茧蜂喜欢产卵于麦长管蚜;(2)对于麦长管蚜的不同龄期,烟蚜茧蜂喜欢产卵于麦长管蚜的二—三龄若蚜。  相似文献   

10.
研究了阿里山潜蝇茧蜂Fopius arisanus(Sonan)的老熟幼虫、不同日龄的蛹(1 d、5 d、9 d)以及不同日龄成蜂(1 d、7 d、14 d、21 d)的过冷却点和结结冰点,结果显示阿里山潜蝇茧蜂5 d龄蛹的过冷却和结结冰点最低,而老熟幼虫最高,且老熟幼虫的SCP、FP值变化幅度均最窄;不同日龄雌雄成蜂的过冷却点和结结冰点均是7 d龄最低,21 d龄最高;相同日龄,雌蜂的过冷却点和结结冰点均低于雄蜂。  相似文献   

11.
The molecular weight pattern and the stage-specific activities of chitinases from the blowfly Lucilia cuprina, the tick Boophilus microplus and the intestinal nematode Haemonchus contortus were examined. Chitinolytic enzymes could be detected in all parasite species tested, but the activity was different between the stages. Highest chitinolytic titers were found in blowfly pupae (83 kDa, 118 kDa), hatching larvae of ticks (58 kDa, 94 kDa) and nematode eggs (43 kDa). Leaves from ethylene-treated bean plants Phaseolus vulgaris expressed two basic Class I chitinases (Ia, Ib) of 34 kDa, differing in their amino acid sequences at residue 33 and 34 (Ia: glycine, proline; Ib: lysine, aspartic acid). Inhibitor studies with blowfly pupae revealed that allosamidin (IC50=0·32 (±0·02) μM ) was by far the best inhibitor when compared with various amino sugar derivatives. This compound also inhibited chitinases from tick larvae (IC50=0·69(±0·10) μM ) and nematode eggs (IC50=0·048(±0·0045) μM ) specifically. Whereas Class Ia chitinase from bean leaves was inhibited only up to 18% by 10 μM allosamidin, it had an IC50 of 1(±0·14) μM for the Ib type, which is the first plant chitinase described to be highly sensitive to allosamidin.  相似文献   

12.
A muscarinic acetylcholine receptor (mAChR) has been demonstrated and partially characterized in larvae of the cattle tick Boophilus microplus. Its properties are compared with mAChR from an epithelial cell line from the dipteran insect Chironomus tentans. Competition studies with cholinergic ligands of different specificity revealed the muscarinic nature of the cholinergic receptors investigated in both species. In homogenates from tick larvae, specific binding sites for [3H]quinuclidinyl benzilate (QNB) with high affinity (1·2±(0·13) nM ; Bmax 22·5 pmol mg protein−1) were detected that do not bind nicotinic compounds specifically. The estimated IC50 values for nicotine, imidacloprid and α-bungarotoxin were all in the mM range. Additionally, with tick larvae, high-affinity nicotinic binding sites were detected with [3H]nicotine which could be displaced by high concentrations of imidacloprid or QNB. The estimated IC50 values for nicotine, α-bungarotoxin, imidacloprid and QNB were 43(±8) nM , 0·8(±0·2) μM , 2·8(±0·6) μM and 78(±1·9) μM , respectively. With homogenates of the non-neuronal insect cell line from C. tentans, only high-affinity binding sites for [3H]QNB were found. Muscarinic antagonists selectively displaced [3H]quinuclidinyl benzilate (QNB) binding to tick larvae homogenates. The mAChR of B. microplus preferred pirenzepine (IC50 2·13(±1·02) μM ) among different subtype-specific mAChR antagonists (4-DAMP had IC50 49·9(±9·13) μM and methoctramine had IC50 121(±14·2) μM ) indicating a type of binding site similar to the vertebrate M1 mAChR subtype. The tick muscarinic receptor seems to be a G-protein-coupled receptor, as concluded from the 4·8-fold reduction in receptor affinity for binding of the muscarinic agonist oxotremorine M upon treatment with the non-hydrolysable GTP-analogue γ-S-GTP. Binding data for the agonists oxotremorine M (IC50 71·3(±19·6) μM ) and carbachol (IC50 253(±87·1) μM ) parallel the biological efficacy of these compounds, in that, while oxotremorine M showed some activity against ticks, carbachol was ineffective.  相似文献   

13.
The potential of known and new insecticides to interfere with cuticle sclerotization was investigated using assays for key enzymes such as phenoloxidase, quinone methide isomerase and DOPA decarboxylase. Homogenates from the blowfly Lucilia cuprina and from the epithelial cell line from Chironomus tentans were used to examine the compounds under investigation. Phenoloxidases are known to oxidize DOPA, the substrate for DOPA decarboxylase. Since phenoloxidases were not detectable in C. tentans cell homogenates, inhibitor and kinetic studies were done for comparison with DOPA decarboxylase of this insect cell line. DOPA decarboxylase and phenoloxidase of L. cuprina exerted highest specific activities at early pupal stages (day 7). The apparent Km values for the two enzymes were 0·47(±0·21) mM and 0·71(±0·16) mM , respectively, using L -DOPA as substrate. DOPA decarboxylase from C. tentans had a Km value of 0·42(±0·18) mM . Quinone methide isomerase was most active in young pupae. In terms of substrate specificity for enzymic (mushroom-tyrosinase) production of different quinones from their corresponding catechols, that with dopamine quinone proved to be the most efficient. Synthesis of derivatives of L -DOPA and L -tyrosine led to a compound which inhibited both phenoloxidase and quinone methide isomerase. DOPA decarboxylase from L. cuprina and from cells of C. tentans was inhibited by carbidopa (IC50 values of 0·021(±0·011) μM and 0·031(±0·019) μM , respectively) and indomethacine (IC50 values of 22·6(±7·1) μM and 18·8(±9·7) μM ). Both compounds exerted a competitive type of inhibition and were able to interfere with development of L. cuprina.  相似文献   

14.
Disposition kinetics of cypermethrin and fenvalerate were investigated in lactating black Bengal goats following single dose intravenous administration at 57 and 45 mg kg?1 respectively. The maximum and minimum blood concentrations of cypermethrin were 18.49 (±3.17) and 0.06 (±0.002) μg ml?1, while the corresponding values for fenvalerate were 14.58 (±2.37) and 0.04 (±0.005) μg ml?1 respectively. Both cypermethrin and fenvalerate remained present in blood for 36 h. The mean t1/2β) and Vdarea values were 5.56 (±0.28) h and 10.38 (±2.20) litre kg?1 for cypermethrin and 5.66 (±0.35) h and 11.31 (±2.20) litre kg?1 respectively for fenvalerate. Both cypermethrin and fenvalerate persisted in goat milk for 36 h. The t1/2β) and AUC values of fenvalerate were 7.37 (±1.84) h and 122.38 (±11.65) μg h ml?1 whilst the corresponding values for cypermethrin were 6.66 (±1.54) h and 99.48 (±7.81) μg h ml?1 in milk respectively.  相似文献   

15.
A non-volatile oil-based spray mix of a low-vapour-pressure insecticide, aminocarb, containing an oil-soluble red dye was applied at a dosage rate of 70 g AI in 1-5 litre ha?1, using a fixed wing aircraft equipped with four ?Micronair’?® AU3000 atomizers, over a 1000 × 500 m spray block selected in Bathurst, New Brunswick, Canada. Spray was applied twice, at an interval of five days, to provide a total dosage rate of 140 g AI in 3.0 litre ha?1. Spray mass recovery was assessed on glass plates and droplets were collected on ?Kromekote’?® cards, both at ground level. The stain sizes were grouped into different categories. The area containing the stains was excised, and the aminocarb present was quantified by gas-liquid chromatography (GLC). The mass of aminocarb per droplet in each stain size category was evaluated. From the mass, the spherical droplet diameter (d), number and volume median diameters (DN.5 and Dv.5 respectively), a new parameter [mass (of aminocarb) median diameter] (DM.5), and the droplet size spectra were calculated. The DM.5 for the first application was 56 μm, which was identical to the Dv.5. whereas the DN.5 was smaller at 45 μm. The corresponding values for the second application were: DM.5 = Dv.5 = 63 μm, but the DN.5 was 53 μm. Because the spray mix was non-volatile, all the droplet size spectra parameters were identical both at spray release height and at ground level. The present study has provided, for the first time in the literature, a novel method to determine directly the spherical diameters of the droplets deposited on artificial samplers, without having to go through the tedious procedures of spread factor measurements under laboratory conditions. In fact, the present study has made it possible to calculate spread factors under field conditions, by using the stain diameters measured and the spherical diameters calculated from the aminocarb concentration levels.  相似文献   

16.
Photochemistry of the herbicide 3,5-dibromo-4-hydroxybenzonitrile (bromoxynil) (I) was investigated by irradiating at approximately 313 nm. Aqueous phase photoreactions of 0.078–7.800 × 10?5m solutions of I were carried out at different pH values. Quantum yields for the loss of I in buffered solutions were 0.008 (±0.0004), 0.048 (±0.0024), and 0.044 (±0.0022) at pH 2.6, 7.0, and 11.0, respectively. In neutral and basic conditions, I absorbed more strongly at wavelengths > 290 nm, an environmentally significant region. Phototransformation of I was monitored by HPLC and UV-VIS spectrometry. All photoreactions of I gave rise to the generation of two products, 3-bromo-4-hydroxybenzonitrile and 4-hydroxybenzonitrile. The former photoproduct was tentatively identified from its mass spectral data. The photoproducts can be accounted for with a proposed mechanism involving free radicals.  相似文献   

17.
Thirty-five strains ofVerticillium lecanii which originated from different hosts and geographical locations were tested as potential biocontrol agents against silverleaf whitefly,Bemisia argentifolii Bellows & Perring. All strains were tested for their pathogenicity to third-instar nymphs. Several isolates which exhibited high pathogenicity to nymphs were also tested against eggs, pupae and adults ofB. argentifolii. Eggs were found to be immune to infection, but mortality of hatching nymphs reached 95–98%. The rate of hatching nymphs’ infection depended on the age at which the eggs were inoculated and the strain’s virulence. Mortality of nymphs recorded on day 4 after inoculation varied from 0.5±0.3% to 83±2.4%; that of the control ranged from 2.5% to 10.2%. The most virulent strains, with LT50 ranging between 3.2 and 3.8 days, were isolated from aphids in Israel and probably have a similar origin. The pathogenicity ofV. lecanii strains to pupae 6 days after inoculation varied between 59± 12.1 % and 72.5± 13.1 %, as compared with natural mortality of 13.5±4%. The maximum adult mortality caused byV. lecanii strains was between 34.1±5.1% and 52.6±3.8%.  相似文献   

18.
Aerial spray applications of the herbicide glyphosate were made over a forest canopy under various meteorological conditions. A ‘Thru Valve Boom’ dispersal system carried by a Cessna 188 fixed-wing aircraft flying at 49 m s?1 was used to generate an aqueous spray cloud with a volume median diameter of 150 μm. Glyphosate deposits from multiple overlaid crosswind line sources released at 10 m above ground level were measured on ground sheets and artificial foliage at downwind distances between 50 and 400 m. Trials were conducted in stable, neutral and unstable atmospheric boundary layers with average wind speeds between 2·2 and 5·7 m s?1 and vertical intensities of turbulence between 0·07 and 0·16. Linear regression lines fitted to logarithmically transformed measurements and downwind distances (x) gave statistically significant correlation coefficients (P = 0·01), and were compared by ANOVA. Glyphosate deposits on ground sheets and artificial foliage were attenuated at rates inversely proportional to x to the power 1·7-4·3. Regression line comparison showed that, in general, deposits on ground sheets decreased with increasing wind speed and intensity of turbulence, and some statistically significant differences were found in slopes and elevations of regression lines from different trials. However, deposits at the 50-m station increased with wind speed due to the large-drop cloud component. Regression line comparison for deposits on artificial foliage showed that, in general, they were highest in the intermediate wind speed-neutral stability case and similar in the high wind speed-unstable and low wind speed-stable boundary layers, although deposits at the 50-m station also increased with wind speed.  相似文献   

19.
BACKGROUND: Rose‐ringed parakeets Psittacula krameri (Scop.) have recently become established in several European countries, with potential for significant negative economic and ecological impacts. However, in northern Europe the potential for reproductive output is largely unknown. In 2005 the authors established a captive outdoor colony in north‐east England and examined breeding success over 2 years. RESULTS: In 2006 (19 pairs, 15 clutches) the average first clutch size was 3.6 (±0.3) eggs. Six clutches were infertile, and overall the colony produced 1.4 (±0.5) fertile eggs per pair. Eleven pairs produced a second clutch following removal of the first; seven were infertile, and overall productivity was 0.7 (±0.4) fertile eggs per pair. Unsuccessful pairs were rearranged or replaced. In 2007, overall productivity was 2.5 (±0.4) and 1.8 (±0.4) fertile eggs per pair for the first and second attempts respectively. For pairs that remained unchanged through 2006–2007, productivity was consistent between years and breeding attempts. CONCLUSION: Where food and nest sites were not limiting, clutch sizes in north‐east England were similar to those in the native range, and consistent between first and second attempts. This has implications for the future expansion and management of the species. © Crown Copyright 2009. Reproduced with permission of Her Majesty's Stationery Office. Published by John Wiley & Sons, Ltd.  相似文献   

20.
Development duration and reproduction rate of the twospotted spider miteTetranychus urticae Koch (Acarina: Tetranychidae) were studied on five different apple cultivars (‘Amasya’ (local cultivar), ‘Golden Delicious’, ‘Granny Smith’, ‘Starking Delicious’ and ‘Starkrimson Delicious’) at 25°C, 65±10% r.h. and 16:8 L:D. In addition, the same parameters were determined on Golden Delicious leaves at three constant temperatures (20°, 30° and 35°C, 65±10% r.h. and 16:8 L:D) in the laboratory.T. urticae performed better on Granny Smith than on the other cultivars, due mainly to high daily egg production (4.6 eggs/♀/day) and the intrinsic rate of natural increase (r m , which was 0.243 ♀/♀/day). The lowestr m was observed on Amasya variety (0.231 ♀/♀/day). Development periods of immature stages ofT. urticae varied from 6.5 to 15.5 days at 35° and 20°C, respectively, for females, and from 5.9 to 14.5 days at 35° and 20°C, respectively, for males. The development thresholds of the eggs and pre-adult stages, respectively, were 10.78° and 8.43°C, and total effective temperatures were 57.80 and 172.41 degree-days. Mean generation time (T o ) of the population ranged from 9.94 days at 35°C to 25.99 days at 20°C. The net reproduction rate increased from 66.99 ♀/♀ at 20°C to 92.19 ♀/♀ at 25°C, and decreased to 84.34 ♀/♀ at 30°C and to 12.04 ♀/♀ at 35°C. The highest r m occurred at 30°C (0.302 ♀/♀/day) and the lowest at 20°C (0.161 ♀/♀/day). http://www.phytoparasitica.org posting Dec. 19, 2003.  相似文献   

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