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1.
红棕灰夜蛾 Sarcopolia illoba(Butler)是鳞翅目夜蛾科害虫。分布于我国东北、华北、华东、华中及苏联、日本、朝鲜、印度等地。幼虫多食性,为害烟草、甘蓝、马铃薯、甜莱、大豆、豌豆、菜豆等作物。1984年在哈尔滨大豆田中,从该虫幼虫自然死虫体内分离出一株核型多角体病毒。我们对该病毒的形态学进行了观察。这种病毒在国内外尚未见报道。并对12种夜蛾科害虫:迹幽夜蛾(Discestra stigmosa)、甘蓝夜蛾(Mamestra brassicae)、黄地老虎(Scotia segetum)、小地老虎(S.ipsilon)、银纹夜蛾  相似文献   

2.
【目的】Asaia属醋酸菌已被证明与双翅目、膜翅目、半翅目和鳞翅目的多种昆虫存在着重要的共生关系。本研究检测斜纹夜蛾Prodenia litura(Fabricius)、粘虫Mythimna separata Walker、小地老虎Agrotis ypsilon Rottemberg和甘蓝夜蛾Mamestra brassicae Linnaeus体内Asaia的感染情况,并研究了Asaia的传递效率。【方法】基于16 s r DNA特异序列检测,分析Asaia在4种鳞翅目害虫中的感染情况。通过建立感染Asaia的斜纹夜蛾品系,检测其垂直传递效率。【结果】Asaia在斜纹夜蛾、粘虫、小地老虎和甘蓝夜蛾田间种群中均有感染,其感染率分别为45.8%、66.7%、47.2%和31.0%。系统发育分析表明,Asaia 16S r DNA序列可分为3种序列型ST1、ST2和ST3,其中4种昆虫中均含有ST1序列型。父母亲本均感染Asaia的斜纹夜蛾后代,Asaia感染率达到91.7%。【结论】Asaia在鳞翅目害虫中存在较高的感染率,在昆虫物种间可能存在水平传递并且在种内可进行垂直传递。  相似文献   

3.
田间药效试验结果表明,3.2%高效氯氰菊酯·甲氨基阿维菌素苯甲酸盐微乳剂对十字花科蔬菜主要害虫甜菜夜蛾Spodoptera exigua(Hbner)、小菜蛾Plutella xylostella(L.)、菜青虫Pieris rapae(L.)和斜纹夜蛾Spodoptera litura(Fabricius)均具有优良的防治效果,并有较好的速效性和持效性。3.2%高效氯氰菊酯.甲氨基阿维菌素苯甲酸盐微乳剂20,25和30g/667m23个处理药后1d对甜菜夜蛾、小菜蛾、菜青虫和斜纹夜蛾的防治效果为60.67%~77.41%,药后3d的防治效果达81.82%~97.77%,药后7d的防治效果达83.74%~99.25%。3.2%高效氯氰菊酯.甲氨基阿维菌素苯甲酸盐微乳剂可以作为防治蔬菜主要害虫的有效药剂推广使用,推荐使用剂量为25~30g/667m2(12~14.4gai/hm2)。  相似文献   

4.
柑桔潜叶蛾对柑桔的为害及经济阈值的研究   总被引:7,自引:0,他引:7  
调查福州市郊柑桔园柑桔潜叶蛾(Phylocnistiscitrela)在雪柑、芦柑、蕉柑、福桔4个品种上的为害情况.根据其为害特性和柑桔果实产量大小年份可能给经济阈值带来的误差,采用同一树上以秋梢为计量单位,环割被测枝条(避免枝条间养分重新分配而带来误差)的方法,研究了为害秋梢的叶片光合作用强度,当年和翌年春夏梢的生长量,翌年果实品质和重量,以及叶片被害程度与柑桔潜叶蛾幼虫密度的关系.结果表明,柑桔受潜叶蛾为害后具有一定的光合补偿及组织愈伤的补偿能力;根据福州地区1994年柑桔生产力,以雪柑为品种确定经济阈值为1.21头1龄幼虫/嫩叶;缩小了经济阈值受果实产量大小年份差异而带来的误差;同时考虑品种、柑桔园水热条件、产量水平、天敌作用等多种生态因子,建立了多因子经济阈值模型  相似文献   

5.
陈永年 《昆虫知识》2000,37(5):304-305
在湖南 ,春甘蓝的大田生长期一般在 1月下旬至 6月上旬之间 ,这一季节的主要食叶害虫是菜青虫 Pierisrapae L .,其次是灯蛾 ,过去大量发生的小菜蛾近年来一直处于低数量低水平。而甜菜夜蛾、斜纹夜蛾此时发生极少。灯蛾的卵呈块产 ,卵粒裸露 ,单层排列 ,低龄幼虫呈集团性分布 ,不难发现。为此 ,我们只针对主要害虫菜青虫作了虫情简便监测技术的研究。1 方法1 .1 于 1 998年 5月 3日至 6月 4日菜青虫主要发生危害期在甘蓝地及其周边共 0 .0 5 km2的固定范围内每日上午 1 0时计数飞舞的成虫(菜粉蝶 )数 ,一般计数 3~ 5次 ,求其平均值 ;并…  相似文献   

6.
二代玉米螟为害玉米产量损失研究   总被引:1,自引:0,他引:1  
【目的】研究二代亚洲玉米螟Ostrinia furnacalis(Guenee)为害对玉米产量的影响。【方法】以"先玉335"为供试玉米品种,通过人工接虫模拟二代玉米螟不同发生量为害玉米对产量损失的影响。【结果】随着接卵量增加,虫孔数和蛀孔隧道长度增加,玉米单穗粒重降低。单株虫孔数每增加1个,玉米产量损失率增加4.52%;隧道长度每增加10 cm,产量损失率增加8.34%。接卵量与玉米产量损失率的关系符合方程z=-10.0297+4.034 ln(x)。【结论】根据害虫经济阈值的定义,推算出二代玉米螟的防治指标为百株累积卵量12.8块,对二代玉米螟的防治决策具有重要指导作用。  相似文献   

7.
不同温度下的甜菜夜蛾实验种群生命表研究   总被引:19,自引:0,他引:19  
组建了甜菜夜蛾Spodoptera exigua在5种温度下的实验种群生命表。结果表明:在20~32℃,甜菜夜蛾的发育速率随着温度的升高而加快,并符合Logistic模型;甜菜夜蛾卵、幼虫、蛹、产卵前期及世代的发育起点温度分别为13.73℃、15.68℃、15.09℃、12.83℃和15.06℃,有效积温分别为37.9、126.3、73.8、29.2和265.6日·度;甜菜夜蛾在26℃时世代存活率和种群增长指数最高,分别为55.2%和205.9,20℃时不利于种群增长;在26℃和29℃时,甜菜夜蛾的平均产卵量最高,分别为604.7和611.4粒/雌,26℃是甜菜夜蛾最适宜交配的温度,交配率为84.9%,平均精包数为2.46个/雌;高温条件下,甜菜夜蛾的成虫寿命、产卵前期和产卵期均缩短;甜菜夜蛾的世代存活率(S)和种群趋势指数(I)与温度(t)的关系均可用二次抛物线表示:S=-0.5056 t2+27.652 t-326.02 (r=0.91),I=-3.2532t2+178.45 t-2 270.40 (r=0.94)。  相似文献   

8.
两种虫酰肼类新化合物对五种鳞翅目害虫的生物活性   总被引:3,自引:0,他引:3  
为了比较虫酰肼及其衍生物对鳞翅目 5 种害虫的毒力 ,以虫酰肼为对照药剂,分别采用浸叶法、浸虫法和点滴法测定了虫酰肼衍生物 0593 (Ⅲ f) 和 0673 对甜菜夜蛾 Spodoptera exigua(Hübner)、斜纹夜蛾 Prodenia litura (Fabricius)、小菜蛾 Plutella xylostella (Linnaeus)、棉铃虫 Helicoverpa armigera(Hübner)和玉米螟 Ostrinia furnacalis(Guenée)的毒力;通过浸叶法系统研究了虫酰肼和虫酰肼衍生物 0593 对甜菜夜蛾生长发育的影响。结果表明:0593 和 0673 对甜菜夜蛾 4 龄幼虫的触杀毒力分别是虫酰肼的 11.3 倍和 7.4 倍,对斜纹夜蛾 4 龄幼虫触杀毒力分别是虫酰肼的 30.4 倍和 24.7 倍,对小菜蛾 3 龄幼虫浸虫处理的毒力分别是虫酰肼的 4.7 倍和 4.5 倍 ,对棉铃虫3龄幼虫的触杀毒力分别是虫酰肼的 15.5 倍和 15.2 倍,对玉米螟 4 龄幼虫的触杀毒力分别是虫酰肼的 1.3 倍和 2.0 倍,较虫酰肼的毒力都有很大提高,而0593 和 0673 对 5 种害虫的毒力差异不显著。用虫酰肼和 0593 处理甜菜夜蛾 2 龄幼虫,都能导致存活幼虫陆续死亡;化蛹率和正常蛹数降低;成虫羽化率、单雌产卵量和卵的孵化率显著减少,对后代的繁殖力影响显著;在相同处理浓度下,0593 较虫酰肼对甜菜夜蛾后代繁殖力的不利影响更大。因此,0593 是较虫酰肼杀虫毒力更高、对生长发育和繁殖力不利影响更大的药剂,开发应用价值很大。  相似文献   

9.
对防治蔬菜菜夜蛾(S)和斜纹夜蛾(ProdenialituraFabricius)为主并兼治菜螟、菜青虫、小菜蛾等鳞翅目害虫的单五型和复配型苜蓿银纹放蛾核型多角体病毒(AutographacalifornicanuchlearpolyhedrosisVirus,AcMNPV)生物杀虫剂进行筛选。  相似文献   

10.
添加物对Bt制剂杀灭鳞翅目害虫的增效作用   总被引:2,自引:0,他引:2  
以菜青虫幼虫为试虫,经室内毒力测定Bt制剂添加物的增效作用,结果表明11种添加物加入Bt制剂后均有不同的增效作用,将增效添加剂加入Bt8010菌粉,置于54摄氏度恒温条件下贮放14d后,取出测定添加物对Bt8010菌的影响,结果有6种添加物,能明显降低温贮存后Bt8010菌的芽胞数与杀虫率,田间试验结果表明,5种对Bt8010菌安全的增效添加物,按不同比例配成3组复合添加剂,再与Bt8010WP混合后,能明显提高对小菜蛾,菜青虫,甘蓝夜蛾等鳞翅目害虫的杀灭活性。  相似文献   

11.
Green cabbage (Brassica campestris, leafy variety) and turnip (Brassica campestris var. rapifera, rooty variety) were grown in both monocultures and mixtures at three nutrient levels to investigate their responses to nutrient availability with respect to biomass allocation, morphological plasticity and competitive ability. Their allocation parameters and leaf morphological traits were affected by both nutrient availability and developmental stage. Both of the varieties had a smaller biomass allocation to leaf blades, but a greater allocation to petioles at high nutrient levels. Root:shoot ratio (RSR) of green cabbage decreased with increasing nutrient availability, whereas that of turnip increased. Turnip had a smaller leaf blade weight ratio (LBWR) than cabbage, being compensated for by larger leaf area ratio (LAR) and specific leaf area (SLA). Leaf area ratio and SLA of both the varieties increased with increasing nutrient availability as did their mean dry weights. The mean dry weight of turnip was slightly greater than that of green cabbage in their respective monocultures, while that of green cabbage was greater than that of turnip in their 1:1 mixture. Therefore, green cabbage, having inherently greater biomass allocation to leaves, was generally more competitive than turnip with more biomass allocation to roots, especially at higher nutrient levels. However, within a variety, morphological plasticity (variation in LAR and SLA) was more important than the plasticity in biomass allocation (e.g. variation in RSR and LBWR) in determining competitive ability. The implication of our results is that competition models based on biomass allocation pattern alone may fail to predict competitive outcomes and that such models should also take morphological plasticity into full account.  相似文献   

12.
水稻食叶类害虫等量损害系统与复合防治指标   总被引:5,自引:1,他引:4  
陆自强  沈国清 《昆虫学报》1991,34(3):319-325
稻纵卷叶螟Cnaphalocrocis.medinalis Guenèe中华稻蝗Oxya chinensis(Thunberg)稻苞虫Parnara guttatus (Bremer et Grey)是江苏地区水稻的主要食叶类害虫,取食水稻叶片,导致光合叶面积减少.剪叶模拟试验表明,水稻不同生育阶段叶面积损失率与产量损失率呈线性相关.其回归方程分蘖期、孕穗期、腊熟期分别为 D(It)=72.50759It1.15906、D(It)=141.61737It1.08002、D(It)=25.12434It1.00569.在叶面积损失率相同的情况下,产量损失率孕穗期>分蘖期>腊熟期.试验通过三种害虫的各龄取食量,不同生育阶段水稻叶面积及为害与损失率之间的关系,建立了不同生育阶段的经济允许损害水平(EILt).并根据各种害虫的相对潜在取食量,计算了校正等量损害系数,为制订复合防治指标提供了依据.实践证明:以等量损害为单位的复合防治指标有较大的实用价值,生态效益、经济效益、社会效益明显.  相似文献   

13.
Field experiments were conducted from 1972 to 1978 and from 1998 to 1999 to evaluate tobacco budworm, Heliothis virescens (F.) (Lepidoptera: Noctuidae), larval feeding on flue-cured tobacco, Nicotiana tabacum (L.), yield in eastern North Carolina. In the earlier studies, using variety Coker 319, treatment plots were evaluated when either 0 or 100% of plants in a plot were infested with H. virescens larvae. Treatment differences based on actual yield loss (kilograms per hectare) were compared with estimations of yield loss based on leaf consumption and leaf loss. Results indicate actual yield loss when 100% of plants were infested was less than the corresponding estimates of yield loss. In the later experiments, two tobacco budworm-resistant lines, 'CU 263' and 'CU 370', were compared with a commercial susceptible variety, K 326, when 0, 10, 20, or 40% of plants were infested (1998) and 0, 10, 40, 75, or 100% of plants were infested (1999). Although significant increases in leaf equivalents consumed were associated with infestations exceeding the recommended threshold, differences were not detected for yield (kilograms per hectare), quality (dollars per kilogram), and value (dollars per hectare) within each tobacco line. Additionally, there was not a significant correlation between value and infestations level for any of the tobacco lines. These results provide economic support for tolerance of a higher treatment threshold. Although K 326 sustained more leaf equivalent loss than CU 263 and CU 370, the value of K 326 harvested was higher than that of CU 263 and CU 370. To justify use of resistant varieties, the combination of pest pressure and the benefit of host plant resistance must be greater than the capacity of a susceptible variety to produce competitive yields, despite sustaining significantly higher loss.  相似文献   

14.
The lepidopteran pests Plutella xylostella L. (Plutellidae) and Pieris rapae L. (Pieridae: Pierini) are responsible for major yield losses of cabbage, Brassica oleracea L. (Brassicaceae), in North Korea. Preliminary integrated pest management (IPM) programmes using economic thresholds (ETs) to schedule insecticide applications have proved promising and have demonstrated marked increases in yield compared to standard farming practice, which relies heavily on synthetic insecticides. To use ETs effectively on a routine basis, farmers need efficient yet sufficiently precise methods of surveying crops for pests. Here we construct and validate binomial sequential sampling plans for the two-species pest complex and for P. rapae alone. The recommended plans would be practical to implement, demanding maximum sample sizes below 50 plants, and proved very slightly conservative with respect to classifying the population relative to the ET (i.e., they were slightly more likely to suggest control at the ET than not).  相似文献   

15.

There are few evidences on the effect of biochar on vegetable yield, nitrogen (N) and phosphorus (P) leaching losses under intensive vegetable production soil. The current field plot scale study evaluated responses of Chinese cabbage (Brassica oleracea L.) yield, N and P leaching losses using five N treatments of common N application rate according to local farmers’ practice (N100%), reducing 20% or 40% N fertilizer (N80% and N60%), and reducing 40% N fertilizer but incorporating 10 or 20 t/ha biochar (N60% + BC10 and N60% + BC20). Results showed that N80% and N60% decreased both the cabbage economic and leaf yields by 6.8%–36.3% and 27.4%–37.7%, respectively. Incorporation of biochar with reduced N fertilizer rates improved the cabbage yield, in particular the N60% + BC20 matched the yield that observed in N100% treatment. Enhanced N and P uptake capacities of cabbage shoot probably contributed the higher vegetable production under both biochar amendment schemes. Biochar application mitigated the NH4+-N and total P leaching losses by 20%–30% and 29%–32%, respectively, compared with their counterpart treatment N60%. Nevertheless, biochar exerted no influence on the NO3-N leaching. In addition, soil organic matter content was recorded with 7.4%–28.7% higher following 10–20 t/ha biochar application. In conclusion, biochar application can increase economic yield of cabbage via increasing N and P use efficiency, decrease N and P leaching losses, and improve soil quality in an intensive vegetable production system.

  相似文献   

16.
本试验通过利用5个品种蔬菜(萝卜,芥蓝,芥菜,菜芯和白菜)研究萝卜蚜(Lipaphis erysimi)在不同蔬菜上的种群动态以及对寄生于萝卜蚜的菜蚜茧蜂(Diaeretiella rapae)种群的影响。研究结果显示,在30天研究期间,有翅萝卜蚜的平均虫口(蚜虫数/苗)在萝卜、芥蓝、芥菜、菜芯和白菜苗上分别为3.918、0.831、1.149、1.743和5.23头,表明降落在萝卜苗上的有翅蚜数量显著地比在其它蔬菜苗上的高;而无翅萝卜蚜的中均虫口分别为63.421、10.041、24.928、23.323和114.308头,说明萝卜蚜无翅蚜在白菜上的种群显著地高于其它品种蔬菜上的。由于萝卜蚜在不同品种蔬菜上的种群不同,导致菜蚜茧峰种群在不同品种蔬菜上也不同,其僵蚜虫口分别为1.056、0.251、0.277、0.651和1.44头,显示了在萝卜和白菜上的僵蚜数量显著地比其它蔬菜上的高。分析结果表明,萝卜蚜的种群(x)与菜蚜茧峰的种群(y)呈显著的相关关系:y=0.1188+0.0143x(r=0.9739)。本研究还利用试验结果提出了萝卜蚜无翅蚜种群从蔬菜在田间种植后达到防治指标(50头/苗)的临界天数(c  相似文献   

17.
Abstract The population dynamics of alates and apterous of turnip aphid (TA) Lipaphis erysimi (Kalt.) together with the incidence of parasitism by Diaeretiella rapae (M'Intosh) on five host vegetable varieties in the field were evaluated. The results showed that the average populations of TA apterous on host vegetable varieties turnip, Chinese kale, leaf mustard, flowering cabbage and Chinese cabbage were 63. 425, 10. 041, 24. 928, 23. 323 and 114. 308 aphids/plant, respectively. The 'critical day' was used to estimate the date when TA population density on host vegetable varieties reaches its economic threshold. The relationship between TA apterous population ( x ) and mummy aphids parasitized by parasitoid D. rapae was significant, and the regression formula is y = 0. 1211 + 0. 01431 (r=0. 9739**).  相似文献   

18.
研究结果表明:①南美斑潜蝇为害大棚芹菜和芸豆,其虫道面积和产量呈负相关,与产量损失率呈正相关;②曲线回归方程为:Y(大棚芹菜产量)=4.233/(1+0.2669e0.0281X),Y(大棚芸豆产量)=500950.702/(1+39262,76541e^0.0103X),Y(大棚芹菜产量损失率)=68.075/(1+23.1517e^-0.071X),Y(大棚芹菜产量损失率)=71.765/(1+4.26245e^-0.0305X);③经济阈值模型为:X(大棚芹菜)=14.0845ln[23.1575L/(68.075-L)],X(大棚芸豆)=27.3973ln[4.26245L/(71.765-l)]。  相似文献   

19.
在京郊露地生产条件下,研究了控释肥料与速效化肥混配施用对春白菜产量、品质、氨挥发、土壤硝态氮累积和淋失的影响.结果表明:与习惯施肥处理(施N 300 kg·hm-2)相比,控释肥料与普通化肥按纯氮比2∶1混配施用(共施N 150 kg·hm-2)没有造成白菜减产,并显著降低了菜叶中硝酸盐和有机酸含量;与半量施肥处理(施N 150 kg·hm-2)相比,控释肥与化肥混施处理产量和叶片硝酸盐含量无显著差异.控释肥与化肥混施处理提高了白菜氮肥利用率,减少了N3-N淋失量和氨挥发总量.白菜收获后,控释肥与化肥混施处理在20~40、60~80、80~100 cm土层的NO3--N含量显著低于习惯施肥处理.  相似文献   

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