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1.
菜蚜二项式抽样设计及其精度分析   总被引:2,自引:0,他引:2  
1990~1992年间对杭州市郊区青菜上桃蚜(Myzuspersicae)、萝卜蚜(Lipaphiserysimi)及其混合种群的田间近100组调查数据,利用每样方(株)虫口不超过数阈值T(分别为0、1、5、10、20、30、40)头蚜虫的植株比例(PT)与种群密度(m,头·株-1)的关系,通过拟合经验公式ln(m)=a+bln[-ln(PT)]而设计的二项式抽样.通过对三者不同数阈值(T)的回归决定系数(r2)、种群密度的回归估计方差(Var(m))、抽样精度(以d表示)和实际应用等的比较,结果表明当桃蚜种群处于较高密度即m≥10时,其理想的T值为30;当萝卜蚜种群处于较高密度即m≥5时,其理想的T值为10;而它们的混合种群未得到其理想的T值.数阈值T为30和10可分别用于桃蚜和萝卜蚜的二项式抽样设计.而传统的二项式抽样即0~1抽样由于应用于小白菜上菜蚜的抽样设计时产生很大的误差,不宜采用.  相似文献   

2.
萝卜蚜不同虫口密度下的二项式抽样设计   总被引:1,自引:0,他引:1  
基于1990—1992年间对杭州市郊区小白菜上萝卜蚜(Lipaphiserysimi)种群的田间抽样调查数据,根据虫口密度(m),将数据归为两组,一组为整个虫口密度范围的数据;另一组为虫口密度≤5头/株范围的数据.每组数据选择不同的数阈值(T),利用每样方不超过T头蚜虫的植株比例(P_T)与种群密度的关系,通过拟合经验公式Ln进行二项式抽样设计.对抽样方差(用MSE估计)、抽样精度(用d估计)进行分析发现,当用整个密度范围的数据进行拟合,且种群处于较高密度(m≥5)时,其理想的T值为10,可用于小白菜上萝卜蚜种群的二项式抽样设计.当用虫口密度m≤5的数据进行拟合时,T=4时可保证抽样精度,但从实际应用考虑,则不宜用于萝卜蚜的二项式抽样设计.应用本文方法所发展的0—1抽样方法,无论是在整个密度范围还是在密度≤5的范围,都由于产生较大的抽样误差而不宜用于萝卜蚜。  相似文献   

3.
为了明确菜蚜茧蜂对萝卜蚜的控制作用,本文研究了在云南玉溪以6个不同蚜蜂比释放菜蚜茧蜂对萝卜蚜的寄生率,结果表明,按6个不同蚜蜂比释放菜蚜茧蜂寄生萝卜蚜后,其对萝卜蚜的寄生率随时间变化的曲线相似。放蜂后第3天,其对萝卜蚜的寄生率即达4%左右。前12 d寄生率虽有波动,但寄生率较低,多在5%以下,之后寄生率开始逐渐上升。蚜虫数量越多,其寄生率反而越高,21 d时,蚜蜂比250∶1和500∶1的寄生率已达26.06%和24.23%,显著高于其它蚜蜂比。蚜蜂比5∶1和25∶1时,萝卜蚜数量的增长最慢,21 d时,其数量仍呈直线上升趋势。蚜蜂比50∶1和150∶1时,萝卜蚜数量的增长开始呈直线上升趋势,到第18天趋于平稳。而蚜蜂比250∶1和500∶1时,萝卜蚜在第9天后,其种群数量呈爆发式增长,到第15天时即趋于平稳。萝卜蚜数量与有翅蚜数呈线性关系y=0.0097 x+10.953。僵蚜数与有翅蚜数呈指数函数模型,y=9.2582e0.0017 x。本研究表明菜蚜茧蜂对萝卜蚜有一定的控制作用,可以作为生物防治萝卜蚜的选择之一。  相似文献   

4.
<正> 蚜虫是蔬菜的大敌,它不仅影响蔬菜的产量和品质,而且是白菜、番茄、马铃薯、榨菜等多种蔬菜病毒的主要传播媒介。目前为害蔬菜的蚜虫有棉蚜、萝卜蚜(菜缢管蚜)、桃蚜和甘蓝蚜等。 蚜虫,特别是有翅成蚜,在迁飞中,喜欢黄色、草绿色,而厌恶银灰色和白色。针对这种习 蚜虫是蔬菜的大敌,它不仅影响蔬菜的产量和品质,而且是白菜、番茄、马铃薯、榨菜等多种蔬菜病毒的主要传播媒介。目前为害蔬菜的蚜虫有棉蚜、萝卜蚜(菜缢管蚜)、桃蚜和甘蓝蚜等。 蚜虫,特别是有翅成蚜,在迁飞中,喜欢黄色、草绿色,而厌恶银灰色和白色。针对这种习  相似文献   

5.
烟蚜茧蜂随寄主有翅桃蚜迁飞而被携带扩散的模拟实验   总被引:1,自引:0,他引:1  
郭近  冯明光  陈学新 《昆虫学报》2010,53(2):175-182
蚜虫寄生蜂的广泛分布可能与有翅蚜的迁飞有关。为了证明这一假说, 本研究利用微小昆虫飞行磨系统, 分数十批(≤16头/批)对被烟蚜茧蜂Aphidius gifuensis Ashmead单头寄生后的有翅桃蚜Myzus persicae (Sulzer)进行模拟飞行并系统观察了飞行后有翅桃蚜的单头定殖情况。对实验观察数据按飞行时间和飞行距离进行归类, 采用单因素方差分析方法分析飞行时间和飞行距离对有翅桃蚜定殖后的存活和生殖力、烟蚜茧蜂发育等变量的影响; 采用多项式回归分析对所有变量和归类的数据进行统计和分析。结果表明: 成功飞行并定殖的有翅桃蚜有378头, 其中239头有翅桃蚜定殖后形成僵蚜。形成僵蚜的有翅桃蚜在飞行实验时平均飞行时间和飞行距离分别为2.63 h和2.16 km, 定殖后平均存活了6.11 d, 定殖第6天和第14天平均产若蚜累计数量分别为8.5头和162头。形成僵蚜和未形成僵蚜的有翅蚜的模拟飞行数据和定殖观察数据无显著差异。形成僵蚜的239头有翅桃蚜中, 最终成功育出烟蚜茧蜂205头, 僵蚜出蜂率为85.8%。雌雄性比为1∶5.2。结论认为, 专性寄生蚜虫的烟蚜茧蜂可以利用有翅蚜的迁飞而被携带扩散传播, 有翅蚜迁飞在蚜虫寄生蜂扩散中具有重要作用。  相似文献   

6.
杭州郊区菜蚜种群的数量消长规律   总被引:10,自引:3,他引:7  
对杭州郊区菜蚜的数量消长规律进行了连续多年的系统调查 .结果表明 ,在杭州郊区十字花科蔬菜上发生的菜蚜只有桃蚜 (Myzuspersicae)和萝卜蚜 (Lipaphiserysimi) .2种菜蚜混生种群的数量消长 1年中有 2个明显的高峰 ,分别出现在 5~ 6月和 1 1月前后 ;一般年份高峰期田间虫量可达平均每株 50 0头以上 ,且第 2个高峰虫量较高 ,持续时间较长 .在夏末秋初气温明显偏低的年份 ,8~ 9月作物上虫量上升迅速 ,最高也可达平均每株上千头的水平 .盛夏和隆冬季节数量都很低 .每年的 1 2月至次年的 5月以桃蚜占绝对优势 ,7~ 1 0月以萝卜蚜占绝对优势 ,而 5~ 7月和 1 0~ 1 2月则 2种蚜虫的发生比例交错变换 .温度是决定菜蚜混生种群数量消长规律和导致 2种蚜虫季节消长规律差异的一个主要因子 .文中对食料、天敌等因子的作用也做了讨论 .  相似文献   

7.
利用灯光控制害虫是蔬菜绿色防控的重要手段之一。本文以黄瓜为供试材料,研究蓝光照射对设施黄瓜蚜虫种群数量的影响。结果表明,蓝光照射对设施黄瓜上有翅蚜和无翅蚜均有较强的驱避作用,蓝光照射2 d后,有翅蚜和无翅蚜种群数量分别下降了65.91%和45.26%,校正虫口减退率分别达到了54.22%和52.83%。随着照射时间的延长,蚜虫种群数量持续下降,校正虫口减退率不断上升,照射14 d后,有翅蚜和无翅蚜种群数量分别下降了78.18%和96.40%,校正虫口减退率分别达到了76.67%和96.40%。蓝光照射可以增加黄板对蚜虫的诱集虫量,蓝光照射3 d后,处理区黄板上蚜虫的数量较对照区黄板增加65.08%。研究发现,蓝光照射对黄瓜蚜虫具有直接的驱避作用,同时还可以增加黄板对蚜虫诱集作用。  相似文献   

8.
载体植物系统是近年发展的新型生物防治技术。本文以桃蚜Myzus persicae Sulzer、甘蓝蚜Brevicoryne brassicae(Linnaeus)和蚕豆蚜Aphis craccivora为候选替代寄主,烟草、玉米、生菜、甘蓝、蚕豆和菜薹为候选载体植物,确定了菜蚜茧蜂的替代寄主为桃蚜,载体植物为烟草。在确定了合适的蜂(♀)蚜比(1∶100)后,以起始桃蚜量2000头/株构建了载体植物系统。该系统28 d内共产生2770头僵蚜,羽化率为83.33%。在菜蚜为100头的菜薹上接入1头由载体植物系统繁殖所得的雌性菜蚜茧蜂,任其自由寄生24 h后移出,其对目标害虫菜蚜的寄生率达到71.17%。在温室1 m×1 m×1 m的白色网笼中放置菜薹植株15盆,分别向每株菜薹上接入菜蚜20头,自由繁殖15 d后置入1株菜蚜茧蜂载体植物系统,其后7 d和14 d的菜蚜减退率分别为83.11%和95.80%。这说明菜蚜茧蜂载体植物系统能产生大量菜蚜茧蜂,并且在温室中能成功地控制菜蚜危害。  相似文献   

9.
本是作对山东省中南部地区蚜茧蜂种类调查的结果.共鉴定出12属25种.其中新种1种。山东省新记录种17种.72%的种类为农作物.林果上蚜虫的寄生蜂;有些种类发生量大,对蚜虫抑制作用显.如乌兹别克蚜茧蜂、烟蚜茧蜂、菜蚜茧蜂等.调查记录了获得的蚜茧蜂种类,寄主及分布,并对新种作了描记.  相似文献   

10.
作者通过田间调查和室内接种观察,22种早春寄主上的蚜虫经鉴定有16个种,其中5个优势种。在棉苗上强迫接种均能生存,但只有14种寄主上的蚜虫能在棉苗上繁殖后代。四川早春气温回升快,蚜虫和蚜茧蜂均出现早。棉田周围5种早春寄主上的蚜茧蜂强迫接种能寄生棉蚜。油菜、大白菜上蚜茧蜂寄生棉蚜的寄生率高达80%以上,说明早春寄主上的蚜茧蜂与大田宿主有相互转移关系。  相似文献   

11.
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   

12.
Host selection, development, survival, and reproduction of the turnip aphid, Lipaphis erysimi (Kaltenbach), on selected green and red cabbage varieties, Brassicae oleracea L. variety capitata, were studied in the laboratory. Although numbers of alate L. erysimi on different varieties varied generally, more alate adults and nymphs were observed on green than on red varieties on day 3; whereas, these differences were not so significant on day 15. There were no significant differences in alate adults on all six varieties on day 15. Numbers of nymphs and apterous adults of L. erysimi varied among the varieties. When mean numbers of those aphids on green varieties were compared with those on red varieties, the green varieties had more nymphs and apterous adults than those on the red varieties. Developmental durations of L. erysimi nymphs also varied among all varieties, and the nymphs fed on green varieties developed longer than those fed on red varieties. Adult longevities on these cabbage varieties were not significantly different; whereas, the adult fecundities were. Survival rates of L. erysimi varied greatly among all varieties, but there are no significant differences between the green and red varieties. Factors that might affect aphid host selection, growth, longevity, fecundity, and survivorship were discussed.  相似文献   

13.
The poplar petiole gall aphid, Pemphigus populitransversus Riley, has been one of the major pests on cruciferous vegetable in the Rio Grande Valley (LRGV) of Texas since the late 1940s. It normally migrates from poplar trees to cruciferous vegetables in the fall, and migrates back to the trees in early spring of the coming year. Some root‐feeding aphids were found on cruciferous vegetables in late spring and early summer in 1998 and the following years. Those aphids have been identified as Pemphigus obesinymphae Moran. This discovery completely changed the current knowledge about the root‐feeding aphids on cruciferous vegetables in the LRGV. Due to their small size, morphological and feeding similarities between P. populitransversus and P. obesinymphae, their identification and distinction are difficult. In this study, random amplification of polymorphic DNA (RAPD) and amplified fragment length polymorphism (AFLP) were used to distinguish these two species over a period of time when the two species occurred together, or separately, in cabbage fields. The two species occurred on cabbage at different times of the year, and overlapped from October to June. From May to October, both species migrated to their primary hosts. The apterous aphids found on cabbage in winter contained mainly P. obesinymphae, whereas in early spring more apterous P. populitransversus were recovered. The root‐feeding aphids would feed on cabbage plants as long as this host was available even during the hot, dry summer in the LRGV, although their populations were generally low. Both RAPD and AFLP techniques were efficient in discriminating the two species that showed obviously genetic variability. These molecular techniques confirmed the existence of the two aphid species in apterous samples collected from the soil in cabbage fields in the LRGV, and the results performed by RAPD were confirmed by AFLP. Furthermore, the results suggest that RAPD technique was a better choice despite its reproducibility problem, as it was less time‐consuming and required less technology, labor and expense than AFLP.  相似文献   

14.
将高纯度球孢白僵菌分生孢子粉兑入一种含悬浮稳定剂及紫外保护剂的矿物油中,配成含孢量为100亿/ml的孢子悬乳剂(纯菌剂),再添加3%的吡虫啉10%可湿剂而得菌药混配剂,于2003年5月在浙江余姚进行了防治蔬菜蚜虫的田间药效试验和农户示范。在两块夏熟白菜地中,纯菌剂和菌药混配剂均用1000倍稀释液(107个孢子/ml)常规喷雾2次,并设清水对照和低用量吡虫啉对照。结果表明,混配剂在两块菜地的相对防效分别达94.5%和86.2%,纯菌剂分别达86.4%和73.1%,而低用量吡虫啉处理的最高防效仅为50%左右。在入夏豇豆、甘蓝、白菜、萝卜及梨树上用菌药混配剂1000倍稀释液对多种蚜虫进行的农户示范试验中,一次性喷雾后5~10d内对菜蚜防效为48%~68%,尤对梨二叉蚜的防效高达99%。在对含有和不含添加剂的两配方孢子悬乳剂进行的常温避光18个月贮存中,活孢率在头7个月均稳定在95%左右且未受配方影响,第10个月活孢率仍有75%左右。而后,含添加剂配方的活孢率下降加速,至16个月时基本失活;而不含添加剂配方的活孢率在第16、17及18个月时还有57%、51%和42%。  相似文献   

15.
The yellowmargined leaf beetle, Microtheca ochroloma St?l (Coleoptera: Chrysomelidae), is an introduced pest of cruciferous crops in the southern United States, and arguably the most damaging pest of organic crucifer vegetable production in the region. Studies were conducted in the greenhouse and laboratory to investigate host finding and acceptance preference of M. ochroloma on four commonly grown cruciferous crops: cabbage (Brassica oleracea L. variety capitata), collards (B. oleracea L. variety acephala), napa cabbage [B. pekinensis (Lour.)], and turnip (B. rapa L.) First, adult beetles were allowed to choose among the four plants in a multiple-choice greenhouse cage experiment and host preference was evaluated by using three parameters: number of beetles on each plant, number of larvae on each plant, and plant damage ratings. The results showed that M. ochroloma adults actively discriminated among the four host plants, with significantly higher numbers recorded on turnip and napa cabbage than on cabbage or collards. Significantly higher numbers of larvae also were recorded on turnip and napa cabbage starting on day 10. Similarly, higher damage ratings were recorded on turnip and napa cabbage than on the remaining two hosts. Results of four-choice olfactometer experiments, which compared attraction of M. ochroloma to headspace volatiles of the four host plants, demonstrated that host preference is mediated primarily by plant volatiles. Both sexes were significantly more attracted to napa cabbage than to the remaining treatments, with turnip being the second most attractive plant. These results confirm that turnip and napa cabbage are two preferred host plants of M. ochroloma, and may support the development of a trap crop system and attractant-based strategies for managing M. ochroloma in crucifer production.  相似文献   

16.
《Journal of Asia》2002,5(2):185-191
The vertical and temporal distribution of an aphid, Aphis gossypii Glover, and the coccinellid populations on six chilli varieties were studied. The total number of apterous aphid per plant stratum was significantly different among plant strata of a particular variety (treatment) as well as among the treatments. Generally, the total number of aphids was significantly greater in the lower stratum than in the middle and upper strata. However, the varieties with erect and open plant architecture (Kulai and MC 11) had significantly less number of apterous aphids at all strata as compared to varieties with compact or prostrate plant architectures. There was a significant difference in the total number of coccinellids per plant strata among the treatments but not within a treatment. The distribution of apterous aphid populations varied significantly among sampling periods and treatments. The temporal distribution of coccinellids showed a similar trend as that of apterous aphids. The total number of alate aphids caught per week was significantly different among the sampling periods. However, its population was significantly greater during the early season and gradually declined as the season progressed except during June 18 to 24. The importance of recording the most observed coccinellids species, which limit the aphid populations at each particular plant stratum per variety, and the conditions that favor natural enemies are also discussed.  相似文献   

17.
Pieris rapae curucivora Boisduval is a major cause of damage to important Brassicaceae vegetable crops. The method of host landing plant selection by adult females was investigated by covering cabbage (host) and lettuce (non-host) plants to block visual and/or olfactory signals, and also by using volatile extracts of both plants.  相似文献   

18.
南美斑潜蝇寄主选择性与植物次生化合物及叶毛的关系   总被引:11,自引:0,他引:11  
采用非自由选择法,以刺伤孔(包括取食孔和产卵孔)数为指标,在室内测定了南美斑潜蝇对6科、16种、22个蔬菜品种的寄主选择性。结果表明,南美斑潜蝇对供试蔬菜品种的选择性存在显著差异,选择性大小依次为豆科>菊科>葫芦科>茄科>伞形科>十字花科; 菜豆和茼蒿是南美斑潜蝇最喜欢产卵和取食的寄主,而甘蓝和番茄是其选择性最差的寄主。化学分析和解剖镜观察表明,叶片单宁酸、黄酮含量及叶毛密度在供试品种间存在显著差异: 苦瓜的单宁酸含量最高,其次为豌豆、番茄和青椒,含量最低的为金丝搅瓜、茼蒿、菜豆和美国西芹; 黄酮含量最高的为甘蓝和番茄,其次为苦瓜,最低为茼蒿、菜豆和美国西芹; 南瓜和小白菜的叶毛密度最高,其次为西葫芦、金丝搅瓜和甘蓝,最低为青椒、莴苣和苦瓜。相关分析表明,南美斑潜蝇寄主选择性与叶片单宁酸和黄酮含量呈显著的负相关关系,相关系数分别为-0.4425( P=0.0392)和 -0.5728( P=0.0053),而与叶毛密度相关关系不显著( R=-0.1807,P=0.4211)。说明黄酮和单宁酸对南美斑潜蝇产卵和取食具有明显的抑制作用。  相似文献   

19.
棉花型和瓜型棉蚜产生有性世代能力的分化   总被引:2,自引:0,他引:2  
高雪  刘向东 《昆虫学报》2008,51(1):40-45
为了明确寄主专化性是否会影响棉蚜的繁殖策略或生活史对策,采用低温和短光照组合(18℃,L∶D=8∶16)分别对棉花型和瓜型棉蚜进行有性世代的诱导,比较两寄主专化型棉蚜产生有翅蚜、雄性母、雌性母及无翅孤雌蚜的能力。结果表明:两寄主专化型棉蚜在产生有性世代能力上存在显著差异,表现为棉花型棉蚜在诱导后代中产生有翅蚜、雄性母和雌性母的比率显著高于瓜型棉蚜,并且雌、雄性母产生的时间明显早于瓜型棉蚜。瓜型棉蚜在诱导条件下产生无翅孤雌蚜的比率显著高于棉花型棉蚜,并且发现有不产生有性世代的营专性孤雌生殖个体,而在棉花型棉蚜中没有发现。产生性母蚜的棉花型和瓜型棉蚜均可同时产生孤雌胎生后代。寄主型与诱导时间长短对棉蚜有性世代的产生存在交互作用。采集于田间棉花和黄瓜上的棉蚜,也表现为棉花上的易产生有性世代,在诱导的第2代中产生性母蚜的比率显著高于黄瓜上的棉蚜,并且性母蚜比率在诱导的第2代与第3代间无显著差异; 但黄瓜上的棉蚜性母蚜产生比率第3代显著高于第2代。由此推测,棉蚜寄主专化性的形成与生活史特性的分化有关。  相似文献   

20.
Knowledge of the vertical and horizontal distribution of Aphis gossypii Glover (Hemiptera: Aphididae) on genetically modified cotton plants over time could help optimize decision-making in integrated cotton aphid management programs. Therefore, the aim of the present study was to determine the vertical and horizontal distribution of A. gossypii in non-transgenic Bt cotton and transgenic Bt-cotton over time during two cotton seasons by examining plants throughout the seasons. There was no significant interaction between years and cotton cultivar treatments for apterous or alate aphids. Considering year-to-year data, analyses on season-long averages of apterous or alate aphids showed that aphid densities per plant did not differ among years. The number of apterous aphids found per plant for the Bt transgenic cultivar (2427 apterous aphids per plant) was lower than for its isoline (3335 apterous aphids per plant). The number of alate aphids found per plant on the Bt transgenic cultivar (12.28 alate aphids per plant) was lower than for the isoline (140.56 alate aphids per plant). With regard to the vertical distribution of apterous aphids or alate aphids, there were interactions between cotton cultivar, plant age and plant region. We conclude that in comparison to non-Bt cotton (DP 4049), Bt cotton (DP 404 BG (Bollgard)) has significant effects on the vertical, horizontal, spatial and temporal distribution patterns of A. gossypii, showing changes in its distribution behaviour inside the plant as the cotton crop develops. The results of our study are relevant for understanding the vertical and horizontal distribution of A. gossypii on Bt cotton cultivar (DP 404 BG (Bollgard)) and on its isoline (DP 4049), and could be useful in decision-making, implementing controls and determining the timing of population peaks of this insect.  相似文献   

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