The bionomics ofLiriomyza Trifolii on Gypsophila and Bean Leaves

A study was carried out to determine the distribution of feeding and oviposition punctures made byLiriomyza trifolii Burgess on gypsophila(Gypsophila paniculata ) and bean(Phaseolus vulgaris) leaves, and the development times of the immature stages on these plants. The absolute number of punctures per leaf area was much greater on bean leaves than on gypsophila leaves. The number of mines per leaf was also higher on beans than on gypsophila, but the ratio of mines/punctures was higher on gypsophila. Gypsophila leaves were punctured on both sides, but most of the punctures were on the distal third of the upper leaf side. On beans the punctures were dispersed uniformly on the upper side of the leaf. The larval period (±SE) at temperatures of 20, 25 and 30°C was 9.9±0.2, 4.4±0.1 and 3.7±0.1, and 5.5±O. l, 3.7±0.1 and 2.4±0.1 days, on gypsophila and bean, respectively. The pupal period at 17, 20, 25 and 30°C lasted 19.9±0.2, 14.7±0.1, 10.4±0.1 and 7.8±0.1 days, respectively.     

Effect of gamma radiation on sterility ofliriomyza trifolii flies

The effect of low doses of gamma radiation applied toLiriomyza trifolii Burgess eggs or 1st-instar larvae, on the ensuing flies was studied. Doses of 50 or 40 Gy resulted in very few individuals reaching the adult stage; the life span of these flies was very short and they did not breed. A 25-Gy dose applied at the 1st instar allowed the development of many individuals into adults which emerged successfully, fed, and oviposited viable eggs which completed their development to adults. Contribution from the Agricultural Research Organization. No. 3024-E, 1990 series.     

Effects of a neem-based insecticide on different immature life stages of the leafminerLiriomyza sativae on tomato

The effects of the commercially available neem insecticide NeemAzal-T/S® (neem) (1% azadirachtin) onLiriomyza sativae (Diptera: Agromyzidae) were studied on tomato in Bangkok, Thailand. Neem emulsions were sprayed on the aerial plant parts at five concentrations (from 0.001% to 0.010% a.i.); different aged residues (0, 1, 3, 5, and 7 days) were tested, in both controlled environment rooms and in greenhouses. Irrespective of the residual age of the application, no significant effects on oviposition or egg hatch were detected. However, neem drastically increased larval mortality at the higher concentrations tested. The L1 and L2 larvae were most susceptible. Irrespective of concentration, larval mortality or inhibition of adult eclosion decreased much faster in greenhouses than in controlled environments with artificial light. Nevertheless, our results suggest that neem has potential to controlL. sativae in netted greenhouses.     

三叶斑潜蝇发育起点温度和有效积温的研究

不同恒温条件下测定了三叶斑潜蝇Liriomyza trifolii(Burgess)各虫态的发育历期,并用直线回归法计算出各虫态的发育起点温度和有效积温。结果表明,三叶斑潜蝇的历期、发育速率与温度间相关性明显,其卵、幼虫、蛹及全世代发育起点温度分别为9.20℃、10.80℃、6.43℃、8.40℃,有效积温分别为68.4日度、66.7日度、161.3日度、315.0日度。     

辐照处理纵坑切梢小蠹的初步研究

应用不同剂量的^60Coγ-射线处理纵坑切梢小蠹（Tomicus piniperda Linn）成虫，结果表明，处理剂量为500Gy时，当天死亡率达100％，处理剂量为350Gy时，成虫3d后全部死亡，而以300Gy剂量处理后7d，试虫死亡率亦为100％。处理后30d，200—300Gy剂量的处理未出现卵或幼虫。纵坑切梢小蠹存活和繁殖能力与辐照剂量之间符合剂量效应关系，7d理论致死剂量LD99.99为228．7Gy。     

γ射线辐照对3种杂草种子发芽率的影响初报

本文利用60Co-γ射线对芜菁、猪殃殃和反枝苋3种杂草种子进行了50~1000Gy的辐照处理,研究了不同剂量对3种杂草种子萌发的影响,结果表明,发芽7d后,1kGy以下剂量的辐照对3种杂草种子的发芽具有一定的抑制作用,抑制效果因杂草种类的不同而有差异。     

Effect of Temperature on the Seasonal Incidence of Shootfly,Atherigona naqvii in Wheat at Jaipur,India

Abstract

Seasonal incidence of shootfly, Atherigona naqvii Steyskal was studied in wheat sown on nine dates at approximately fortnightly intervals from 1 October to end of January during the 1973–74 to 1976–77 seasons at Jaipur, India. During the season the pest remained more active from the second fortnight of October to mid-December and again during February and March. These fluctuations appear to have a positive correlation with maximum and minimum temperatures while relative humidity and rainfall did not have any influence. The winter low temperatures during mid-December to mid-February arrested the flies' activity. The crop sown between mid-November and mid-December was found to be almost free from shootfly and no control measures are needed. However, early and late sown crops remained prone to attack.     

冷藏对不同季节采集的美洲斑潜蝇寄生蜂羽化的影响

研究了10％冷藏不同时间对天津地区不同季节采集的美洲斑潜蝇寄生蜂自然种群羽化率和羽化进度的影响。结果表明,不同季节发育的寄生蜂对10℃低温的耐受力不同,不同处理的羽化率和羽化进度有较大差异。7月份和9月中旬的寄生蜂随冷藏时间延长,羽化率显著下降;9月底、11月下旬的寄生蜂耐寒力增强,冷藏15～60d处理后羽化率无显著降低。25℃适宜条件下,7月份、9月底的寄生蜂均在20d内羽化,11月下旬、12月的寄生蜂出现羽化延迟,21～40d之间亦有羽化。9月底的寄生蜂冷藏30、45、60d处理,随冷藏时间延长,16～20d羽化比例明显增加,21～25d依次渐增;11月下旬、12月的寄生蜂冷藏处理后羽化进度加快,冷藏60d内随时间延长,10d内羽化比例明显增加。     

Effects of root- and stolon-infecting fungi on root-colonizing nematodes of white clover

The effects on white clover ( Trifolium repens ) of different combinations of the nematodes Meloidogyne trifoliophila , Helicotylenchus dihystera and Heterodera trifolii and nine stolon-infecting and three root-infecting fungi were studied in a glasshouse experiment. The presence of the fungus Phytophthora megasperma alone increased ( P  < 0·001) root-rot severity and reduced ( P  < 0·001) plant growth. Other species combinations, such as Phoma nebulosa and Alternaria alternata , interacted and increased root-rot severity. Combinations of P. megasperma with Pythium irregulare , and P. nebulosa with Phoma medicaginis or A. alternata , increased M. trifoliophila populations. Several other fungi ( P. irregulare , P. nebulosa , Colletotrichum coccodes , Macrophomina phaseolina , P. medicaginis and Phoma sp.) interacted with the nematode M. trifoliophila causing severe root-knot symptoms. The results indicated that fungi and nematodes interacted to cause root and stolon rot and reduced yields, and that poor persistence of white clover in pastures is likely to be a problem with a complex etiology.     

美洲斑潜蝇空间分布型研究

通过采用聚集度指标的方法,对美洲斑潜蝇在茄子、豆角田空间分布起先了系统研究,测定结果呈聚集分布,为田间调查及防治提供了依据。     

水浸对美洲斑潜蝇存活率的影响

本文研究了水浸对美洲斑潜蝇出叶老熟幼虫及蛹存活率的影响.结果表明,出叶老熟幼虫水浸16h将全部死亡,蛹的不同发育阶段对水的抗逆能力不同.当连续水漫时数长达72h,不同发育阶段蛹的死亡率均达100%.试验结果还表明,每天间断水浸4h,持续4天对蛹的存活率影响不大.若以水浸做为一种压低种群的方法或灭虫措施,则至少需连续水浸3天.     

Oviposition behavior and development of immature stages ofParasierola swirskiana, a parasitoid of the lesser date mothBatrachedra amydraula

Parasierola swirskiana Argaman (Hymenoptera: Bethylidae) is a parasitoid of the mothBatrachedra amydraula Meyrick, a pest of unripe fruits of the date palm,Phoenix dactylifera L. The parasitoid is most commonly found in the field on second-generation host ,larvae. Its biological characteristics were studied in the laboratory. Adult longevity averaged 34.9 and 20.5 days for females and males, respectively. Clutch size ranged between 1 and 13 eggs per host, and was positively correlated with host weight. Females laid an average of 60.4 eggs on 11.6 hosts, with a maximum of 152 eggs on 29 hosts in 53 days. Parasitoids were observed standing motionless upon 52% of the paralyzed hosts, and active brood defense was occasionally observed. Immature development is described. Total development time from egg to adult averaged 13.6 days at 26 ± 2°C and 30-50% r.h. The potential for utilizingP. swirskiana for biological control ofB. amydraula is discussed.     

Studies on morphology and biology of immature stages of the predator Rhyzobius lophanthae Blaisdell (Col.: Coccinellidae)

Morphological characteristics of immature developmental stages of Rhyzobius lophanthae Blaisdell (Col.: Coccinellidae), predator of scale insects of the family Diaspididae (Homoptera), are described. Data about the morphology of eggs, the four larval instars, and the pupa is presented. Larval instars are described in more detail: size of head capsule, length of tibia, distribution of dorsal and lateral setae of abdomen segments for each larval instar is reported. Distribution of spiracles is also given. Study on the biology concerns the influence of prey on the duration of instar periods. The diaspidids Aspidiotus nerii and Aonidiella aurantii were used as food. The mean duration of the developmental period from egg to adult was 27.1 days, and no mortality was observed (0%) when A. nerii was used as prey. The respective numbers when the prey was A. aurantii were 48.8 days and 84%.     

Studies on morphology and biology of immature stages of the predator Rhyzobius lophanthae Blaisdell (Col.: Coccinellidae)

Morphological characteristics of immature developmental stages of Rhyzobius lophanthae Blaisdell (Col.: Coccinellidae), predator of scale insects of the family Diaspididae (Homoptera), are described. Data about the morphology of eggs, the four larval instars, and the pupa is presented. Larval instars are described in more detail: size of head capsule, length of tibia, distribution of dorsal and lateral setae of abdomen segments for each larval instar is reported. Distribution of spiracles is also given. Study on the biology concerns the influence of prey on the duration of instar periods. The diaspidids Aspidiotus nerii and Aonidiella aurantii were used as food. The mean duration of the developmental period from egg to adult was 27.1 days, and no mortality was observed (0%) when A. nerii was used as prey. The respective numbers when the prey was A. aurantii were 48.8 days and 84%.     

紫外线-B辐射增强对葡萄植株形态的影响

在室外自然光的基础上,增加0μW/cm2(CK组)、10.8μW/cm2(T1组)、25.6μW/cm2(T2组)3种紫外线-B(UV-B,280~320 nm)辐射强度,研究UV-B辐射增强对葡萄植株形态的影响。结果表明:(1)对于节间,处理组T1对近生长点的节间有一定的促进作用,但伸长量相对于CK不显著;辐射处理下生成的节间,最终随着辐射量的累积节间长度受到的抑制越显著,且T2>T1>CK。(2)与对照相比,处理组的株高和叶面积都有明显的降低,且T2相似文献   

Effects of flame weeding on weed species at different developmental stages

Field experiments to investigate the efficacy of flame weeding were conducted in southern Sweden on a variety of natural weed flora at different developmental stages. The susceptibility of different species and stages was compared by modelling the dose–response with logistic models. Weed species with unprotected growing points and thin leaves such as Chenopodium album L., Stellaria media (L.) Vill. and Urtica urens L. were susceptible. When these plants had 0-4 true leaves, complete kill was achieved at propane doses of 20-50 kg ha^-1. Species with protected growth points such as Capsella bursapastoris (L.) Medic and Chamomilla suaveolens (P.) Rydb. were tolerant due to regrowth after flaming, and they could be completely killed only in the early stages. Poa annua L. could not be completely killed with a single flame treatment, regardless of developmental stage or propane dose. Plant size had a major influence on the lethal dose requirement. Propane doses of 10-40 kg ha^-1 were required to achieve 95% control of plant numbers for sensitive species with 0-4 true leaves, whilst plants with 4-12 leaves required 40-150 kg ha^-1. When flaming naturally emerged weeds at early developmental stages, split applications of two half-dose treatments 1 week apart did not reduce plant numbers as effectively as a single late flame treatment with the same total dose.     

豌豆潜蝇姬小蜂对美洲斑潜蝇幼虫的产卵寄生和取食寄主行为描述

在实验室条件下,以秒表配合解剖镜的观察方法,比较了豌豆潜蝇姬小蜂Diglyphus isaea对美洲斑潜蝇Liriomyza sativae的产卵寄生和取食寄主的2种寄主处理行为。结果显示：2种处理行为的发生流程存在差异。雌蜂产卵寄生的行为流程为：搜索、刺探、梳理、产卵器插入（产卵）和休息;而雌蜂取食寄主的行为流程为：搜索、刺探、梳理、产卵器插入（不产卵）、取食寄主和休息。雌蜂用于产卵寄生的总处理时间（342.2±33.6s）显著低于用于取食寄主的总处理时间（1327.8±134.2s）;其中2种寄主处理行为中对应的产卵器插入行为时间分别为85.9±7.4s和483.2±43.5s;产卵寄生的雌蜂不取食,而取食寄主的雌蜂的平均单次取食时间为233.8±17.3s。研究结果表明,潜蝇姬小蜂的取食寄主方式属于为非同时发生-致死型。     

美洲斑潜蝇对芸豆、黄瓜的危害损失及经济阈值模型研究

研究结果表明 ,美洲斑潜蝇虫叶率 5%～ 70 %情况下 ,虫叶率与产量损失率之间有明显正相关系 ,其大棚芸豆、露地芸豆和露地黄瓜的直线回归方程式分别为y =3 .58450 0 .0 3 1 65x、y =8.82 943 0 .0 52 0 9x和 y =5.45698 0 .0 652 8x。经济阈值数学模型分别为x=1 1 .962ln( 7.1 94L /( 2 3 .92 9-L) )、x =1 1 .61 1ln( 5.51 66L /( 4 1 .50 3 -L) )和x =0 .71 0 7L /2 .42 3。     

Effect of Bacillus thuringiensis var. kurstaki on survival and mortality of immature and mature stages of Diadegma insulare parasitizing Plutella xylostella

Effects of Bacillus thuringiensis (Bt) on immature stages of Diadegma insulare (Cresson) (Hym., Ichneumonidae) within larvae of diamondback moth (DBM), Plutella xylostella (L.) (Lep., Plutellidae), and on the adult stage as a Bt-honey solution were evaluated at 25?±?1?°C, 65?±?10% r.h. and 16:8?h (L:D) photoperiod. P. xylostella and D. insulare pupae were collected from cabbage fields in Karaj, Iran. A commercial wettable powder formulation of Bt (var. kurstaki, serotype H-3a3b, strain Z-52) was used in these experiments. The value of LC₅₀ for third instar larvae of P. xylostella was 210?ppm. Parasitoid??s adult mortality at field rate of Bt was not significantly different from that of control. Formation of parasitoid??s pupae in Bt-parasitoid combined treatments was significantly lower than parasitoid alone. Formation of parasitoid??s pupae in larvae treated with LC₁₀, LC₃₀ and LC₅₀ of Bt and then exposed to parasitoids after 48?h was 5%, 3% and 2%, respectively, which was significantly lower than that of the parasitoid alone (41%). Mean percentage mortality of larvae of DBM in LC₃₀ and LC₅₀ concentrations of Bt combined with the parasitoid was approximately 100%. Our results showed that B. thuringiensis kills D. insulare larvae indirectly by killing susceptible hosts in which they are developing. Successful use of multiple biological control agents will depend on close monitoring of their compatibility in the field. Our results could be useful in this purpose.     

南美斑潜蝇成虫对不同颜色粘卡的趋性及日活动规律研究

本试验使用８种不同颜色的粘性色卡对南美潜蝇成虫的趋性进行试验。结果显示柠檬黄和桔黄卡对成虫的诱集效果较好。夏天在三种天气下粘卡监测成虫的结果表明,晴天和阴天成虫有有两个活动高峰,分别是７：００－１０：００和１３：００－１７：３０,雨天成虫较少活动,全天无明显活动高峰。