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1.
首次发现我国柑橘小实蝇沃尔巴克氏体的共生   总被引:2,自引:0,他引:2  
沃尔巴氏体(Wolbachia)是广泛分布于节肢动物体内的一类共生细菌,它们可以调控宿主的生殖活动.本研究利用沃尔巴克氏体wsp基因的一对通用引物(81F,691R),成功地从我国柑橘小实蝇雄成虫的总DNA中扩增到一段400bp左右的wsp基因片段,通过wsp基因的特异性扩增首次证实了沃尔巴克氏体在我国柑橘小实蝇雄虫体内的共生.  相似文献   

2.
Clubroot disease, caused by Plasmodiophora brassicae, has become a major problem in the production of cruciferous crops worldwide. In this study, a population of 121 doubled haploid (DH) lines derived from a crossing between a resistant and a susceptible canola (Brassica napus) genotype was subjected to phenotypic and genotypic studies to determine the inheritance and location of the resistance gene(s). After inoculation with pathotype 3 of P. brassicae, the lines showed a 1:1 segregation ratio for resistance, indicating that resistance in this population is controlled by a single gene. Fifteen PCR‐based markers that were known to be linked to clubroot resistance (CR) genes were screened against genomic DNA from parents and resistant and susceptible bulks. Marker GC1680, linked to the CR gene CRa, exhibited polymorphism between the parents and between the resistant and susceptible bulks. CRa target primers were used to amplify fragments from the two parents and the resultant sequences were compared. A high degree of sequence similarity was found between the parents in the nucleotide binding site domain of CRa. In contrast, sequence polymorphisms were detected in the leucine‐rich repeat (LRR) domain. One pair of primers that amplify a band from the LRR region of the resistant parent but not the susceptible parent was used to screen the DH population. Amplicons were obtained from 60 of the 61 resistant lines and two of the 60 susceptible lines; thus, three recombinants were found. Based on these results, a resistance locus linked to CRa was found.  相似文献   

3.
龚秀泽  陈武恒 《植物检疫》2007,21(3):139-141
截获泰国产芒果中的果核杧果象,在我国气候环境下对该虫的幼虫和蛹饲养、成虫越冬存活率及浸水死亡率等进行研究.该虫在原芒果果核内饲养的幼虫出成虫存活率为59.1%,蛹为75%;在恒温湿条件下保湿饲养的幼虫出成虫存活率为27.3%,蛹为36.3%.成虫恒温湿条件下不同材料中越冬存活率均达66%以上,常温湿条件下平均不足49%.越冬前成虫浸水10h全部死亡,常温湿条件下越冬后成虫浸水6h全部死亡,恒温恒湿条件下越冬后成虫浸水8h全部死亡.研究结果表明,泰国产的果核杧果象在我国南方环境条件中化蛹、羽化、越冬仍然存在较高的存活率,该虫可以在我国南方芒果产区定殖危害.  相似文献   

4.
多效唑在油菜生产上的应用效果   总被引:5,自引:0,他引:5  
刘金泉  王静  邹华 《江西植保》2004,27(4):187-187
培育壮苗是目前油菜生产上提高产量的关键措施之一,植物生长调节剂多效唑对油菜壮苗有一定的促进作用。笔者探讨不同浓度多效唑对培育油菜壮苗及其产量的影响,旨在为多效唑在油菜上应用提供依据。  相似文献   

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6.
Thirty-nine field populations of Frankliniella occidentalis (Pergande) were collected from different crops (sweet pepper, tomato, lettuce, artichoke, melon, cucumber, carnation, broad bean, peach and plum) in Murcia (south-east Spain). All populations were reared separately in the laboratory to obtain enough individuals for bioassays. Female thrips were bioassayed, using a standard topical application method, against methiocarb, methamidophos, acrinathrin, endosulfan, deltamethrin and formetanate. Methiocarb was the only insecticide that showed a high efficacy against F occidentalis at field dose rates. Acrinathrin and methamidophos were moderately effective, while endosulfan and deltamethrin were ineffective. Only moderate levels of resistance (Resistance Ratios at LC50 of 10-30) were detected for the selective insecticides methiocarb, formetanate and acrinathrin used against F occidentalis in crops where these insecticides are used intensively. This generalized and low level of resistance to these insecticides, coupled with a lack of efficacy for the three broad-spectrum insecticides, was observed even in intensively managed vegetable crops. Implementation of IPM strategies in Murcia has contributed to more successful insecticide anti-resistance management.  相似文献   

7.
Aeciospores in Uromyces fabae were found to be repeating spores and play an important role in pea rust outbreaks in the North Eastern Plain Zone (NEPZ) of India. Experiments conducted on pea rust from 2001 to 2004 revealed the dominance of aeciospores at all growth stages of pea in this region. Urediospore production was erratic and was only observed in a few samples of stems and tendrils (5–10%). Inoculation of pea plants either by aeciospores or urediospores resulted in the production of aeciospores. Production of aeciospores was observed at a temperature range of 10–25 °C, with a maximum at 25 ± 2 °C. Among the different growth stages of pea, the pod formation stage was highly susceptible and produced the maximum number (744) of aecidia/leaf at 20–25 °C. Significant effects of growth stages and temperature were also noticed for pustule number. Urediospore production mainly coincided with the senescence of the pea plants. Maximum germination (2%) of aeciospores was observed at 25 °C, whereas maximum urediospore germination (3.5%) was at 15 °C. Temperatures > 15 °C decreased urediospore germination. A relative humidity (RH) of 100% was favourable for aeciospore germination while 98% RH favoured urediospore germination. Typical histo-pathological behaviour of the aeciospores was observed.  相似文献   

8.
9.
Tephritid parasitoids reared from 26 different host fruit species showed remarkably little diversity across 21 Brazilian counties. The majority of the parasitoids (81.4%) belonged to the braconid subfamily Opiinae, with Doryctobracon areolatus (Szépligeti) the most commonly encountered species. Four other opiines, namely D. brasiliensis (Szépligeti), Opius bellus Gahan, Optus sp. and Utetes (Bracanastrepha) anastrephae (Viereck) were also reared, but in much smaller numbers. Asobara anastrephae (Muesebeck), an alysiine braconid parasitoid of tephritids, accounted for an additional 18–6% of the individuals reared from tephritids. The hosts and distribution patterns of the braconid parasitoids of Brazilian fruit‐infesting Tephritidae are summarized.  相似文献   

10.
11.
Pheromone traps were placed in the market place in Banja Luka, and in greenhouses and open field tomato crops, on 13 September 2010 to determine the presence of Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae) in Banja Luka region. Based on examination of traps, the presence of T. absoluta was confirmed for the first time in the Republic of Srpska. Only mines of Liriomyza species were found by examining leaves under a stereomicroscope. In 2011, pheromone traps were placed in greenhouses at several locations (Banja Luka, Prijedor, Novi Grad, Kozarska Dubica, Ljubinje and Trebinje) at the beginning of June, and in open fields in Bijeljina and Trebinje at the beginning of September. Examination of the traps was carried out at intervals of 15 days. A sample of 100 leaves, taken from 20 randomly selected plants, was examined in order to evaluate the intensity of the attack. The first adults were caught in greenhouses in Ljubinje and Trebinje on 18 June 2011; in open field crops in Bijeljina on 9 September 2011 and in Banja Luka on 5 October 2011. Adults were not captured in Prijedor, Novi Grad or Kozarska Dubica, and no mined leaves were observed. The intensity of attack was evaluated on the basis of active infestation (percentage of leaves with active mines compared with all mined leaves). The strongest intensity of active infestation was recorded in the open field crops in Trebinje, where 19% of leaves with active mines were found.  相似文献   

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13.
Weeds that emerge along with or immediately after crop plants usually can reduce the yield of those crops. Two randomized complete block design experiments were conducted during 2006 and 2007 in Tabriz, Iran to determine the critical period of redroot pigweed control in the green bean hybrid “Cantander”. The treatments were weed‐infested and weed‐free plots at 2, 4, 6, 8, 10, and 14 weeks after bean emergence (WABE). The green bean biomass was affected by the early emergence of redroot pigweed, but it was not reduced when redroot pigweed emerged at 10 weeks after crop emergence, along with crop emergence, and grew with green bean until 4 WABE. The redroot pigweed biomass decreased by 2.7 g m?2 per day when weed emergence was delayed. Each 100 g m?2 of weed biomass that was produced resulted in a 1.4 kg ha?1 loss in the green bean yield. When redroot pigweed interference lasted for ≥4 weeks after green bean emergence, the green bean yield was reduced significantly. Weeds, which emerged 2 weeks after green bean and thereafter were controlled, did not decrease crop productivity significantly. The highest crop yield was obtained when the weed emerged at 14 WABE. The critical period of redroot pigweed control, considering a 10% yield loss, was between 19 and 55 days after green bean emergence. Thus, weed control practises should be begun no later than 3 WABE and should continue until at least 8 WABE in order to obtain the maximum green bean yield.  相似文献   

14.
An analysis is presented of a community of mesostigmatid mites from the nests of Clethrionomys glareolus found in the forest biotopes of Vsetínské Beskydy Mts. (North Moravia) throughout all seasons of the year. Main attention was paid to the structure of the nest community, relationships of mites to their host and interspecific relationships in the mites themselves. Primarily cluster and factor analyses based on correlation matrix were used for mathematical assessment. The particular elements of correlation matrix were Spearman's non-parametric correlation coefficients computed from frequencies of species in the nests studied.  相似文献   

15.
The developmental biology of Mallada desjardinsi (Navas) and Chrysoperla congrua (Walker) on the American bollworm, Helicoverpa armigera and the cotton aphid, Aphis gossypii was studied in the laboratory at 28–32°C. Total larva! periods of M. desjardinsi and C. congrua on H. armigera eggs were 14.4 and 14.8 days respectively. However, when reared on A. gossypii larval periods of M. desjardinsi and C. congrua were 14.9 and 13.5 days respectively. When reared on H. armigera 52.9% and 25% respectively of third instars of M. desjardinsis and C. congrua sp. died before pupation. However, when reared on A. gossypii 82.6% and 46.9% respectively of third instars of M. desjardinsi and C. congrua died before pupation. Thus, H. armigera eggs and A. gossypii nymphs were both adequate but not optimal diets for chrysopid larval development. The number of prey consumed by M. desjardinsi and C. congrua increased with instar. Total larval consumption of H. armigera by M. desjardinsi and C. congrua was determined to be 135.5 and 169.8 eggs respectively. However, total larval consumption of A. gossypii by M. desjardinsi and C. congrua was found to be 189.0 and 171.8 nymphs respectively. Because of its longer larval period, and higher consumption of A. gossypii, M. desjardinsi would be better suited for use against A. gossypii than C. congrua. In contrast, C. congrua whose consumption of H. armigera was higher than that of M. desjardinsi although their larval periods were similar, would appear promising for control of H. armigera.  相似文献   

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17.
This study to detect Tuta absoluta was carried out at four sites in western Burundi from March to July 2018. Delta traps containing Tutrack pheromone and sticky paper were installed in tomato fields at 40 cm from the ground. Sample collection was carried out twice a week. The results confirmed the presence of T. absoluta in Burundi. Effective pest control is required to avoid heavy losses on tomato production.  相似文献   

18.
进口大豆中菌核和麦角的鉴别   总被引:1,自引:0,他引:1  
进口大豆中不断检出的黑色鼠粪状物质,究竟是大豆菌核病菌的菌核还是麦角,是目前困扰口岸检验检疫人员的一个问题。本文对大豆菌核病菌的菌核和麦角的分类地位、寄主及为害症状、形态特征、检疫鉴定方法等方面进行了介绍和比较,以期对今后大豆检疫工作有所帮助。  相似文献   

19.
The Nearctic eastern cherry fruit fly species Rhagoletis cingulata (Loew) (Dipt., Tephritidae) has been detected several times in different European countries during the last decades. This species as well as Rhagoletis indifferens (Curran) are major pests of cultivated cherries in North America and are classified as quarantine pests in Europe. The introduction and establishment of both species could result in severe problems for Austrian cherry production due to additional infestation pressure caused by overlapping developmental cycles of American and native cherry fruit flies. A survey of both non-European cherry fruit fly species was carried out during the growing seasons of 2007 and 2008 at eleven sampling sites in the eastern part of Austria. Pherocon® AM yellow sticky traps were installed in cherry trees and replaced at weekly or fortnightly intervals. Identification of the cherry fruit flies caught was based on morphological characteristics. Two specimens of R. cingulata were caught in 2007 in different weeks and at different locations while none were caught in 2008. R. indifferens was not detected at all. While it is possible that these specimens originate from established populations with low densities, it is more likely that the catches derived from accidental introductions.  相似文献   

20.
Abstract The parasitoid complex of Dasineura saliciperda (Dufour) (Diptera, Cecidomyiidae) on Salix fragilis L. was studied in 1997 and 2002 in two localities in Bulgaria. As a result, 5 species from 3 families of Chalcidoidea (Hymenoptera) were reared from pest galls: Eurytoma afra Boheman, Eurytoma salicis Walker (Eurytomidae), Torymus microcerus (Walker) (Torymidae), Gastrancistrus sp. and Mesopolobus sp. (Pteromalidae). E. afra and T. microcerus are new species for the fauna of Bulgaria, and E. salicis – a new parasitoid of the host. Total parasitism of D. saliciperda in the studied years ranged between 44.1 and 53.5 %. E. afra was the most important, destroying 21.9-53.5 % of the pest.  相似文献   

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