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1.
The pollen grains of 69 specimens representing 44 species or supposed species of the genus Waltheria L. have been studied. Based mainly on differences in exine characters 2 pollen types, a spinulose and a suprareticulate one were pointed out. Both types show ± parallel trends in the development of the aperture system to an increase of aperture number, to a shortening of the colpi and to more distinct bounds and nexine thickenings of the ora. They exemplify important steps of aperture evolution, which in the spinulose type leads from zonocolporate by way of zonopororate to pantopororate and in the suprareticulate type from zonocolporate to pantocolporate grains. The tendencies of sporoderm evolution concern a more distinct morphological and partially also a regional differentiation of the exine elements (bacula, spinulae), which prove to be close correlated with the evolution levels of the apertures. According to the pollen morphological point of view the species of the genus Waltheria are to be arranged in two groups, which may be regarded as two related, but relative independent phyletic entities. These evidences speak in favour of a taxonomic  相似文献   

2.
The relative resistance and susceptibility of various cruciferous plants to swede midge, Contarinia nasturtii (Kieffer) (Diptera: Cecidomyiidae), damage was investigated to provide growers with planting recommendations and to identify potential sources of resistance to the swede midge. Broccoli cultivars experienced more severe damage than cabbage, cauliflower, and Brussels sprouts. The broccoli 'Paragon', 'Eureka', and 'Packman' are highly susceptible to the swede midge, whereas 'Triathlon' and 'Regal' showed reduced susceptibility to damage and slower development of damage symptoms. No differences were found between normal and red cultivars of cabbage and cauliflower in damage severity and progression of damage symptoms. Four new plant species (Brassica juncea Integlifolia group, Erucastrum gallicum (Willd.) O. E. Shulz., Lepidium campestre (L.) R.Br., and Capsella bursa-pastoris (L.) Medic.) are reported as hosts of the swede midge. The weed species Descurainia sophia (L.) Webb, Camelina microcarpa Andrz. ex Dc., and Erysimum cheiranthoides L. exhibited no damage symptoms, and they seem to be nonhost crucifers for the swede midge.  相似文献   

3.
The hitherto unknown larva of Lopesia spinosa Maia (Diptera: Cecidomyiidae) is described and the geographical distribution of the species is extended in Brazil to Delfinópolis in Minas Gerais; Altinópolis and Jundiaí in São Paulo. Diagnostic characters of the species and illustration of the larva are presented.  相似文献   

4.
5.
The blueberry gall midge, Dasineura oxycoccana Johnson, is a serious pest of rabbiteye blueberries in Florida, Georgia, and Mississippi, and a potential pest of southern and northern highbush blueberries. Its damage has been observed with increasing frequency in highbush blueberry plantings in the Great Lakes region, including in Wisconsin and in Michigan. Unlike in rabbiteye blueberry plantings, where blueberry gall midge primarily damages flowering buds, it is found to damage only the vegetative shoots of northern highbush blueberry. In this study, farms throughout Michigan were surveyed for the presence of blueberry gall midge and it was found in 43 of 46 sampled farms in 11 counties. From 2009-2011, several monitoring techniques, including yellow sticky traps, emergence traps, observational sampling, and vegetative shoot dissections were used to determine the ecology of this species in blueberry fields in southwest Michigan. Emergence traps were most useful in early detection of blueberry gall midge in April, and observational sampling for damage symptoms and vegetative shoot dissections revealed multiple population peaks throughout July and August. Infestation was detected in vegetative shoot tips in all parts of the bushes, with initial infestation greatest at the base of bushes. Degree day accumulations until first midge detection and peak infestation suggest some potential for predicting key events in the pest's phenology. This information about the distribution and timing of infestation will be useful in developing management strategies for blueberry gall midge infestation.  相似文献   

6.
The toxicity of 98 plant essential oils against third instars of cecidomyiid gall midge Camptomyia corticalis (Loew) (Diptera: Cecidomyiidae) was examined using a vapor-phase mortality bioassay. Results were compared with that of a conventional insecticide dichlorvos. Based on 24-h LC50 values, all essential oils were less toxic than dichlorvos (LC50, 0.027 mg/cm3). The LC50 of caraway (Carum carvi L.) seed, armoise (Artemisia vulgaris L.), clary sage (Salvia sclarea L.), oregano (Origanum vulgare L.), lemongrass [Cymbopogon citratus (DC.) Stapf], niaouli (Melaleuca viridiflora Gaertner), spearmint (Mentha spicata L.), cassia especial (Cinnamomum cassia Nees ex Blume), Dalmatian sage (Salvia offcinalis L.), red thyme (Thymus vulgaris L.), bay [Pimenta racemosa (P. Mill.) J.W. Moore], garlic (Allium sativum L.), and pennyroyal (Mentha pulegium L.) oils is between 0.55 and 0.60 mg/cm3. The LC50 of cassia (C. cassia, pure and redistilled), white thyme (T. vulgaris), star anise (Illicium verum Hook.f.), peppermint (Mentha X piperita L.), wintergreen (Gaultheria procumbens L.), cinnamon (Cinnamomum zeylanicum Blume) bark, sweet marjoram (Origanum majorana L.), Roman chamomile [Chamaemelum nobile (L.) All.], eucalyptus (Eucalyptus globulus Labill.), rosemary (Rosmarinus officinalis L.),Virginian cedarwood (Juniperus virginiana L.), pimento berry [Pimenta dioica (L.) Merr.], summer savory (Satureja hortensis L.), lavender (Lavandula angustifolia Mill.), and coriander (Coriandrum sativum L.) oils is between 0.61 and 0.99 mg/cm3. All other essential oils tested exhibited low toxicity to the cecidomyiid larvae (LC50, >0.99 mg/cm3). Global efforts to reduce the level of highly toxic synthetic insecticides in the agricultural environment justify further studies on the active essential oils as potential larvicides for the control of C. corticalis populations as fumigants with contact action.  相似文献   

7.
Youngomyia matogrossensis Proença & Maia a new species of Cecidomyiidae (Insecta: Diptera) that induces cylindrical hairy galls on leaves of Pouteria torta (Mart.) Radlk. (Sapotaceae) is herein described and illustrated (larvae, pupal exuviae, male and female). The galler, gall and host plant were collected at Parque Nacional da Chapada dos Guimarães, in the state of Mato Grosso (Brazil). New morphological data and photographs of pupal exuviae, male and female of Youngomyia pouteriae Maia, 2001 are also provided.  相似文献   

8.
A list of the 356 species of Cecidomyiidae (Diptera) recorded from Finland is presented, which comprises 6 Lestremiinae, 156 Micromyinae, 16 Winnertziinae, 69 Porricondylinae, and 109 Cecidomyiinae. The faunistic knowledge of Finnish Winnertziinae, Porricondylinae and Cecidomyiinae is regarded as particularly poor. Based on species numbers known from other countries in Europe, a conservative estimate is 700–800 species of Cecidomyiidae actually occurring in Finland.  相似文献   

9.
The genus Bruggmanniella Tavares is newly discovered from Taiwan and Bruggmanniella brevipes sp. n. is described as new to science. This is the southernmost species of Bruggmanniella found in the Old World. Furthermore, the gall midge induces bud galls on Neolitsea parvigemma (Hayata) Kaneh (Lauraceae), an endemic species in Taiwan, and the plant genus Neolitsea is the third host genus of Lauraceae-associated Bruggmanniella in East Asia. The knowledge of its distribution and host information provide us to shed the light on evolutionary and biogeography issue of East Asian Bruggmanniella.www.zoobank.org/urn:lsid:zoobank.org:pub:820320EC-17BC-4E00-A401-2DBDA3EEE9C4  相似文献   

10.
Procystiphora uedai sp. nov., a cecidomyiid inducing subglobular galls on Sasa nipponica Makino and Shibata on Mount Ôdaigahara, Nara Prefecture, Japan is described herein. This species is distinguishable from the three known congeners by the following characteristics of the female post-abdomen: tergite VIII concave at both anterior and posterior margins; tergites VII, VIII and sternite VII unsclerotized; ovipositor–dorsoventrally inverted. Most individuals of this gall midge are univoltine and pupate in the galls in early September, but some individuals enter prolonged diapause at the third larval stadium and remain in the mature galls until the following year. Larvae of this species are attacked by two parasitoid species, Pediobius sasae Hansson (Eulophidae) and Torymus sp. (Torymidae).  相似文献   

11.
Many hypotheses have been proposed to explain the diversity of gall-midge insects (Diptera: Cecidomyiidae), some of them taking into account plant diversity. This study aims to test the importance of size, age and composition of host plant taxa in the diversity of Cecidomyiidae. For this we used inventories data on the diversity of galling and host plants in Brazil. We found that Asterales, Myrtales and Malpighiales, were the most important orders, with 34, 33 and 25, gall morphotypes, respectively. The most representative host families were Asteraceae (34 morphotypes), Myrtaceae (23) and Fabaceae (22). In general, the order size and the plant family were good predictors of the galling diversity, but not the taxon age. The most diverse host genera for gall-midges were Mikania, Eugenia and Styrax, with 15, 13 and nine galler species, respectively. The size of plant genera showed no significant relationship with the richness of Cecidomyiidae, contrary to the prediction of the plant taxon size hypothesis. The plant genera with the greatest diversity of galling insects are not necessarily those with the greatest number of species. These results indicate that some plant taxa have a high intrinsic richness of galling insects, suggesting that the plant species composition may be equally or more important for the diversity of gall-midges than the size or age of the host taxon.  相似文献   

12.
13.
The Hessian fly, Mayetiola destructor (Say), is an important insect pest of wheat (Triticum spp.) in North Africa, North America, southern Europe and northern Kazakhstan. Both wheat and this pest are believed to have originated from West Asia in the Fertile Crescent. The virulence of a Hessian fly population from Syria against a set of cultivars carrying different resistance genes, in addition to other effective sources with unknown genes, was determined in the field and laboratory at the International Center for Agricultural Research in the Dry Areas (ICARDA) during the 2005/2006 cropping season. Only two resistance genes (H25 and H26) were effective against the Syrian Hessian fly population, making it the most virulent worldwide. This high virulence supports the hypothesis that Hessian fly coevolved with wheat in the Fertile Crescent of West Asia. The ICARDA screening programme is using this Hessian fly population to identify new resistance genes to this pest.  相似文献   

14.
15.
刺槐叶瘿蚊广腹细蜂Platygaster robiniae Buhl and Duso(膜翅目:细蜂科)是我国外来有害生物刺槐叶瘿蚊Obolodiplosis robiniae(Haldeman)(双翅目:瘿蚊科)十分重要的寄生性天敌,为卵-幼虫跨期寄生蜂,专化性强,在自然抑制害虫虫口密度中起着非常重要的作用。为摸清刺槐叶瘿蚊广腹细蜂在我国的地理分布,探讨其与刺槐叶瘿蚊的相互关系,本文根据寄主刺槐叶瘿蚊在我国的分布范围,采用踏查的方法,对全国17个省、市、自治区的29个地区进行了调查。结果显示,刺槐叶瘿蚊广腹细蜂在其寄主分布区都有分布,分布范围在26°35.451′-43°53.482′N,103°51.816′-125°15.969′E,海拔4-1 097 m。  相似文献   

16.
Numerous crystalline inclusions are found in the nutritive cells lining the larval cavities of the galls induced by Diplolepis rosae L. on Rosa canina L. Electron microscopic investigations show that these intracytoplasmic inclusions consist of staggered, closely parallel, and slightly wavy filaments. In each filament three fibrils can be distinguished inside a less electron-dense matrix. The different aspects that the filaments may present according to the section plans are studied with an electron microscope equipped with a goniometric stage. Enzymatic digestion of ultrathin sections show that the paracrystals are essentially composed of proteins. This conclusion is sustained by the results of an ultrastructural autoradiographic study using tritiated aminoacids. The physiological significance of these paracrystals is discussed: their presence is probably related to a larval action which stimulates proteosynthesis in the cells surrounding the consumed ones.  相似文献   

17.
Optimal culture conditions for high frequency plant regeneration from excised cotyledons of Tamarindus indica were established. Maximum shoot bud differentiation (100%) occurred when the adaxial surface of the entire cotyledon (excised from 12-d old seedlings) was in contact with MS medium containing 5×10–6M BAP. On MS alone only roots were formed. Shoot or root formation was confined to nodal tissue at the top of the notch present on the adaxial surface at the proximal end of the cotyledon. Thirty-four to 95 shoots were regenerated in a 4 month period from individual cotyledons. Shoots were rooted on MS with 5.7×10–6M IAA. IAA (5.7×10–7M) alone induced complete plant formation. Regenerated plants were established in the soil with 70% success.Abbreviations BAP 6-benzylaminopurine - KIN kine-tin - 2-iP 6-Y-Y-dimethylallyl aminopurine - AdS adenine sulphate - IAA indole-3-acetic acid - IBA indole-3-butyric acid - NAA 1-naphthalene acetic acid - MS Murashige and Skoog (1962) medium  相似文献   

18.
The seasonal development of the swede midge Contarinia nasturtii Kieffer was studied in Quebec in 2004 and 2005 using pheromone traps, emergence cages, and visual inspection in relation to degree-day accumulations (DD(7.2 degrees C)). Peak emergence of overwintering adults occurred between 344 and 731 DD(7.2 degrees C) (second half of June) during both seasons. The swede midge had three to four overlapping generations in Quebec based on adult captures in pheromone traps and abundance of larvae in the field. The level of infestation was higher in late transplants than in early transplants, with cauliflower and broccoli being more susceptible to damage than white or red cabbage under high pest population.  相似文献   

19.
Abstract  To quantify the role of Johnson grass, Sorghum halepense , in the population dynamics of the sorghum midge, Stenodiplosis sorghicola , patterns of flowering of Johnson grass and infestation by sorghum midge were studied in two different climatic environments in the Lockyer Valley and on the Darling Downs in south-eastern Queensland for 3 years. Parasitism levels of S. sorghicola were also recorded. In the Lockyer Valley, Johnson grass panicles were produced throughout the year but on the Darling Downs none were produced between June and September. In both areas, most panicle production occurred between November and March and infestation by S. sorghicola was the greatest during this period. The parasitism levels were between 20% and 50%. After emergence from winter diapause, one to two generations of S. sorghicola developed on S. halepense before commercial grain sorghum crops were available for infestation. Parasitoids recorded were: Aprostocetus diplosidis , Eupelmus australiensis and two species of Tetrastichus. Relationships between sorghum midge population growth rate and various environmental and population variables were investigated. Population size had a significant negative effect ( P  < 0.0001) on population growth rate. Mortality due to parasitism showed a significant positive density response ( P  < 0.0001). Temperature, rainfall, open pan evaporation, degree-days and host availability showed no significant effect on population growth rate. Given the phenology of sorghum production in south-eastern Queensland, Johnson grass provides an important bridging host, sustaining one to two generations of sorghum midge. Critical studies relating population change and build-up in sorghum to sorghum midge populations in Johnson grass are yet to be performed.  相似文献   

20.
Summary The parasitoids known to attack 191 phytophagous species of gall midges (Cecidomyiidae) were used to examine factors influencing parasitoid assemblage size. The number of parasitoid species a midge species supports was tested against nine variables describing geographical, biological and ecological attributes of hosts. The apparency of midge larvae was found to have the greatest influence on parasitoid assemblage size; highly visible species support more parasitoids than less visible ones. Pupation site and midge voltinism also significantly affect associated parasitoids, at least for highly apparent hosts. Biogeographic region, host-plant architecture and the plant parts infested were found to be of secondary importance. The surface texture of infested plant parts, the number of midge larvae occupying galls and the diversity of plant tissues infested have minimal apparent effects on parasitoid richness. Parasitoid assemblage size and total parasitism rates were also found to be positively correlated for 73 galling and nongalling midge species, and gallers typically suffer higher levels of parasitism than non-gallers. Using these data to test the enemy hypothesis, which proposes that the galling habit has evolved to escape attack from parasitoids, we conclude that parasitoid pressure cannot account for the presence of galls in the Cecidomyiidae.  相似文献   

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