278,216 research outputs found

    Life History, Damage, and Gall Development of the Gall Midge, \u3ci\u3eNeolasioptera Brevis\u3c/i\u3e (Diptera: Cecidomyiidae), Injurious to Honeylocust in Michigan

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    Neolasioptera brevis is univoltine in Michigan. Adults issue in late spring, and females deposit eggs in rows on the lower side of young shoots of honeylocust. Larval eclosion occurs shortly after: there are three larval instars. The gall is polythalamous and may have 20 or more larvae. The third-instar larvae overwinter, and pupation occurs in spring. The gall injury kills sorne shoots, but most damage is cosmetic. One can monitor for adult emergence in late April or May by observing cast pupal cases protruding from the gall. Control, if needed, should be directed at adults

    Are plants with anti-cancer activity resistant to crown gall? : A test of hypothesis

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    The Crown gall tumour assay (CGTA) is one of several bench top bioassays recommended for the rapid screening of plants with anti-cancer activity. The rationale for the use of the bioassay is that the tumorogenic mechanism initiated in plant tissues by _Agrobacterium tumefaciens_ is in many ways similar to that of animals. Several plant species with anti-cancer activity have already been discovered using this bioassay. However till date no explicit test of an association between anti-cancer activity of plants and their resistance to crown gall formation has been demonstrated. Demonstration of an association could have exploratory potential when searching for plants with anti-cancer activity. In this paper, we determined whether or not a statistically significant association between crown gall resistance and anti-cancer activity exists in plants found in existing published data sets. Our results indicate that plants with anti-cancer activity have a higher proportion of their species resistant to crown gall formation compared to a random selection of plants. We discuss the implications of our results especially when prospecting for newer sources of anti-cancer activity in plants

    Effects of distention of the small intestine on the movements of the gallbladder and the sphincter of Oddi

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    1. Dogs anesthetized with pentobarbital sodium were mainly used and effects of the distention of the small intestine on the movements of the gall bladder and the sphincter of Oddi were investigated. 2. The distention of the small intestine (jejunum or ileum) inhibited the rhythmic contraction of the gall bladder and duodenal movements, and relaxed the tone of the sphincter of Oddi, resulting in an increase of the outflow of fluid through the orifice of the common bile duct. 3. After cutting the bilateral thoracic splanchnic nerves together with extirpation of the bilateral upper lumbar sympathetic trunks, the inhibitory response on the movements of the gall bladder and the tone of the sphincter of Oddi was completely abolished. The vagus nerve did not take part in the reflex response described above. The transection of the spinal cord at the level between Thl and Th2 produced no change in the reflex responses. 4. Fwm the results described above it may be supposed that effects of the distention of the small intestine on the movements of the gall bladder and the sphincter of Oddi are produced via the thoracic and lumbar splanchnic nerves through the reflex center which is located in the spinal cord.</p

    Dasineura papaveris (Winnertz, 1853) - new record of a gall-midge from Malta (Diptera, Cecidomyiidae)

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    New record of a gall-midge from Maltapeer-reviewe

    Three people's view of the future of gall research

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    At the 25th anniversary of the British Plant Gall Society three colleagues who have been working for more than 20 years with cynipid gall systems provide a broad view of what has happened in the field and what questions might be most interesting for the near future to tackle. They fall broadly in five areas: How do they induce galls? How did galling evolve? Why do galls come in such amazing shapes and sizes? And how can we tell the inhabitants apart

    The Pocket Encyclopedia of Plant Galls. Arnold Darlington. New York: Philosophical Library, 1968.191 pp. $7.50.

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    Excerpt: Plant galls or cecidia have always fascinated and bewildered the biologist and the layman, and only recently has there been much attention paid to the biology of gall makers and the physiology of gall development. There are several \u27early\u27 definitive books on galls by British, German, and American authors, but most are out of print or are replete with errors. Few are useful for quick identification of galls in the field

    Eriophyoid mites (Acari: Prostigmata: Eriophyoidea) from the Maltese Islands (Central Mediterranean): new reports and a preliminary check-list

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    In the 20th Century, about 20 species of eriophyoids were listed for the Maltese Islands but these reports were entirely based on plant gall surveys. In these last four years, plant collections were made in order to investigate the species of eriophyoids present in Malta and Gozo. Most of the earlier reports have been confirmed and eight species were found to be new for the Maltese islands: Aceria caulobia (Nalepa) gall-making on Suaeda vera Gmelin; Aceria onychia (Nalepa) on Phlomis fruticosa L.; Aceria sheldoni (Ewing) on lemon; Aculus tetanothrix (Nalepa) gall-making on Salix sp.; Cecidophyopsis hendersoni (Keifer) on yucca; and three species associated with olive, Ditrymacus athiasella Keifer, Oxycenus maxwelli (Keifer) and Tegolophus hassani ( Keifer). Additional remarks were included for Acalitus phloeocoptes (Nalepa), collected on cherry plum, whose earlier Maltese record was doubtful. A complete morphometric description of Aceria carlinae (Nalepa) is here provided.peer-reviewe

    Clonal mixing in the soldier-producing aphid <i>Pemphigus spyrothecae</i> (Hemiptera: Aphididae)

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    Illuminating the genetic relationships within soldier-producing aphid colonies is an essential element of any attempt to explain the evolution of the altruistic soldier caste. Pemphigus spyrothecae is a soldier-producing aphid that induces galls on the leaf petioles of its host (trees of the genus Populus). At least a quarter of the aphids within the clonally produced gall population are morphologically and behaviourally distinct first-instar soldiers that defend the gall population from predation. Using field trapping and microsatellites, we investigated the degree of clonal mixing within natural gall populations. Field trapping in the UK showed that all the migrants of P. spyrothecae and of two other Pemphigus species were wingless first-instar soldiers. The average degree of mixing estimated from trapping P. spyrothecae migrants was 0.68% (range = 0–15%). Microsatellite genotyping of 277 aphids from 13 galls collected in Italy revealed an average mixing level of 10.4% (range = 0–59%). Six galls contained more than one clone (range = 2–5 clones). Non-kin aphids were not restricted to the soldier caste but were evenly distributed across instars. An additional gall, from which 527 occupants were genotyped, contained 12 non-kin aphids distributed among nine clones, showing that clonal diversity can be high even when mixing is very low. These observations suggest that although soldiers migrate regularly and can moult and reproduce within foreign galls, clonal mixing in this species is generally low and is unlikely to provide a barrier to the evolution of investment by the aphid clones in an altruistic soldier caste

    Rediscovery of a rare gall on Rosa sempervirens induced by Diplolepis eglanteriae (Hartig, 1840) (Hymenoptera, Cynipidae) in Malta

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    Diplolepis eglanteriae is a cynipid wasp inducing characteristic smooth pea-like galls on Rosa sempervirens. The gall was first reported as occurring in Malta in 1926 at Buskett. During the present study, the presence of this gall was confirmed and although it was not found again in Buskett it was found in three other localities on Malta. Three chalcid parasitoids were found associated with these galls, namely Eupelmus (Macroneura) muellneri Ruschka, 1921 (Eupelmidae), Stepanovia eurytomae (Nees, 1834) (Eulophidae) and Pteromalus sp. near bedeguaris (Pteromalidae); the latter two are here recorded for the first time from the Maltese Islands.peer-reviewe

    African Art: What and to Whom? Anxieties, Certainties, Mythologies

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    It has taken nearly a whole century to publish two books on African art that recognize the continent as a complex cultural unit within which there is diversity, A History of Art in Africa (Blackmun Visona, M et al, 2001) and Africa, The Art of a Continent (Phillips, T. 1995). Why it taken so long far North and East Africa past and present to be included in texts labeled African art? Why were they not recognized as African? India, also a place of diversity of race and ethnicity, has not similarly treated. The assumptions underlying the norms a representation of Africa were deeply rooted, their influence scholarship related to African art and culture was profound and, even if attenuated at present, persistent. They have impacted on the organization of information related to Africa, influencing from cataloging, the content of texts and videos, to museum layout exhibitions. Only by becoming conscious of the pervasive power of this hidden curriculum can we take steps to counter its influence. Those underlying assumptions are symptomatic of European fear5aJlII desires related to African identity
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