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1.
Legume Seeds: the Defences of Wild and Cultivated Species of Phaseolus Against Attack by Bruchid Beetles 总被引:5,自引:0,他引:5
A range of accessions (182) of wild, semi-cultivated and cultivatedPhaseolus were subjected to attack by two Old World bruchids,Callosobruchus maculatus and Caliosobruchus chinensis and twoNew World bruchids Zabrotes subfasciatus and Acanthoscelidesobtectus. Six different stages in the progression of the brochid-legumeinteraction, at which resistance may occur, are described andassessed. Resistance is shown by: no oviposition; disruptedembryo development; failure of larvae to penetrate the testa;death of larvae within the cotyledon; failure of pupation oradult emergence; reduced fitness of adults. The occurrence ofresistance at each of these stages is discussed in the contextof possible causal mechanisms. The patterns of resistance tothe two pairs of bruchids of different geographical origin isconsidered in relation to co-evolutionary processes Phaseolus, wild species, resistance, bruchids, Callosobruchus maculatus, Callosobruchus chinensis, Zabrotes subfaciatus, Acanthoscelides obtectus 相似文献
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Gold salts and phenylbutazone selectively inhibit the synthesis of PGF2α and PGE2 respectively. Lowered production of one prostaglandin species is accompanied by an increased production of the other. Selective inhibition by these drugs was observed in the presence of adrenaline, reduced glutathione and copper sulphate under conditions when most anti-inflammatory compounds inhibited PGE2 and PGF2α syntheses equally. It is postulated that selective inhibitors may have a different mode of action
and beneficial effects may be related to the endogenous ratio of PGE to PGF required for normal function. 相似文献
5.
A number of synthetic auxins and auxin-antagonists were appliedin lanolin emulsions to young banana fruits and their effectson fruit development and seed fertility estimated. Auxins stimulatedthe formation of edible pulp in both seedy and parthenocarpicbananas and induced varying degrees of seed sterility. Of theauxin antagonists tried, coumarin (contrary to a mistaken earlierreport) stimulated parthenocarpy and induced seed sterility,three others were not or but slightly active, and thiourea markedlyinhibited parthenocarpy. Study of the relation between sizeof mature fruit and seed content indicates that developing seedsstimulate the growth of pulp and that the amount of stimulationis roughly proportional to the level of parthenocarpy. Fruitdevelopment in the banana seems to fit in with Luckwill's generalscheme of dual hormonal stimulus. 相似文献
6.
Pasquier CM; Promponas VI; Varvayannis NJ; Hamodrakas SJ 《Bioinformatics (Oxford, England)》1998,14(8):749-750
Summary : FT is a tool written in C++, which implements the Fourier
analysis method to locate periodicities in aminoacid or DNA sequences. It
is provided for free public use on a WWW server with a Java interface.
Availability : The server address is http://o2.db. uoa.gr/FT Contact :
shamodr@atlas.uoa.gr
相似文献
7.
JF Yuan SJ Zhang O Jafer RA Furlong OE Chausiaux CA Sargent GH Zhang NA Affara 《BMC microbiology》2009,9(1):246
Background
Pseudorabies virus (PRV) is an alphaherpesviruses whose native host is pig. PRV infection mainly causes signs of central nervous system disorder in young pigs, and respiratory system diseases in the adult. 相似文献8.
In a variety of tumour systems, individuals carrying progressively growing neoplasms have lymphoid cells with a specific cytotoxic effect on cultured tumour cells from the same individual1–4. Since the sera of tumour-bearing individuals have been shown to prevent tumour cell destruction by immune lymphocytes in vitro2,5–8 and since this serum blocking activity appears early in primary and transplant tumour development5,7, it has been suggested that the appearance of this serum blocking activity might be responsible for the progressive growth of tumours in individuals having cytotoxic lymphocytes. Counteraction of this blocking activity would thus be of primary importance in facilitating the function of an already existing or bolstered cell-mediated immunity. The serum blocking activity might be inhibited in various ways, by preventing the formation of blocking antibody or by interfering with its action (“unblocking”), as demonstrated in Moloney sarcoma regressor sera9. This type of serum also has a therapeutic effect on Moloney sarcomas in vivo10,11, which has been tentatively attributed to its unblocking activity8,9 or, possibly, to a complement-dependent cytotoxicity10. Tumour growth in the Moloney sarcoma system, however, might be due in part to continuous recruitment of neoplastic cells by virus-induced transformation and so the therapeutic effect could be due to a virus-neutralizing serum activity9,10. 相似文献
9.
MONIQUE VIANEY‐LIAUD HELDER GOMES RODRIGUES LAURENT MARIVAUX 《Zoological Journal of the Linnean Society》2010,160(3):531-550
The four living genera of Ctenodactylidae (Rodentia) are the only survivors of a flourishing Tertiary group. In this paper, we describe a new Oligocene species from Ulantatal (Chinese Mongolia) that highlights the origins of crown ctenodactylids. This species, Helanshania deserta gen. et sp. nov. , is lophodont and displays semi‐hypsodont teeth, a dental pattern that is somewhat transitional between that of primitive Oligocene ctenodactylids and the later hypsodont genera. We perform here a cladistic assessment of the dental evidence for species produced by the successive radiations of the group. In order to get new data, to decipher homologies for the dental pattern of modern ctenodactylids, and to specify their dental replacement, we describe additional dental material of Ctenodactylus, Massoutiera, and Felovia. The phylogenetic analysis (using PAUP) considered 45 characters (mainly dental) and 31 species. The performed heuristic searches yielded 596 equally most parsimonious trees. Protataromys and Karakoromys are stem ctenodactylids and appear as the earliest offshoots of the Ctenodactylidae clade, which represents a well‐supported family rank. Within this family, the Tataromyinae appear paraphyletic, whereas the Ctenodactylinae sensu lato are a clade including the new taxon Helanshania. As such, a revision of the Tataromyinae is envisaged and a new subfamily is erected (Yindirtemyinae). Amongst the Ctenodactylinae, a tribe Ctenodactylini encompassing the crown ctenodactylines is proposed. © 2010 The Linnean Society of London, Zoological Journal of the Linnean Society, 2010, 160 , 531–550. 相似文献
10.
Hsin-Chou Yang Mei-Chu Huang Ling-Hui Li Chien-Hsing Lin Alice LT Yu Mitchell B Diccianni Jer-Yuarn Wu Yuan-Tsong Chen Cathy SJ Fann 《BMC bioinformatics》2008,9(1):196