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Wild Form (wild + form)
Selected AbstractsHow mitochondrial DNA diversity can help to understand the dynamics of wild-cultivated complexes.MOLECULAR ECOLOGY, Issue 12 2001The case of Medicago sativa in Spain Abstract In order to clarify the relationships (genetic exchange and shared ancestry) between natural and cultivated populations of alfalfa (Medicago sativa L.) in Spain, we investigated the patterns of mitochondrial DNA variation (characterized through restriction fragment length polymorphism) for 248 individuals in seven natural and six cultivated populations of this species. Mitochondrial variation was evidenced in both natural and cultivated populations of M. sativa. Among the seven mitotypes idengified in the species, two were specific of the natural populations, a result attesting the fact that the Spanish wild form of M. sativa is an original genetic pool compared to the cultivated one. Other mitotypes were observed in both natural and cultivated populations, suggesting the occurrence of gene flow through seeds from cultivated towards natural populations. Comparisons with previously gathered nuclear and phenotypic data give insights into the different evolutionary forces acting on the different kinds of Spanish natural populations examined so far. [source] Anti-tumour and immuno-stimulating activities of the fruiting bodies of Paecilomyces japonica, a new type of Cordyceps spp.PHYTOTHERAPY RESEARCH, Issue 7 2003Kuk Hyun Shin Abstract The anti-tumor and immuno-stimulating activities of the fruiting bodies of Paecilomyces japonica (PJ), grown on silk-worm larvae and of Cordyceps sinensis (CS), a wild form of Cordyceps Fungi, were investigated. Ethanol extracts of both fungi, when administered for 9 consecutive days, at 50 and 100 mg/kg i.p., caused a signi,cant increase in life span and a signi,cant decrease in tumor weights and volumes, in mice inoculated with Sarcoma-180 tumor cells. Both fungal extracts were demonstrated to exhibit phagocytosis enhancing activity as measured by carbon clearance in mice. PJ extracts, when administered i.p. at 50 mg/kg/day for 3 consecutive days, exhibited a signi,cant enhancement of phagocytosis, its potency as expressed by the regression coef,cient ratio, RCtr/RCc, being 1.64 (the phagocytosis index = 2). This was approximately the same for that of zymosan (RCtr/RCc = 1.55, PI = 2), a typical phagocytosis enhancer, whereas CS extracts exhibited a moderate phagocytosis enhancing activity at the same dose level (RCtr/RCc = 1.30, PI = 1). Both fungal extracts caused a signi,cant increase in an acid phosphatase activity, representing lysosomal enzymes, in macrophages at 20 and 100 µg/ml in vitro, in compliance with in vivo results. These results suggest that the anti-tumor activity of both fungi might be related to an immuno-stimulating function. Copyright © 2003 John Wiley & Sons, Ltd. [source] Importance of colour in the reaction of passerine predators to aposematic prey: experiments with mutants of Pyrrhocoris apterus (Heteroptera)BIOLOGICAL JOURNAL OF THE LINNEAN SOCIETY, Issue 1 2006ALICE EXNEROVÁ Persistent questions concerning the warning coloration of unpalatable insects address whether the bright aposematic colour itself or its combination with a species-specific dark pattern is the key factor in their protection against insectivorous birds, and how chromatic polymorphism originates and is maintained in aposematics. In the present study, these questions were tested experimentally, using the birds Parus major, Parus caeruleus, Erithacus rubecula, and Sylvia atricapilla as predators, and chromatically polymorphic firebug Pyrrhocoris apterus: red wild form, white, yellow, and orange mutants (all four of them with the same black melanin pattern, the mutants differing in colour of pteridine pigments only) and the nonaposematic brown-painted wild form as prey. The results show that a specific colour is essential for the birds to recognize the specific aposematic prey; the melanin pattern is not sufficient. White mutants were no better protected than nonaposematic firebugs; red wild-type and orange mutants were equally well protected against all bird species; and the reaction of birds to yellow mutants was species-specific. An evolutionary scenario of 'recurrent recessive mutations' is formulated to explain the origin of colour polymorphism in some aposematics. © 2006 The Linnean Society of London, Biological Journal of the Linnean Society, 2006, 88, 143,153. [source] Escape of farmed tilapiines into the wild and entry of wild forms in fishponds, and the possible interactions between wild and farmed tilapiines from a sample of smallholder farms in Central UgandaAFRICAN JOURNAL OF ECOLOGY, Issue 4 2009Matthew Tenywa Mwanja Abstract Seven smallholder fishponds in central Uganda were studied between 2000 and 2001 to investigate the interaction of farmed tilapiines with their wild conspecifics. Emphasis was on the features that facilitate escape of fish and/or entry of fish into the farms and interactions between the farmed and the wild. These included number of species, source of seed, connection between pond and natural watercourses, purpose of the farm, destination of cultured fish and interaction between farmed and wild fish. Fishponds had no screens against entry of wild fish into the farm or escape of farmed fish into the wild and occurred within wetlands close to natural watercourses. Ponds stocked with one fish species were found to have multispecies with some individuals that were apparently intermediate morphs between the species. Fry produced within the growout fishponds was shared with other farmers within and outside the watersheds. This study showed that smallholder farms with little or no control of escape or entry of fish out and into the fishponds, and little or no management present circumstances that facilitate continued movement of tilapiines within and across watersheds in Ugandan waters. The study also indicated possible genetic interaction between farmed and their wild conspecifics through interactions within fishponds. Résumé Sept viviers appartenant à de petits propriétaires ont étéétudiés entre 2000 et 2001 pour rechercher l'interaction entre les tilapiinés d'élevage et ceux qui vivent dans la nature. On insistait sur les caractéristiques qui facilitent la fuite et/ou l'entrée des poissons dans les fermes et les interactions entre les poissons d'élevage et les poissons sauvages. On a étudié le nombre d'espèces, la source de la progéniture, les connections entre les bassins et les cours d'eau naturels, la raison d'être des fermes, la destination des poissons d'élevage et l'interaction entre les poissons d'élevage et les poissons sauvages. Les réservoirs n'avaient pas de filtres pour empêcher l'entrée des poissons sauvages ou la fuite des poissons d'élevage et ils se trouvaient dans des zones humides proches de cours d'eau naturels. Les bassins qui avaient été stockés avec une seule espèce de poissons se sont avérés contenir plusieurs espèces, et certains individus semblaient avoir une morphologie intermédiaire entre différentes espèces. Le fretin produit dans les bassins de croissance était partagé avec d'autres éleveurs dans ou en dehors des bassins versants. Cette étude a montré que les petits élevages qui exercent peu de contrôles sur les entrées ou les sorties de poissons dans et hors des bassins et une gestion nulle ou très réduite, offrent des conditions qui facilitent le déplacement continu des tilapiinés au sein des bassins de rivières et entre eux, dans les eaux ougandaises. Cette étude indique aussi qu'il est possible qu'il existe des interactions génétiques entre les poissons d'élevage et les poissons sauvages de même espèce, au niveau des bassins d'élevage. [source] Development of DNA microsatellite markers in the Andean root crop arracacha: Arracacia xanthorrhiza Banc. (Apiaceae)MOLECULAR ECOLOGY RESOURCES, Issue 4 2004E. MORILLO Abstract A microsatellite-enriched library was constructed in the Andean root crop arracacha (Arracacia xanthorriza B). Of 18 loci tested, 14 were found to be polymorphic after screening for diversity in different cultivars and related wild forms. Allelic diversity in the crop was low but the transferability of the primers to closely related wild forms was good. The loci reported here are the first genetic markers to be published for this species and will be useful for future germplasm characterization and studies of genetic diversity. [source] | ||||||||||