Search results for "antagonism"

Pythium deliense causing severe damping-off of cucumber seedlings and its biological control by soil bacteria

1996

Abstract Pythium deliense Meurs was isolated from cucumber plant debris and was found to be highly pathogenic to cucumber seedlings, causing severe damping-off disease. The fungus however was completely inhibited by a soil bacterium SU-48.1. In vitro and in vivo studies reveal that the disease can be controlled by using this bacterium. The details of the parasitic fungus, the antagonism between the fungus and the bacteria, and the biological control of the disease, are described in this article.

Probiotic properties of Brevibacillus brevis and its influence on sea bass (Dicentrarchus labrax) larval rearing

2012

Efficacy of Brevibacillus brevis strain and its influence on larval rearing of sea bass (Dicentrarchus labrax) were investigated in the present work. Biochemical analyses permit to identify this strain as B. brevis. This bacterium has an inhibitory effect against fish pathogenic bacteria, especially the genus of Vibrio. Enzymatic characterization revealed that B. brevis was lipase positive, amylase, lecithinase and caseinase negative. Adherence assays to abiotic surfaces and challenge test with Artemia larvae demonstrate that B. brevis was fairly adherent and play an important role in the enhancement of the protection of Artemia culture against pathogens. Treatment of sea bass larvae with B…

Phenazine antibiotics produced by fluorescent pseudomonads contribute to natural soil suppressiveness to Fusarium wilt

2009

Natural disease-suppressive soils provide an untapped resource for the discovery of novel beneficial microorganisms and traits. For most suppressive soils, however, the consortia of microorganisms and mechanisms involved in pathogen control are unknown. To date, soil suppressiveness to Fusarium wilt disease has been ascribed to carbon and iron competition between pathogenic Fusarium oxysporum and resident non-pathogenic F. oxysporum and fluorescent pseudomonads. In this study, the role of bacterial antibiosis in Fusarium wilt suppressiveness was assessed by comparing the densities, diversity and activity of fluorescent Pseudomonas species producing 2,4-diacetylphloroglucinol (DAPG) (phlD+) …

Microorganisms and Biotic Interactions

2014

SPE IPM; Most ecosystems are populated by a large number of diversified microorganisms, which interact with one another and form complex interaction networks. In addition, some of these microorganisms may colonize the surface or internal parts of plants and animals, thereby providing an additional level of interaction complexity. These microbial relations range from intraspecific to interspecific interactions, and from simple short-term interactions to intricate long-term ones. They have played a key role in the formation of plant and animal kingdoms, often resulting in coevolution; they control the size, activity level, and diversity patterns of microbial communities. Therefore, they modul…

Characterisation of Pythium paroecandrum and its antagonism towards Botrytis cinerea, the causative agent of grey mould disease of grape.

2004

Pythium paroecandrum (B-30), an oomycete, was isolated from soil samples taken from a wheat field in Genlis in the Burgundy region of France and was found to check the growth and development of Botrytis cinerea, a serious grapevine pathogen. The oomycete is a fast-growing organism, living on vegetable debris, and can be recognised by its catenulate hyphal swellings, catenulate oogonia, and monoclinous antheridia. When grown together with B. cinerea, the causal agent of the grey mould disease of the grapevine, P. paroecandrum shows a pronounced antagonism and suppresses its growth and its aptitude to provoke the grey mould symptoms. Morphological features of this oomycete, its antagonism to …

"In vitro" antagonism of a grapevine endophytic Bacillus subtilis strain towards "esca" fungi.

2008

Preliminary investigations on grapevines (CV Catarratto) with symptoms of “esca” permitted to isolate only bacterial colonies, from black punctuations belonging to the genus Bacillus. Particularly, an isolate was Gram-positive with spore forming and, on the basis of the partial 16S rRNA sequence comparison, it showed a similarity of 99% with Bacillus subtilis subsp. subtilis. There are numerous reports on the antagonistic activity of the species towards several phytopathogenic microorganisms. For this reason the possible bacterial control against the “esca” fungi (Phaeoacre- monium aleophilum, PAL; Phaemoniella clamidospora, PCH; Fomitiporia mediterranea, FOMED), was studied. The antagonist…

Pienskābo baktēriju izdalīšana un identifikācija no Latvijā ražotiem svaigiem un tradicionāli sālītiem gurķiem ar mērķi inhibēt svaigo dārzeņu patogē…

2019

Šī darba mērķis bija izstrādāt svaigu dārzeņu apstrādes metodi, lai aizsargātu tos pret mikroorganismiem, kuri izraisa augu slimības un ir saistīti ar svaigu dārzeņu kvalitātes pasliktināšanos. Mērķa sasniegšanai izmantoja mikroorganismu spējas inhibēt citu mikroorganismu augšanu (antagonismu). Ir pierādīts, ka pienskābes baktērijām piemīt antagonistiskās spējas. Tāpēc par izpētes objektu bija izvēlētas pienskābes baktērijas, kuras bija izolētas no vietējo ražotāju svaigiem un sālītiem gurķiem. No svaigiem un sālītiem gurķiem tika izdalīti 133 pienskābo baktēriju izolāti, kuri pieder sekojošām identificētām sugām: Leuconostoc citreum Leuconostoc mesentoides, Lactobacillus buchneri, Lactobac…

Genomic conflicts and sexual antagonism in human health: Insights from oxytocin and testosterone

2015

We review the hypothesized and observed effects of two of the major forms of genomic conflicts, genomic imprinting and sexual antagonism, on human health. We focus on phenotypes mediated by peptide and steroid hormones (especially oxytocin and testosterone) because such hormones centrally mediate patterns of physical and behavioral resource allocation that underlie both forms of conflict. In early development, a suite of imprinted genes modulates the human oxytocinergic system as predicted from theory, with paternally inherited gene expression associated with higher oxytocin production, and increased solicitation to mothers by infants. This system is predicted to impact health through the i…

Evolutionary conflicts in a small mammal : behavioural, physiological and genetic differences between the sexes

2011

Getting the Fat out of Met and Fas

2008

Lack of Fas antagonism by Met in human fatty liver disease. Zou C, Ma J, Wang X, Guo L, Zhu Z, Stoops J, Eaker AE, Johnson CJ, Strom S, Michalopoulos GK, DeFrances MC, Zarnegar R. Hepatocytes in fatty livers are hypersensitive to apoptosis and undergo escalated apoptotic activity via death receptor-mediated pathways, particularly that of Fas–FasL, causing hepatic injury that can eventually proceed to cirrhosis and end-stage liver disease. Here we report that the hepatocyte growth factor receptor, Met, plays an important part in preventing Fas-mediated apoptosis of hepatocytes by sequestering Fas. We also show that Fas antagonism by Met is abrogated in human fatty liver disease (FLD). Throug…