| antifungal activity of venenatine, an indole alkaloid isolated from alstonia venenata. | the indole alkaloid venenatine exhibited antifungal activity against some plant pathogenic and saprophytic fungi. venenatine in an aqueous acetic acid solution inhibited spore germination of all the 10 tested fungi, fusarium udum, alternaria brassicicola, ustilago cynodontis and aspergillus flavus showed an especially high sensitivity towards this compound, exhibiting germination levels below 10%. the spore germination and colony development of the parasitic fungus erysiphe pisi, which causes po ... | 2000 | 11271828 |
| effect of calcium and calmodulin modulators on the development of erysiphe pisi on pea leaves. | the effect of calcium and calmodulin modulators, viz., ethylene glycol bis (beta-amino ethyl ether)-n,n,n',n'-tetraacetic acid (egta), a calcium chelator; verapamil, a plasma membrane ca2+ channel blocker; ruthenium red, an organelle ca2+ channel blocker; and chlorpromazine, a calmodulin antagonist; on the development of erysiphe pisi was studied by floating the inoculated leaves on the respective solutions of chemicals. all the modulators affected the development of e. pisi by inhibiting the co ... | 2001 | 11372655 |
| plant growth-promoting rhizobacteria-mediated induction of phenolics in pea ( pisum sativum) after infection with erysiphe pisi. | qualitative and quantitative estimation of phenolic compounds was done through high performance liquid chromatography (hplc) in different parts of pea ( pisum sativum) after treatment with two plant growth-promoting rhizobacteria (pgpr), viz., pseudomonas fluorescens (strain pf4) and pseudomonas aeruginosa (referred to here as pag) and infection by erysiphe pisi. the phenolic compounds detected were tannic, gallic, ferulic, and cinnamic acids on the basis of their retention time in hplc. in all ... | 2002 | 12000988 |
| effect of berberine and (+/-)-bicuculline isolated from corydalis chaerophylla on spore germination of some fungi. | berberine and (+/-)-bicuculline were isolated from roots and leaves, respectively, of corydalis chaerophylla. both were effective in vitro against spore germination of some plant pathogenic fungi (alternaria brassicicola, a. brassicae, a. cheiranthi, a. melongenae, a. solani, colletotrichum musae, c. falcatum, curvularia penniseti, c. lunata, c. maculans, c. pallescens, curvularia sp., erysiphe pisi, e. cichoracearum, erysiphe sp., fusarium udum, helminthosporium spiciferum, h. penniseti, h. fru ... | 2002 | 12058395 |
| actin-related defense mechanism to reject penetration attempt by a non-pathogen is maintained in tobacco by-2 cells. | the actin cytoskeleton is a key player in defense responses during early stages of infection by fungal pathogens. to investigate molecular mechanisms of actin-related defense responses, a cultured tobacco ( nicotiana tabacum l.) by-2 cell system was devised. when conidia were directly deposited on by-2 cells, neither a pathogen, erysiphe cichoracearum, nor a non-pathogen, erysiphe pisi, was able to form appressoria or haustoria on by-2 cells. on the other hand, conidia of the powdery mildews for ... | 2003 | 12728320 |
| what do microbes encounter at the plant surface? chemical composition of pea leaf cuticular waxes. | in the cuticular wax mixtures from leaves of pea (pisum sativum) cv avanta, cv lincoln, and cv maiperle, more than 70 individual compounds were identified. the adaxial wax was characterized by very high amounts of primary alcohols (71%), while the abaxial wax consisted mainly of alkanes (73%). an aqueous adhesive of gum arabic was employed to selectively sample the epicuticular wax layer on pea leaves and hence to analyze the composition of epicuticular crystals exposed at the outermost surface ... | 2005 | 16113231 |
| arabidopsis pen3/pdr8, an atp binding cassette transporter, contributes to nonhost resistance to inappropriate pathogens that enter by direct penetration. | arabidopsis thaliana is a host to the powdery mildew erysiphe cichoracearum and nonhost to blumeria graminis f. sp hordei, the powdery mildew pathogenic on barley (hordeum vulgare). screening for arabidopsis mutants deficient in resistance to barley powdery mildew identified penetration3 (pen3). pen3 plants permitted both increased invasion into epidermal cells and initiation of hyphae by b. g. hordei, suggesting that pen3 contributes to defenses at the cell wall and intracellularly. pen3 mutant ... | 2006 | 16473969 |
| a proteomic approach to study pea (pisum sativum) responses to powdery mildew (erysiphe pisi). | as a global approach to gain a better understanding of the mechanisms involved in pea resistance to erysiphe pisi, changes in the leaf proteome of two pea genotypes differing in their resistance phenotype were analyzed by a combination of 2-de and maldi-tof/tof ms. leaf proteins from control non-inoculated and inoculated susceptible (messire) and resistant (ji2480) plants were resolved by 2-de, with ief in the 5-8 ph range and sds-page on 12% gels. cbb-stained gels revealed the existence of quan ... | 2006 | 16511815 |
| microsatellite markers for powdery mildew resistance in pea (pisum sativum l.). | powdery mildew is a common disease of field pea, pisum sativum l., and is caused by the ascomycete fungus erysiphe pisi. it can cause severe damage in areas where pea is cultivated. today breeders want to develop new pea lines that are resistant to the disease. to make the breeding process more efficient, it is desirable to find genetic markers for use in a marker-assisted selection (mas) strategy. in this study, microsatellites (ssr) were used to find markers linked to powdery mildew resistance ... | 2005 | 16970617 |
| barley mlo modulates actin-dependent and actin-independent antifungal defense pathways at the cell periphery. | cell polarization is a crucial process during plant development, as well as in plant-microbe interactions, and is frequently associated with extensive cytoskeletal rearrangements. in interactions of plants with inappropriate fungal pathogens (so-called non-host interactions), the actin cytoskeleton is thought to contribute to the establishment of effective barriers at the cell periphery against fungal ingress. here, we impeded actin cytoskeleton function in various types of disease resistance us ... | 2007 | 17449647 |
| genetic dissection of resistance to anthracnose and powdery mildew in medicago truncatula. | medicago truncatula was used to characterize resistance to anthracnose and powdery mildew caused by colletotrichum trifolii and erysiphe pisi, respectively. two isolates of e. pisi (ep-p from pea and ep-a from alfalfa) and two races of c. trifolii (races 1 and 2) were used in this study. the a17 genotype was resistant and displayed a hypersensitive response after inoculation with either pathogen, while lines f83005.5 and dza315.16 were susceptible to anthracnose and powdery mildew, respectively. ... | 2008 | 18052883 |
| characterization of resistance mechanisms to erysiphe pisi in medicago truncatula. | abstract in this work, we studied the resistance of 277 medicago truncatula accessions against powdery mildew and further characterized the defense mechanisms of resistant plants. ten resistant accessions were selected according to macroscopic assessment. histological studies showed a range of defense mechanisms, acting alone or combined, that impeded fungal development at different stages. some accessions allowed a reduced spore germination frequency compared with that of the susceptible contro ... | 2007 | 18944169 |
| tryptophan-derived secondary metabolites in arabidopsis thaliana confer non-host resistance to necrotrophic plectosphaerella cucumerina fungi. | a defence pathway contributing to non-host resistance to biotrophic fungi in arabidopsis involves the synthesis and targeted delivery of the tryptophan (trp)-derived metabolites indol glucosinolates (igs) and camalexin at pathogen contact sites. we have examined whether these metabolites are also rate-limiting for colonization by necrotrophic fungi. inoculation of arabidopsis with adapted or non-adapted isolates of the ascomycete plectosphaerella cucumerina triggers the accumulation of trp-deriv ... | 2010 | 20408997 |
| molecular and cytological responses of medicago truncatula to erysiphe pisi. | summary powdery mildew is an economically important disease in a number of crop legumes; however, little is known about resistance to the disease in these species. to gain a better understanding of the genetics of resistance and plant responses to powdery mildew in legumes, we developed a pathosystem with medicago truncatula and erysiphe pisi. screening accessions of m. truncatula identified genotypes that are highly susceptible, moderately resistant and highly resistant to the fungus. in the hi ... | 2007 | 20507501 |
| linkage of a rapd marker with powdery mildew resistance. | the aim of this study was to investigate the inheritance of powdery mildew disease and to tag it with a dna marker to utilize for the marker-assisted selection (mas) breeding program. the powdery mildew resistant genotype fallon(er) and susceptible genotype 11760-3er were selected from 177 genotypes by heavy infestation of germplasm with erysiphe pisi through artificial inoculation. the f1 plants of the cross fallon/11760-3 indicated the dominance of the susceptible allele, while f2 plants segre ... | 2011 | 21539179 |
| expression of coordinately regulated defence response genes and analysis of their role in disease resistance in medicago truncatula. | microarray technology was used to identify the genes associated with disease defence responses in the model legume medicago truncatula. transcript profiles from m. truncatula cv. jemalong genotype a17 leaves inoculated with colletotrichum trifolii and erysiphe pisi and roots infected with phytophthora medicaginis were compared to identify the genes expressed in response to all three pathogens and genes unique to an interaction. the a17 genotype is resistant to c. trifolii and e. pisi, exhibiting ... | 2011 | 21726379 |