Search results for " germination"
showing 10 items of 69 documents
Seeds vitality and fungal contamination in Abies nebrodensis
2022
Seeds of Abies nebrodensis were subjected to laboratory tests aimed to detect fungal contaminants and to obtain xenobiotic-free seedlings, by the use of different surface sterilising agents. Moreover, hot water at 60°C was used to suppress any fungal microorganisms colonizing the inner tissues. Alternaria alternata, Aspergillus flavus and Stemphylium vesicarium were the most frequent fungal contaminants. Non-contaminated seeds showed germination values ranging from 0 to 36.4% depending on the applied sterilization protocol. Further analyses will be carried out to establish the influence of these fungi on the seed germination process and their relationship with seedlings of A. nebrodensis.
Modeling the effect of ethanol vapor on the germination time of Penicillium chrysogenum.
2005
The influence of ethanol vapor on germination of Penicillium chrysogenum was determined on yeast nitrogen base plus glucose agar medium at 25 degrees C. Ethanol vapors were generated by 0 to 6% (wt/wt) ethanol solutions at the bottom of hermetically closed petri dishes. The logistic equation was used to describe the data as the percentage of germination versus time and to estimate the germination time. The effect of ethanol concentration on germination time was described by a new reparameterized equation, resulting in an estimated limiting ethanol concentration of 4.3%. Up to 3% ethanol, all spores germinated, and the germination time increased with increasing ethanol concentration. At 3.5 …
Prediction of conidial germination of Penicillium chrysogenum as influenced by temperature, water activity and pH.
2001
M. SAUTOUR, A. ROUGET, P. DANTIGNY, C. DIVIES AND M. BENSOUSSAN. 2001 Aims: Conidial germination of Penicillium chrysogenum was carried out under operating conditions compatible with a pastries manufacturing process. Methods and Results: A range, limited by two experimental values, was defined for each environmental factor tested: temperature (15 or 25°C), water activity (0·75 or 0·85) and pH (3·5 or 5·5). A closed device was made, which maintained an equilibrium between water activity of the culture medium and atmospheric relative humidity during 25 days, to follow spore germination. The combined effects of temperature, water activity and pH on spore germination were studied by applying fa…
Impact of water activity of diverse media on spore germination of Aspergillus and Penicillium species
2010
International audience; The effects of water activity (aw) of diverse media i/ culture medium for sporogenesis, aw sp ii/ liquid spore suspension medium, aw su and iii/ medium for germination, aw ge, on the germination time tG of Aspergillus carbonarius, Aspergillus flavus, Penicillium chrysogenum and Penicillium expansum were assessed according to a screening matrix at 0.95 and 0.99 aw. It was shown that i/ reduced tGs were obtained at 0.95 aw sp except for P. expansum ii/ a significant effect of aw su on tG was demonstrated for A. carbonarius, P. chrysogenum and P. expansum iii/ the most important factor for controlling the germination time was the medium for germination except for A. car…
Expression Patterns of Key Hormones Related to Pea (Pisum sativum L.) Embryo Physiological Maturity Shift in Response to Accelerated Growth Conditions
2019
Protocols have been proposed for rapid generation turnover of temperate legumes under conditions optimized for day-length, temperature, and light spectra. These conditions act to compress time to flowering and seed development across genotypes. In pea, we have previously demonstrated that embryos do not efficiently germinate without exogenous hormones until physiological maturity is reached at 18 days after pollination (DAP). Sugar metabolism and moisture content have been implicated in the modulation of embryo maturity. However, the role of hormones in regulating seed development is poorly described in legumes. To address this gap, we characterized hormonal profiles (IAA, chlorinated auxin…
Dissection of Genetic Cell Programmes Driving Early Arbuscular Mycorrhiza Interactions
2008
The persistence through evolution of the arbuscular mycorrhiza (AM) symbiosis between Glomeromycota and plants is probably due to a widespread molecular dialogue between the two partners. Most studies have focussed on established mycorrhizal systems whilst evidence for cellular commitment of the symbiotic partners during early developmental phases is recent. Whereas spore germination by AM fungi can occur spontaneously, subsequent hyphal branching, appressoria differentiation, root penetration and intraradical development leading to symbiosis establishment are under the control of molecular interactions between the two partners. In this chapter, recent work on AM fungus–plant interactions i…
Indicateurs pour l'évaluation de l'impact de produits phytosanitaires sur la composante microbienne de la qualité biologique des sols
2011
National audience
Différences de capacités d’induction de la germination de deux pathovars d’orobanche rameuse sur une gamme d’hôtes des familles des brassicacées et f…
2016
Branched broomrape (Phelipanche ramosa (L.) Pomel) is a holoparasite weed causing significant yield losses on several crops, especially in France on winter oilseed rape fields. The ability to induce germination of seeds of branched broomrape, variable between host species, represent an important information to identify the status of weed species present in the crop (host or non-host). In this study, conducted in in vitro conditions, we focused on two botanical families and two dominant pathovars of branched broomrape in France. We show that the host species is the only important explanatory factor of seed germination rate, the latter being not affected by the pathovar. Among the species stu…
Effect of analogues of plant growth regulators on in vitro growth of eukaryotic plant pathogens
2004
FGA (furfurylamine; 1,2,3,4 tetra-O-acetyl-β-d-glucose; adipic acid monoethyl ester), a chemical mixture of three analogues of plant growth regulators that increases the protection of tomato plants against phytopathogens, was demonstrated to have direct antimicrobial activity. It reduced the growth in vitro of the filamentous fungi Alternaria solani and Botrytis cinerea, and the oomycetes Phytophthora capsici and Phytophthora citrophthora (ED50 0·18–0·26% w/v, depending on species). The components of this mixture were also active against these phytopathogens, but sensitivity to the compounds was different for each pathogen. Adipic acid monoethyl ester (E) showed the highest and widest range…
Seed germination in the Sicilian subspecies ofDianthus rupicolaBiv. (Caryophyllaceae)
2012
Abstract Five populations belonging to three subspecies of Dianthus rupicola Biv. (D. rupicola subsp. rupicola, D. rupicola subsp. aeolicus, and D. rupicola subsp. lopadusanus) and growing in different geographical areas of Sicily were tested for seed germination at various temperatures. All populations showed high germination rates with an optimum temperature between 15°C and 25°C. Efficient seed germination might contribute significantly to the preservation of these subspecies which are currently exposed to several environmental threats.