Search results for "Cotyledon"
showing 10 items of 21 documents
C3cotyledons are followed by C4leaves: intra-individual transcriptome analysis ofSalsola soda(Chenopodiaceae)
2016
The genome of Salsola soda allows a transition from C3 to C4 photosynthesis. A developmental transcriptome series revealed novel genes showing expression patterns similar to those encoding C4 proteins.
Biomechanics and functional morphology of a climbing monocot.
2015
Climbing monocots can develop into large bodied plants despite being confined by primary growth. In our study on Flagellaria indica we measured surprisingly high stem biomechanical properties (in bending and torsion) and we show that the lack of secondary growth is overcome by a combination of tissue maturation processes and attachment mode. This leads to higher densities of mechanically relevant tissues in the periphery of the stem and to the transition from self-supporting to climbing growth. The development of specialised attachment structures has probably underpinned the evolution of numerous other large bodied climbing monocot taxa.
Effects of Acifluorfen-methyl on cucumber cotyledons : porphyrin accumulation
1988
Abstract The nitrodiphenyl ether herbicide acifluorfen-methyl and the pyridine derivative LS 82-556 induce porphyrin accumulation in green cucumber cotyledons. When experiments are done with intact plants absorbing the herbicide through the roots, that accumulation is light-dependent. 3-(3,4-Dichlorophenyl)-1,1-dimethylurea (DCMU) which prevents cellular damages under these conditions (M. Matringe and R. Scalla, Pestic. Biochem. Physiol. 26 , 150 (1986), also inhibits porphyrin accumulation. In contrast, when detached cotyledons are cut into pieces and floated on herbicide solutions, porphyrins accumulate in the dark. Accordingly, DCMU does not inhibit porphyrin accumulation or protect the …
Faster acquisition of symbiotic partner by common mycorrhizal networks in early plant life stage
2016
Arbuscular mycorrhizal (AM) fungi usually improve plant performance yet our knowledge about their effects on seed germination and early plant establishment is very limited. We performed a factorial greenhouse experiment where the seeds from four low Arctic cooccurring mycorrhizal herbs (Antennaria dioica, Campanula rotundifolia, Sibbaldia procumbens, and Solidago virgaurea) were germinated alone or in the vicinity of an adult Sibbaldia plant with or without AM fungi; given either as spores or being present in a common mycorrhizal network (CMN). Three different AM fungal species were examined to assess species-specific differences in symbiont acquisition rate. Out of the four plant species i…
Which traits allow weed species to persist in grass margin strips ?
2017
EASPEGESTADINRA; Sown-grass margin strips, historically established to limit pesticide drift and soil erosion, are now also promoted for enhancing floral diversity and associated ecosystem services. To better understand weed community assembly in grass margin strips, we performed floral surveys in 75 sown-grass margin strips in two regions in France and characterized each species using information from trait databases. We hypothesized that traits of dominant species would differ between newly sown-grass margin strips and older strips. Weed species were separated into functional groups based on their traits using multiple correspondence analysis and hierarchical ascendant classification. Fun…
Regeneration of herbicide-tolerant black locust transgenic plants by SAAT
2003
A protocol based on SAAT (sonication-assisted Agrobacterium-mediated transformation) has been developed to obtain herbicide-resistant transgenic black locust (Robinia pseudoacacia L.) plants. Cotyledon explants were co-cultivated with Agrobacterium AGL1 strain carrying the pTAB16 plasmid (bar and gusA genes). The effects of bacterial concentration (OD550 of 0.3, 0.6, 0.8) and method of infection (sonication vs immersion) on bacterial delivery were determined by assaying cotyledons for transient beta-glucuronidase expression 3 days after infection. SAAT increases transient expression efficiency especially at an OD550 of 0.6. After determining bacterial concentration and infection method, oth…
Trois modes de production comparés en Bourgogne viticole. Indicateurs environnementaux, d'utilisation des produits phytos, d'état sanitaire de la vig…
2010
International audience; Un essai viticole de moyenne durée a été mis en place en Bourgogne en 2005 afin de comparer trois modes de production: viticulture de référence, viticulture biologique, viticulture « Ecophyto 2018 » (avec réduction d'intrants). Pour chaque mode de production, les principaux paramètres agronomiques quantitatifs et qualitatifs sur la plante et le sol sont déterminés. Les aspects environnementaux sont appréhendés à travers la biocénose du sol et des critères définis dans le cadre du Grenelle de l'Environnement (nombre de passages, quantités de substances actives, IFT). Les incidences économiques sont évaluées. Les premiers résultats montrentque leschoixd'itinéraire tech…
Versuche zur somatischen Beeinflussung der Organbildung pflanzlicher Embryonen
1955
Experiments on influencing cotyledon formation in embryos ofEranthis hiemalis are reported. By treating the seeds with 100–2000 ppm solutions of 2,4-dichlorophenoxyacetic acid, 2,4,5-trichlorophenoxyacetic acid, 2-methyl-4-chlorophenoxyacetic acid, α-naphthylacetic acid and even isopropyl N-phenyl carbamate one can obtain significant increases in twinning and in cotyledon anomalies (syncotyly and pleiocotyly of all degrees). Embryos can be successfully treated until approximately 2 weeks after initial opening of the follicles. X-radiations achieve the same effect, with doses of 2000–4000r corresponding to the treatments with 1000–2000 ppm 2,4-D-solutions. By using weaker concentrations and …
Comparison of iron acquisition from Fe–pyoverdine by strategy I and strategy II plants
2011
; Iron is an essential micronutrient for plants and associated microorganisms. However, the bioavailability of iron in cultivated soils islow. Plants and microorganisms have thus evolved active strategies of iron uptake. Two different iron uptake strategies have been described in dicotyledonous and monocotyledonous graminaceous species. In bacteria,this strat-egy relies on the synthesis of siderophores. Pyoverdines, a major class of siderophores produced byfluorescent pseudomo-nads, were previously shown topromote ironnutrition of the dicotyledonous species ArabidopsisthalianaL.(Heynh.), whereas contradictory reports were made on the contribution of those siderophores to the nutrition of g…
Forecasting the onset of an allergic risk to poaceae in Nancy and Strasbourg (France) with different methods
2008
International audience; Pollen of Poaceae is among the most allergenic pollen in Europe with pollen of birch. It is therefore useful to elaborate models to help pollen allergy sufferers. The objective of this study was to construct forecast models that could predict the first day characterized by a certain level of allergic risk called here the Starting Date of the Allergic Risk . Models result from four forecast methods (three summing and one multiple regression analysis) used in the literature. They were applied on Nancy and Strasbourg from 1988 to 2005 and were tested on 2006. Mean Absolute Error and Actual forecast abili ty test are the parameters used to choose best models, assess and …