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Xiujuan Wang Amélie MathieuPaul-Henry Cournède Jean-Michel AllirandAlexandra Jullien Philippe de ReffyeBao Gui Zhang 《Field Crops Research》2011,122(1):60-69
The number of pods per plant and the number of seeds per pod are the most variable yield components in winter oilseed rape (WOSR). Both the number of ovules per pod and the potential for the ovule to develop into a mature seed may depend on pod position in the plant architecture and time of appearance. The complex developmental pattern of WOSR makes it difficult to analyse. The objectives of this study were to investigate the variability of the following yield components (a) ovules/pod, (b) seeds/pod, and (c) pods/axis in relation to two explanatory variables. These two variables include (1) flower and inflorescence position and (2) time of pod appearance, linked to the effect of assimilate availability.Field experiments were conducted with the variety Mendel. Different trophic states were created by clipping the main stem or ramifications. The number and position of flowers that bloomed within the inflorescence were recorded based on observations every two to three days throughout the flowering season.On the control plants, for the main stem we observed that the number of ovules per pod decreased for a few ranks and then tended to increase and again to decrease at the end. On ramification R1 and R4, the number of ovules increased at first, and then remained constant with the pod rank. Furthermore, the number of ovules per pod remained constant along the inflorescence on the other ramifications and increased with ramifications from top to bottom. The number of seeds per pod did not vary with the pod rank at the basal positions on inflorescences and decreased afterwards along the inflorescence. The clipping of the main stem or ramifications increased the number of ovules per pod, seeds per pod and pods per axis. The number of ovules and seeds per pod did not vary with the time of pod appearance for the pods located at normalised rank 0.01-0.1. However, the number of ovules and seeds per pod can be impacted by the time of pod appearance on the plant scale. Thus, our results indicate that the amount of available assimilates was the primary determinant of pod and seed production during the flowering period. The distribution of resources was significantly affected by both the positions of pods within an inflorescence and the position of inflorescences within a plant. 相似文献
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Laure Weisskopf Renée-Claire Le Bayon Florian Kohler Valérie Page Maryline Jossi Jean-Michel Gobat Enrico Martinoia Michel Aragno 《Soil biology & biochemistry》2008,40(7):1772-1780
Plants are generally assumed to influence the surrounding soil microflora through rhizodeposition. However, the role of rhizodeposits, and especially organic acids, in structuring the bacterial communities is still poorly understood. In this study, we asked the question whether plants differing in organic acid secretion have a different impact on the soil bacterial communities, and if this is the case, to which extent this impact is due to different organic acid concentrations in the rhizosphere. To investigate this question, we compared white lupin and wheat. The former is a high organic acid-secreting species, while the latter secretes only low amounts of carboxylates. We grew the plants in large microcosms including root-free control compartments for one year (replanted every second month) and analyzed the spatio-temporal changes in soil ATP concentrations, as well as in diversity and structure of bacterial communities (using DNA- and RNA-based DGGE) along a root-soil gradient after two, six and twelve month's cultivation. Our results showed: i) that white lupin and wheat differed in their impact on soil ATP concentrations and on the structure of root bacterial communities; ii) that cultivation time was a key factor in explaining the observed differences in all the parameters studied; and iii) that the amounts of organic acids accounted for a significant proportion (15%) of the variability within root active communities. These results indicate that plants influence their associated bacterial communities in a species-specific way and that for communities living in the direct vicinity of roots (rhizoplane-endorhizosphere), a significant part of this influence can be attributed to root-secreted organic acids. 相似文献
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Pierre Roudier Bruno Tisseyre Hervé Poilvé Jean-Michel Roger 《Precision Agriculture》2008,9(5):233-250
Site-specific management (SSM) is a common way to manage within-field variability. This concept divides fields into site-specific
management zones (SSMZ) according to one or several soil or crop characteristics. This paper proposes an original methodology
for SSMZ delineation which is able to manage different kinds of crop and/or soil images using a powerful segmentation tool:
the watershed algorithm. This image analysis algorithm was adapted to the specific constraints of precision agriculture. The
algorithm was tested on high-resolution bio-physical images of a set of fields in France. 相似文献
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Hily Jean-Michel Komar Véronique Poulicard Nils Velt Amandine Renault Lauriane Mustin Pierre Vigne Emmanuelle Spilmont Anne-Sophie Lemaire Olivier 《European journal of plant pathology / European Foundation for Plant Pathology》2021,161(3):735-742
European Journal of Plant Pathology - Since its identification in 2003, grapevine Pinot gris virus (GPGV, Trichovirus) has now been detected in most grape-growing countries. So far, little is known... 相似文献
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This report describes a case of Mycobacterium tuberculosis infection in a green-winged macaw (Ara chloroptera), confirmed by microbiologic and pathologic diagnostics, and notes a possible human-avian transmission. Clinical signs included cutaneous swellings, profound leukocytosis, and signs of osteomyelitis in the long bones. Proliferation consisted of several nodules with small greenish-caseous foci in cross-section and revealed a severe granulomatous inflammation with intralesional acid-fast rods. Mycobacterium tuberculosis was isolated from subcutaneous nodules and biochemically confirmed. The disease in avian species is of zoonotic importance. 相似文献
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Vitrac X Bornet A Vanderlinde R Valls J Richard T Delaunay JC Mérillon JM Teissédre PL 《Journal of agricultural and food chemistry》2005,53(14):5664-5669
Phenolics from grapes and wines can play a role against oxidation and development of atherosclerosis. Stilbenes have been shown to protect lipoproteins from oxidative damage and to have cancer chemopreventive activity. We describe a method for the direct determination of stilbenes in several red wines using high-performance liquid chromatography with UV detection. In a survey of 12 commercial wines from the south of Brazil (Rio Grande del Sul), levels of delta-viniferin are reported for the first time in different varieties of red wines. Brazilian red wine contains trans-astringin, trans-piceid, trans-resveratrol, cis-resveratrol (in high quantity: 5 times more than the trans form), epsilon-viniferin, and a compound isolated for the first time in wine, trans-delta-viniferin. Isolation and identification of delta-viniferin was achieved by NMR after extraction and fractionation of red wine phenolics. delta-Viniferin contributes, as well as cis-resveratrol and trans-piceid, to a significant proportion of stilbenes in wine dietary intake, particularly with Merlot varieties containing an average level of 10 mg/L for delta-viniferin, 15 mg/L for cis-resveratrol, and 13 mg/L for trans-piceid. The total stilbene intake from wine origin was estimated for the Brazilian population as 5.3 mg/day per person (on the basis of a regular wine consumption of 160 mL/day). delta-Viniferin can contribute to around 20% of total stilbenes in wine (average of 6.4 mg/L in red Brazilian wines). It would be important in the future to investigate the origins of the differences in wine stilbene levels in relation to the vine varieties, and the bioavailability of the newly extracted stilbene delta-viniferin in plasma after consumption of different types of wines. 相似文献