992 resultados para stored bean pest


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Breeding soybean for high seed quality is an important approach for developing cultivars for tropical regions, and the lignin content in the seed coat is one of the screening parameters for this trait. Considering that many breeding lines are evaluated in each growing season using the presently recommended method for lignin determination, a long period is required for the evaluation of the whole breeding program. This time limitation may influence lignin content assessment, if lignin is degraded during storage. This research reported was designed to determine whether lignin was degraded in the seed coat of soybean seed cultivars stored for one year in a controlled environment (10°C temperature and 50% air relative humidity). Seeds of 12 selected soybean cultivars that had a range in seed coat lignin content were evaluated. Seeds were hand harvested just after physiological maturity and evaluated for seed coat lignin content at harvest and after one year of storage in a cold room (10°C and 50% RH). The lignin content in seed coats differed significantly among cultivars in both analyses, but for both results the sequence of cultivar classification and the lignin content values of each cultivar did not change. A regression analysis of lignin content at harvest and after one year of storage indicated a direct relationship between both lignin determinations suggesting no differences between the lignin content of each cultivar due to prolonged storage (r² = 0.98***). This indicates that the lignin determination in the soybean seed coat can be performed over a long time period without any bias due to change in its content.

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Castor bean cropping has great social and economic value, but its production has been affected by factors such as low quality seeds used for sowing. The quick and precise evaluation of seed quality by x-ray test is known as an effective method to evaluate seed lots, but little is known about the interpretation between of the type of radiographic image and the seed quality correlation. The potential of x-ray analysis as a marker of seed physiological quality and as an initial process for the implementation of the use of computer-assisted image analysis was investigated using castor bean seeds of the different cultivars. The seeds were classified according to internal morphology visualized in the radiography and subjected to the germination test, emergency and seedling growth rate. It was possible to identify the different types of internal tissues, morphological and physical damage in castor bean seeds using the x-ray test. Tissues generating translucent images, embryo deformation, or tissues with less than 50% of endosperm reserves or spotted, negatively affected the physiological potential of the seed lots. Radiographic analysis is effective as an instrument to improve castor bean seed lot quality. This non destructive analysis allows the prediction of seedling performance and enabled the selection of high-quality seeds under the standards of a sustainable and precision agriculture

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Gliricidia sepium is a drought-tolerant species, easily multiplied by seeds, and has been exploited by farmers as a source of forage in the semi-arid region of northeast Brazil. The objective of the present study was to evaluate the effect of seed storage on the mobilization of reserves during imbibition of "Gliricidia" seeds. Freshly-harvested seeds were packed in kraft paper bags and stored for three and six months in the laboratory under ambient conditions (25 º C ± 3 T and 75% ± 3 RH). Cotyledons were isolated from imbibed seeds and macerated for the extraction and quantification of total soluble sugars, reducing sugars, sucrose and starch, as well as of proteins, amino acids and for amylase activity. Storage under these conditions resulted in an increase in seed water content although germination remained at relatively high levels (86%). Seed macromolecule levels showed significant variation with the storage period and imbibition and these variations were associated with a loss in seed viability due to inadequate storage conditions.

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The effect of chemical and biological treatments on castor bean emergence, seedling vigor, dry matter production, and also the control of microorganisms associated with seeds of the AL Guarany 2002 and Lyra cultivars, was evaluated. The products tested were carbendazim + thiram, carboxin + thiram and a product based on Trichoderma. Total seed and seedling emergence were evaluated at 27 days after sowing whereas dry matter production was verified for plants removed 45 days after sowing. The Guarany 2002 AL cultivar had a higher incidence of microorganisms than the Lyra cultivar. The chemical treatment was 100% effective in controlling fungi but the biological treatment did not reduce microorganism incidence on the seeds. Chemical treatment resulted in plants with more dry matter and the best results were for carbendazim + thiram and carboxin + thiram at doses of 60 g + 140 g and 50 g + 50 g/100 kg of seeds, respectively. The carbendazim + thiram mixture was the only treatment which was statistically higher for total emergence whereas the biological treatment increased emergence only for the Lyra cultivar, thus demonstrating its lower efficiency. The importance of fungicides to control pathogens associated with seeds was discussed.

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Xylopia aromatica is a native species from Brazil's "Cerrado", recommended for restoration ecology and also as a medicine. Its seeds have embryos with morphophysiological dormancy, making nursery propagation difficult. The objective of this study was to verify the efficiency of X-ray and tetrazolium tests for evaluating the viability of three seed lots, stored for different periods. All seeds were X-rayed (13 kV, 350 seconds) and samples used for tetrazolium and germination tests. In the tetrazolium test, seeds were submitted to six treatments at two temperatures (25 and 30 °C) with imbibition in distilled water and immersion in three concentrations of tetrazolium solution (0.5, 0.75 and 1%) at the two imbibition temperatures. Seeds for the germination test were placed for imbibition in distilled water and a 500 ppm Promalin® (6-Benzyladenine + GA4 + GA7) solution and later sown in sterilized sand. The embryo could not be observed with the X-ray test. However, those seeds observed with an undamaged endosperm did not differ in the percentages of seeds with firm and stained endosperms observed in the tetrazolium test for all the lots. The tetrazolium test is efficient for evaluating seed viability, principally if imbibed at 30 °C and immersed in a 0.5% solution at 30 °C.

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Castor bean fruits are already used for biodiesel production but obtaining quality seeds is still a challenge. Seed cleaning improves lot quality but little is known about the effects of upgrading castor bean seed lots on a densimetric table. The objective of this study was to evaluate the influence of cleaning castor bean seed lots on a densimetric table on their physical, physiological and sanitary characteristics. Two commercial lots of the AL Guarani 2002 cultivar, separated into five categories according to their classification on a densimetric table (uncleaned and low, low intermediate, high intermediate and high outlets), were evaluated. Tests for the yield, one-thousand seed weight, germination, seedling emergence, electrical conductivity and seed health were performed. The classification of castor bean seeds on a densimetric table significantly improved the physical, physiological and sanitary quality of commercial seed lots. The physiological response of the different classified lots varied according to their initial weight. Castor bean seeds separated on a densimetric table for the upper outlet showed a better physical, physiological and sanitary quality compared to those for the lower outlet.

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The soil-inhabiting insect-pathogenic fungus Metarhizium robertsii also colonizes plant roots endophytically, thus showing potential as a plant symbiont. M robertsii is not randomly distributed in soils but preferentially associates with the plant rhizosphere when applied in agricultural settings. Root surface and endophytic colonization of switchgrass (Panicum virgatum) and haricot beans (Phaseolus vulgaris) by M robertsii were examined after inoculation with fungal conidia. Light and confocal microscopies were used to ascertain this rhizosphere association. Root lengths, root hair density and emergence of lateral roots were also measured. Initially, M robertsii conidia adhered to, germinated on, and colonized, roots. Furthermore, plant roots treated with Metarhizium grew faster and the density of plant root hairs increased when compared with control plants. The onset of plant root hair proliferation was initiated before germination of M robertsii on the root (within 1-2 days). Plants inoculated with M robertsii AMAD2 (plant adhesin gene) took significantly longer to show root hair proliferation than the wild type. Cell free extracts of M robertsii did not stimulate root hair proliferation. Longer term (60 days) associations showed that M robertsii endophytically colonized individual cortical cells within bean roots. Metarhizium appeared as an amorphous mycelial aggregate within root cortical cells as well as between the intercellular spaces with no apparent damage to the plant. These results suggested that not only is M robertsii rhizosphere competent but displays a beneficial endophytic association with plant roots that results in the proliferation of root hairs. The biocontrol of bean (Phaseolis vulgaris) root rot fungus Fusarium solani f. sp. phaseolis by Metarhizium robertsii was investigated in vitro and in vivo. Dual cultures on Petri dishes showed antagonism of M robertsii against F. solani. A relative inhibition of ca. 60% of F. solani growth was observed in these assays. Cell free culture filtrates of M robertsii inhibited the germination of F. solani conidia by 83% and the inhibitory metabolite was heat stable. Beans plants colonized by M robertsii then exposed to F. solani showed healthier plant profiles and lower disease indices compared to plants not colonized by M robertsii. These results suggested that the insect pathogenic/endophytic fungus M robertsii could also be utilized as a biocontrol agent against certain plant pathogens occurring in the rhizosphere.

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Intercropping systems are seen as advantageous as they can provide higher crop yield and diversity along with fewer issues related to pests and weeds than monocultures. However, plant interactions in intercropped crop species and between crops and weeds in these systems are still not well understood. The main objective of this study was to investigate interactions between onion (Allium cepa) and yellow wax bean (Phaseolus vulgaris) in monocultures and intercropping with and without the presence of a weed species, either Chenopodium album or Amaranthus hybridus. Another objective of this study was to compare morphological traits of C. album from two different populations (conventional vs. organic farms). Using a factorial randomized block design, both crop species were planted either in monoculture or intercropped with or without the presence of one of the two weeds. The results showed that intercropping onion with yellow wax bean increased the growth of onion but decreased the growth of yellow wax bean when compared to monocultures. The relative yield total (RYT) value was 1.3. Individual aboveground dry weight of both weed species under intercropping was reduced about 5 times when compared to the control. The poor growth of weeds in intercropping might suggest that crop diversification can help resist weed infestations. A common garden experiment indicated that C. album plants from the conventional farm had larger leaf area and were taller than those from the organic farm. This might be associated with specific evolutionary adaptation of weeds to different farming practices. These findings contribute to the fundamental knowledge of crop-crop interactions, crop-weed competition and adaptation of weeds to various conditions. They provide insights for the management of diversified cropping systems and integrated weed management as practices in sustainable agriculture.

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Dans cette étude, la stabilité de préparations intraveineuses de cyclosporine (0.2 et 2.5 mg/mL dans NaCl 0.9% ou dextrose 5%) entreposées dans des seringues de polypropylène, des sacs de polypropylène-polyoléfine et des sacs de vinyle acétate d’éthylène a été évaluée. Une méthode HPLC indicatrice de la stabilité à base de méthanol a été développée et validée suite a des études de dégradation forcée. Les solutions évaluées ont été préparées de façon aseptique, puis entreposées à 25°C. La stabilité chimique a été évaluée par HPLC et la stabilité physique a été évaluée par inspection visuelle et aussi par diffusion dynamique de la lumière (DLS). Tous les échantillons sont demeurés stables chimiquement et physiquement dans des sacs de polypropylène-polyoléfine (>98% de cyclosporine récupérée après 14 jours). Lorsqu’entreposés dans des seringues de polypropylène, des contaminants ont été extraits des composantes de la seringue. Toutefois, aucune contamination n’a été observée après 10 min de contact entre la préparation de cyclosporine non-diluée et ces mêmes seringues. Les préparations de 2.5 mg/mL entreposées dans des sacs de vinyle acétate d’éthylène sont demeurés stables chimiquement et physiquement (>98% de cyclosporine récupérée après 14 jours). Toutefois, une adsorption significative a été observée avec les échantillons 0.2 mg/mL entreposés dans des sacs de vinyle acétate d’éthylène (<90% de cyclosporine récupéré après 14 jours). Une étude cinétique a démontré une bonne corrélation linéaire entre la quantité adsorbée et la racine carrée du temps de contact (r2 > 0.97). Un nouveou modèle de diffusion a été établi. En conclusion, les sacs de polypropylène-polyoléfine sont le meilleur choix; les seringues de polypropylène présentent un risque de contamination, mais sont acceptables pour un transfert rapide. Les sacs de vinyle acétate d’éthylène ne peuvent être recommandés à cause d’un problème d’adsorption.

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Frozen storage characteristics and shelflife vary considerably among species as well as within the species (Powrie, 1973; Fennema. 1973). This can be attributed to the variation in the composition of fish among various species. In certain species like sardines and mackerel. wide seasonal variation in chemical composition occur within the species. These variations affect the quality and shelflife. The nutritional level of water. spawning, method of catching, struggling etc. are found to have profound influence on the condition of the fresh fish. Soon after death the deteriorative changes in fish start due to autolysis and bacterial growth. The rate of these changes depends mainly on temperature. The handling methods have great influence on bacterial contamination. Thus the type oi'handling. temperature control. period of chill storage. processing methods. type of freezing, condition of frozen storage and period of storage affect the quality and shelflife Of the fisho In the present study extensive investigations were carried out on various factors affecting the quality of fish as well as their effect on the physical. chemical and sensory qualities of fish during frozen storage and the shelflife

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Das Ziel dieser Arbeit war, die Einflüsse von Wurzeln und Rhizodeposition auf den Umsatz von Körnerleguminosenresiduen und damit verknüpfte mikrobielle Prozesse zu untersuchen. In einem integrierten Versuch wurden Ackerbohne (Vicia faba L.), Erbse (Pisum sativum L.) und Weiße Lupine (Lupinus albus L.) untersucht. Der Versuch bestand aus drei Teilen, zwei Gefäß-Experimenten und einem Inkubationsexperiment, in denen ausgehend von einem Gefäß-Experiment derselbe Boden und dasselbe Pflanzenmaterial verwendet wurden. In Experiment I wurde die Stickstoff-Rhizodeposition der Körnerleguminosenarten, definiert als wurzelbürtiger N nach dem Entfernen aller sichtbaren Wurzeln im Boden, gemessen und der Verbleib des Rhizodepositions-N in verschiednenen Bodenpools untersucht. Dazu wurden die Leguminosen in einem Gefäßversuch unter Verwendung einer in situ 15N-Docht-Methode mit einer 15N Harnstofflösung pulsmarkiert. In Experiment II wurde der Umsatz der N-Rhizodeposition der Körnerleguminosen und der Einfluss der Rhizodeposition auf den anschließenden C- und N-Umsatz der Körnerleguminosenresiduen in einem Inkubationsexperiment untersucht. In Experiment III wurde der N-Transfer aus den Körnerleguminosenresiduen einschließlich N-Rhizodeposition in die mikrobielle Biomasse und die Folgefrüchte Weizen (Triticum aestivum L.) und Raps (Brassica napus L.) in einem Gewächshaus-Gefäßversuch ermittelt. Die in situ 15N Docht-Markierungs-Methode wies hohe 15N Wiederfindungsraten von ungefähr 84 Prozent für alle drei Leguminosenarten auf und zeigte eine vergleichsweise homogene 15N Verteilung zwischen verschiedenen Pflanzenteilen zur Reife. Die Wurzeln zeigten deutliche Effekte auf die N-Dynamik nach dem Anbau von Körnerleguminosen. Die Effekte konnten auf die N-Rhizodeposition und deren anschließenden Umsatz, Einflüsse der Rhizodeposition von Körnerleguminosen auf den anschließenden Umsatz ihrer Residuen (Stängel, Blätter, erfassbare Wurzeln) und die Wirkungen nachfolgender Nichtleguminosen auf den Umsatzprozess der Residuen zurückgeführt werden: Die N-Rhizodeposition betrug zur Reife der Pflanzen bezogen auf die Gesamt-N- Aufnahme 13 Prozent bei Ackerbohne und Erbse und 16 Prozent bei Weißer Lupine. Bezogen auf den Residual N nach Ernte der Körner erhöhte sich der relative Anteil auf 35 - 44 Prozent. Die N-Rhizodeposition ist daher ein wesentlicher Pool für die N-Bilanz von Körnerleguminosen und trägt wesentlich zur Erklärung positiver Fruchtfolgeeffekte nach Körnerleguminosen bei. 7 - 21 Prozent des Rhizodepositions-N wurden als Feinwurzeln nach Nasssiebung (200 µm) wiedergefunden. Nur 14 - 18 Prozent des Rhizodepositions-N wurde in der mikrobiellen Biomasse und ein sehr kleiner Anteil von 3 - 7 Prozent in der mineralischen N Fraktion gefunden. 48 bis 72 Prozent der N-Rhizodeposition konnte in keinem der untersuchten Pools nachgewiesen werden. Dieser Teil dürfte als mikrobielle Residualmasse immobilisiert worden sein. Nach 168 Tagen Inkubation wurden 21 bis 27 Prozent des Rhizodepositions-N in den mineralisiert. Der mineralisierte N stammte im wesentlichen aus zwei Pools: Zwischen 30 Prozent und 55 Prozent wurde aus der mikrobiellen Residualmasse mineralisiert und eine kleinere Menge stammte aus der mikrobielle Biomasse. Der Einfluss der Rhizodeposition auf den Umsatz der Residuen war indifferent. Durch Rhizodeposition wurde die C Mineralisierung der Leguminosenresiduen nur in der Lupinenvariante erhöht, wobei der mikrobielle N und die Bildung von mikrobieller Residualmasse aus den Leguminosenresiduen in allen Varianten durch Rhizodepositionseinflüsse erhöht waren. Das Potential des residualen Körnerleguminosen-N für die N Ernährung von Folgefrüchten war gering. Nur 8 - 12 Prozent des residualen N wurden in den Folgenfrüchten Weizen und Raps wiedergefunden. Durch die Berücksichtigung des Rhizodepositions-N war der relative Anteil des Residual-N bezogen auf die Gesamt-N-Aufnahme der Folgefrucht hoch und betrug zwischen 18 und 46 Prozent. Dies lässt auf einen höheren N-Beitrag der Körnerleguminosen schließen als bisher angenommen wurde. Die residuale N-Aufnahme von Weizen von der Blüte bis zur Reife wurde durch den Residual-N gespeist, der zur Blüte in der mikrobiellen Biomasse immobilisiert worden war. Die gesamte Poolgröße, Residual-N in der mikrobiellen Biomasse und in Weizen, veränderte sich von der Blüte bis zur Reife nicht. Jedoch konnte ein Rest von 80 Prozent des Residual-N in keinem der untersuchten Pools nachgewiesen werden und dürfte als mikrobielle Residualmasse immobilisiert worden sein oder ist noch nicht abgebaut worden. Die zwei unterschiedlichen Folgefrüchte - Weizen und Raps - zeigten sehr ähnliche Muster bei der N-Aufnahme, der Residual-N Wiederfindung und bei mikrobiellen Parametern für die Residuen der drei Körnerleguminosenarten. Ein differenzierender Effekt auf den Umsatz der Residuen bzw. auf das Residual-N-Aneignungsvermögen der Folgefrüchte konnte nicht beobachtet werden.

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Little is known about gaseous carbon (C) and nitrogen (N) emissions from traditional terrace agriculture in irrigated high mountain agroecosystems of the subtropics. In an effort towards filling this knowledge gap measurements of carbon dioxide (CO_2), methane (CH_4), ammonia (NH_3) and dinitrous oxide (N_2O) were taken with a mobile photoacoustic infrared multi-gas monitor on manure-filled PE-fibre storage bags and on flood-irrigated untilled and tilled fields in three mountain oases of the northen Omani Al Jabal al Akhdar mountains. During typical 9-11 day irrigation cycles of March, August and September 2006 soil volumetric moisture contents of fields dominated by fodder wheat, barley, oats and pomegranate ranged from 46-23%. While manure incorporation after application effectively reduced gaseous N losses, prolonged storage of manure in heaps or in PE-fibre bags caused large losses of C and N. Given the large irrigation-related turnover of organic C, sustainable agricultural productivity of oasis agriculture in Oman seems to require the integration of livestock which allows for several applications of manure per year at individual rates of 20 t dry matter ha^−1.

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Seed moisture content is significant in the handling and processing of seeds. This work therefore determined the physical properties of Locust bean seeds as functions of seed moisture content in the moisture range of 5.9 – 28.2% dry basis. Mohsenin, Stepanoff and ASAE standard methods were used in determining the properties. Increases in seed dimensions vitz length = 10.2±1.0 – 11.3±0.9 mm; width = 8.5±0.8 – 9.1±0.6 mm; surface area = 191.2±24.6 – 208.3±26.3 mm2 ; geometric mean diameter = 7.78±0.49 – 8.12±0.03 and arithmetic mean diameter = 8.06±0.56 – 8.34±0.49 mm were recorded. Seed thickness = 5.49±0.43 – 5.26±0.62 mm; sphericity = 0.75±0.04 – 0.71±0.03; true density = 1251.96±55.5 - 1222±62.16 kgm-3 and porosity = 48.4±2.14 – 41.9±3.78 decreased. Static coefficient of friction increased on plywood (0.5±0.02 – 0.6±0.01), glass (0.4±0.05 – 0.5±0.01) and decreased on aluminium (0.5±0.02 – 0.5±0.04). A data of the physical properties of Locust bean; Parkia biglobosa was developed. This is useful for the design and development of equipment necessary for its handling and processing.

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The females of the bluemouth rockfish, Helicolenus dactylopterus dactylopterus (DelaRoche, 1809), store sperm within their ovaries for periods of up to 10 months. Twenty six females with standard lengths between 152 and 257 mm and six males with standard lengths between 253 and 209 mm were caught storage crypts with stored spermatozoa and to describe their evolution over the year. After internal fertilization and once sperm reaches the ovary, a crypt forms probably by an epithelial inclusion at the base of the lamellae of one or several spermatozoa groups that are floating freely in the interlamellar space of the ovarian lumen. Stored spermatozoa have a large cytoplasm bag surrounding their heads. This bag could serve as a nutritive reservoir during the long storage period. Many desmosonal and tight junctions between the crypt cells ensure tha male sex cells are protected against the female immune system

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Mamá y papá tienen que ausentarse de casa durante unos días, pero entonces alguien se tiene que ocupar de Clarice y de sus hermanos, Marcie, Minal y Kurt y del abuelo. Como último recurso, mamá pide al tío Ted que haga de canguro. Tras unos días de normalidad en la casa, se hace el caos.