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Showing 1 to 20 of 45 for “"helianthus"”.
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Estudio agroecológico de las malezas : Helianthus annuus y Helianthus petiolaris
El género Helianthus incluye especies silvestres y cultivadas de importancia biológica, genética y económica. Entre ellas, H. annuus y H. petiolaris se encuentran naturalizadas en la región Central Argentina. Ambas especies pueden comportarse como maleza, invadir lotes de producción de granos, …
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Sunflower, Helianthus annus L., Cut Flower Variety Trial
Sunflower, Helianthus annus L., native of North America, is widely grown for oil, bird feed, and human snacks. More recently, sunflower is gaining acceptance as an ornamental potted plant and as a cut flower in the florist industry. The objectives of the present study were: 1. To evaluate diverse …
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Economic Analysis of Sunflower (Helianthus annuus) Spacing in East Texas
… experiments were conducted on spacing of <em>Helianthus annuus</em> in East Texas to determine the spacing treatment that produces the greatest revenue per m<sup>2</sup>. The experiments had four spacing treatments of 8 × 15 cm, 15 × 15 cm, 23 × 23 cm, and 30 × 30 cm. Three different cultivars …
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Characterizing Low Nutrient Stress Resistance in Crop Sunflowers (Helianthus annus)
… this study, 60 different genetic sunflower (<em>Helianthus annuus</em>) lines were grown in the field under fertilized and unfertilized treatments to assess phenotypic traits associated with low nutrient stress resistance. Sunflowers were assessed for stress resistance using height, stem …
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MOLECULAR CHARACTERIZATION OF THE INTERACTION BETWEEN HELIANTHUS ANNUUS AND VERTICILLIUM DAHLIAE
Verticillium wilt, caused by the soil-borne Verticillium dahliae Klebahn is a serious problem in the production of sunflower worldwide. To date, information on sunflower resistance to Verticillium spp. is very scarce, although it is critical for an effective management of this pathogen. In this …
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An investigation of aspects of the nitrogen physiology of Helianthus annuus L
Helianthus annuus L. plants were grown hydroponically in Long Ashton nutrient solutions containing either 2 mM ammonium, 2 mM nitrate or 1 mM ammonium+ 1 mM nitrate as the nitrogen supply to determine the effect of these nutrients upon physiological processes within the plant. Nitrate fed plants …
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Increased phenotypic plasticity linked to broader geographic range size in sunflower (Helianthus) species
… fitness of broadleaf species like sunflowers (Helianthus spp.). In a garden experiment, we compared the phenotypic plasticity of five Helianthus species representing different geographic ranges. Locally restricted H. longifolius and H. verticillatus showed less plasticity in growth and …
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Pinching and Spacing Effects on Cut Sunflower (Helianthus annuus) Production in East Texas
… evaluated pinching and spacing on <em>Helianthus annuus </em>in East Texas to determine their effects on growth and development. Experiment 1 was designed to determine the effects of pinching nodes 1, 2, 3, or 4 on ‘Pro Cut Gold’ sunflowers. Results from experiment 1 showed non-pinched …
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Floral trait architecture in crop sunflower (<i>Helianthus annuus</i>) under drought conditions
… in oilseed crops such as sunflower (<em>Helianthus annuus</em>), but their susceptibility to drought stress is understudied. The goal of this study was to describe the floral trait architecture of <em>H. annuus</em> crop lines under drought versus well-watered conditions and examine the …
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Effects of Management and Population Size on Genetic Diversity of Eggert's Sunflower (HELIANTHUS EGGERTII; ASTERACEAE)
Helianthus eggertii (Asteraceae) is a federally threatened sunflower species that typically grows between open woods and barrens. This species has both sexual and asexual modes of reproduction, which can influence the amount of genetic diversity present within and among populations. Maintaining …
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Evaluasi ketahanan beberapa aksesi bunga matahari (Helianthus annus L.) terhadap ulat grayak (Spodoptera litura F.)
INDONESIA: Bunga matahari (Helianthus annus L.) merupakan salah satu tumbuhan yang berpotensi sebagai sumber penghasil minyak. Ulat grayak (Spodoptera litura F.) merupakan salah satu hama penting pada tanaman bunga matahari. Usaha pengendalian hama seringkali dilakukan dengan penyemprotan pestisida …
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Untersuchungen zum radialen Abscisinsäure- und Wassertransport in Wurzeln von Helianthus annuus L. und Zea mays L.
Mit den Experimenten dieser Arbeit konnte erstmals gezeigt werden, dass ein Phytohormon wie Abscisinsäure mit dem "Solvent-drag" des Wasserflusses apoplastisch durch den Wurzelzellwandbereich in die Xylemgefäße transportiert werden kann. Es konnte ein Bypass-Fluss für ABA durch den gesamten …
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The physiological effects of heat stress on anthesis and pollination in domesticated sunflowers (Helianthus annuus L.)
… affect anthesis and pollination in sunflowers (Helianthus Annuus L.). This study investigates the effect of heat stress on timing of pollen emergence, style elongation rate, pollinator visits, pollen viability and stigma receptivity. We sampled during the anthesis period in a field setting under …
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Extracción de moléculas bioactivas de las hojas de girasol (helianthus annuus) utilizando disolventes a alta presión
… bioactivas a partir de las hojas de girasol (Helianthus annuus L), utilizando dióxido de carbono y adicionando un 50% de los codisolventes agua, etanol-agua y etanol, por tanto, se profundiza en el estudio de extractos de girasol con mayores propiedades alelopáticas que serían útiles para …
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Effects of tillage and mulching on selected soil properties, growth and yield of sunflower (Helianthus annuus L.)
… soil properties, growth and yield of sunflower (Helianthus annuus L.). The experiment was laid out in a split plot design with three replications. The experiment was conducted during the 2018/19 and 2019/20 cropping seasons. Treatments consisted of two (2) tillage methods (conventional and …
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EFFECT OF PINCHING AND SPACING ON THE GROWTH AND DEVELOPMENT OF SUNFLOWERS (HELIANTHUS ANNUUS) IN EAST TEXAS
<p><em>Helianthus annuus</em> cultivars were grown in East Texas to evaluate the effect of pinching and spacing on their growth and development. The first experiment was conducted twice (Trial 1A, 28 April 2017 and Trial 1B, 3 August 2017) to evaluate the effect of pinching at nodes 1, 2, 3, and 4 …
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ΕΠΙΔΡΑΣΗ ΤΟΥ ΑΝΤΑΓΩΝΙΣΜΟΥ ΚΑΙ ΤΗΣ ΞΕΝΗΣ ΓΥΡΗΣ ΣΤΗΝ ΠΡΟΟΔΟ ΓΙΑ ΑΠΟΔΟΣΗ ΣΤΟ ΒΙΟΜΗΧΑΝΙΚΟ ΗΛΙΑΝΘΟ (HELIANTHUS ANNUS L.)
AN OPEN POLLINATED VARIETY OF SUNFLOWER, WAS SELECTED UNDER CONDITIONS OF LACK OF COMPETITION WHICH FAVOURED SELF- FERTILISATION AND UNDER CONDITIONS WHICH FAVOURED CROSS- FERTILISATION. AFTER THE FIRST CYCLE OF SELECTION WITHOUT COMPETITION AND CONDITIONS WHICH FAVOURED SELF-FERTILISATION THE …
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An investigation of the pathway of nitrogen incorporation into the leaf and root metabolism of Helianthus annuus L
… grown and vermiculite- . -3 -3 grown Helianthus annuus fed at 50 µg N cm and 300 ~g N cm feeding level was analysed for nitrate, ammonia, and amino compounds. Nitrate accounted for 771to 94% of the total nitrogen transported via the xylem stream. The pathway of nitrate-N assimilation …
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Effect of small grain residue and tillage method on the emergence and growth of sunflower (Helianthus annuus L.)
Field studies were conducted to determine the effects of wheat and barley residue and tillage method on the emergence and growth of oilseed sunflower. Additional studies were executed to test the effects of wheat, barley, and rye root and straw residue and the effects of cold water extracts of …
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Evolutionary responses to global change: an experimental test of the effect of altered precipitation on hybridization rates in sunflower (Helianthus)
… rates of hybridization between two congeners, Helianthus annuus (common sunflower) and H. petiolaris (prairie sunflower). We found that H. annuus maternal plants produced hybrid progeny more than H. petiolaris maternal plants, with a trend for decreased rates of hybridization with increased …
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