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Accueil du site → Projets de développement → Projets de recherche pour le Développement → 2001 → INTEGRATED MANAGEMENT OF WINTER ANNUAL GRASS WEEDS IN EASTERN WASHINGTON DRYLAND CROP SYSTEMS

United States Department of Agriculture (USDA) 2001

INTEGRATED MANAGEMENT OF WINTER ANNUAL GRASS WEEDS IN EASTERN WASHINGTON DRYLAND CROP SYSTEMS

Winter Grass Weeds Dryland

United States Department of Agriculture (USDA) Research, Education & Economics Information System (REEIS)

Titre : INTEGRATED MANAGEMENT OF WINTER ANNUAL GRASS WEEDS IN EASTERN WASHINGTON DRYLAND CROP SYSTEMS

Identification : WNP00376

Pays : Etats Unis

Durée : Mar 1, 2001 à Feb 29, 2004

Mots clés : conservation tillage plant competition herbicide resistance herbicide resistant plants plant improvement herbicides aegilops cylindrica seed size seeding rate winter wheat weed control integrated control (weeds) environmental impact cropping systems crop production plant growth seed production plant development resistance management crop rotation dry farming

Partenaire : WASHINGTON STATE UNIVERSITY 240 FRENCH ADMINISTRATION BLDG PULLMAN,WA 99164-0001

Objectifs
1) Determine competitive characteristics of wheat which are most important to minimizing jointed goatgrass growth, seed production, and impact on winter wheat growth and development and seed production. 2) Investigate the biology and ecology of jointed goatgrass. Specifically, determine potential for jointed goatgrass, primarily a winter annual grass species, to emerge and produce seed within a spring-seeded crop. 3) Determine optimal placement and frequency of a herbicide-resistant crop in a rotation to minimize development of resistant weed populations. 4) Investigate new herbicides to improve weed management and environmental suitability for eastern Washington dryland crops. Particular emphasis will be placed on weed management in intensive dryland crop rotations using direct seeding

Descriptif
Obj 1 : Determine competitive characteristics of wheat which are most important to minimizing jointed goatgrass growth, seed production, and impact on winter wheat growth and development and seed production. Seed of two isolines of the variety Nugaines, with mature heights of approximately 1 and 1.5 m, will be separated into three lots : standard, larger, and small. Seed lots for each isoline will be planted with or without jointed goatgrass competition at 100 and 150 kg seed/ha. Weed and crop stand densities will be measured. Wheat grain yields and dockage due to jointed goatgrass will be determined. Experimental design will be a split plot with weed level the main plot. Subplots will be a factorial of 2 isolines x 3 wheat seed sizes x 2 seeding rates. Obj 2 : Investigate the biology and ecology of jointed goatgrass. Determine potential for jointed goatgrass to emerge and produce seed within a spring-seeded crop. Experiments will be established at 3 PNW locations. Treatments will be a factorial arrangement of 3 seeding combinations of jointed goatgrass and spring wheat and four planting dates. The 3 seeding combinations will pure wheat or jointed goatgrass and a mixture of jointed goatgrass and spring wheat. Experimental design will be a factorial of 3 seeding combinations and 4 seeding dates. Jointed goatgrass spikelets will be broadcast on the surface at each planting date. Emergence counts will be taken as crop and weeds develop. Jointed goatgrass heads will be harvested to determine spikelet production. Wheat will be harvested in the pure spring wheat and mixed treatments and yields and dockage due to jointed goatgrass contamination determined. Obj 3 : Determine optimal placement and frequency of a herbicide-resistant crop in a rotation to minimize development of resistant weed populations. Rotation experiments will be established in the high and low rainfall zones of eastern Washington in three and two year rotations, respectively. Initial main treatments will be imidazolinone-resistant wheat or a standard local variety of wheat. Resistant wheat will be sprayed with 34 g/ha imazamox. Standard varieties will not receive a herbicide application for jointed goatgrass control. Following initial year, whole plots will be divided into subplots with subplot treatments being frequency of midazolinone- resistant wheat in the rotation. Surface and soil samples will determine the size and distribution of the jointed goatgrass seed bank. Spikelets harvested from the soil and wheat samples will be mixed with soil in greenhouse flats and germinated. Imazamox resistant jointed goatgrass will be determined by spraying flats with 34 g/ha imazamox and survivors counted. Analysis of jointed goatgrass resistance will be evaluated over three rotation cycles to determine the degree to which an imazamox-resistant jointed goatgrass population is developing. Objective 4 : Investigate new herbicides to improve weed management and environmental suitability for eastern Washington dryland crops. Field tests will be conducted in eastern Washington wheat producing counties to evaluate existing and experimental herbicides for weed control and crop safety.

Présentation : USDA

Page publiée le 1er décembre 2015, mise à jour le 29 octobre 2017