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United States Department of Agriculture (USDA) 2001


Weed Irrigation Dryland

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


Identification : MONB00657

Pays : Etats Unis

Durée : Oct 1, 2001 à Oct 1, 2006

Mots clés : weed control asclepias avena fatua fungi irrigation seeds mortality dryland farming herbicides cropping systems herbicide evaluation quantitative analysis plant competition plant ecology sugar beets barley crop yields crop quality seed production vegetative propagation crop rotation soil moisture penicillium seed diseases


1. Evaluate registered and experimental herbicides for use in integrated weed management strategies for irrigated and dryland cropping systems of south-central Montana. 2. Quantify the effects of showy milkweed competition on irrigated malt barley and sugar beet yield and quality. Determine if seed production and/or vegetative reproduction significantly contribute to the survival and proliferation of showy milkweed populations in irrigated barley and sugar beet fields. Identify possible management strategies for showy milkweed in sugar beet - barley rotations. 3. Determine the effects of soil moisture potential on wild oat seed mortality and fungi associated with wild oat seeds collected from the soil seedbank. Determine if exposure to Penicillium spp. can cause mortality in wild oat seeds.

Objective 1. Field experiments will be conducted on-station at the Southern Agricultural Research Center and at off-station locations with farmer-cooperators. Experiments will be conducted to evaluate registered and experimental herbicides and factors that affect herbicide performance in sugar beet, barley, wheat, corn, dry beans, and alfalfa. Weed control will be evaluated visually and by sampling weed biomass. Crop tolerance will be evaluated visually and by collecting crop yield data. Objective 2. Experiments will be conducted in irrigated barley and sugar beet fields with a history of milkweed infestation. At each site, plots will be established in areas of the field so that a range of low to high milkweed density areas are represented. Soil samples will be collected in the spring to determine the milkweed seedbank density. A sample of milkweed shoots will be exhumed to determine the proportion of shoots that originated from seed versus root buds. For shoots that originated from root buds, the depth of the root bud will be determined. Samples of milkweed seed from each field will be collected to determine seed viability. At crop maturity, weed and crop biomass and yield parameters will be collected. Objective 3. Field experiments will be conducted to determine the effects of soil moisture potential on weed seed mortality and fungi associated with weed seeds. Wild oat will be used as a model weed species. The experiments will be conducted at the Montana State University Southern Agricultural Research Center. The experiment consists of four supplemental irrigation treatments (0, 2.5, 5.0, and 10 cm of water applied per 4 week period) in a randomized complete block design with three replicates. The experiment will be conducted and evaluated over a two year period. Wild oat seedbanks will be established in the center of each plot in the fall. Plot area surrounding the seedbank will be tilled in the spring and fall and wheat will be planted in rows spaced 30 cm apart at a seeding rate of 27 kg/ha. Seedbank areas of plots will be sampled by removing 3.8-cm dia by 15-cm deep soil cores to estimate the viable seedbank population and to isolate fungi from wild oat seeds. Soil will be sampled each fall and spring, beginning in the fall of the seedbank establishment year. Seeds retrieved from a portion of the soil samples will be tested for viability. Seeds retrieved from the remaining soil samples will be plated on growth media to identify fungi associated with wild oat seeds. Lab experiments will be conducted using a model fungus species to demonstrate the potential ability of microorganisms to cause mortality of weed seeds. The experimental design is a randomized complete block with six replicates and each experiment will be repeated. Treatments consists of two species of seeds (wild oat and wheat) applied with or without an imazalil seed protectant, placed in two soils (silt loam and clay loam), and inoculated with or without Penicillium. Fifty seeds will be added to soil in petri dishes. The seeds will be incubated at 17 C for 8 weeks. Seeds will then be tested for viability or incubated to determine percent of seeds colonized by Penicillium.

Présentation : USDA

Page publiée le 5 décembre 2015, mise à jour le 29 octobre 2017