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Search results on 12/17/18
10338. Morrow, L.. 1992. Chloride fertilizers.. Growers Guide, Feb. 1992, p.A6.
Chloride is provided when KCl fertilizers are used. It affects photosynthesis, enzyme activation, cation transport, stomatal activities and other processes. In soil, Cl inhibits the conversion of ammonium to nitrate. This maintains a lower pH near the root. Cl increases the number of non-pathogenic organisms in the rhizosphere. Cl competes with nitrate for plant uptake, and reduces plant nitrate levels, which can also reduce certain plant diseases. Take-all, tanspot, stripe rust, septoria, leaf rust, and common root rot have all bee suppressed by chloride.
1819. Elliott, L.F. (ed.). 1987. STEEP - Conservation concepts and accomplishments.. Washington State Univ. Publ., 662pp..
A compilation of 48 papers covering: tillage and plant maagement; erosion and runoff predictions; plant design; pest management; socio-economic; integrated systems; technology transfer for cropping systems; 22 technical notes. T: many
5735. Rasmussen, P.E. and C.R. Rohde. 1988. Stubble burning effects on winter wheat yield and N utilization under semiarid conditions.. Agronomy J. 80:940-942.
Burning vs. not burning was examined at 3 nitrogen levels over 6 years (3 crops). Burning had no effect on grain yield or grain N uptake. Burning increased straw yield when wheat was fertilized by N, but had no effect on straw N uptake. Burning did not decrease foot rot incidence or severity, but did reduce downy brome density. T: Effects of stubble burning and N fertilization on grain and straw of winter wheat 1980-85. Effect of stubble burning on foot rot infection. Effect of stubble burning on downybrome infestation.
6359. Smiley, R., D. Wilkins, W. Uddin, S. Ott, K. Rhinhart, and S. Case. 1989. Rhizoctonia root rot of wheat and barley.. OR Agr. Expt. Sta. Special Report 840, p. 68-79..
Rhizoctonia root rot is now considered the most severe root disease of barley in the PNW. It is more important than take-all and Pythium on wheat produced in drier areas (<16" precip.). Based on long-term plots at Pendleton, different management systems are unlikely to greatly influence the biological resistance of soils to Rhizoctonia. Rotational crops susceptible to Rhizoctonia include wheat, barley, peas, chickpeas, lentils, and rapeseed. The disease is less apparent on small grains after legumes than after cereals. Rhizoctonia damage is always highest on no-till systems, but yields may not suffer due to improved water relations under conservation tillage. Australian research indicates that applications of N and P fertilizers can reduce the disease. There appear to be detrimental herbicide interactions with Rhizoctonia, particularly Glean on high pH soils. Also, the use of glyphosate increased disease incidence, perhaps by signalling the pathogens to move from the dying plants to newly seeded ones. A delay of at least 2 weeks is suggested between chem kill and planting of a new crop.
6370. Smiley, R.W.. 1990. Seed treatment fungicides for wheat and barley.. Sherman Station Field Day handout, OSU, Moro, OR.
Seed applied fungicides failed to improve yields of winter wheat or were inconsistent from site to site and/or year to year. The most consistent treatment for winter wheat was a combination of Apron and Vitavax 200. This mixture increased wheat yields by 3%. Fall barley yields were either unchanged or reduced, while spring barley showed the best economic response. Thus, an economic response to seed treatment is unlikely in the absence of damaging amounts of smut disease. Since control of smut depends on the combination of fungicide seed treatments and genetic resistance, which has been stable for decades, the use of untreated seed is discouraged to avoid the loss of genetic resistance by cereal cultivars.
10814. Heim, M., R.J. Cook, and D.J. Kirpes. 1986. Economic benefits and costs of biological control of take-all to the Pacific Northwest wheat industry.. Research Bulletin 0988, Agr. Res. Center, Washington State Univ., Pullman, WA.
Take-all can severely lower wheat yields. One possible control is through the use of antagonistic Pseudomonad bacteria applied to wheat seed. Disease surveys in the region verified increased disease problems with grain intensive rotations and with reduced till or no-till farming. Overall, an estimate 600,000 acres are affected by take-all in the region. Estimates of the cost of a commercial bacterial seed treatment were $14.30/ac applied. Wheat yields were assumed to increase an average of 5-10% from this. At a wheat price of $3.00/bu, a minimum 5 bu/ac increase is needed to break even on the treatment.
11017. Cook, R.J.. 1986. Wheat management systems in the Pacific Northwest.. Plant Disease 70(9):894-898.
Strategies for reducing disease problems and increasing yields closer to potentials of the site are described for four agroecosystems: rainfed wheat-fallow, rainfed annual crop; irrigated; western OR and WA.
11057. Cook, R.J.. 1980. Fusarium foot rot of wheat and its control in the Pacific Northwest.. Plant Disease 64:1061-1066.
Fusarium foot rot occurs mainly in low to intermediate rainfall areas of the PNW (20-40 cm) where wheat is grown after fallow. The disease appears related to water stress. Sometimes nitrogen use can induce water stress and was blamed for the disease. Wheat varieties vary in their susceptibility to the disease. The disease can be controlled by minimizing pathogen population increases and by reducing or delaying water stress. Oats should be avoided since they are an excellent host for the disease. Actions to improve water infiltration and storage reduce the chance of water stress. By maintaining residue on the surface, airborne saprophytic fungi will colonize it and prevent Fusarium from doing so. N applications should be based on realistic yields so water stress will not be induced. September seeding, rather than August, avoids excessive foliar growth which can induce water stress.