Browse on keywords: legume WA nitrogen
Search results on 03/22/18
816. Bezdicek, D.. no date. (Influence of residual soil N on N2 fixation; N2 fixation of chickpeas). unpublished.
High levels of residual soil N decreased N2 fixation. There was a negative correlation between the fraction of plant N derived from N2 fixation and total mineralizable N and KCl extractable N. N2 fixation was reduced by about 2.8 kg/ha for each kg/ha of available soil N. Seed yield response from inoculation ranged from 5-70% and was negatively correlated with available soil N. Residual soil moisture in July was greatestfor large seeded legumes > forage legumes > winter wheat. T: N fixation in chickpeas.
826. Bezdicek, D. and R. Lockerman. no date. Crop rotation and the response of cereal crops to nitrogen in the PNW. unpublished.
Experiments conducted at Pullman, WA and Bozeman, MT. Year 1 - legumes (rainfall -Pullman 500 mm, Bozeman 480 mm). Year 2 -Pullman winter wheat + N (rainfall 350 mm); Bozeman barley + N (rainfall 200 mm). Compared fababean, pea, lentil, chickpea, fallow at both locations. Pullman legumes were used as green manure, Bozeman legumes were harvested for seed. N fertilizer equivalents ranged from 30-86 kg/ha N at Pullman (fallow = 125) and from 27-81 kg/ha N at Bozeman (fallow = 53). All cereals responded to added N, although less so at Pullman. More N was removed in seed than was fixed. Seed legumes appeared to fix 50-100 kg/ha N. The rotation effect was more significant at Pullman. T: cereal yields; fertilizer N equivalent; moisture depletion.
846. Bezdicek, D.F., C. Root, and S. Smith. no date. Summary of data on nitrogen fixation in legumes in eastern and central Washington, 1981 and 1982.. unpublished preliminary report, Dept. of Agronomy and Soils.
This report summarizes field data from a number of irrigated and dryland locations in eastern WA. The studies examined nitrogen fixation and nitrogen cycling in the following crops: chickpeas, fababeans, lupins, peas, lentils, soybeans, medics, sweetclover, vetch, and clovers. Inoculation of chickpeas with Rhizobium resulted in 10-50% increases in seed yield. N fixation was estimated at 20-50 lb/ac. Fixation varied greatly depending on the Rhizobium strain. Fababean N fixation ranged from 0-150 lb/ac. With chickpeas, N fixation declined rapidly with increasing levels of soil available-N. In most cases, harvest of the chickpea seed resulted in a net loss of N from the soil. Rhizobium survival and nodulation was inhibited by chickpea seed treatment with Captan, but less so with Ridomil. Response of peasand chickpeas to added molybdenum was observed in several trials.
1015. Bowren, K.E. (ed.).. 1986. Soil improvement with legumes.. Saskatchewan Agriculture, Soils and Crops Branch.
This excellent publication summarizes research over the past 40 years pertaining to the use of legumes for soil improvement in Saskatchewan. The role of legumes in maintaining soil nitrogen was crucial prior to available fertilizer. But their value extends beyond their nitrogen contribution to the improvement of soil physical properties. One study found the tillage draft requirement to be up to one-third lower where legumes had been a regular part of the rotation. The positive effects of alfalfa were measured for over ten years in a series of wheat crops compared to plots with no alfalfa. Over 17 years, the average grain yield from a wheat-wheat/clover-clover green manure rotation with no fertilizer were 30% higher that a wheat-wheat-fallow rotation with fertilizer. Moisture depletion by legumes is the biggest hurdle to their use in very dry areas. Adequate fertility for the legumes is necessary to maximize their benefit. Use of selected Rhizobium strains can improve nitrogen fixation, especially on acid soils. Several varieties of sweetclover are mentioned with adaptation to forage or green manure use. The booklet has numerous color photos and many data tables and figures.
2965. Ingham, I.M.. 1924. Effect of legumes in rotation upon the nitrogen content of the soil.. M.S. Thesis, Washington State College, Pullman, WA.
Soils at WSC farm were sampled to show residual effect of legumes upon following crops of wheat, and upon the N content of soil. T: Effect of legumes upon the following crops as shown by yields of wheat. Changes in the N content of soils after 5 years of crop rotations. Influence of various rotations on the N/C ratio of the soil.
3589. Kirby, E.M.. 1987. Soil moisture depletion and wheat yield response from annual legumes in the Pacific Northwest. M.S. Thesis, Dept. of Agronomy and Soils, WSU, Pullman, WA.
Legumes included chickpea, spring pea, lentil, fababean, sweetclover, rose clover, black medic, barrel medic. Sweetclover depleted more soil moisture than other legumes. Wheat yield increased following legumes relative to that after barley. Highest yield followed legume green manure with additional fertilizer N. Grain yields were similar for fallow, lentil, pea, chickpea, and fababean. T: soil moisture depletion; yield, N content of soil and grain.
3935. Mahler, R.L., D.F. Bezdicek, and R. Witters. 1979. Influence of slope position on nitrogen fixation and yield of dry peas.. Agronomy J. 71:348-351.
Total seasonal N2 fixation estimates: bottomland - 69; south slope - 22; ridgetop - 17 kg N/ha. Pea yields were 2100 kg/ha for the bottomland and 480 kg/ha for the ridgetop, and were related to soil moisture depletion of 22 cm and 9 cm respectively. Greater plant N and DM were obtained in the greenhouse when peas were inoculated with Rhizobium isolates from the north slope when compared to other isolates. T: soil water depletion
4115. Mathers, A.C., B.A. Stewert and B. Blair. 1975. Nitrate-nitrogen removal from soil profiles by alfalfa.. J. Environmental Quality, 4(3):403-405.
Alfalfa was shown to be effective in removing nitrate from soil profiles deeper than the annual crop rooting zone. In spite of being a N-fixer, alfalfa will utilize nitrogen from the soil first. It can be used in rotation with annual crops to reduce groundwater contamination by agricultural applications of N. T: Nitrate-N removal from soil by alfalfa by depth.
5065. Patten, A.G.. 1982. Comparison of nitrogen and phosphorous flows on an organic and conventional farm.. M.S. Thesis, Dept. of Agronomy and Soils, WSU, Pullman, WA.
Two adjacent farms, one organically managed and the other conventionally managed, located in the Palouse region of eastern WA, were studied for 2 years. Soil organic matter, total N, extractable P, and extractable K tended to be higher in the top 30 cm of soil from the organic farm. Mineral nitrogen in the top 30 cm of soil from the conventional farm was higher than or equal to that of the organic farm. Average long-term changes calculated in soil N and P pools resulted in substantial deficits of 44 and 14 kg/ha/yr, respectively, for the organic farm and 23 and 5 kg/ha/yr for the conventional farm. However, nutrients deficits were not reflected in lower soil N and P levels in the plot area tested on the organic farm as compared to the plot area on the conventional farm.
6248. Sievers, F.J. and H.F. Holtz. 1922. The silt loam soils of eastern Washington and their management.. WA Agr. Expt. Sta. Bull. #166.
A broad treatment of agronomy and soil management during 39 years of cropping 22% N and 35% OM has been lost. T: Comparison of nitrogen content of virgin soil and soil cropped 30 years. Organic carbon in virgin soil and soil cropped 30 years. Straw vs. nitrate development in Palouse silt-loam. High N residue as supplement to straw in nitrate development. Effects of manure on N and C in Palouse silt loam, 18 years of results. Effect of legumes on N and C.