Browse on keywords: legume nitrogen fixation
Search results on 05/25/13
3809. Ladd, J., J. Butler, and M. Amato. 1986. Nitrogen fixation by legumes and their role as sources of nitrogen for soil and crop.. Biol. Agr. Hort. 3:269-286.
805. Bezdicek, D.. no date. (STEEP green manure plots). unpublished.
Examined 3 legume green manures (red clover, Austrian winter pea, hairy vetch) and harvested spring pea, with 3 incorporations (plow, disk, chemical kill) and 3 N rates (0, 67, 134 kg N/ha). Prior to tillage, red clover and hairy vetch depleted 3.4 cm/m more moisture than spring pea, and AWP depleted 1.8 cm/m more. Soil residual N was highest under spring pea and lowest under red clover. N fixation estimates ranged from 76 for spring pea to 114 for AWP. Winter wheat yield was highest following red clover that had been plowed or disked. Chemical kill appeared to inhibit wheat yield, and N fertilizer could not overcome this depression. Yields after AWP were lower than red clover but higher than spring peas. Recovery of pea and wheat residue N ranged from 7-10% by a following wheat crop. Overseeding of red clover in a spring cereal was successful. T: residual moisture, N; yield response to the various treatments; recovery of N.
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 unpublished.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.
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 unpublished preliminary report, Dept.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.
2507. Heichel, G.H.. 1987. Legumes as a source of nitrogen in conservation tillage systems.. IN: J.F. Power (ed.) The role of legumes in conservation tillage systems..
A review of legume N contributions in crop rotations across the U.S. Covers nitrogen nutrition of legumes, legume nitrogen and companion plants, management effects, nonlegume yield response. T: examples of regional rotations with legumes; seasonal N fixation for various crops in various locations; N transfer from legume to grass; N budgets; N recovery.
2607. Hilander, S. (ed.). 1989. Proceedings of AERO's soil building cropping systems conference. December 7-9, Lewistown, MT. AERO, 44 N. Last Chance Gulch #9, Helena, MT 59601.
Summarizes the talks given at the conference. Much information is from Canadian researchers in Saskatchewan who are working on low water use legumes as fallow replacements.
2673. Holter, V.. 1978. Nitrogen fixation of four legumes in relation to above-ground biomass, root biomass, nodule number, and water content of the soil.. Oikos 31:230-235.
The study attempted to determine which plant characteristic was best correlated to acetylene reduction, and at what drought point it would stop. Four legumes were compared: vetch, red clover, -- clover, and black medic. All showed a drop in acetylene reduction around 8% water content on a clay soil. The correlation of various plant parameters with acetylene reduction was poor.
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
5413. Kisha, T.J.. 1983. Effect of soil salinity and fertilizer nitrogen on growth and N2-fixation in broad bean (Vicia faba L.) and dry bean (Phaseolus vulgaris L.).. M.S. Thesis, Dept. of Plant and Soil Sci., Montana State Univ., Bozeman, MT 59717.