Browse on keywords: moisture nitrogen fixation
Search results on 06/20/13
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 unpublished.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 unpublished.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.