Browse on keywords: crop rotation wheat nitrogen
Search results on 06/23/18
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 unpublished.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.
2756. Huggins, D.R., W.L. Pan, and J.L. Smith. 1989. Improving yield, percent protein, and N use efficiency of no-till hard red spring wheat through crop rotation and fall N fertilization.. Proceedings, 40th Far West Fertilizer Conference,.
In a field experiment near Pullman, WA, all fall and split fall-spring N applications significantly increased percent protein and N uptake efficiency as compared to all spring applications, while yields were unaffected. Protein increase was attributed to enhanced late season uptake, due to better positional availability of deep soil N. In another experiment, yield of hard red spring wheat was 10% greater when no-tilled into Austrian winter pea stubble (for seed) as compared to winter wheat stubble, while grain N and percent protein were not affected. The difference in yield was not eliminated by optimized N rates, indicating other rotation effects.
4807. Nelson, A.L.. 1950. Methods of tillage for winter wheat.. WY Agr. Expt. Sta. Bulletin 300.
Fallow/winter wheat production decreased soil N by 33% in the top 6" over 35 years. Continuous cropping lost 24% of the soil N. Crop rotations using green manure every 4th year did not decrease the loss of soil N. Average winter wheat yields (bu/ac) over 34 years for 3 rotations were: oats/rye(GM)/winter wheat/corn - 12.9; oats/peas(GM)/winter wheat/corn - 12.7; fallow/winter wheat - 13.7; oats/corn/winter wheat/rye - 13.2; oats/corn/winter wheat/peas - 14.1; oats/corn/winter wheat/fallow - 13.2. It was observed that green manure took years to break down. Tillage with an eccentric one-way increased winter wheat yields 2 bu/ac over 10 years compared to plowing. The eccentric one-way conserved moisture. Continuous cropping resulted in winter wheat yields 55% of biennial yields following fallow. Soil moisture was 3-4% lower in October after continuous cropping versus fallow.
5954. Rosell, R.A., R. Martinez, K. Sommer and R. Miranda. 1982. Relationship of crop rotation and nitrogen availability for wheat in semiarid Argentina.. Plant Nutrition 2:551.
A sequence of small grains, annual natural pasture with grazing and a short (3 months) summer-fall fallowing showed low productivity when compared with a sequence of continuous grain with a long (6 months) fallowing. Wheat yields, number of ears per surface area and total nitrogen uptake were two times higher with long fallowing. Fertilizers are rarely used. Long-term average yields are in the order of 1.2 tons per hectare.