Corn Yield and Nitrogen Uptake in Monoculture and in Rotation with Soybean

Abstract

Increasing crop N use efficiency and minimizing environmental risk require an accurate assessment of N taken up by the crop from different sources. We conducted this study to: (i) compare the grain yields of corn (Zea mays L.) in monoculture and in rotation with soybean [Glycine max (L.) Merr.]; (ii) determine the contributions of N from fertilizer, soil, and legume residue to corn in the rotation; and (iii) compare N fertilizer recovery in monoculture and in rotation. Two existing (>10 yr) irrigated corn‐soybean rotation areas in Kansas were used. The soils were Crete silt loam (fine, smectitic, mesic Pachic Argiustolls) and Eudora loam (coarse‐silty, mixed, superactive, mesic Fluventic Hapludolls). To trace the N through the rotation, 15N microplots (2.4 m2) were established int he corn. Microplots also were established in soybean to separately follow 15N from roots + soil and shoots to corn. Crop rotation and fertilizer addition increased corn yield at both sites for two growing seasons. Averaged for 2 yr, the amount of N needed in the continuous corn to achieve yield equal to that in rotation with no N added was equivalent to 144 kg N ha‐1 in the Crete silt loam and 155 kg N ha‐1 in the Eudora loam. Response to N was greater on the Eudora loam, probably because of textural and organic matter differences. In the Eudora soil, significantly higher amounts of soil N were taken up at harvest by corn in rotation, whereas, in the Crete soil, corn in monoculture took up significantly higher amounts of soil N. Corn plants recovered 3 kg N ha‐1 (3%) from soybean residue in the Eudora soil and 5 kg N ha‐1 (14%) in the Crete soil. The main value of legume residue appears to be long‐term maintenance of soil N to ensure adequate delivery to future crops.

Adubação nitrogenada na cultura do milho

“…Após a colheita, o solo das subparcelas foi amostrado, em 20 subamostras por amostra, nas profundidades de 0-0,2 e 0,2-0,4 m, para caracterização química. A recuperação do fertilizante nitrogenado foi calculada subtraindo o N removido na parcela-testemunha do N removido nas outras parcelas, dividido pela quantidade de N aplicado em cada uma delas e multiplicado por 100, conforme citado por Omay et al (1998).…”

“…Estes resultados contrastam com a expectativa dos efeitos benéficos da rotação sobre a monocultura na produtividade de grãos de milho (Peterson & Varvel, 1989;Omay et al, 1998). Uma das prováveis causas da pequena variação na produtividade de grãos entre os sistemas é o teor elevado de matéria orgânica (MO) do solo, no início do experimento (Tabela 4), que sofreu redução com o tempo, e com a profundidade.…”

“…O cultivo de milho em rotação com a soja produz até 30% mais do que se cultivado em monocultura, por causa do aporte de N da leguminosa para a cultura subseqüente (Peterson & Varvel, 1989;Crookston et al, 1991;Bundy et al, 1993;Omay et al, 1998). Resultados semelhantes, principalmente em anos secos ou em condições de estresse, foram obtidos por Raimbault & Vyn (1991) e Randall & Iragavarapu (1995).…”

Quantification of seasonal soil nitrogen mineralization for corn production in eastern Canada

“…Even though soil N supply comprises the main portion of crop N (54-83% of total crop N; Ma et al 1999;Stevens et al 2005), and it may sustain near entire corn growing season (Omay et al 1998), it is still difficult to estimate the quantity and intensity of soil N supply, for the purpose of adequate and timely application of fertilizer N. The concept of potentially mineralizable N (N 0 ) and N mineralization rate constant (k) in a first-order dynamic process has been used to estimate the quantity and intensity of soil N supply (Stanford and Smith 1972;Stanford and Epstein 1974;Zak et al 1999;Campbell et al 1981;Olness 1983;Griffin and Laine 1983). The parameters have clear mechanistic means and can differentiate N supplies among soils which are of genesis difference and distribute from sub-tropic to cool and humid regions (Stanford and Smith 1972;Campbell et al 1981Campbell et al , 1984, among soils with different fertilization and rotation systems (Sanchez et al 2001;Mikha et al 2006), and cultivation histories (Campbell et al 1984).…”

Maize Biomass Production, N-Use Efficiency and Potential Bioethanol Yield, Under Different Cover Cropping Managements, Nitrogen Influxes and Soil Types, in Mediterranean Climate

“…7; following leguminous crops can show improved root growth and root vigour, which can have consequences for the uptake of nutrients and water (Van Zeeland, Lamers, & Van Dijk, 1999). So cover cropping could be a potentially useful practice for obtaining comparable or even higher maize yields with less fertilizer N. This is reflected by different yield responses of maize in monoculture and maize grown in rotation to N fertilization (Lory, Russelle, & Randall, 1995;Omay, Rice, Maddux, & Gordon, 1998;Peterson & Varvel, 1989;Varvel & Peterson, 1990). The decreasing positive effect of cover cropping with increasing N fertilizer level indicated that raising the N fertilizer rate could easily offset the negative effects of maize in monoculture.…”