Fertilizer and soil nitrogen use by corn and border crops in a strip intercropping system

• Published in: Agronomy journal Vol. 90; no. 6; pp. 758 - 762
• Main Authors: Ghaffarzadeh, M, Garcia Prechac, F, Cruse, R.M, Harbur, M.M
• Format: Journal Article
• Language: English
• Published: Madison, WI American Society of Agronomy 01-11-1998
• Subjects: Agronomy. Soil science and plant productions; ammonium nitrate; Avena sativa; Biological and medical sciences; corn stover; crop management; Cropping systems. Cultivation. Soil tillage; Fundamental and applied biological sciences. Psychology; General agronomy. Plant production; Generalities. Cropping systems and patterns; Glycine max; intercropping; Medicago sativa; nitrogen; Nitrogen fertilization; Nitrogen, phosphorus, potassium fertilizations; no-tillage; nutrient uptake; soil fertility; soil water content; Soil-plant relationships. Soil fertility. Fertilization. Amendments; water availability; Zea mays; Iowa; United States; North America; America; Avena sativa; Nitrogen fertilization; Monocotyledones; Cultivated soil; Minimum tillage; Zero tillage; Inorganic element; Cereal crop; Field experiment; Mineral fertilization; Gramineae; Agronomy; Dicotyledones; Angiospermae; Intercropping; Interspecific competition; Nitrogen fertilizer; Labelled compound; Soil tillage; Zea mays; Nutrition; Cropping system; Medicago sativa; N-15; Nitrogen; Glycine max; Oil plant(vegetal); Grain legume; Leguminosae; Spermatophyta; Fodder crop; Soil plant relation
• ISSN: 0002-1962; 1435-0645
• DOI: 10.2134/agronj1998.00021962009000060007x

Corn (Zea mays L.) has greater yield potential when strip-inter-cropped than when monocropped, but this potential may be compromised by a failure to understand how N requirements change with row position and the possible N competition of adjacent crops. A four block, completely randomized, split-plot experiment was conducted on a Haig loam soil (fine, smectitic, mesic Vertic Argiaquolls] in southern Iowa, to determine crop utilization of N fertilizer point-injected into corn rows. Nitrogen fertilizer uptake was evaluated in (i) corn rows injected with labeled N fertilizer; (ii) corn rows adjacent to the injected rows; and (iii) plants at the edge of the adjacent soybean (Glycine max (L.) Merr.] and oat (Avena sativa L.)-alfalfa (Medicago sativa L.) strips. Main treatments consisted of three tillage systems: conventional tillage (CT), reduced tillage (RT), and no-till (NT). Subplot treatments consisted of point injection of 15N-enriched NH4NO3 (67 kg N ha-1) in-row at three row positions within the corn strips. Grain and stover yield, Kjeldahl N, and isotope composition of plant materials were determined. Corn yield and labeled-N recovery differed with tillage to the extent that tillage affected early and total season moisture availability. Labeled-N recovery in labeled rows did not differ with row position. Labeled-N recovery in unlabeled rows or crop borders was typically less than 5% of that recovered by labeled rows. Nitrogen is primarily recovered by the row to which it is applied; therefore, row-by-row precision applications seem to be an appropriate management tool.