Optimum soil-applied nitrogen levels for cotton on a high pH alluvial soil

• Published in: Journal of plant nutrition 1998-01, Vol.21 (6), p.1139-1144
• Main Author: Moore, S.H
• Format: Article
• Language: English
• Subjects: ABONOS; Agronomy. Soil science and plant productions; ALKALINE SOILS; ALLUVIAL SOILS; APPLICATION DATE; APPLICATION RATES; AZOTE; Biological and medical sciences; CROP YIELD; DATE D'APPLICATION; DATE DE PLANTATION; DISPONIBILIDAD DE NUTRIENTES; DISPONIBILITE D'ELEMENT NUTRITIF; DOSE D'APPLICATION; DOSIS DE APLICACION; ENGRAIS; EXIGENCE DES PLANTES; FECHA DE APLICACION; FECHA DE PLANTACION; FERTILIZERS; Fundamental and applied biological sciences. Psychology; General agronomy. Plant production; GOSSYPIUM HIRSUTUM; LOAM SOILS; LOUISIANA; LOUISIANE; LUISIANA; NECESIDADES DE LAS PLANTAS; NITROGEN; Nitrogen fertilization; Nitrogen, phosphorus, potassium fertilizations; NITROGENO; NUTRIENT AVAILABILITY; PH DEL SUELO; PH DU SOL; PLANT REQUIREMENTS; PLANTING DATE; RENDEMENT; RENDEMENT DES CULTURES; RENDIMIENTO; RENDIMIENTO DE CULTIVOS; SILTY SOILS; SOIL PH; Soil-plant relationships. Soil fertility. Fertilization. Amendments; SOL ALCALIN; SOL ALLUVIAL; SOL LIMONEUX; SOL SABLOLIMONEUX; SUELO ALCALINO; SUELO ALUVIAL; SUELO FRANCO; SUELO LIMOSO; YIELD RESPONSE FUNCTIONS; YIELDS
• ISSN: 0190-4167; 1532-4087
• DOI: 10.1080/01904169809365472

Nitrogen (N) is often applied to cotton (Gossypium spp.) in lower Mississippi Delta soils at rates ranging from 47 to 90 kg ha-1. This study was conducted to determine optimum N rates for cotton production on a high pH alluvial soil in the Red River valley of central Louisiana, where higher rates are often recommended to growers. Cotton was planted on a Norwood silt loam soil [fine-silty, mixed (calcareous), thermic Typic Udifluvent] over a 4-year period and received seven rates of N ranging from 0 to 168 kg ha-1 in 28-kg increments. When N was applied at planting, yield response fit a quadratic curve where optimum rates could be estimated. The optimum rates of N was 123 kg N ha-1 in 1990 and 140 kg N ha-1 in 1992. When planting was delayed after N application due to weather or other causes, yield fit to a linear model and increased across the range of treatments. These results indicate that higher amounts of N are needed on the high pH Red River alluvial soils of Louisiana, versus the normal pH Mississippi alluvial soils. Recommended rates should be in the 112 to 134 kg ha-1 range, unless carryover nitrogen may be expected from a previous crop. These results also strongly suggest that N should not be applied far in advance of planting