Potassium release characteristics, potassium balance, and fingermillet (Eleusine coracana G.) yield sustainability in a 27-year long experiment on an Alfisol in the semi-arid tropical India

• Published in: Plant and soil Vol. 374; no. 1/2; pp. 315 - 330
• Main Authors: Srinivasarao, Ch, Kundu, Sumanta, Ramachandrappa, B. K., Reddy, Sharanbhoopal, Lal, Rattan, Venkateswarlu, B., Sahrawat, K. L., Naik, R. Prakash
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer 01.01.2014; Springer Netherlands; Springer Nature B.V
• Subjects: Agricultural production; Agricultural research; Agricultural site preparation; Agricultural soils; Agrology; Agronomy. Soil science and plant productions; Animal, plant and microbial ecology; Arid zones; Biological and medical sciences; Biomedical and Life Sciences; Clay soils; Crop yields; Ecology; Eleusine coracana; Farmyard manure; Fundamental and applied biological sciences. Psychology; General agronomy. Plant production; Health aspects; Life Sciences; Millet; Nutrient management; Nutritional aspects; Plant Physiology; Plant Sciences; Plants; Potassium; Potassium in the body; Regular Article; Soil conservation; Soil fertility; Soil science; Soil Science & Conservation; Soil-plant relationships. Soil fertility; Soil-plant relationships. Soil fertility. Fertilization. Amendments; Studies; Sustainable agriculture; Asia; South Asia; India; K release; Semi-arid tropics; Soil reserve K; Rainfed fingermillet; Yield sustainability; K balance; Reserve; Monocotyledones; Tropical zone; System sustainability; Climatic zone; Cereal crop; Gramineae; Semi arid zone; Angiospermae; Experimentation; Release; Arid environment; Alfisols; Balances; Mineral soils; Alkali metal; Eleusine coracana; Characteristics; Spermatophyta; Soil plant relation; Balance; Potassium
• ISSN: 0032-079X; 1573-5036
• DOI: 10.1007/s11104-013-1877-8

Aims In Alfisols, potassium (K) deficiency limits productivity, as these soils are poor in K-bearing minerals such as mica. As nutrient management practices greatly influence K nutrition of crops especially in the longer term, we evaluated the effects of 27 (1978-2004) years of cropping fingermillet (Eleusine coracana G.) under different manure and mineral fertilizer treatments on K release, balance and yield sustainability on K deficient Alfisols in the semi-arid tropical region of southern India. Methods Fingermillet (variety: PR-202) was grown each year under rainfed conditions with 5 different nutrient management treatments: control (no amendment), 10 Mg ha⁻¹ farm yard manure (FYM), 10 Mg ha⁻¹ FYM + 50 % NPK, 10 Mg ha⁻¹ FYM + 100 % NPK and 100 % NPK. Potassium release characteristics in the soil profile were determined using 1 N boiling HNO₃ (strong extracting solution), 0.01 M HCl (medium extracting solution) and 0.01 M CaCl₂ (mild extracting solution). Results Continuous cropping of Alfisols for 27 years resulted in a decrease in K supplying capacity due to soil K depletion through crop K uptake. In soils without K addition, inherent soil supply could not meet the K requirement of fingermillet; thus, a negative K balance following 27 years of cropping affected K nutrition of the crop in all the treatments. As a result, the highest sustainable yield index (SYI) was observed using an integrated nutrient supply (combined application of nutrients from organic and inorganic sources), and the lowest index was obtained without K additions. Conclusion For balanced nutrient management in cereal production systems, K nutrition needs urgent attention in the K deficient Alfisol region of southern India. Addition of any amount of organic manures available at field level offers an alternative strategy for maintaining soil K fertility to improve and sustain crop productivity.