Is air-drying of soil samples an appropriate step in determining plant available potassium for corn?. (9th November 2016)

• Record Type: Journal Article
• Authors: Rakkar, Manbir Kaur; Franzen, David; Chatterjee, Amitava
• Is Part Of: Journal of plant nutrition. Volume 39:Number 13(2016)
• Page Start: 1979
• Page End: 1988
• Publication Date: 2016-11-09
• Subjects: Potassium -- air-dried -- corn; Plants -- Nutrition -- Periodicals; Plants -- Effect of minerals on -- Periodicals; Deficiency diseases in plants -- Periodicals; 575.76
• DOI: 10.1080/01904167.2016.1161790
• Languages: English
• ISSNs: 0190-4167

Abstract

ABSTRACT: Potassium (K) fertilizer recommendations are mainly based on air -dried soil samples which can lead to over- or under-estimation of plant available soil K. Three on-farm trials were conducted in North Dakota and Minnesota to determine the variation of soil test-K between air-dried (KDry ) and field moist (KMoist ) soil samples. The differences between KDry and KMoist decreased exponentially as soil K increased, but increased linearly with increasing soil moisture. Soil drying influenced the plant available soil K-test value, producing higher K values compared to the moist soil K. It is unclear based on these initial experiments which method might produce a more predictable K critical value to aid in directing K application for corn in this region.