Determination of Soil Phosphorus Critical Level for Corn plant in East Azerbaijan Province

آب و خاک

Article 9, Volume 28, Issue 2, May 2014, Pages 330-342   

Document Type: Research Article

DOI: 10.22067/jsw.v0i0.22181

Author

Adel Reyhanitabar^*

Abstract

Knowledge about the P critical level and plant response to application of P can effectively help with the proper use of this element. In this study, P critical level for corn (Zea mays L.) was determined in 25 combined soils samples from corn fields of East Azerbaijan province during 2011-2012. Corn have been cultivated in two level of P (zero and 40 mg P kg-1) as a factorial experiment in a randomized complete blokes design with three replications .After 60 days, the plant growth parameters in shoot and root were measured. According to the results, in studied soils, clay content ranged from 12.4 to 57.3 with a mean 31.1 %. Calcium carbonate equivalent ranged from 7 to 35 with a mean 21.5 % and active calcium carbonate ranged from 1.47 to 10.78 with a mean 5.1 %. Application of P significantly increased shoot and root dry weight and their P content. According to the results, applied phosphorus levels, soil type and their interaction had a significant effect on corn growth parameters. Critical level of soil P for corn with Olsen-P, based on 90% relative yield, was determined 12, 14.44 and 10.46 (mg P kg-1 soil) by using graphical Cate–Nelson, Cate–Nelson analysis of variance and Mitscherlich-Bray methods, respectively. Mitscherlich-Bray equation coefficient C1 and C2, for Olsen-P, were 0.0956 and 0.0073 (kg soil mg-1P) respectively. Dry weight of shoot was positively and significant correlated with Olsen –P.

Keywords

Phosphorus; corn; Critical level; Cate–Nelson; Mitscherlich-Bray