Phosphorus Response and Fertilizer Recommendations under Balanced Fertilizers for Tef (Eragrostis tef) Grown on Vertisol in the Central Highlands of Ethiopia

Abstract

Phosphorous response and fertilizer recommendation under balanced fertilizer study was conducted for tef grown on Vertisols in Dendi district, West Shewa, in central highlands of Ethiopia. The experiment was arranged in a complete block design with six levels of phosphorous fertilizer (0, 10, 20, 30 and 40 kg ha^-1) with three replications. Based on a yield difference between the control and the P treatments, 80% of sites responded to P fertilizer. The application of phosphorous fertilizer at different rates increased grain yield of tef, up to 13.6% as compared to the control (zero p treatment). Extractable soil P concentrations (Olsen method, 0- 20 cm depth) three weeks after planting significantly responded to P fertilizer rate. Correlations of relative yield soil phosphorous values showed that the soil phosphorous levels greater than 15.6 mg kg^-1 (critical phosphorous concentration) was found to be sufficient for tef production. The average phosphorous requirement factor (Pf) calculated from soil phosphorous values of all treatments for the study area was 12.6. In the absence of a soil test, a recommendation of 30 kg P ha^-1 to prevent a potential loss of tef. Further field trials are required to determine interactions between P response and the effects of climate, soil properties, and other management practices.

Keywords: Critical P concentration, Phosphorus, Relative yield, Tef, Vertisol

DOI: 10.7176/JNSR/11-20-01

Publication date:October 31^st 2020