Effect of integrated fertilizer application on soil properties and tef (Eragrostis tef [Zucc] Trotter) yield on Vertisols of Northwestern Ethiopia

Abstract

Low soil fertility has become a serious constraint affecting agricultural productivity and food security in North-western Ethiopia. A field experiment was conducted to examine the effects of integrated use of compost and mineral fertilizer on soil properties and tef (Eragrostis tef [Zucc.] Trotter) yields for two years during 2018 and 2019 cropping seasons. The field experiment was arranged in a factorial combination of three rates of Urea/NPSB (0/0, 62.5/75 and 125/150 kg ha⁻¹) and three rates of compost (0, 5 and 10 t ha⁻¹) laid out in randomized complete block design (RCBD) with three replications. Results showed that combined use of compost and mineral fertilizer significantly (p < 0.05) increased soil pH, soil organic carbon (SOC), total nitrogen (TN), available phosphorus (AP), available sulfur (AS) and exchangeable bases but significantly (p < 0.05) decreased soil bulk density (SBD) compared to sole mineral fertilizer application and the control. Furthermore, application of 10 t ha⁻¹ compost combined with 125/150 kg ha⁻¹ Urea/NPSB gave the highest tef dry biomass (8.81 t ha⁻¹) and grain yield (2.40 t ha⁻¹). The economic analysis results also revealed that the highest net benefit (45,761 Birr ha⁻¹) was achieved from the same treatment which was considerably greater than the highest rate of sole mineral fertilizer (37,228.5 Birr ha⁻¹), the highest rate of sole compost (6656 Birr ha⁻¹) and the control (5391 Birr ha⁻¹). We concluded that integrated fertilizer application enhances soil fertility, crop yields and generates better income over individual addition of fertilizers.

Keywords:

• compost
• crop yield
• mineral fertilizer
• net benefit
• soil fertility

Acknowledgments

The authors would like to thank the Dutch project; Capacity building for scaling up of evidence based best practices in Ethiopia (CASCAPE) for funding the research work. We are also grateful to farmers for allowing us to carry out the trial on their farm plot and for their invaluable support during the study periods.

Disclosure statement

No conflict of interest was reported by the authors.