Phosphorus calibration study under soil test based maize response in bedele district of oromia, west Ethiopia

Abstract

Periodic assessment of soil fertility status and plant nutrients requirement of a given area has vital role in enhancing crop production on sustainable basis. In view of this, on-farm study was carried out in Bedele district of Oromia. The aims of the study were to determine phosphorus critical level and requirement factor for phosphorus recommendation of hybrid maize (BH-660) variety for the district. The treatments of the experiments were four levels of phosphorus (0, 10, 20 and 40kg P/ha), and 92 kg N/ha were laid out in RCBD with two replications. Soil samples were collected from surface soil of the experimental plots (0-20cm depth)before and after planting for laboratory analysis of soil pH (H2O) and available P which is used to. determine phosphorus critical level and requirement factor The results of the study revealed that the soil reaction pH (H2O) were extremely acidic to strongly acidic ranged from 4.43 to 5.42, Very low available P from 1.82 to 4.78 ppm. The study also showed that phosphorus critical level (6ppm) and requirement factor (23.55) were determined for phosphorus recommendation for maize production in the area. The validity of phosphorus critical level was verified by conducting verification trials; accordingly, the economic evaluation showed that STBCRPR would yield 2.23 Ethiopian birr for every birr invested. Thus, farmers in the area might be advised to use soil test based crop response phosphorus recommendation to increase the productivity of maize.