Soil fertility and plant nutrition research on tef in Ethiopia
2001
Tekalign Mamo | Teklu Erkosa | Balesh Tulema (EARO, Addis Abeba (Ethiopia))
The necessity of fertilizing tef especially with nitrogen (N) has been proven both by nationwide and site-specific fertilizer-rate trials. Phosphorous (P) application is of secondary importance and is recommended at minimum levels of application, except on highly weathered red soils that fix considerable quantity of the applied P. The optiumu rate of n application is 60 Kg ha-1. Applications beyond this rate aggravate lodging, indicating the need for the development of non-lodging varieties. Generally, it has been possible to increase tef grain yield up to 2.5 t ha-1 on research fields and 2 t ha-1 on farmers' fields following improved cultural practices including fertilizer application against the national average of 1 t ha-1. Because the application time of N is largely infuenced by climatic and soil factors, it is difficult to make general recommendations. However, in order to minimize N loss due to leaching or other means, split application where N is applied during the maximum growth period of the crop is recommended; conversely, for lower levels of N, one time application at the appropriate growth stage has been considered a better practice. When tef is grown after legume crop, reducing the rate of N by 50% did not result in any significant yield reduction compared to yield obtained from the recommended dose of N application. The results from other studies that dealt with dry-matter accumulation and nutrient uptake, mycorrhizal and micronutrient relationships in the crop, N-use efficiency of tef varieties, Fe-nutrition and effects of alley cropping are described.
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