Teff has been a staple food for more than 65 percent of the Ethiopian population. It grows with various agro-ecological areas from above 2 thousand and five hundred meter altitude to the lowest arid places.
However, its productivity rate differs from place to place and the most conducive area for the crop is from 1500 to 2300 meter above sea level said Zerihun Tsegay a researcher in the Ethiopian Biodiversity Institute and a PHD student at AAU.
As to Zerihun, Teff is dominantly produced in a traditional way of farming and its diversity varies from one agro-ecology to the other, the landscape and the soil type. Farmers have their own mechanism to keep the variety of crop specious.
Based on their experience and knowledge after the harvest farmers put the gathered productin open place because the microbes enhance the nutritious content of the crop. Localscientific researchers draw lesson from such practice.
Side by side with the traditional farming activities, farmers utilize inorganic fertilizer but it is proved that, only 25 percent of the mineral elements is absorbed by the plant from the soil and the rest 75 percent mix with other mineral elements and inhibits plants not to get more fertilizer.
In the rainy season, the inorganic fertilizer will be washed away from the soil by flood. It pollutes clean rivers water. On the other hand, when it is blown away by wind, it pollutes the air.
The polluted water put human health at risks and poses cancerous disease by creating hormone anomalies. It has also a negative impact on soil fertility.
Currently, the nation annually imports a 9 Billion Birr worth fertilizer and it also incurs additional transportation cost. Hence, it is high time to the decision makers to work on cost-benefit analysis of the importation of inorganic fertilizer and looking utilizing the organic fertilizer as an alternate mechanism.
Nevertheless, the utilization of inorganic fertilizer is growing from time to time and experts stress that enhancing crop productivity is attributed to the input.
Reflecting his view in this regard, Zerihun said that, there are three types of soils namely acidic, alkaline and neutral and the utilization of the imported fertilizer changes neutral soil in to acidic and alkaline.
Had the cultivation been in the neutral soil productivity with organic fertilizer would have been realized.
As to him, it is obvious that, the utilization of artificial fertilizer rise mineral content and enhance crop productivity but it has its own side effect.
When the types of soil are changed the value of fertilizer will also be changed. The production of fertilizer did not consider the types of the soils.
According to scientists, to raise productivity the normal soil PH must be from 6.7 to 7 percent. But the utilization of fertilizer does not go in line with this proportion as the result, it makes utilizing fertilizer meaningless.
Asked whether there is a possibility to use fertilizer based on the soil type Tsegaye said “I doubt that, in our country experts and extension workers advise farmers only to use the fertilizer irrespective of the soil type. They never consider the soil mineral content or its deficit.
In the north, south, east and western part of the country,fertilizers utilized are Dap and Urea without taking into account the soil types. But soil type differs from one place to another.
But identifying the soil types whether it is acidic, alkaline and neutral and examining its mineral deficit is the job of agricultural experts.
According to experts, because of the repeated utilization of inorganic fertilizer, most of the soil in the Oromiya region has been an alkaline type. For example, phosphate which is found both in fertilizer and in the soil is the major catalyst for the increment of alkalinesubstances.
It also changes the neutral type in to alkaline and acidic type. Particularly the red soil will be changed in to acidic.
As to Zerihun, micro-organisms play crucial role in raising productivity through supplying nutritious elements to both the soil and the plants. They also enable plants to absorb minerals from soil properly or sometimes create anomalies in absorbing systems. Plant and micro-organisms are also mutually benefiting each other.
Microbes decompose minerals and utilize them for themselves. And at other times supply to the plants. When they fix nitrogen, plants provide carbohydrate to microbes. If they do not get it, they don’t supply phosphate to plants.
Plants naturally get carbon dioxide through photosynthesis and supply it to microbes which in turn can fix nitrogen to supply to plants.
In addition, they provide iron, potassium and calcium to plants. These all indicates how they need each other.
Zerihun further said that, by reducing chemical fertilizer enhancing organic fertilizer is possible. Currently, farmers use by products of their crops for cattle forage but instead of using it that way, it is better to let the byproduct in their farm sothat,it fertilizes soil content.
But if it is impossible, it is better to use crop shifting mechanism. That means, using the farm by sawing various seeds such as Teff and cheek-pea interchangeably and in such a way keeping soil fertility can be possible.
It should be noticed that, the excessive use of chemical fertilizer decreases Teff productivity.
Soil productivity also varies from place to place and depending on the type of the soil which comprises physical, chemical and biological components.
The amount and content of fertilizer utilized by farmers also has its own impact in raising soil fertility.
The agro-ecological situation particularly in our context such as Dega and Woinadega either rise productivity or reduce it.
In the Woinadega part of Bishoftu farmers per hectare produce from 14 to 16 quintal Teff.
Whereas in the research centers the production per hectare rises from 18 to 22 quintal. In the Dukem area, farmers produce from 24 to 34 quintal per hectare.