Rhizobium Culture (Teeka) for Successful Cultivation of Rabi Legume Fodder-Berseem

摘要

BERSEEM (Trifolium alexandrinum) is the major legume multicut fodder crop grown in the Punjab state. It is rich in nitrogen and protein (20.5%) A diet consisting of only berseem is adequate for milch animals yielding up to 10 litres of milk. The highprotein content of berseem is not due to the nitrogen derived from soil or fertilizer, but the crop is capable of fixing atmospheric nitrogen. An hectare of berseem crop is able to fix around 200-400 kg nitrogen. Due to fixation of nitrogen from the air,the use of fertilizer nitrogen can be omitted for this crop. The nitrogen from the air is taken up by berseem only in the presence of a bacterium called Rhizobium. These bacteria enter the root cortex ceils through root hairs and profusely multiply there, which ultimately take the shape of an outgrowth on the root called nodules. These nodules act as minifactories leading to the production of ammonia from nitrogen present in the air. These bacteria multiply in number in the nodules using the photosynthetic carbohydrates from the plant. After the death of the plant the bacteria are released into the soil and can live there as a saprophyte, using dead organic matter. The specific Rhizobium i.e. Rhizobium trljolii is required to invade the berseem root and cause nodulation.