Question

Pulses are rich in protein because of ___________
a) Insectivorous habit
b) High requirement of nitrogen fertilizers
c) Rhizobium
d) Green manuring

Answer 1

Hint: Pulses are rich sources of proteins. They contain twice the amount of protein found in the whole grains. They have the presence of essential vitamins and minerals which are iron, potassium, and folate. Pulses are usually used as the food source of protein content.

Complete answer:
Pulses are the legumes plants that require a high amount of the nitrogen content in them to help them in the production of high protein content. To help them in obtaining the nitrogen the plants have a symbiotic relationship with the rhizobium. Pulses do have the capability to fix atmospheric nitrogen by themselves but they also need the help of the rhizobium species to help them in the fixation of nitrogen from the atmosphere into the soil. The rhizobium penetrates the roots of the plant and multiplies within the root. The plant then responds to it by the formation of the nodules on it. The nodules are the enlarged and swollen portion of the roots where the rhizobium species resides. The rhizobium bacteria then fix the atmospheric nitrogen into the ammonia which is taken by the plants from the roots. The plant provides bacteria with food and energy to fix the atmospheric nitrogen and in exchange, it takes the nitrogen compound fixed by the bacteria.

So, the answer is ‘Rhizobium’.

Note: The pulses can fix the atmospheric nitrogen by themselves. They can fix up to 50-80% of the nitrogen. For further nitrogen requirements, they use the nitrogen present in the soil or from the fertilizer sources.