The correct option is (c) 2 and 3 only.
Explanation
Crop rotation is the agricultural practice of growing a series of different types of crops in the same area across sequenced seasons. This method is designed to optimize soil nutrients, improve soil health, and combat pest and weed pressure, standing in contrast to monoculture.Statement 1 is Incorrect: Crop rotation involves growing different crops sequentially, not the same crop. Growing the same crop continuously in the same field is known as monoculture, which typically leads to the depletion of specific soil nutrients and an increase in pest infestations.
Statement 2 is Correct: Leguminous plants (such as pulses, beans, peas, and clover) are essential to this process because they harbor nitrogen-fixing bacteria (Rhizobium) in their root nodules. These bacteria convert atmospheric nitrogen into a usable form, thereby replenishing the soil with nitrogen for the subsequent crops.
Statement 3 is Correct: Legumes are often grown as fodder crops (e.g., berseem or alfalfa) or as green manure during one season of the rotation. Even when grown as fodder for livestock, the root systems remain in the soil to fix nitrogen, supporting the replenishment process.
Key Takeaway: Crop rotation maintains soil fertility and breaks pest cycles by alternating crop families, specifically utilizing legumes to naturally replenish soil nitrogen through biological nitrogen fixation.