Farmers in Jamaica often practise crop rotation, alternating pigeon peas with callaloo. Which of the following best explains why this practice improves soil fertility?

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Question

Farmers in Jamaica often practise crop rotation, alternating pigeon peas with callaloo. Which of the following best explains why this practice improves soil fertility?

Accepted Answer

Pigeon peas have root nodules containing nitrogen-fixing bacteria — Award 1 mark for identifying that legumes like pigeon peas form a mutualistic relationship with Rhizobium bacteria which convert atmospheric N₂ into ammonia, enriching the soil with nitrogen compounds for the next crop. A is incorrect — plants do not release nitrogen gas. C does not explain improved fertility. D is incorrect — denitrifying bacteria remove nitrogen from soil.

Answer

Callaloo roots contain denitrifying bacteria

Answer

Both crops absorb equal amounts of nitrates from the soil

Answer

Callaloo releases nitrogen gas through its leaves

Answer

Pigeon peas have root nodules containing nitrogen-fixing bacteria

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