What is one important function of certain bacteria in legume plants?

Nitrogen fixation in root nodules

The correct answer is Option (4): Nitrogen fixation in root nodules

Some bacteria play a crucial role in the process of nitrogen fixation within the root nodules of legume plants. These bacteria, known as rhizobia, have a symbiotic relationship with leguminous plants.

Legume plants have specialized structures called root nodules. Within these nodules, rhizobia bacteria form a mutualistic relationship with the plant. The plant supplies carbohydrates to the bacteria, while the bacteria, in turn, perform nitrogen fixation.

This symbiotic relationship between leguminous plants and rhizobia bacteria is ecologically significant, as it reduces the dependency on synthetic nitrogen fertilizers, which have environmental impacts, and enhances soil fertility by naturally enriching it with nitrogen compounds.