Bacteria found in root nodules of legumes are

The $hup$ gene is found in .........

Rhizobium lives symbiotically with root nodules and fixes atmospheric nitrogen. It provides nitrogenous compounds to the host and in turn takes food from the host. This food taken by the bacterium is:

Which of the following plants does not have $Rhizobium$-containing root nodules?

In which of the following are root nodules found?

Nitrogen fixation in the root nodules of $Alnus$ is performed by: