Less than what? More details are needed.

Dear K Damodara Chari

Please have a look at this useful PDF attachment.

Good luck!

Hai,

Legumes differ in their ability on fixation of nitrogen and it is due to several reasons. Common beans are less in N fixation than most of the legumes. Number of root nodules are less in common beans when compared to other legumes. Beans will generally have less than 100 nodules per plant, soybeans will have several hundreds per plant, and peanuts / ground nut may have 1,000 or more nodules on a well-developed plant. In the case of perennials, these root nodules are long lived and hence fix the N thorough out the growing season. Another reason is delay in nodule formation system and characteristics of the nodule such as weight , size etc apart from the number.

Please also have a look at these useful links and PDF attachment.

http://www.scielo.mec.pt/pdf/rca/v39n4/v39n4a06.pdf

http://www.microbiologyresearch.org/docserver/fulltext/ijsem/63/11/4167_ijs052928.pdf?expires=1533191266&id=id&accname=guest&checksum=32069B5208DF1387BE315A3088D9F7DB

I agree with Jacob Simons. Provide detailed analysis

I agree with Arvind Singh

Because it is difficult to find specific rhizobia to nitrogen fixation and into the soil has a native community that compete with the select rhizobia inoculum, however nowadays you can find inoculum to common beans for several cultivars.

I agree with both Surendran and Alberton. it is supposed be be referred to rood modulation.

It has less leg haemoglobin in its root nodules.

I hope this link will help you

Article Yield and biological nitrogen fixation of common bean (Phase...

regards

It is depending on symbiotically N2-fixing microrganisms and relationship between plants and applyed or natural microrganisms.