Nodulation Study in Some Varieties of Frenchbean Crop (Phaseolus vulgaris L.)

ABSTRACT: In the present fuel subsidized agriculture practices, leguminous plants play an unique role by fixing nitrogen through symbiotic association with Rhizobium or Bradyrhizobium. Among the legumes, French bean or Phaseolus vulgaris L. Which are commonly known as Rajmash are used profusely by the common people as an alternative diet of protein. It is very nutritious and contain 22.9 % of protein, 1.2 % of fat, 60.6 % of carbohydrate and a large number of minerals like calcium (260 mg/100g of seed), phosphorus (101 mg/100g of seed) and iron (5.8 mg/100g of seed). The genus Phaseolus belongs to the family leguminaceae, subfamily Papilionaceae with diploid chromosome number 2n = 22. Phaseolus vulgaris has a wide range of acceptability for different species of Rhizobium. It can be nodulated by Rhizobium leguminosarum bv. phaseoli, Rhizobium tropici or rhizobium etli. Five varieties of Phaseolus vulgaris viz Cirpir-50, Local, Anupam, Selection 9 and Kalingpong were studied in respect of their nodular characters and yield in response to (i) mixed culture of Rhizobium strains,(ii) Rhizobium + PSB and (iii) Rhizobium +PSB +KM treatments. Moreover, genetic parameters of variation and correlation coefficient of yield contributing characters with nodular characters were also estimated. The main objective of these estimations is to understand the association of biological nitrogen fixing characters with yield contributing characters. Among these three treatments, a considerable increase in expression of all the characters wa