Genetic variation in Centrosema-Rhizobium symbiosis

Abstract

A greenhouse study carried out with 11 Centrosema sp. genotypes and three Rhizobium sp. strains, for the purpose of obtaining more efficient genetic combinations in the fixation of N₂. Five of the progenies studied carne from two F₂ plants, and three were F₂ plants of interspecific hybridization C. pubescens x C. virginianum. IPEACS line 5.1/64, one Australian cultivar and the common material of C. pubescens were also included. Statistical differences were obtained, between genotypes and between strains in nodule number, the dry weight of nodules and the dry weight of plants, per cent N and total N per plant. The study permitted an analysis of the segregation of genetic combinations, between host and strain with highest N₂ fixation.