The biofertilization of crops with plant-growth-promoting microorganisms is currently considered as a healthy alternative to chemical fertilization. However, only microorganisms safe for humans can be used as biofertilizers, particularly in vegetables that are raw consumed, in order to avoid sanitary problems derived from the presence of pathogenic bacteria in the final products. In the present work we showed that Rhizobium strains colonize the roots of tomato and pepper plants promoting their growth in different production stages increasing yield and quality of seedlings and fruits. Our results confirmed those obtained in cereals and alimentary oil producing plants extending the number of non-legumes susceptible to be biofertilized with rhizobia to those whose fruits are raw consumed. This is a relevant conclusion since safety of rhizobia for human health has been demonstrated after several decades of legume inoculation ensuring that they are optimal bacteria for biofertilization.

A strain, PEPV15 T , was isolated from a nodule on Phaseolus vulgaris grown in soil in northern Spain. Phylogenetic analyses of 16S rRNA and atpD genes showed that this strain belongs to the genus Phyllobacterium. The most closely related species were, in both cases, Phyllobacterium brassicacearum, Phyllobacterium bourgognense and Phyllobacterium trifolii, the type strains of which gave sequence similarities of 98.9, 98.6 and 98.4 %, respectively, in the 16S rRNA gene and 88.1, 87.5 and 88.7 %, respectively, in the atpD gene. PEPV15 T contained Q-10 as the major quinone (88 %) and low amounts of Q-9 (12 %). It differed from its closest relatives in its growth in diverse culture conditions and in the assimilation of several carbon sources. The strain was not able to produce nodules in Phaseolus vulgaris. The results of DNA-DNA hybridization, phenotypic tests and fatty acid analyses confirmed that this strain represents a novel species of the genus Phyllobacterium for which the name Phyllobacterium endophyticum sp. nov. is proposed; the type strain is PEPV15 T (5LMG 26470 T 5CECT 7949 T ). An emended description of the genus Phyllobacterium is also provided.Phaseolus vulgaris is the most important Phaseolus species in the human diet, being commonly cultivated in northern Spain where it is nodulated by Rhizobium leguminosarum (García-Fraile et al., 2010). Rhizobia coexist with other endophytic bacteria in bean nodules, such as Cohnella phaseoli isolated from nodules of Phaseolus coccineus in Spain (García-Fraile et al., 2008). In the present work we report a novel non-nodulating strain from the genus Phyllobacterium, PEPV15 T , isolated from root nodules of Phaseolus vulgaris in Salamanca (Spain). The genus Phyllobacterium was described by Knösel in 1962 and, at the time of writing, contained seven species, Phyllobacterium myrsinacearum isolated from leaf nodules of Myrsinaceae (Mergaert et al., 2002), Phyllobacterium catacumbae isolated from a volcanic rock (Jurado et al., 2005), Phyllobacterium trifolii nodulating Trifolium (Valverde et al., 2005) and four species isolated from the rhizoplane of different plants, Phyllobacterium brassicacearum, Phyllobacterium bourgognense, Phyllobacterium leguminum and Phyllobacterium ifriqiyense (Mantelin et al., 2006). The data obtained in this study show that strain PEPV15 T belongs to a novel species of genus Phyllobacterium.Strain PEPV15 T was isolated from a nodule of Phaseolus vulgaris growing in Pedrosillo el Ralo (41 u 039 530 N 5 u 339 190 W; Salamanca, northern Spain) during a study of rhizobia and nodular endophytes present in different legumes. To sterilize the root nodules, they were washed several times with sterile distilled water and were then surface-sterilized in HgCl 2 (2.5 %, w/v) for 2 min. The nodules were rinsed five times with sterile distilled water and then crushed using a sterile glass rod. The homogenized nodule tissue was inoculated on yeast mannitol agar, YMA (Vincent, 1970) modified (10 g mannitol l 21 , 1 g yeast extract l 21 , 0.2 g K 2 HPO 4 l ...

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