Resumen

SANCHEZ-GARCIA, Bertha María et al. Fusarium lateritium: New pathogen of bean roots in Mexico. Agric. Téc. Méx [online]. 2006, vol.32, n.3, pp.251-257. ISSN 0568-2517.

Root rots in common bean are caused by a complex of soil fungal species. In Mexico, 10 Fusarium species have been identifi ed in association with root rots in common bean and it has been suggested that F. lateritium has a role as bean pathogen due to its high frequency and wide distribution in several states of central Mexico. In this investigation, the pathogenicity of seven isolates of F. lateritium, obtained from four different Mexican states, was evaluated on the common bean cultivar Montcalm (Andean gene pool). The time of appearance and characteristics of symptoms caused by F. lateritium were observed on cv. Montcalm and compared to those symptoms caused by F. solani on the same cultivar. All F. lateritium isolates caused symptoms on the roots and hypocotyls of the inoculated plants and signifi cant differences were observed among isolates and between them and the control (p <0.01). The isolates caused reactions from intermediate to susceptible on cv. Montcalm which suggests poor variation in the agressiveness of the isolates of F. lateritium when inoculated on common bean. The fungus recovered was only from the inoculated plants. The symptoms caused by F. lateritium were observed seven days after inoculation and were distinguishable from those caused by F. solani at twenty one days after innoculation. Results indicated that the F. lateritium isolates obtained from common bean roots in central Mexico are pathogenic to this crop and that the cv. Montcalm is susceptible.

Palabras llave : Phaseolus vulgaris L; cv. Montcalm; phatogenicity; symptoms.