Strategies for the efficiency of common bean selection for resistance to fusarium wilt

Abstract

The objective of this work was to improve the efficiency of common bean lines selection for resistance to Fusarium oxysporum f.sp. phaseoli. Seven methods of inoculation were compared, using four common bean lines in a randomized complete design, in 4x7 factorial, with five replications. Lines reaction was evaluated at 21 days after inoculation. In order to identify the best date for severity evaluation, 18 common bean lines were inoculated through root immersion in a suspension of spores, with roots cut, in completely randomized design, with 15 replications. The disease progress was measured at 7, 14, 21 and 28 days after inoculation. The effect of number of replications from 5 to 15 was simulated, using data from 15 replications, with 20 common bean lines. The best methods to discriminate the lines were root immersions in a suspension of spores – with or without cut of the roots. Disease evaluation should be done at least 21 days after inoculation. Five replications are sufficient to classify the lines of common bean to fusarium wilt.