An In Vitro Assay to Evaluate Sources of Resistance in Asparagus spp. to Fusarium Crown and Root Rot

Publisher Website
Google Scholar
Abstract
Asparagus spp. grown aseptically in test tues containing Hoagland''s solution and agar were inoculated with spore suspensions of a pthogenic isolates of Fusarium oxysporum f. s. asparagi or F. moniliform. Disease severely was assessed after 3 wk, using a scale based on percentage of root tissue infected as evidence by lesions. Species of Asparagus susceptible to F. o. f. sp. asparagi were used to determine the optimal spore concentration for disease developement and to evaluate the virulence of several Michigan isolates of F. o. f. sp. asparagi and F. moniliform. Inoculations with 1 ml of conidial suspension (106 conidia per milliter) of F. o. f. sp. asparagi or F. moniliforme produced consistently high disease ratings on susceptibile seedlings. Disease reactions of resistant and susceptibile species of Asparagus in the vitro assay were compared with those obtained from transplants in greenhouse elevation. Seedlings of S. sprengeri and A. myersii were rated as resistant in the vitro assay, whereas A. pulmonsus and A. setaceous ''pyrimidalis'', A. palestinus, A. stipularis, and all cultivars of C. officinalis were susceptible. This method represents a rapid, relatively inexpensive, technique for evaluating Asparagus spp. germ plasm for resistance to Fusarium crown and root rot.

This publication has 1 reference indexed in Scilit: