Aphanomyces cochlioides zoospores

Fig. (3). Response of Aphanomyces cochlioides zoospores toward spinach roots. A. Photomicrograph (dark field) of aggregated zoospores (docs dose to root surface) jusi behind rooi cap of spinach root tip. B. A mass of cystospores (arrow) on spinach rooi (11],...

Fig. (4). Morphological changes (developmental transitions) of Aphanomyces cochlioides zoospores triggered by a host-specific plant signal, cochliophilin A (3). White bars 1 jjM.

Table 3. Activities of Some Nonhost Plant Extracts3 toward Aphanomyces cochlioides Zoospores...

HOST-SPECIFIC ZOOSPORE ATTRACTANTS OF THE FUNGUS APHANOMYCES COCHLIOIDES, THE CAUSE OF SPINACH ROOT ROT... 

Table 7. Results of a Preliminary Screening Test for Zoospore Attractants in Roots of Species Compatible and Incompatible with Aphanomyces cochlioides...

Table 11. Attractant Effect of the Ferulamide Derivatives (69 and 70) on Zoospores of Aphanomyces cochlioides...

Twelve flavones (1, 6,10, 53-55, 57-59, 77-79) including cochliophilin A (6), and a chromone (64), were chemically prepared in order to compare their attractant effects on zoospores of Aphanomyces cochlioides. 

We thank Professors R. Yokosawa, F. Tomita, and M. Fujimura for kindly supplying the fungal strains, Aphanomyces cochlioides, Cladosporium herbarum, and Neurospora crassa, respectively. Much of the research on which this review is based, has been carried out by the following students, Masters Y. Matsukura, N. Toda, and H. Katsuta (benzimidazole antidotes), and by Dr. T. Horio Masters T. Takayama, H. Kikuchi, K. Ohkawa, and M. Mizutani (zoospore attractants). 

Table 1 Responses of zoospores toward the extracts of plants belonging to different families and varying levels of compatibility with Aphanomyces cochlioides ...

Secondary Metabolites with Diverse Activities toward Phytopathogenic Zoospores of Aphanomyces cochlioides in Host and Nonhost Plants... 

Cochliophilin A (6) has previously been isolated from sugar beet roots infected with the basidiomycete fungus Rhizoctonia solani (Thanatephorus cucumeris) [9]. However, it is not yet known if this compound occurs in healthy, uninfected roots of sugar beet, nor if it has any attractant effect on the hyphae of R. solani, a fungus that is only distantly related to the zoospore-producing species of Aphanomyces. As A. cochlioides may cause... 

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