Secondary Metabolites Produced by Xylaria necrophora Are Responsible for Foliar Symptoms Associated with Taproot Decline of Soybean

• DOI: 10.1094/php-03-22-0021-rs
• Publication Date: 2022-05-19T04:47:36Z
• Authors: Teddy Garcia-Aroca; Paul “Trey” Price; José E. Solórzano; David Galo; Sophie B. Sheffield; Vinson P. Doyle
• Keywords: Chlorosis; Taproot; Cutting

Taproot decline (TRD) of soybean ( Glycine max [L] Merr.) is an emerging disease caused by Xylaria necrophora and currently observed in the southern United States. X. infects roots, causing necrosis foliar interveinal chlorosis followed necrosis. The most recent estimates yield losses associated with this (0.57 to 1.18 million bushels) highlight its potential become a major problem for producers region. mechanism which affects foliage remains unknown, but plausible explanation that phytotoxic secondary metabolites (SMs) are produced roots. To test hypothesis, cell-free culture filtrates (CFCFs) from three strains one putative Colletotrichum siamense isolate were used challenge stem cuttings determine if symptoms TRD SMs, tolerance SMs among potentially resistant cultivars identified greenhouse field experiments, specificity across plant species (cotton, peanut, tomato, soybean). Measurements chlorophyll content root length obtained at 7 14 days exposure. Lower shorter roots on all treated CFCFs pathogenic isolates, no effects other observed, suggesting produces detrimental exclusively resistance upon direct exposure does not exist. These results suggest soybean-specific subsequent plants affected TRD.