Suppression of Bacterial Blight by a Bacterial Community Isolated from the Guttation Fluids of Anthuriums

Abstract

Growth and survival of Xanthomonas campestris pv. dieffenbachiae in guttation fluids (xylem sap exuded from leaf margins) of anthuriums were suppressed by several bacterial strains indigenous to leaves of various anthurium cultivars. Inhibition of growth was not observed in filter-sterilized guttation fluids and was restored to original levels only by reintroducing specific mixtures of bacteria into filter-sterilized guttation fluids. The inhibitory effect was related to the species in the bacterial community rather than to the total numbers of bacteria in the guttation fluids. One very effective bacterial community consisted of five species isolated from inhibitory guttation fluids of two susceptible anthurium cultivars. The individual strains in this community had no effect on the pathogen, but the mixture was inhibitory to X. campestris pv. dieffenbachiae in guttation fluids. The populations of the individual strains remained near the initial inoculum levels for at least 14 days. The effect of the five inhibitory strains on reducing disease in susceptible anthurium plants was tested by using a bioluminescent strain ofX. campestris pv. dieffenbachiae to monitor the progression of disease in leaves nondestructively. Invasion of the pathogen through hydathodes at leaf margins was reduced by applying the strain mixture to the leaves. When the strain mixture was applied directly to wounds created on the leaf margins, the pathogen failed to invade through the wounds. This bacterial community has potential for biological control of anthurium blight.

Hydathodal leaf teeth of Chloranthus japonicus (Chloranthaceae) prevent guttation‐induced flooding of the mesophyll

“…auxin, cytokinin), flavonoid, nitrogen, potassium, and phosphorous metabolism (Largarde et al 1996;Aloni et al 2003;Burkle et al 2003;Pilot et al 2004;Wang et al 2004). Furthermore, numerous substances such as carbohydrates, amino acids, ions (calcium, potassium, boron), and proteins (peroxidases) have been identified in guttation sap (Curtis & Lersten 1974;Belin-Depoux 1989;Magwa, Lindner, & Brand 1993;Fukui, Fukui, & Alvarez 1999;Kerstetter, Zepp, & Carreira 1998;Grunwald et al 2003). Epithem is likely to be the source for many of these substances, owing to a high density of metabolic organelles.…”

BIOLOGICAL CONTROL OF POSTHARVEST DISEASES OF FRUITS

“…The application of antagonist mixtures has reduced variability and improved efficacy of biocontrol in many systems, some of which include pathogens that infect fruit (67,71,120,135,144,151). With the exception of work on biocontrol of anthurium blight, where microbial communities of guttation fluids were screened for biocontrol activity (68), no special criterion was used to select antagonists for mixtures. On apple, a broader spectrum of pathogens was controlled (81), and less total biomass of the antagonist was needed to control decay when antagonists were applied in mixtures instead of individually (85, 87, 114).…”

The ecophysiology of early angiosperms

“…In Arabidopsis, the epithem functions as a hub for diverse ion, amino acid and hormone transport (Largarde et al 1996;Shibagaki et al 2002;Bürkle et al 2003;Aloni et al 2003Aloni et al , 2005Pilot et al 2004;Wang et al 2004). The epithem can also add substances to the guttation fluid, such as excess calcium and proteins that protect vulnerable hydathodes from microbial and fungal attack (Fukui, Fukui & Alvarez 1999). Although gene expression in the epithem of basal angiosperms invites future study, calcium secretion and presence of an extensive epithem endocytotic system in C. japoncius suggests that nutrient and hormonal cycling is active .…”