Biochemical analysis of plant protection afforded by a nonpathogenic endophytic mutant of Colletotrichum magna

Journal Article · Mon Feb 01 04:00:00 EST 1999 · Plant Physiology; (Bethesda)

DOI:https://doi.org/10.1104/pp.119.2.795· OSTI ID:6279795

Redman, R S; Rodriguez, R J ^[1]; Clifton, D R; Morrel, J; Brown, G ^[2]; Freeman, S ^[3]

---

1. Geological Survey, Seattle, WA (United States) Univ. of Washington, Seattle, WA (United States). Dept. of Botany
2. Geological Survey, Seattle, WA (United States)
3. Volcani Center, Bet Dagan (Israel). Dept. of Plant Pathology

A nonpathogenic mutant of Colletotrichum magna (path-1) was previously shown to protect watermelon (Citrullus lanatus) and cucumber (Cucumis sativus) seedlings from anthracnose disease elicited by wild-type C. magna. Disease protection was observed in stems of path-1-colonized cucurbits but not in cotyledons, indicating that path-1 conferred tissue-specific and/or localized protection. Plant biochemical indicators of a localized and systemic (peroxidase, phenylalanine ammonia-lyase, lignin, and salicylic acid) plant-defense response were investigated in anthracnose-resistant and-susceptible cultivars of cucurbit seedlings exposed to four treatments: (1) water (control), (2) path-1 conidia, (3) wild-type conidia, and (4) challenge conditions (inoculation into path-1 conidia for 48 h and then exposure to wild-type conidia). Collectively, these analyses indicated that disease protection in path-1-colonized plants was correlated with the ability of these plants to mount a defense response more rapidly and to equal or greater levels than plants exposed to wild-type C. magna alone. Watermelon plants colonized with path-1 were also protected against disease caused by Colletotrichum orbiculare and Fusarium oxysporum. A model based on the kinetics of plant-defense activation is presented to explain the mechanism of path-1-conferred disease protection.

• Sponsoring Organization: NSF; DOE; DOA; National Science Foundation, Washington, DC (United States); USDOE, Washington, DC (United States); Department of Agriculture, Washington, DC (United States)
• OSTI ID: 6279795
• Journal Information: Plant Physiology; (Bethesda), Journal Name: Plant Physiology; (Bethesda) Vol. 119:2; ISSN PLPHAY; ISSN 0032-0889
• Country of Publication: United States
• Language: English

Related Subjects

553000* -- Agriculture & Food Technology
60 APPLIED LIFE SCIENCES
CROPS
CUCUMBERS
DISEASE RESISTANCE
FOOD
FUNGI
MAGNOLIOPHYTA
MAGNOLIOPSIDA
MATHEMATICAL MODELS
PLANT DISEASES
PLANTS
VEGETABLES