Bae H , Roberts DP , Lim HS , Strem MD , Park SC , Ryu CM , Melnick RL , Bailey BA. Endophytic Trichoderma Isolates from Tropical Environments Delay Disease Onset and Induce Resistance Against Phytophthora capsici in Hot Pepper Using Multiple Mechanisms. Molecular Plant-Microbe Interactions

U.S. Department of Agriculture, Agricultural Research Service, Beltsville Agricultural Research Center, Beltsville, MD 20705, USA. [corrected]
Molecular Plant-Microbe Interactions (Impact Factor: 4.46). 03/2011; 24(3):336-51. DOI: 10.1094/MPMI-09-10-0221
Source: PubMed

ABSTRACT Endophytic Trichoderma isolates collected in tropical environments were evaluated for biocontrol activity against Phytophthora capsici in hot pepper (Capsicum annuum). Six isolates were tested for parasitic and antimicrobial activity against P. capsici and for endophytic and induced resistance capabilities in pepper. Isolates DIS 70a, DIS 219b, and DIS 376f were P. capsici parasites, while DIS 70a, DIS 259j, DIS 320c, and DIS 376f metabolites inhibited P. capsici. All six isolates colonized roots but were inefficient stem colonizers. DIS 259j, DIS 320c, and DIS 376f induced defense-related expressed sequence tags (EST) in 32-day-old peppers. DIS 70a, DIS 259j, and DIS 376f delayed disease development. Initial colonization of roots by DIS 259j or DIS 376f induced EST with potential to impact Trichoderma endophytic colonization and disease development, including multiple lipid transferase protein (LTP)-like family members. The timing and intensity of induction varied between isolates. Expression of CaLTP-N, encoding a LTP-like protein in pepper, in N. benthamiana leaves reduced disease development in response to P. nicotianae inoculation, suggesting LTP are functional components of resistance induced by Trichoderma species. Trichoderma isolates were endophytic on pepper roots in which, depending on the isolate, they delayed disease development by P. capsici and induced strong and divergent defense reactions.

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Available from: Choong-Min Ryu, Sep 04, 2015
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    • "Several mechanisms are reported to work in many cases of individual beneficial plantmicrobe interactions [4]. As a consequence of the interaction of these bioagents [9] or plant colonization [10] [11], the proteome and transcriptome of the plants are reported to change. Thus, it is expected that these microorganisms may reprogramme the plant defense responses, resulting in alteration of plant responses to their environment [12]. "
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    • "Endophytic microorganisms are present in various plant species and rarely produce any disease symptoms (Borneman et al. 2000; Hanada et al. 2010; Teng et al. 2010; Wang et al. 2010; Bae et al. 2011; de Siqueira et al. 2011). The asymptomatic internal colonization of healthy plant tissue by microorganisms is a widespread and well-documented phenomenon. "
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    • "(2) The antagonisms among invaders might lead to relatively low-level hostinduced immunity. Endophytes appear to trigger weak defense responses in compatible hosts (without causing obvious symptoms), whereas pathogens often have a swift and radical impact [52] [53]. (3) Limited colonization of symbionts reduces host net costs imposed by the colonizers and prevents the host from exhausting its energy supply through the redistribution of energy away from plant primary metabolism and toward defense [33] [54] [55]. "
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