https://search.dev.ndltd.org/etd/lincoln/oai:researcharchive.lincoln.ac.nz:10182/17559
type: CreativeWork
name: Tea (Camellia sinensis (L.) O. Kuntze) plant productivity and protection with microbial stimulants : A thesis submitted in partial fulfilment of the requirements for the Degree of Doctor of Philosophy at Lincoln University
description: While there is an increasing consumption of organic tea as a healthy beverage, tea growers are struggling to produce tea without agrochemicals. To help find solutions for this challenge, a study was conducted on bioprospecting microbes to potentially create bioprotectant products against tea pathogens in Sri Lanka and biopromotion products in organic tea cultivation in New Zealand. Blister blight, caused by Exobasidium vexans, is a major tea disease in Sri Lanka. Investigation of this obligate parasite has been limited due to a lack of successful artificial culture media. Potato Dextrose Agar medium was modified with five different tea extracts to investigate the best growth media which can facilitate dual-culture assays among indigenous endophytes and tea pathogens. Brown blight caused by Colletotrichum camelliae was also tested in this study. Potato dextrose agar ammended with either 25% fresh or dried tea leaf infusion incorporated, tea extact agar (TEA) media were successful for in-vitro cultivation of tea pathogens. During the research, Nigespora sp. was arbitrarily identified as a leaf blight pathogen on tea in Sri Lanka for the first time. Twenty indigenous fungi and seven bacterial endophytes were identified from the tea phyllosphere in Sri Lanka. More than 50% of them exhibited biocontrol potential against the economically important tea pathogens in-vitro while Trichoderma harzianum provided the best inhibition. Seven indigenous fungal and four bacterial genera were identified from soil and leaf samples from a tea plantation in New Zealand and used for biopromotion bioassays on young tea plants grown under glasshouse conditions. Indigenous Hypocrea lixii provided the most significant biostimulation, than its exogenous anamorph; T. harzianum, which was tested representing the new taxonomic concept of H. lixii and T. harzianum as two individual species (previously classified as teleomorph and anamorph of the same species). This study isolated H. lixii for the…
abstract: While there is an increasing consumption of organic tea as a healthy beverage, tea growers are struggling to produce tea without agrochemicals. To help find solutions for this challenge, a study was conducted on bioprospecting microbes to potentially create bioprotectant products against tea pathogens in Sri Lanka and biopromotion products in organic tea cultivation in New Zealand. Blister blight, caused by Exobasidium vexans, is a major tea disease in Sri Lanka. Investigation of this obligate parasite has been limited due to a lack of successful artificial culture media. Potato Dextrose Agar medium was modified with five different tea extracts to investigate the best growth media which can facilitate dual-culture assays among indigenous endophytes and tea pathogens. Brown blight caused by Colletotrichum camelliae was also tested in this study. Potato dextrose agar ammended with either 25% fresh or dried tea leaf infusion incorporated, tea extact agar (TEA) media were successful for in-vitro cultivation of tea pathogens. During the research, Nigespora sp. was arbitrarily identified as a leaf blight pathogen on tea in Sri Lanka for the first time. Twenty indigenous fungi and seven bacterial endophytes were identified from the tea phyllosphere in Sri Lanka. More than 50% of them exhibited biocontrol potential against the economically important tea pathogens in-vitro while Trichoderma harzianum provided the best inhibition. Seven indigenous fungal and four bacterial genera were identified from soil and leaf samples from a tea plantation in New Zealand and used for biopromotion bioassays on young tea plants grown under glasshouse conditions. Indigenous Hypocrea lixii provided the most significant biostimulation, than its exogenous anamorph; T. harzianum, which was tested representing the new taxonomic concept of H. lixii and T. harzianum as two individual species (previously classified as teleomorph and anamorph of the same species). This study isolated H. lixii for the…
author: Patti Dorage, Prashansani Madhusha Darshani Silva
language: en
keywords: Exobasidium vexans, Colletotrichum camelliae, Nirospora sp. on tea, Trichoderma, Trichoderma harzianum, Trichoderma atroviride, Hypocrea lixii, DNA metabarcoding, bioprospecting, biostimulants, biocontrol, biopromotion, tea, tea diseases, organic tea, indigenous microbes, soil microbiome, next-generation sequencing (NGS), host-specific culture media, Sri Lanka, tea pathogens, ANZSRC::310805 Plant pathology
license: https://researcharchive.lincoln.ac.nz/pages/rights
date published: 2024
date modified: 2026-07-24T02:50:42Z
provider: Lincoln University
publisher: Networked Digital Library of Theses and Dissertations
type: WebPage
source organization: Lincoln University

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property ID: Handle
value: https://hdl.handle.net/10182/17559