PDF(Pubmed)
Abstract：
Blister blight (BB) disease is caused by the obligate biotrophic fungal pathogen Exobasidium vexans Massee and seriously affects the yield and quality of Camellia sinensis. The use of chemical pesticides on tea leaves substantially increases the toxic risks of tea consumption. Botanic fungicide isobavachalcone (IBC) has the potential to control fungal diseases on many crops but has not been used on tea plants. In this study, the field control effects of IBC were evaluated by comparison and in combination with natural elicitor chitosan oligosaccharides (COSs) and the chemical pesticide pyraclostrobin (Py), and the preliminary action mode of IBC was also investigated. The bioassay results for IBC or its combination with COSs showed a remarkable control effect against BB (61.72% and 70.46%). IBC, like COSs, could improve the disease resistance of tea plants by enhancing the activity of tea-plant-related defense enzymes, including polyphenol oxidase (PPO), catalase (CAT), phenylalanine aminolase (PAL), peroxidase (POD), superoxide dismutase (SOD), β-1,3-glucanase (Glu), and chitinase enzymes. The fungal community structure and diversity of the diseased tea leaves were examined using Illumina MiSeq sequencing of the internal transcribed spacer (ITS) region of the ribosomal rDNA genes. It was obvious that IBC could significantly alter the species\' richness and the diversity of the fungal community in affected plant sites. This study broadens the application range of IBC and provides an important strategy for the control of BB disease.
摘要：
水泡枯病（BB）是由专性生物营养真菌病原体Exobasidiumvexexansmassee引起的，严重影响了山茶的产量和品质。在茶叶上使用化学农药大大增加了茶叶消费的毒性风险。植物性杀真菌剂异叶阿瓦卡酮（IBC）具有控制许多作物的真菌病害的潜力，但尚未在茶树上使用。在这项研究中,通过与天然激发子壳寡糖（COSs）和化学农药吡唑醚酯（Py）的比较和组合，评价了IBC的田间防治效果，并对IBC的初步作用模式进行了研究。IBC或其与COSs的组合的生物测定结果显示出对BB的显着控制效果（61.72％和70.46％）。IBC,像COSs一样，可以通过增强茶树相关防御酶的活性来提高茶树的抗病性，包括多酚氧化酶（PPO），过氧化氢酶(CAT),苯丙氨酸氨基解酶(PAL),过氧化物酶(POD),超氧化物歧化酶（SOD），β-1,3-葡聚糖酶(Glu),和几丁质酶。使用核糖体rDNA基因的内部转录间隔区（ITS）区域的IlluminaMiSeq测序检查了患病茶叶的真菌群落结构和多样性。很明显，IBC可以显着改变受影响植物地点的物种丰富度和真菌群落的多样性。本研究拓宽了IBC的应用范围,为BB病的防治提供了重要的策略。
