Zhang Zhenwu, Zhang Ye, Wang Yun, Fan Jiaqi, Xie Zhihua, Qi Kaijie, Sun Xun, Zhang Shaoling
Center of Pear Engineering Technology Research, National Key Laboratory of Crop Genetics & Germplasm Enhancement and Utilization, College of Horticulture, Nanjing Agricultural University, Nanjing 210095, China; College of Agricultural, Jinhua Polytechnic, Jinhua, China.
Center of Pear Engineering Technology Research, National Key Laboratory of Crop Genetics & Germplasm Enhancement and Utilization, College of Horticulture, Nanjing Agricultural University, Nanjing 210095, China.
Plant Sci. 2023 Apr;329:111603. doi: 10.1016/j.plantsci.2023.111603. Epub 2023 Jan 26.
Pear ring rot, a fungal disease caused by Botryosphaeria dothidea (B. dothidea), is one of the most damaging diseases in pear production, affecting fruit yield and causing economic losses. It is not clear whether dopamine, one of the catecholamines, has any role in pear ring rot resistance. In this study, we found that dopamine treatment of B. dothidea resulted in a significant upregulation of PbrTYDC expression compared to HO treatment (control) and reduced the levels of Hydrogen Peroxide (HO) and Superoxide Anion (O), increased Peroxidase (POD), Catalase (CAT), Superoxide Dismutase (SOD) and Phenylalanine Ammonia-Lyase (PAL) activities, and induced a significant upregulation of related gene expression. Dopamine treatment promoted the oxidationreduction capacity of the AsA-GSH cycle to scavenge Reactive Oxygen Species (ROS), increased the expression of autophagy-related genes and the accumulation of autophagic structures, and enhanced autophagic activity. Silencing PbrTYDC and PbrATG8 in pear increased HO and·O, decreased POD, CAT and SOD activities and reduced resistance to B. dothidea, which was restored by dopamine treatment. In conclusion, exogenous dopamine enhances resistance to B. dothidea by increasing the antioxidant capacity and autophagic activity of pears, and this study provides new insights for subsequent studies on B. dothidea as well as autophagy.
梨轮纹病是由葡萄座腔菌（B. dothidea）引起的一种真菌病害，是梨生产中危害最大的病害之一，影响果实产量并造成经济损失。目前尚不清楚儿茶酚胺之一的多巴胺在梨对轮纹病的抗性中是否起作用。在本研究中，我们发现用多巴胺处理葡萄座腔菌后，与水处理（对照）相比，梨酪氨酸脱羧酶（PbrTYDC）的表达显著上调，过氧化氢（HO）和超氧阴离子（O）水平降低，过氧化物酶（POD）、过氧化氢酶（CAT）、超氧化物歧化酶（SOD）和苯丙氨酸解氨酶（PAL）活性增加，并且相关基因表达显著上调。多巴胺处理促进了抗坏血酸-谷胱甘肽循环的氧化还原能力以清除活性氧（ROS），增加了自噬相关基因的表达和自噬结构的积累，并增强了自噬活性。在梨中沉默PbrTYDC和PbrATG8会增加HO和·O，降低POD、CAT和SOD活性，并降低对葡萄座腔菌的抗性，而多巴胺处理可恢复这种抗性。总之，外源多巴胺通过提高梨的抗氧化能力和自噬活性来增强对葡萄座腔菌的抗性，本研究为后续关于葡萄座腔菌以及自噬的研究提供了新的见解。
