Research Institute of Subtropical Forestry, Chinese Academy of Forestry, Fuyang, Hangzhou 311400, China.
J Agric Food Chem. 2023 Apr 12;71(14):5812-5822. doi: 10.1021/acs.jafc.2c08434. Epub 2023 Mar 30.
Pecan, (Wangenh.) K. Koch, is an important dried fruit and woody oil tree species grown worldwide. With continuous expansion of pecan cultivation, the frequency and scope of diseases, especially black spot disease, are increasing, damaging trees and reducing yields. In this study, the key factors in resistance to black spot disease () were investigated between the high-resistance pecan variety "Kanza" and the low-resistance variety "Mahan". Leaf anatomy and antioxidase activities confirmed much stronger resistance to black spot disease in "Kanza" than in "Mahan". Transcriptome analysis indicated that the increased expression of genes associated with defense response, oxidation-reduction, and catalytic activity was involved in disease resistance. A connection network identified a highly expressed hub gene (CIL1242S0042), which might participate in redox reactions to affect disease resistance. Overexpression of in tobacco inhibited enlargement of necrotic spots and increased disease resistance. Overall, the expression of differentially expressed genes differed in pecan varieties with different levels of resistance to infection. In addition, the hub genes associated with black spot resistance were identified and the functions clarified. The in-depth understanding of resistance to black spot disease provides new insights for early screening of resistant varieties and molecular-assisted breeding in pecan.
山核桃（Wangenh.）K. Koch，是一种重要的干果树种和木本油料树种，在全球范围内广泛种植。随着山核桃种植面积的不断扩大，病害的发生频率和范围，尤其是黑斑病，也在不断增加，对树木造成损害并降低产量。本研究在高抗品种“堪萨斯”和低抗品种“马罕”之间，调查了黑斑病抗性的关键因素。叶片解剖结构和抗氧化酶活性表明，“堪萨斯”比“马罕”对黑斑病具有更强的抗性。转录组分析表明，与防御反应、氧化还原和催化活性相关的基因表达增加与抗病性有关。连接网络鉴定出一个高表达的枢纽基因（CIL1242S0042），它可能参与氧化还原反应，从而影响抗病性。在烟草中过表达该基因可抑制坏死斑的扩大并提高抗病性。总之，不同抗病性山核桃品种对的感染表现出不同的差异表达基因。此外，还鉴定了与黑斑病抗性相关的枢纽基因，并阐明了它们的功能。对黑斑病抗性的深入了解为山核桃早期筛选抗性品种和分子辅助育种提供了新的思路。
