黑腐会给冬枣产业带来巨大的经济损失。本研究的目的是探讨L-蛋氨酸(Met)处理增强冬枣果实对黑腐病的抗性的潜在机制。结果表明,Met的应用显着减少了冬枣果实的病变直径和腐烂发生率。处理4天后,Met处理的枣中的过氧化物酶(POD)活性是对照枣的3.06倍。到第8天,苯丙氨酸解氨酶(PAL)的活性,经Met处理的枣中的几丁质酶(CHI)和β-1,3-葡聚糖酶(GLU)激增至顶峰,对照组为1.39、1.22和1.52倍,分别。在存储结束时,总黄酮和总酚含量比对照组保持1.58和1.06倍。基于代谢组学和转录组学分析,Met处理上调了6种关键差异表达代谢物(DEM)(琥珀酸,反式阿魏酸,水杨酸,飞燕草颜料,(S)-脱落酸,和橙皮苷-7-新橙皮苷),12个关键差异表达基因(DEGs)(PAL,CYP73A,COMT,4CL,CAD,POD,UGT72E,ANS,CHS,IAA,TCH4和PR1),参与苯丙素生物合成途径,类黄酮生物合成途径和植物激素信号转导途径。进一步的分析表明,大多数的酶,本研究中的DEM和DEG与抗氧化和抗病性有关。因此,Met处理通过提高抗氧化能力和引发防御反应来增强冬枣果实的抗病性。本研究可为利用Met防治冬枣采后黑腐病提供理论支持。
Black rots lead to great economic losses in winter jujube industry. The objective of this research was to delve into the underlying mechanisms of enhanced resistance of winter jujube fruit to black rot by L-Methionine (Met) treatment. The findings revealed that the application of Met significantly curtailed lesion diameter and decay incidence in winter jujube fruit. The peroxidase (POD) activity in the Met-treated jujubes was 3.06-fold that in the control jujubes after 4 d of treatment. By day 8, the activities of phenylalanine ammonia-lyase (PAL), chitinase (CHI) and β-1,3-glucanase (GLU) in the Met-treated jujubes had surged to their zenith, being 1.39, 1.22, and 1.52 times in the control group, respectively. At the end of storage, the flavonoid and total phenol content remained 1.58 and 1.06 times than that of the control group. Based on metabolomics and transcriptomics analysis, Met treatment upregulated 6 key differentially expressed metabolites (DEMs) (succinic acid, trans-ferulic acid, salicylic acid, delphinium pigments, (S)-abscisic acid, and hesperidin-7-neohesperidin), 12 key differentially expressed genes (DEGs) (PAL, CYP73A, COMT, 4CL, CAD, POD, UGT72E, ANS, CHS, IAA, TCH4 and PR1), which were involved in phenylpropanoid biosynthesis pathway, flavonoid biosynthesis pathway and plant hormone signal transduction pathway. Further analysis revealed that the most of the enzymes, DEMs and DEGs in this study were associated with both antioxidant and disease resistance. Consequently, Met treatment enhanced disease resistance of winter jujube fruit by elevating antioxidant capacity and triggering defense response. This study might provide theoretical support for utilizing Met in the management and prevention of post-harvest black rot in winter jujube.