Natural variation of diterpenoid phytoalexins in cultivated and wild rice species
Natural variation of diterpenoid phytoalexins in cultivated and wild rice species
复制标题
DOI：
10.1016/j.phytochem.2020.112518
复制
发表时间：
2020-12-01
期刊：
影响因子：
3.8
通讯作者：
Ishihara, Atsushi
中科院分区：
文献类型：
--
作者：
Kariya, Keisuke;Ube, Naoki;Ishihara, Atsushi
水稻（Oryza sativa）叶片积累植物抗毒素以响应病原体的攻击。水稻中的主要植物抗毒素是二萜类化合物，如momilactones、phytocassane和oryzalexins。我们分析了来自世界水稻核心保藏中心（WRC）的品种的UV光照射叶片中的momilactones A和B以及phytocassanes A和D的丰度。这两种类型的植物抗毒素检测在大多数品种，但是，它们的积累量变化很大，从品种到品种。在粳稻品种中，苦瓜内酯A和B的含量均高于籼稻品种。然而，积累量的phytocassanes没有相关的亚种的差异。此外，还观察到7个野生稻品种的植物抗毒素含量存在差异。在对来自世界资源中心的栽培品种中的毛霉内酯A进行分析的过程中，在'Jagelon'和'Basilanon'中检测到两种未知化合物。我们从紫外光照射的叶片中分离得到了这些化合物，并确定了它们的结构。从'Jagelon'中分离的化合物是具有松香烷骨架的momilactone A的异构体，而从'Basilanon'中分离的化合物是二脱氢phytocassane A;这些化合物被称为oryzalactone和phytocassane G。水稻内酯积累在只有三个品种，而phytocassane G积累在几乎所有的品种从WRC。这些结果表明，存在着很大的自然变异的组成在水稻中的植物抗毒素。
Rice (Oryza sativa) leaves accumulate phytoalexins in response to pathogen attack. The major phytoalexins in rice are diterpenoids such as momilactones, phytocassanes, and oryzalexins. We analyzed the abundance of momilactones A and B and phytocassanes A and D in UV-light-irradiated leaves of cultivars from the World Rice Core Collection (WRC). Both types of phytoalexins were detected in most cultivars; however, their accumulated amounts varied greatly from cultivar to cultivar. The amounts of momilactones A and B tended to be higher in japonica cultivars than those in indica cultivars. However, the accumulated amounts of phytocassanes were not related to differences in subspecies. In addition, variation in phytoalexin content was observed for seven wild rice species. During the analysis of momilactone A in cultivars from the WRC, two unknown compounds were detected in 'Jaguary' and 'Basilanon' . We isolated these compounds from UV-light-irradiated leaves and determined their structures. The compound isolated from 'Jaguary' was an isomer of momilactone A that had an abietane skeleton, while that from 'Basilanon' was di-dehydrogenated phytocassane A; these compounds were denoted as oryzalactone and phytocassane G. Oryzalactone accumulated in only three cultivars, whereas phytocassane G accumulated in almost all of the cultivars from the WRC. These findings indicate the existence of large natural variation in the phytoalexin composition in rice.