Page 6 - 《广西植物》2025年第10期
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1 7 3 6                                广  西  植  物                                         45 卷
                 Abstract: Virus infections plants lead to abnormal metabolism of pigments in leavesꎬ flowers and fruits. For instanceꎬ
                 tomato spotted wilt virus (TSWV) infection can cause purple veins in tomato leavesꎬ but the mechanism of the virus on
                 the pigment metablism of host plants remains unclear. The purple ̄veined leaves of Solanum lycopersicum ‘strawberry
                 tomato’ plants infected with TSWV of different disease severities were used as experimental materials. We analyzed
                 lesions of chloroplast ultrastructureꎬ and plastid pigment substance content and evaluated the correlation of these
                 parameters on purple ̄veined tomato leaves. The results were as follows: (1) The degree of deformity of the chloroplast
                 structure in TSWV ̄infected tomato purple ̄veined leaves increased graduallyꎬ the number and volume of plastoglobules
                 increasedꎬ the number of grana decreasedꎬ and the contents of chlorophyll a and bꎬ and total chlorophyll also
                 decreased. (2) The total chlorophyll content was negatively correlated with the number of plastoglobules and positively
                 correlated with the number of grana. (3) The expression levels of genes encoding enzymes related to the carotenoid
                 synthesis pathway (ZEPꎬ PDSꎬ and LCYEꎬ etc.) and the pigment transcription regulatory factors AP2aꎬ MYB12 and
                 PIF1a were significantly decreased. (4) The expression of N gene copy caused changes in the chloroplast ultrastructure
                 and pigment synthesis anabolism in TSWV ̄infected tomato leavesꎬ consequentlyꎬ it led to the appearance of purple veins
                 on the leaves. Above results provide a foundation for further research on the mechanism of color symptom formation after
                 TSWV infects host plants. This study is the first to reveal the relationship between chloroplast ultrastructural changes and
                 pigment substances in tomato purple ̄veined leaves caused by TSWV infectionꎬ regulatory factors involved in pigment
                 metabolism may be new targets of TSWV pathogenesisꎬ providing a new direction for the development of TSWV ̄resistant
                 tomato cultivation through targeted gene editing.
                 Key words: tomato spotted wilt virus ( TSWV )ꎬ tomatoꎬ purple ̄veined leavesꎬ chloroplastꎬ pigmentꎬ
                 carotenoidꎬ plastoglobule



                病毒侵染引起寄主植物在激素水平和色素水                            病毒基因组片段(小、中、大) 组成ꎬ编码 5 种蛋白ꎬ
            平上的响应ꎬ使寄主叶片和果实出现多种病变特                              即核衣壳蛋白( N)、两个糖蛋白( Gn / Gc)、复制和
            征ꎬ如叶片卷缩、黄化、环斑、紫脉及果实颜色病变                            转录病毒基因组 RNA 依赖的 RNA 聚合酶(RdRp)
            等ꎮ 有关病毒侵染后寄主植株激素水平的响应变                             及运动相关非结构蛋白( NSm)ꎮ TSWV 侵染番茄
            化已有报道ꎬ如水杨酸( salicylic acidꎬSA) 是番茄                 后早期症状表现为叶脉发紫ꎬ中期表现为紫脉和

            植株 对 番 茄 斑 萎 病 毒 ( tomato spotted wilt virusꎬ      紫叶、顶叶萎蔫ꎬ后期表现为植株萎蔫、枯死ꎬ果实
            TSWV)基本抗性的重要组成部分ꎬ番茄植株抵御                            黄化、白化或绿色僵果ꎬ推测 TSWV 侵染番茄后叶

            TSWV 侵 染 依 赖 SA 途 径 ( López ̄Gresa et al.ꎬ          片及果实的颜色病变与植株色素合成代谢有关ꎮ
            2016)ꎻ 南 方 水 稻 黑 条 矮 缩 病 毒 ( southern rice         番茄是重要的蔬菜和水果ꎬ含有丰富的类胡萝卜
            black ̄streaked dwarf virusꎬSRBSDV) 的 SP8 蛋白能       素、黄酮类化合物和维生素ꎬ这些化合物不仅参与
            与茉莉酸(jasmonic acidꎬJA) 信号途径的关键成分                   植株叶片和果实颜色的变化ꎬ而且还参与植株的
            中间蛋白 25( MED25) 互作减弱 JA 途径ꎬ从而促                     抗生物胁迫或非生物胁迫ꎮ 目前ꎬ关于病毒侵染
            进病毒侵染( Zhao & Liꎬ 2021)ꎬ而有关病毒侵染                    后对番茄叶片质体色素代谢及调控影响的研究尚
            后寄主植株色素合成代谢水平的变化和响应机制                              未见报道ꎮ
            还未明 确ꎮ 番 茄 斑 萎 病 毒 属 于 布 尼 亚 病 毒 目                     质体是植物细胞中关键的多功能代谢工厂且
            (Bunyavirales)番茄斑萎病毒科( Tospoviridae) 正番            具有半自主性ꎬ其内部精细的超微结构对质体的
            茄斑萎病毒属( Orthotospovirus) 病毒ꎬ在全球范围                  形成和功能具有重要意义( Satoꎬ 2006)ꎮ 植物细
            内广泛分布ꎬ侵染为害 84 科 1 090 多种植物ꎬ被列                      胞中的质体通常分为叶绿体( 光合作用)、有色体
            为全球十大植物病毒之一(Scholthof et al.ꎬ 2011)ꎮ               (色素的合成和储存) 和白色体ꎬ它们之间可以相
            TSWV 是全球番茄的重要病毒病原ꎬ近年来已在我                           互转化ꎮ 质体叶绿体作为光合作用的细胞器ꎬ内
            国 20 多个省(区、市) 快速发生蔓延ꎬ在感病番茄                         部结构的研究最为深入ꎮ 在所有高等植物中都发
            品种上引起毁灭性损失ꎮ TSWV 的基因组由 3 个                         现了呈椭圆形或双凸形的叶绿体ꎬ在叶绿体内部
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