钒在不同蔬菜体内的吸收转运及其亚细胞分布  

Accumulation,Translocation and Subcellular Distribution of Vanadium in Brassica juncea and Brassica Chinensis

作　　者：侯明[1] 胡存杰[1] 郭零[1] 

机构地区：[1]桂林理工大学化学与生物工程学院,广西桂林541004

出　　处：《核农学报》2014年第3期492-499,共8页Journal of Nuclear Agricultural Sciences

基　　金：国家自然科学基金项目(41161076);广西自然科学基金项目(2011GXNSFA018045);广西环境工程与保护评价重点实验室研究基金项目(桂科能0701k013)

摘　　要：通过盆栽培养试验结合差速离心技术，研究了钒（Ⅴ）在芥菜（Brassica juncea）和小白菜（Brassica chinensis）的叶片、叶柄和根系中的亚细胞分布和积累。研究表明，Ⅴ在芥菜和小白菜不同器官中的含量和分配比例大小依次为：根系 〉叶片 〉叶柄，不同蔬菜地下部和地上部积累的Ⅴ含量和分配比例有明显差异，芥菜吸收积累Ⅴ的能力大于小白菜。随着Ⅴ处理浓度的增加，芥菜和小白菜富集系数（BCF）增加，而转运系数（TF）减小，表明蔬菜对Ⅴ有一定的富集能力，两种蔬菜转运Ⅴ的能力降低，其积累的Ⅴ主要富集在植物根部，可减轻过量Ⅴ对可食部分的伤害。Ⅴ在植株各器官的亚细胞分布主要为细胞壁和含核蛋白的细胞可溶性组分，在芥菜和小白菜根系中，两种组分的Ⅴ含量之和占总量的 73.4%~78.6%，在叶柄中占总量的74.9%~79.8%，叶片中为86.6%~93.2%，而Ⅴ在细胞核、线粒体和叶绿体两种细胞器中的分配较少，根系为21.4%~26.6%，叶柄为20.1%~25%，叶片为6.8%~13.4%。随着Ⅴ处理浓度的增加，蔬菜根系和叶片中Ⅴ在细胞壁的分配增加，在含核蛋白的细胞可溶性组分的分配减少；在叶柄中Ⅴ在含核蛋白的细胞可溶性组分的分配增加，细胞核和线粒体叶绿体两组分的分配减小。在不同Ⅴ浓度处理下，芥菜较小白菜对Ⅴ有较强的耐性，而细胞壁固持和可溶性组分的液泡区隔化可能是蔬菜耐Ⅴ的主要机制。Brassica juncea and Brassica chinensis plants were subjected to varying doses of Ⅴ for 40 days to investigate the effects on uptake, tissue accumulation and subcellular distribution of Ⅴ in the two cultivars by differential centrifugation. The distribution level of Ⅴ in plant organs was in sequence as follows： root 〉leaf 〉petiole. There was a significant difference of Ⅴ accumulation and distribution in roots and aerial parts of the two vegetables： Ⅴ level in Brassica juncea was more than that in Brassica chinensis. With Ⅴ stress level increasing, the bioconcentration factors（BCF） of the two vegetables increased, but their transfer coefficients（TF） decreased, indicating that they have certainability of Ⅴ enrichment. Transporting less Ⅴ from roots to aerial parts by the vegetables results in that more Ⅴ was enriched in roots, reducing the damage of excessive Ⅴ to the aerial parts of vegetables. Ⅴ subcellular distribution in plant organs was mainly localized in cell walls and soluble fractions. Plant fractionation indicated that 73.4%~78.6% of Ⅴ in roots, 74.9%~79.8% in petioles, and 86.6%~93.2% in leaves was accumulated in cell walls and soluble fractions. For roots and leaves, Ⅴ accumulation increased in cell wall but decreased in soluble fractions, with Ⅴ level increasing. For petioles, Ⅴ accumulation increased in soluble fractions but decreased in cell nucleus, mitochondria and chloroplasts. At all doses of Ⅴ stress, Brassica juncea had higher tolerance to Ⅴ than Brassica chinensis does. It suggested that there was a joint contribution of cell walls and vacuoles in Ⅴ accumulation and detoxification in Brassica junce and Brassica chinensis.

关 键 词：钒 蔬菜 积累 转运 亚细胞分布 

分 类 号：S63[农业科学—蔬菜学]