不同水稻品种对钒的积累及化学形态

Accumulation and Chemical Forms of Vanadium in Different Rice Cultivars

通过盆栽试验,研究了钒(V)胁迫下不同品种水稻植株中钒的积累和化学形态。结果表明,不同品种水稻各器官中V的分布为根>茎>叶>子实,两种水稻品种吸收的V主要富集在根部。水稻生长期新优188水稻各器官中V的浓度均低于十优838水稻,如在V处理浓度为100 mg·kg-1时,在分蘖期、扬花期、灌浆期和成熟期,新优188水稻植株根中V含量分别为73.10、92.56、57.46、57.81μg·g-1,茎叶中为8.79、4.52、2.13、2.56μg·g-1;十优838水稻植株根中的V含量为59.14、94.93、88.59、89.70μg·g-1,茎叶中为4.64、3.66、2.29、3.24μg·g-1。推断十优838水稻较新优188水稻有较强的V吸收能力。两种水稻品种中,根部V主要以活性较低的盐酸提取态(F HCl)和醋酸提取态(FHAc)为主,茎和叶中V主要以盐酸提取态(F HCl)和水提取态(Fw)为主,认为V在水稻根部多以难溶于水的重金属磷酸盐或草酸盐而被固定,限制了水稻中V转移到茎和叶,从而避免了高浓度V对植物光合作用及其他生理过程的干扰。

Accumulation and chemical forms of vanadium in two rice cuhivars were investigated by pot experiment. It suggested that the V distribution levels in organs of two rice cultivars was in sequence as follows：root〉stem 〉leaf〉seed（rice grain）. V was accumulated mainly in roots. V concentrations in organs of the 188 species were lower than that in the 838 species. During stages of stooling, flowering, pustnlation and maturation, V concentrations in root of the 188 species were 73.10 ~g-g-l, 92.56 ~g＂ g-l, 57.46 p.g. g-＇ and 57.$1 p^g＂ g-~ respectively, in stem and leaf were 8.79 ~g＂ g-l, 4.52 ~g＂ g-l, 2.13 ~g＂ g-1 and 2.56 ~g＂ g-~ respectively, when V stress level was 100 mg-kg-~. Meanwhile V concentrations in root of the 858 species were 59.14 txg＇g-l, 94.95 ~g＇g-~, 88.59 p^g.g-I and 89.70 Ixg＇g-t respectively, and in stem and leaf were 4.64 μg.g-1, 3.66 μg .g-l, 2.29 μg-g-1and 3.24μg.g-1 respectively. It indicates that the 838 species has stronger V accumulation a- bility. V speciation in roots of the 2 rice cultivars were mainly in the chemical forms of HC1 extractable（Fna） and HAc extractable, but they were in the chemical forms of HC1 extractable and water extractable （Fw） in stems and leaves. It suggests that most V uptake into root was combined as phosphate or oxalate, which restricts its transportation from root to stem and leaf, and prevents V damaging to plant photosynthesis and other physiological process.