镉胁迫下低吸收水稻品种中镉的转移系数和分布特征

【目的】探索镉污染农田下不同低吸收水稻Oryza sativa品种对镉的吸收积累差异及在不同生长时期的分布特征。【方法】选取5个低镉吸收品种‘中浙优1号’‘Zhongzheyou 1’、‘中浙优8号’‘Zhongzheyou 8’、‘华浙优71’‘Huazheyou 71’、‘甬优17’‘Yongyou 17’和‘甬优1540’‘Yongyou 1540’，在浙江省丽水市景宁畲族自治县某村镉污染农田开展大田试验，探究5种低吸收品种水稻生长情况及对镉的吸收转运特征。【结果】同一水稻品种不同器官中镉的积累存在差异。在拔节期和孕穗期，镉质量分数从大到小依次为根、茎、叶、穗；在成熟期，除‘中浙优8号’外，其余水稻品种镉质量分数从大到小依次为茎、根、叶、糙米、稻壳；不同水稻品种中，‘华浙优71’水稻品种的根镉质量分数显著低于其他品种(P<0.05)，‘中浙优8号’水稻品种的茎和糙米镉质量分数显著低于其他品种(P<0.05)。同一水稻品种在不同生育期的相同器官中镉积累情况不同，根茎叶中镉质量分数从小到大依次为分蘖期、拔节期、孕穗期、成熟期。‘中浙优8号’水稻品种产量、千粒重和分蘖数均高...

Transfer coefficient and distribution characteristics of Cd in low absorption rice cultivars under Cd stress

  Objective  The purpose is to explore the difference of Cd absorption and accumulation among different low absorption rice (Oryza sativa) cultivars in Cd polluted farmland and their distribution characteristics in different growth stages.  Method  5 cultivars with low Cd absorption were selected: ‘Zhongzheyou 1’, ‘Zhongzheyou 8’,‘Huazheyou 71’,‘Yongyou 17’and‘Yongyou 1540’. A field experiment was carried out in a village of Jingning County, Lishui City, Zhejiang Province, to explore the growth and Cd uptake and transport characteristics of 5 low absorption cultivars of rice.   Result  There were differences in the accumulation of Cd in different organs of the same rice variety. At jointing stage and booting stage, the mass fraction of Cd from large to small was root, stem, leaf and ear. At the maturity stage, the Cd content of rice cultivars other than ‘Zhongzheyou 8’ was stem, root, leaf, brown rice and rice husk in descending order. Among the different rice cultivars, Cd content in the root of ‘Huazheyou 71’ was significantly lower than that of other cultivars (P＜0.05), and Cd content in the stem and brown rice of ‘Zhongzheyou 8’ was significantly lower than that of other cultivars (P＜0.05). The accumulation of Cd in the same organs of the same rice cultivars at different growth stages was different. The mass fraction of Cd in roots, stems and leaves from small to large showed as tillering stage, jointing stage, booting stage and maturity stage. The yield, 1000-grain weight and tiller number of ‘Zhongzheyou 8’ were higher than those of other cultivars. In different rice cultivars, the content of Cd in brown rice was not significantly correlated with 1000-grain weight, rice yield, soil total Cd content and soil available Cd content.   Conclusion  ‘Zhongzheyou 8’ is selected as the preferred cultivars in Cd polluted paddy field, and its low absorption and accumulation characteristics can be further discussed in the later stage. [Ch, 1 fig. 5 tab. 32 ref.]