Effects of Mn-Cd antagonistic interaction on Cd accumulation and major agronomic traits in rice genotypes by different Mn forms

• Published in: Plant growth regulation 2017-06, Vol.82 (2), p.317-331
• Main Authors: Huang, Qi-na, An, Hua, Yang, Yong-jie, Liang, Yan, Shao, Guo-sheng
• Format: Article
• Language: English
• Subjects: Accumulation; Agriculture; Biomedical and Life Sciences; Cadmium; Genotypes; Hydroponics; Life Sciences; Manganese; Original Paper; Plant Anatomy/Development; Plant Physiology; Plant Sciences; Roots; Shoots; Toxicity
• ISSN: 0167-6903; 1573-5087
• DOI: 10.1007/s10725-017-0261-8

The antagonistic interaction between Mn (Manganese) and Cd (Cadmium) was studied in Milyang 46 and Zhenshan 97B rice varieties in relation to Cd tolerance and accumulation in hydroponics. Additionally, a new method controlling Cd uptake and accumulation was established with Jinzao 47 and Zhongjiazao 32 rice varieties with similar growth periods in a soil culture system by application of different forms of Mn. (1) In hydroponics, the results showed that MnSO 4 (9.1 and 91 µM) and EDTA·Na 2 Mn (9.1 µM) significantly alleviated Cd toxicity at high levels of Cd (1.0 and 5.0 µM), and Cd accumulation in roots and root plates were significantly reduced in contrast to shoots, but 91 µM EDTA·Na 2 Mn posed serious Mn toxicity in both rice genotypes, and increasing Cd levels could reduce Mn accumulation. (2) In a soil culture system, for rice shoots, roots and grains, soil application of MnSO 4 significantly increased Cd accumulation, but EDTA·Na 2 Mn greatly decreased Cd accumulation and ameliorated Cd-induced pre-senescence. Furthermore, foliar application of MnSO 4 or EDTA·Na 2 Mn reduced Cd accumulation in grains but increased Cd accumulation in shoots at the mature stage. Our data suggest there is significant interaction between Mn and Cd in relation to the forms of Mn. Alleviation of MnSO 4 on Cd toxicity, and Cd accumulation in plants occurred only under Mn deficiency. Additionally, EDTA·Na 2 Mn is a chelated Mn complex, relatively more stable than MnSO 4 , and could maintain a high level of Mn 2+ for a longer period in solution; therefore, EDTA·Na 2 Mn instead of MnSO 4 could be a practical way to control Cd accumulation in rice.