鎘處理水稻 (Oryza sativa cv. Tainung 67 and Taichung native 1) 幼苗都會有明顯抑制根部的生長，在48小時鎘處理中，台中在來一號根部生長抑制較台農67號為嚴重。耐鎘品系--台農67號其根部受鎘處理後生成較多之過氧化酶，同時合成較多之木質素，而且將過氧化氫分解。而台中在來一號品系受鎘處理後，其生成的木質素較少，而且有較多的過氧化氫之累積，因此推論台中再來一號對於鎘的耐受性較差。

Cd significantly inhibited the growth of both rice cultivars. The Tainung 67 cultivar is more tolerant to Cd than Taichung 1 cultivar after 48 h incubation in CdCl2 solution. The Cd tolerant cultivar—Tainung 67’s PODs in roots might synthesize more lignin in Cd-treatments. Meanwhile, the decrease of H2O2 levels is accompanied with the enhancement of POD activity in Cd-treated tissues. PODs here might also remove excess H2O2, thus serving detoxifying role and synthesizing more lignin for protection. In Taichung 1 cultivar, the accumulation of H2O2 in Cd-treated tissues could be due to the less amount of POD enhancement induced by Cd. In response to Cd treatment, the Taichung 1 cultivar also synthesizes little lignin, and therefore is Cd-sensitive.

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