鎘處理對蕹菜微觀結構之影響

Effects of Cadmium Treatment on the Microscopic Structures of Water Convolvulus (Ipomoea aquatica, Forsk)

蕹菜經鎘處理後，新葉產生黃化現象，類似缺鐵之症狀。在顯微鏡下觀察時，鎘處理和缺鐵對葉片之組織或葉綠體結構所產生的影響不甚相似，但皆可因外加鐵而得到改善；但根部皮層因鎘受到傷害，而鐵缺乏對之無影響。試驗資料顯示，鎘可誘導空心菜植株缺鐵，但其影響作用機制似有所不同。

Water convolvulus after cadmium treatment produced symptom (chlorosis) similar to that of iron deficiency. However, the effects of cadmium toxicity and iron deficiency on plant tissues and chloroplast structure were not identical. Chlorosis of young leaves induced either by cadmium or iron deficiency can be relieved to some extent by the addition of iron to the medium or through foliar application. On the other hand, root cortex of water convolvulus was damaged by cadmium while iron deficiency had no effect. Results indicated that cadmium could induce iron deficiency in water convolculus but the mechanism of injury seemed to be different at cellular level.