Physiological roles of zinc in rice plants with reference to protein synthesis.

缺锌条件下，水稻植株出现了主要的缺锌症状，即幼叶伸长减少，膨大叶片发生微缩。后一种现象的直接原因尚未被研究。本研究测定了遮荫对缺锌水稻植株临床症状和分生组织蛋白浓度的影响。测定了锌缺乏和遮荫对水稻叶片蛋白质、游离氨基酸和过氧化物浓度及超氧化物歧化酶（SOD）活性的影响。施锌和不施遮荫均抑制了植物生长。锌无遮荫处理与遮荫处理不同，锌无遮荫处理的植株膨大叶片出现缺锌症状之一——坏死。+Zn处理的植株叶片未见坏死现象。锌缺乏对蛋白质、游离氨基酸和过氧化物浓度的影响似乎通过遮荫得到缓解。遮荫不能减轻SOD活性的降低。遮荫可以缓解锌缺乏对水稻细胞光氧化的影响。

Under Zn deficiency, some major deficiency symptoms were observed on rice plants, i.e., reduction of young leaf elongation and development of mecrosis in the expanded leaves. The direct cause of the latter phenomenon has not yet been studied. In this study, the effect of shading on clinical symptoms and protein concentration in the meristem tissues of rice plants under Zn deficiency was determined. The effects of Zn deficiency and shading on the concentration of protein, free amino acids and peroxides and the super oxide dismutase (SOD) activity in the rice leaf were also determined.Plant growth in the-Zn plots was depressed both with and without shading. One of the Zn deficiency symptoms, necrosis, was observed on the expanded leaves of the plants in the-Zn plot without shading unlike in those in the plot with shading. No necrosis was observed on the leaves of the plants in the+Zn plots. The effects of Zn deficiency on the concentration of protein, free amino acids and peroxides appears to be alleviated by shading. The depression of SOD activity was not alleviated by shading.Effect of photo-oxidation on cells under Zn deficiency appears to be alleviated by shading in rice plants.