The effects of boron on growth and physiological characteristics of cucumber seedlings were investigated in greenhouse with sand irrigated with modified Hoagland nutrient solution. The results showed that boron deficiency resulted in an overall inhibition of plant growth, including reduction in root, intemodes length and biomass fresh weight and dry weight, and their upper leaves curls outwards, the leaf margins turned tan. The toricity symptom in cucumber seedlings appeared in the eighth day after treated with excessive boron. Margin of the lower true leaf became tan, then turned yellow gradually and curled inwards, while the upper leaves were not significantly affected. Physiological index detections suggested that boron deficiency resulted in higher soluble sugar content and amylase activity and much lower nitrate re-ductase activity in leaves than that of CK; while excessive boron led to significantly lower soluble sugar content, amylase activity and nitrate reductase activity than that of CK.%以沙培方武利用改良Hoagland营养液研究不同浓度的硼元素对黄瓜幼苗的生长和部分生理指标的影响,结果表明:缺硼处理的黄瓜幼苗上部叶向外侧卷曲,叶缘变褐色；茎节间距明显缩短；各项外观指标明显小于正常营养液处理的植株；过量硼处理的黄瓜植株从下位叶首先出现中毒症状,在处理后的第8天第一片真叶叶缘变褐色,向内卷曲,逐渐全叶黄化,上部叶片叶色受影响较少；其各项检测指标均明显低于正常处理的植株,甚至低于缺硼处理的植株.通过生理指标的测定,发现缺硼处理叶片中可溶性糖和淀粉含量高,淀粉酶活性升高,硝酸还原酶活性降低；过量硼元素则使叶片可溶性糖含量降低,淀粉酶和硝酸还原酶活性降低.
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