模拟酸雨对小麦叶片同化物、生长和产量的影响

以小麦为材料，通过大田试验研究了模拟酸雨对小麦生长和产量的胁迫效应.结果表明：酸雨胁迫对小麦产量有较大影响，当酸雨pH≤3.5时显著低于对照（P＜0.01）；当pH≤ 2.5时，小麦株高明显变矮，叶片外观出现明显的受害症状，当pH≤3.5时，叶面积和比叶 鲜质量显著降低.酸雨胁迫下，小麦叶片叶绿素a、b和类胡萝卜素含量都明显降低，但对叶绿素a的影响更显著.酸雨胁迫导致小麦叶片可溶性糖和还原糖的合成受抑，当pH≤3.5时， 受抑作用较强，且酸度越高，影响越大；酸雨胁迫下，小麦叶片的总游离氨基酸和可溶性蛋白质含量均随着酸雨酸度的增加而降低，并分别在pH≤3.5和pH≤4.5时显著低于对照（P＜0.05）.

Effects of simulated acid rain on leaf photosynthate, growth, and yield of wheat.

With winter wheat variety Yamgmai 12 as test object, a field experiment was conducted to study the stress of simulated acid rain on its growth and development. The results showed that simulated acid rain had considerable effect on wheat growth and yield. When the pH of acid rain was ≤3.5, the growth of leaf area as well as the mass of fresh leaf per unit area declined greatly, and the yield was significantly lower than CK. When pH was ≤2.5, the plant height was obviously lowered, and the visible injury on leaf surface was observed. Under acid rain stress, the contents of leaf chlorophyll a, chlorophyll b, and carotenoid, especially chlorophyll a, decreased obviously. Acid rain also suppressed the synthesis of soluble sugar and reduced sugar, and the suppression was stronger at pH≤3.5, and became much stronger with increasing acidity. The total free amino acid and soluble protein contents in leaves decreased with increasing acidity, and were significantly lower than CK when the pH was ≤3.5 and ≤4.5, respectively.