不同pH值对裂叶牵牛种子萌发和幼苗生长的影响

研究了pH值对裂叶牵牛种子萌发和幼苗生长的影响,结果表明：pH值为3～4的酸性水溶液可缩短裂叶牵牛的种子萌发时间,并促进种子萌发.随着pH值的降低,裂叶牵牛幼苗的根长、苗高及鲜质量受到的抑制作用增大;pH值对裂叶牵牛叶绿素b的影响高于叶绿素a;随着pH值的降低,叶绿素a/b增大.pH值对裂叶牵牛幼苗根、茎、叶的可溶性糖和MDA（丙二醛）含量的影响存在差异.pH值降低使裂叶牵牛的茎及根中的可溶性糖和MDA含量增加.当pH值为4时,裂叶牵牛叶中的可溶性糖和MDA含量均最高;当pH值高于或低于4时,裂叶牵牛叶的可溶性糖和MDA含量均下降.

Influences of Different pH Values on Seed Germination and Seedling Growth of Pharbitis nil

We investigated influences of different pH values on the germination,seedling growth and physiological-biochemical indexes of Pharbitiis nil. The results showed that pH values of 3 and 4 cut down germination days and promoted germination ratio. Alone reduced pH values,the inhibitory effects on root length,seedling height and fresh weight increased. And degradation effects of pH values on chlorophyll b were higher than on chlorophyll a. The values of chlorophyll a/b increased gradually alone decreasing pH values. There were differences between contents of soluble sugar and MDA （malondialdehydrate） in roots,stems and leaves of P. nil under different pH values. Alone reduced pH values,contents of soluble sugar and MDA in stems and leaves of P. nil increased. The contents of soluble sugar and MDA in leaves of P. nil were high. When pH value was higher or lower than 4, the contents of soluble sugar and MDA in leaves of P. nil all decreased.