外源酚酸对水稻种子和幼苗的化感效应

Allelopathic effects of exogenous phenolic acids composted by wheat straw on seed germination and seedling growth of rice

酚酸是还田麦秸腐解产生的主要化感物质,为明确由麦秸腐解产生的不同酚酸物质对水稻的化感效应及作用阈值,采用平板培养法和砂培法,设置不同浓度的10种外源酚酸溶液(对羟基苯甲酸、香草酸、阿魏酸、丁香酸、原儿茶酸、没食子酸、对香豆酸、芥子酸、咖啡酸和水杨酸),研究它们对水稻种子发芽和幼苗生长发育的影响。结果表明:与对照相比,10种外源酚酸均对水稻种子的萌发产生低浓度促进、高浓度抑制作用,大部分种类的酚酸溶液对水稻生物量的累积、根系活力、叶绿素含量产生低浓度促进、高浓度抑制作用,而对水稻植株体内丙二醛含量产生低浓度抑制、高浓度促进作用。酚酸溶液对水稻产生的化感效应与酚酸种类以及浓度有关,不同酚酸对水稻的作用阈值不同。

This experiment aimed to investigate allelopathic effects of phenolic acids composted by wheat straw at different concentrations on seed germination and seedling growth of rice by means of plate culture and sand culture. The results showed that the seed germination indexes in all phenolic acids treatments were promoted at lower acid concentrations and were inhibited at higher concentrations. Most of the phenolic acids played a promotive role at lower concentrations and an inhibitory role at higher concentrations in biomass accumulation, chlorophyll contents and root activity of rice as well. However on malondialdehyde content of rice, the phenolic acids presented opposite effect. The allelopathic effect of phenolic acid solution on rice was related to the kinds and concentrations of phenolic acid, and its threshold depended on the kinds.