正茬与连作大豆根系分泌物差异及对大豆幼苗生长的影响

采用GC-MS分析法,检测正茬、连作大豆根系分泌物成分,比较其差异,测定分泌物对大豆种子萌发和初生根生长的影响。结果表明,两种分泌物相同的成分有邻苯二甲酸、乙苯、苯乙烯、丙三醇、二十四烷、邻苯二甲酸二异丁酯等。连作大豆根系分泌物提取物中,(E)-2-丁烯酸、7,9-二甲基-十六烷、甲基-丁二酸、2-乙基-1-十二醇、二十烷、十一醛相对含量较高,而且这些物质未在正茬大豆分泌物中检测到,这些物质在大豆连作中的化感作用有待进一步研究。无论是正茬还是连作大豆根系分泌物对大豆种子的萌发和初生根生长都表现出抑制作用,抑制作用随浓度的增大而增大。在相同浓度处理下,连作大豆根系分泌物对种子萌发和初生根生长的抑制作用要高于正茬。

Difference effect of rotation and continuous soybean root secretion on seedling growth of soybean

This paper mainly detected components of root secretion of rotation and continuous soybean by GC-MS analysis, contrasted the differences of root secretion between rotation and continuous soybean, determined effects of root secretion on the soybean seed germination and the primary root growth. The results showed that the same ingredients among two secretions were phthalic acid, ethyl benzene, styrene, glycerin, lignocerane, and so on. In the extractive of secretions of con-tinuous soybean, the relatively high components were (E)-2-butenoic acid, 7-9-dimethyl-hexadecane, methyl-succinic acid, 2-ethyl-1-lauryl alcohol, eicosane, undecanal, which detected in the soybean rotation. The allelopathy of such materials in continuous soybean needed to be further studied. Such two secretions both showed inhibition to soybean seed germination and primary root growth. With the concentration increased, the inhibition strengthened. At the same concentration, the root secretion of continuous soy-bean was more inhibitory against seed germination and primary root growth than that of soybean rotation.