紫茎泽兰凋落物提取液对自身种子萌发和幼苗生长的影响

Effects of Eupatorium adenophorumii Litter Aqueous Extract on Its Seed Germination and Seedling Growth

采用恒温培养法研究了不同浓度紫茎泽兰凋落物提取液对其种子萌发和幼苗生长的影响。结果表明:紫茎泽兰凋落物提取液对自身种子萌发与幼苗生长起到一定程度的抑制作用,并且浓度越高抑制作用越强;当提取液浓度低于0.05g/ml时,种子萌发和幼苗生长过程中各指标与对照均无显著差异(p>0.05);提取液浓度高于0.05g/ml时,种子发芽率、发芽势、发芽指数、胚根长、幼苗鲜重和干重随提取液浓度的增加急剧降低(p<0.05),并且紫茎泽兰凋落物提取液延长了种子发芽时间,而对幼苗鲜重和干重影响不显著(p>0.05);高浓度(0.30g/ml)紫茎泽兰凋落物提取液致使种子失活。统计相关检验表明,紫茎泽兰叶片丙二醛(MDA)含量、细胞膜透性均与提取液浓度呈显著的线性正相关(p<0.001),叶绿素含量、根系活力(TTC)、保护性酶(POD,SOD,CAT)和非保护性酶(PPO,PAL)活性均与提取液浓度呈显著的线性负相关(p<0.001)。综合以上结果表明紫茎泽兰凋落物提取液对其种子萌发和幼苗生长存在一定程度的自毒作用。

Seed germination and seedling growth of Eupatorium adenophorumii were measured under treatments of its litter aqueous extracts with the concentrations ranging from 0.05 to 0.30gDW/ml under incubation.The results showed that the indexes of seed germination and seedling growth were significantly inhibited by the higher concentration of Eupatorium adenophorumii litter aqueous extract.When the concentration of aqueous extract was 0.05g/ml,the indexes of seed germination and seedling growth was no significant difference with CK（p0.05）.Seed germination rate,germination potential,germination index,radicle length,seedling fresh weight and dry weight were sharply reduced with the increase of the aqueous extract concentration（p0.05）.At the same time,the seed germination time was delayed when the concentration of aqueous extract was higher than 0.05g/ml,but the increase of seedling dry weight were not affected under the same concentration.The higher Eupatorium adenophorumii litter aqueous extract（0.30g/ml）led to the seed deactivation.Correlation analysis showed that contents of malondialdehyde（MDA）and membrane permeability were a significant linear positive correlation with aqueous extract concentration（p0.001）,respectively.The content of chlorophyll,root activity（TTC）,protective enzyme（POD,SOD,CAT）and the activity of protective enzyme（PPO,PAL）had the significant linear negative correlation with aqueous extract concentration（p0.001）.Comprehensive analysis indicated that the aqueous extracts from the litter of Eu-patorium adenophorumii had autotoxicity on its seed germination and seedling growth.