紫斑牡丹种子浸提液对植物种子萌发和幼苗生长的影响

以紫斑牡丹种子为研究对象,研究不同质量浓度(0、0.025、0.050、0.075、0.100 g·mL-1)的种皮和胚乳水浸提液对白菜、小麦和绿豆种子萌发、幼苗生长和幼苗的抗氧化酶活性的影响,探究紫斑牡丹种子内源抑制物质的活性,为进一步研究紫斑牡丹种子休眠机理提供理论依据。结果表明:紫斑牡丹种皮和胚乳中均含有抑制受体植物种子萌发和幼苗生长的物质,且同一质量浓度下,胚乳浸提液的抑制作用强于种皮浸提液;种皮和胚乳浸提液对白菜幼苗生长的抑制作用高于小麦和绿豆;种皮和胚乳浸提液对3种受体植物幼苗根长的抑制作用大于苗高和鲜质量;种皮和胚乳浸提液对3种受体植物幼苗的SOD、CAT和POD活性均产生了一定的影响。其中,随着种皮浸提液质量浓度的提高,受体植物幼苗SOD、POD活性先上升后下降,而CAT活性持续下降;加入胚乳浸提液后,受体植物幼苗的CAT、POD活性与对照相比显著下降,SOD活性则依然随着胚乳浸提液质量浓度的升高而表现出先上升后下降的趋势。由结果可知,紫斑牡丹种皮和胚乳浸提液中均含有能抑制受体植物种子萌发和幼苗生长的物质,并且能够影响受体幼苗的抗氧化酶活性,但是紫斑牡丹种皮和胚乳内源抑制物质的活性存在一定的差异。

Effects of Crude Extracts of Paeonia rockii Seeds on Germination and Seedling Growth of Receptor Plant

The effects of aqueous extracts of seed coat and endosperm with different concentration(0,0.025,0.050,0.075 and 0.100 g·mL-1)of Paeonia rockii on the seed germination,seedling growth and antioxidant enzymes of Brassica campestris,Triticum aestivum and Vigna radiate were examined to study the reason of seed dormancy and characteristics of endogenous inhibitory substance of P.rockii,and the seed dormancy mechanism of Paeonia rockii.There were endogenous inhibitory substances both in seed coat and endosperm,and the inhibitory action of endosperm was stronger than that of seed coat in the same concentration.The inhibitory action of aqueous extracts of seed coat and endosperm on seedling growth of B.campestris was strongest in three receptor plant.Inhibition by P.rockii aqueous extracts of seed coat and endosperm,the strength on seedling growth of three receptor plant inhibited principally root length.The inhibitory substances in the seed coat and endosperm caused the changes of antioxidant enzyme activity.With the increase of the seed coat aqueous extract concentration,the activities of superoxide dismutase(SOD)and peroxidase(POD)increased first and then decreased,while catalase(CAT)activity continued to decline.After treated with aqueous extract form endosperm,the activities of CAT and POD were significantly decreased compared with control group,and SOD activity still increased first and then decreased with the increased concentration of the endosperm extract.The study found that there are chemical substances both in seed coat and endosperm of P.rockii,which could inhibit the seed germination and seedling growth of receptor plants,and affect the activity of antioxidant enzymes in seedlings.However,there were differences in the activity of the inhibitors contained in seed coat and endosperm of P.rockii.