不同生长方式对2种入侵植物形态特征和生物量分配的影响

Effects of Different Growth Patterns on the Morphological Characteristics and Biomass Distribution of Two Invasive Plants

研究入侵植物南美蟛蜞菊(Wedelia trilobata)和五爪金龙(Ipomoea cairica)在匍匐和攀援方式下的形态、生物量和构件生物量分配特征,结果表明:1)匍匐的南美蟛蜞菊花数明显多于攀援的植株,差异极显著(p<0.01),而平均节间长显著(p<0.05)低于攀援植株。除平均节间长外,攀援的五爪金龙分枝节数、分枝叶片数、节总数、花数和叶总数均明显高于匍匐的植株。2)攀援的南美蟛蜞菊植株叶、节和花干重均极显著低于匍匐的植株。攀援的五爪金龙植株叶极显著高于匍匐的植株,节和花干重也高于匍匐的植株。3)匍匐的南美蟛蜞菊除花干重显著高于攀援的植株外,其余均无显著性差异。攀援的五爪金龙植株叶干重比极显著高于匍匐植株、花干重比显著高于匍匐的植株,而茎干重比则极显著低于匍匐的植株。说明南美蟛蜞菊和五爪金龙表现出在不同环境条件下具有较强的形态可塑性(尤其是五爪金龙),这也许是二者具有较强入侵性和能够成功入侵的主要原因之一。

Morphological characteristics, biomass, biomass distribution under different growing patterns of two invasive plants, Wedelia trilobata and Ipomoea cairica were investigated. The results indicated that 1） Under climbing growth, W. trilobata had more number of flowers （p〈0.01） and shorter average internode length （p〈0.05） when compared to sprawl growth. Under climbing growth, pods of branches, number of branching leaf, total number of pods, total number of leaf and number of flower of I. cairica were significantly lower （p〈0.05） than sprawl growth except for average internode length. 2） Scrambling W. trilobata had lower dry leaf weight, pods and flower compared to sprawl growth plants. On the con-trary, scrambling I. cairica had higher dry leaf weight, pods and flower. 3） Under sprawling growth, only flower weight ratio lower than scrambling W. trilobata were obtained. Leaf and flower weight ratio of scrambling I. cairica were significantly higher （p〈0. 05） than sprawl growth plants, while stem weight ratio were significantly lower （p〈0. 05）. In conclusion, both of W. trilobata and I. cairica had strong morphological plasticity and adaptation under different environments, and this may one of main factor con- tributed to strong invasiveness and successful invasion of the two species.