Invasive Species Compendium

Detailed coverage of invasive species threatening livelihoods and the environment worldwide

Abstract

Biological control of natural herbivores on ambrosia species at Liaoning Province in northeast China.

Abstract

Giant ragweed (Ambrosia trifida L.) and Common ragweed (Ambrosia artemisifolia L.) are well known species native to North America and can now be found in China. These weeds are ecologically important and have the ability to spread into agricultural areas and can create future risks. This study is an attempt to investigate the control potential of the root, a pathogen and a gall forming stem insect herbivore for Ambrosia species at different locations of Liaoning Province in Northeast China. Significantly (P<0.05) high pathogen herbivore (Puccinia xanthii) abundance was investigated in sites IV and II (16.76%; 14.04%) with 58-66% humidity at site temperature ranges between minimum-maximum (20-30°C). Significant abundance (P<0.05) in stem gall insect herbivore (Epiblema strenuana) were recorded in site IV (12.49%) and site I (12.34%). This herbivore displayed a steep asymptotic curve decrease significantly from upper to lower position gave positive relationship. The value of co-efficient of determination (R2 = 0.52) as depicted gave the indication of model fitness. Pathogen herbivore displayed also a steep asymptotic curve investigated moderate positive relationship with R2 = 0.45 followed by site I (R2 = 0.36) form parabola curve. Stem galling insect and pathogen herbivores were diversified significantly with Simpson's index of diversity (SID). Similarly, root herbivore (fire ant) demonstrated its biological control potential on invasive Ambrosia artemisifolia at site I recorded significant (P<0.05) reduction in plant height (30.62%); diameter (43.21%) and number of leave (73.60%) compared to gall forming stem herbivore.