<i>Parthenium hysterophorus</i> L., a noxious invasive weed

Abstract

Parthenium hysterophorus L., a member of the family Asteraceae and native to subtropics of North and South America, is an invasive plant species that colonizes disturbed areas, cultivated lands, roadside vegetation, and human settlement areas. The weed has prolific seed producing ability and fast spreading in nature. The plant is rapidly infesting into tropical and subtropical regions of the world. Its occurrence in Kathmandu valley was reported first time in 1986. The seeds are highly viable and adaptive and can travel long distance with the help of its wing like structures at the base. They can anchor on rough surfaces with the help of feathered claws like structures. The weed is being very problematic because of its aggressiveness, allelopathic impacts, and health hazard risks for human and livestock. The weed posses different allelochemicals, specially sesquiterpenes and phenolics, parthenin being the chief one. The weed adversely affects crop plants and sensitive grass species. Besides it causes hay fever, dermatitis, skin infections, bronchitis and several other health impacts. The control of the weed is a challenging task; however, different herbicides and some biological agents have been reported for its management.

Key words: allelochemicals; allelopathy; health hazard; Nepal; parthenin; sesquiterpene.

DOI: 10.3126/botor.v6i0.2915

Botanica Orientalis - Journal of Plant Science (2009) 6: 85-92