Assessment of Weed Flora Composition in Parthenium (Parthenium hysterophorus L.) Infested Area of East Shewa Zone, Ethiopia

Abstract

Field survey on parthenium was conducted at East shewa Zone of Oromiya Regional State, Ethiopia during 2008 cropping season.  The objectives of the study was to assess the weed flora composition and plant species that are growing in copetation with parthenium to use those plants as potential biological management options under field condition. Assessment of weed flora composition was carried out in five Kebeles (Farmers Association) of Boset District East Shewa Zone of Oromiya Regional State, Ethiopia. Data on the species composition were recorded and samples of weed flora compositions were collected. The result showed a total of eighty five different herbaceous plant species that were collected and recorded in 63 genera and 24 families. Poaceae (21), Asteraceae (11), Fabaceae (7) and Convolvulaceae (7) were by far the richest taxa and accounted together (55 %) of the entire flora of the study area. The major plant species having higher dominance value were Parthenium hysterophorus (25.6), Cassia tora (6.07), Argemone mexicana (5.83), Xanthium strumarium (4.53), Digitaria abyssinica (3.02) and Cyperus rotundus (2.86). Similarity index values of the species composition among different kebeles ranged from 65% to 78% which indicating that weed species compositions in these locations were similar. The diversity and evenness of species declined with increasing spread of parthenium which suggests negative influence that parthenium had on the status of species diversity in the studied area. In conclusion the selected plant species that were found competitive with parthenium based on their abundance and dominance values were Argemone mexicana, Cassia tora, and Xanthium strumarium which were suggested for detailed competition experiment in order to determine their competitiveness with P. hysterophorus and will be used for biological management of it.