Journal of Research in Weed Science

Abstract In Southern Groundnut Basin of Senegal, weed management is one of the biggest challenges for improving upland rice production. This study aimed to evaluate the systematic composition and the infestation of weed species in order to promote a sustainable management in a context of biodiversity decreasing. Thus, phytosociological surveys were carried out during rainy season in upland rice fields. The results revealed that flora consisted of 62 species distributed in 47 genera and 15 families. The families with the highest species richness were Poaceae (24.2%), Fabaceae (12.9%) and Malvaceae (12.9%) which account for half of recorded species. Biological spectrum analysis showed that the flora is largely dominated by therophytes, with 95% of recorded species. Infestation diagram based on weeds abundance and frequency showed eight groups of species reflecting their degree of infestation. Among them, Digitaria horizontalis, Mariscus squarrosus, and Spermacoce stachydea belonged to major weeds and potential general weeds were potentially the most injurious against upland rice because of their high recovery and frequency.

Abstract The study was conducted with the aim of assessing the distribution and abundance of invasive alien plant species (IAPS) in two administrative Zones (1 and 3) of the Afar region. Data were collected using systematic sampling technique and regular intervals of 10 km were used during the field survey. The following weeds Calotropis procera, Cryptostegia grandiflora, Jatropha curcas, Lantana camara, Opuntia stricta, Parkinsonia aculeata, Parthenium hysterophorus, Prosopis juliflora, Senna occidentalis, and Solanum incanum were recorded in this study. Prosopis was found in 38% of the 91 sample waypoints in the altitude range of 347-1005 meters above sea level whereas C. procera was recorded in 28% of the interceptions between 347 m and 1010 meters above sea level. P. hysterophorus occurred in 15 % of the waypoints in the altitudes ranged from 603 to 1005 meters above sea level. C. grandiflora and P. aculeata were observed respectively in 3% and 6% of the interceptions while L. camara and O. stricta were recorded only at a single waypoint. Higher abundance levels were observed for P. juliflora and C. procera. The majority of the IAPS were found infesting diversified habitats such as road sides, cropland, grazing land, riversides, forest and habitation areas. Awash Fentale district had the highest IAPS richness by possessing all the recorded species. The detailed distribution maps of the identified IAPS were developed and prioritization and ranking of invasive species was made based on abundance levels. The results of this study can be used in invasive weed management or extension programs that aim to tackle major IAPS problems in the region.