Abstract:
Common mesquite (Prosopis juliflora), a Fabaceae, native to South America, was first
introduced into Sudan in 1917 to curb desertification. However, the plant has spread and become
a weed of national importance and a threat to biodiversity. The present investigation was
undertaken at the College of Agricultural Studies, Sudan University of Science and Technology
to study allelopathic potentials of mesquite, and activity and persistence of the allelochemicals in
soils. In all experiments lettuce (Lactuca sativa L.) was used as a test plant. Powdered mesquite
parts including leaves, stems, barks and pods, showed differential effects on lettuce seed
germination and seedlings growth. Germination was the least affected. Seedlings growth was
affected negatively. The radicle was more sensitive to the toxins than the hypocotyl. Mesquite
pods were the most suppressive followed in descending order by bark, leaves and stems. Toxins
were active through soil and their persistence progressively declined with time. The results
suggest that mesquite parts contain water-soluble allelochemicals and that allelopathy may
contribute, considerably, to the invasive nature of the plant and its dominance.
