No abstract

The biomass of a six-year-old plantation of Prosopis juliflora was determined using simple linear regressions of (y) the tree components: stem (over bark), large branches, small branches and leaves on (x), diameter at the base of the trees. Similar regressions were used to estimate height and volume produced by both stem and large branches. Macronutrient concentrations in the different tree components were determined and multiplied by the appropriate total dry weights to obtain total contents per hectare. The total stem volume (at age 6) was 209 m3/ha and large branch volume was 75 m3/ha. Total biomass was 216 tons/ha. Over 77% of the total biomass was accounted for by stem and large branches. Nevertheless, the leaves plus small branches (making 22.6% of the biomass) contained over 50% of the total pool of the individual nutrients N, P, K and Mg. The implications of this finding on site depletion due to total tree use as fuelwood and fodder is discussed.

No abstract

No abstract

Naphthylisoquinoline alkaloid-containing extracts [1-20] of four species of the genus Ancistrocladus (A. barteri, A. heyneanus, A. robertsoniorum, and A. tectorius) and of Triphyophyllum peltatum have been examined for their antiplasmodial activity against asexual erythrocytic forms of Plasmodium falciparum (NF 54, clone A1A9) and P. berghei (Anka) in vitro. Incorporation of 3 H-hypoxanthine was measured in the presence of the test substances. The above mentioned plant species are used in several countries of the pantropical area against fevers and malaria. Five of the examined extracts displayed high growth inhibiting activity in the P. falciparum system: CH 2 Cl 2 /NH 3 bark extract of T. peltatum [20], EtOH leaf extract of A. barteri [4], CH 2 Cl 2 leaf [14] and CH 2 Cl 2 /NH 3 bark [15] extracts of A. tectorius, and CH 2 Cl 2 leaf [17] extract of T. peltatum). These extracts (IC 50 < 1 µg/ml) [4, 14, 15, 17, and 20] were further examined in the P. berghei system. Two of them (the CH 2 Cl 2 /NH 3 bark extracts of A. tectorius [15] and T. peltatum [20]) were proven to be highly active in both test systems. These findings confirm that extracts of species belonging to the Ancistrocladaceae and the Dioncophyllaceae have a considerable antiplasmodial capacity.