Growth Performance of the Seedlings of Four Acacia Species Raised in Compost-Amended Sandy and Silty Soils

Abstract

The objective of this study was to determine the effects of
compost on growth of Acacia nilotica, A. seyal, A. senegal and A. tortilis
seedlings. It was conducted in Khartoum University Farm, during
December 1999- January 2002. Compost was prepared in a pit from forest
litter and poultry manure. Four quantities of compost were added to a
sandy soil and a silty soil (% volume): zero, 25%, 50% and 75%. The
blends were packed in polythene bags prior to transplanting. The compost
was slightly acidic, non-saline, and rich in nutrients and had high water
holding capacity. The compost negatively affected acacia seed
germination percentage by 1.5 to 5.3 folds compared to the mineral soils.
Shoot height in the compost-sand mixes increased significantly as
compared to the unamended sandy soil by 1.4 to 2 folds. Root length was
generally lower in the compost treatments. Shoot and root biomass in the
compost media was significantly higher than in the sandy soil and
increased by 3 to 7 and 1.5 to 3.0 folds, respectively. In the silt-compost
mixes, seedlings' shoot heights were significantly greater than in the
unamended silty soil. Root lengths in the silt-compost mixes were not
significantly different from those in the silty soil. Shoot and root biomass
in the silt-compost mixes was not significantly different from that in the
unamended silty soil. Compost effects on seedlings’ growth occurred in