Legumes tree hedgerows in cassava farming affecting soil productivity and cassava yield
Yoyo Soelaeman and Maswar
Integration of legume trees as hedgerows in cassava (Manihot utilisima Crantz) farming is one possibility to reduce the negative effect of cassava farming on soil productivity. The experiment was conducted in the Tamanbogo Experimental Farm in East Lampung from November 2006 to November 2008, located at 050 00’ 20” S and 1050 29’ 23” E. The field experiment had three factors of legumes hedgerow, and three factors of P fertilizer rates that were arranged in a split plot experimental design. The results showed that the total biomass of legumes tree pruning in 2007 and 2008 were not affected by P fertilization on cassava but it was affected significantly by the variety of legumes tree planted as hedgerows. The rates of P fertilization on cassava did not effect significantly on soil chemical characteristic in 2007 but it’s tend to increase in 2008. Flemingia congesta hedgerows gave a significant lower soil bulk density and highest total soil pores space in 2008. The highest yield of fresh cassava (19.98 t ha-1) was gained on Flemingia congesta hedgerows. Increasing the rates of P fertilizer from 36 to 72 kg P2O5 ha-1 increased the yield of cassava significantly in 2008.
Keywords: Manihot utilisima Crantz, Flemingia congesta, Glyricidia sepium, biomass