Determination of sugarcane yield advantages of Mycorrhiza inoculants on Ferralsols

Sugar cane (Saccharum officinarum L.) is the source of sugar in all tropical and subtropical countries of the world. Understanding the performance of sugarcane in Uganda is therefore vital in light of the new challenges for the development of agriculture and the growing economic demand for sugar in the tropics. Soil micro organisms’ interactions are among the major sugarcane yield determinants, though little is known about it in Uganda. This study thus, determined sugarcane yield advantage of AMF inoculation under ferralsols. A bioassay experiment was set up at Lugazi Sugar Corporation of Uganda Limited with sorghum to trap mycorrhiza spores, which were identified at the botany laboratory of Makerere University. The AMF spores were extracted from 50 cm3 soil samples by wet sieving and sucrose gradient centrifugation. The number of spores in 1000g of mycorrhized soil was determined. Four treatments (Mycorrhiza alone-T1, mycorrhiza and rock phosphate-T2, rock phosphate-T3and the control-T4) were considered and replicated 4 times randomly. Mycorrhized soil and with rock phosphate was applied in the planting lines. The plots had 10 rows consisting of six lines separated by 1.35 m within the plot and 3 m from one plot to the next. There were six rows per plot. Weeding was carried out regularly and readings were taken every week after one month of germination. The study found six AMF genera in Lugazi dominated by Acaulospora and Glomus. The phosphorus levels were also very low. Rock phosphate and mycorrhiza combination enhanced significantly sugarcane yield. Results of the study indicate a good scope for AMF inoculum selection and commercially utilising the efficient AMF strains for improved agricultural productivity.