Testing of a battery-operated spreader for rice fertilizer application hotos, tables, and graphics 014 Rashad Hegazy, Carlito Balingbing, Joseph Sandro, Helmut Lehner, and Martin Gummert International Rice Research Institute, DAPO Box 7777, Metro Manila 1301, Philippines Email address: c.balingbing@irri.org Fertilizer application in most Asian farms is still done manually, leading to a high cost of labor and an uneven fertilizer distribution pattern. Modern methods are being tried, such as overhead sprinklers for crop fertilization and irrigation (fertigation). Options for small machines are also available, such as the battery-driven mechanical spreader, which is readily available in the market. This poster shows ther results of an initial testing done to evaluate a 12-volt Polaro spreader machine for rice fertilizer application. Compound fertilizer can be effectively spread at 4 to 6.6 m with 11% difference on both sides at 270 rpm disc speed. Increasing the disc speed to 600 rpm gives a maximum spreading width of 9.6 cm. The fine crystal Muriate of Potash (MOP) was not uniformly distributed by the spreader under any setting. In the field, the spreader showed uniform distribution of complete fertilizer at a rate of 218 kg/ha at first application. The differences in both spreading sides for fertilizer rates of 50%, 75%, and 100% were 13.62%, 12.56%, and 40.85%, respectively. With manual spreading, the distribution was not uniform with a higher difference of 146.51% on one side, as compared to the other side (Fig. 3). Materials and methods The machine is a 12V Polaro spreader for salt and fertilizer from Lehner GmbH (Fig. 1). It was powered by a 12V battery from an old Korean transplanter (Fig. 2) with a maximum speed of 3.5 km/h at third gear, and a first-gear speed of 1.44 km/h. Fig. 1. Component parts of Polaro spreader (A) frame, slider, spreading discs; and hopper (B) display panel. A B Stationary testing was done on a paved floor to evaluate the spreading pattern. Fertilizer distribution was tested at different speeds on the disc spreader. Three types of fertilizer were used: Urea (46-0-0), complete fertilizer (14-14-14), and Muriate of Potash (0-0-60). Field testing was conducted on a 7,160-m2 rice field subdivided into 12 sub-plots, with one level of randomized split-split plot replications to compare manual and mechanical spreading. Three fertilizer rates were used: 100%, 75%, and 50% of the recommended rate, which is 182 kg Urea + 32 kg of P2O5 + 32 kg of K2O per ha. Swath width of the spreader was set at 5.5 and undercarriage speed was on first gear. Preliminary results At stationary testing, the spreader showed good results in distributing Urea at an effective width of 4.5 to 6 m and a disc speed of 270 to 390 rpm. At 650 rpm disc speed, distribution pattern has a 6.6% difference on both sides. A maximum spreading width of 8.4 m is achievable at 600 rpm. Fig. 3. (Left) Spreading patterns of Polaro machine in rice field; (Right) aerial photo of experimental plots at booting stage. Conclusions The battery-powered fertilizer spreader can be used effectively on both Urea (46-0-0) and complete fertilizer (14-14-14) at a spreading width of 5.5 m and undercarriage speed of 1.44 km/h. The distribution uniformity is better with a mechanical spreader than manually broadcasting fertilizer. With the current settings, the mechanical spreader cannot achieve uniform distribution for MOP. Further trials will focus on improving the distribution of MOP and similar granulates by modifying the settings of the casting shovels on the spreader discs. B A Fig. 2. (A) The old Korean transplanter with the spreader attached; (B) the spreader being maneuvered in the field. Acknowledgments Thanks go to Lehner GmbH for donating the spreader in this experiment. We also appreciate the IRRI Experiment Station for logistical support in conducting the field experiments.