2013 Volume 58 Pages 65-70
We investigated the effects of the application of sub-phosphoric acid fertilizer (granulated or dissolved in water) on the growth, yield, yield components and seed qualities of soybean (Tanbaguro), and demonstrated two fertilizer application methods for the purpose of reducing labor time. It was confirmed that root weight, plant weight of the aerial part, number of main stem nodes, number of ripening pods, weight of ripening pods, weight of seed-setting, ratio of seed-setting and ratio of 2L grade seeds were increased by the application of these fertilizers. However, application of these fertilizers did not result in improvement of the apparent quality of seeds. A duration of about 36% was required for ridge application with a backpack auxiliary tool or overall application with a battery-driven spreader on 1,000m2 compared with that for the conventional application method. Yield indexes in ridge application with a backpack auxiliary tool and overall application with a battery-driven spreader were 98 and 97, respectively, if the yield index in the conventional application method was set as 100, so yields among the three fertilizer application methods were almost the same. Consequently, it is considered that both ridge application with a backpack auxiliary tool and overall application with a battery-driven spreader are effective methods for larger-scale farmers and community farming organizations that require labor-saving approaches.
