[P1] Field Crop Production

[P1-21] Effect of Narrow-Row Planting with Inter-Row Strip Tillage by Chisel Plough on Yield and Labor Saving to Soybean Cultivation at Field Converted from Paddy in Shonai-Plane of Japan

^○Hiroyuki Takeda¹, Hidefumi Saito¹, Naoto Ikeyama², Hiroshi Saito³ (1.Tohoku Agricultural Research Center, National Agriculture and Food Research Organization, Japan, 2.Faculty of Agriculture, Yamagata University, Japan, 3.Rice Breeding and Crop Science Experiment Station, Yamagata Integrated Agricultural Research Center, Japan)

It has become difficult to manage soybean cultivation because of insufficient labor against to increasing cropping area although soybean cultivation converted from paddy has been increased in Shonai-plain at the side of Japan Sea of Tohoku region in Japan. To reduce labor on conventional cultivation (CC) and to increase yield we introduced a sowing machine developed in NARO which could not only be planted in narrow row without preliminary tillage and ridge making but also be kept soil moisture suitable by the inter-row strip tillage with chisel plough. For the experiment, soybean cv. Satonohohoemi was cultivated on farm-owned field located at Shonai-plane in 2016 - 2018. There was no significant difference in average soybean yield among three years between narrow-row cultivation (NRC) and CC. The maximum yield was got at the case of cultivation including at field just converted after paddy, which in NRC were 273 g/m2 by hand harvesting or 227 kg/10 a by combine harvester. Total working time in NRC was 7.4 hours per 10 a which was equivalent to about 20 percent decrease against CC. Total cost per 10 a on NRC was 64.3 thousand-yen witch equivalent to 4 percent decrease to CC in spite of the induction of new sowing machine. Among 3-year experimentation, NRC with inter-row strip tillage by chisel plough of soybean has no superiority on the yield than in CC, however it was contributed to the reduction of total working time in CC.