Development of mechanized cultivation techniques for a variety of soybean 'Sachiyutaka': A study on sowing time and planting density
2007
Ikejiri, A.(Yamaguchi-ken. Agricultural Experiment Station (Japan)) | Okamoto, K. | Nakatsukasa, M. | Yoshinaga, T. | Nakayama, A. | Kobayashi, Y. | Kaneko, K. | Iwamoto, T. | Murayama, H.
The study aimed to examine the effects of sowing time and planting density on the growth and yield of a new soybean variety 'Sachiyutaka' in plain (Yamaguchi city) and mountainous (Ato town) areas in Yamaguchi prefecture. This new variety was adopted as a recommended variety for Yamaguchi prefecture in 2001. It was found that appropriate sowing time for plain areas was from the middle of June to the beginning of July and in mountainous areas it was from the beginning of June to the end of June. Regarding both of the sowing times, number of shells becomes increased with smaller damages by bugs. Regardless of sowing time, 15 plants/square m or more planting density resulted in high yields in the both cultivated areas. Appearance quality of seeds depend on sowing time, however planting density had no effect on appearance quality of seeds produced in the both cultivated areas. Seed sowing from the middle of June to the beginning of July results seeds of good appearance with few beans of broken skin and very few insect infestations. The uniformity of produced seeds was good in plain areas. In mountainous areas few number of purple spotted beans were found when seeds were sown from the beginning of June to the end of June. Length of main stem gets shorter by sowing seeds after the beginning of July. When the planting density was 20 - 25 plants/square m, the stem gets longer. The shells were produced in the upper level of the plant and therefore, loss by the combine harvester was mitigated. Stem maturation was delayed by dissemination of sowing time from the middle of June to the beginning of July. Little variation of seed protein and seed oil content was found by sowing seeds from the beginning of June to the beginning of July.
اظهر المزيد [+] اقل [-]