수도(水稻)의 기계이앙시기(機械移秧時期)와 묘령(苗令)이 출수(出穗) 및 수량(收量)에 미치는 영향(影響)

Effect of the Transplanting Date and Seeding Age on the Flowering and Grain Yield of Rice under Mechanical Transplanting

수도(水稻)의 기계이앙재배시(機械移秧栽培時)에 알맞는 이앙시기(移秧時期)와 육묘일수(育苗日數)를 밝히고저 시험(試驗)한바 통일계(系)인 밀양(密陽)23호(號)는 만식(晩植)에 의(依)하여 출수(出穗)가 크게 늦어지고 등숙(登熟)이 불량(不良)해지므로 출수(出穗)의 적기(適期)는 8월초순(月初旬)이고 이앙(移秧)의 적기(適期)와 만한(晩限)은 각각(各各) 5월하순(月下旬)과 6월상순(月上旬)으로 추정(推定)되고 기계이앙시(機械移秧時)에는 인력이앙시(人力移秧時)보다 4월이상(日以上) 이앙(移秧)을 앞당길 필요(必要)가 있으며 중묘(中苗)가 유리(有利)하였다. 한편 일반형(一般型)인 밀양(密陽)15호(號)는 만식적응성(晩植適應性)이 있어 늦심기하여도 출수(出穗)의 지연도(遲延度)가 적으며 등숙률(登熟率)도 비교적(比較的) 높고 수량(收量)도 많아 그 출수적기(出穗適期)는 8월중순(月中旬)이며 따라서 이앙(移秧)의 적기(適期)는 6월초순(月初旬), 만한(晩限)은 6월하순경(月下旬頃)이고 이앙적령(移秧適令)은 20~30일묘(日苗)로 추정(推定)되었다.

The study was done to determine the proper transplanting dates and seedling ages of rice when mechanical transplanting was attempted. Heading dates of the Milyang #23, developed from Tong-il rice was delayed by delayed transplanting and the percent of filling grain was also low. The proper heading dates for the variety should be the first part of August and the transplanting should be done by the end of May. The presumed last days for the transplantation was considered early part of June. 30 to 40 days old seedlings were very effective to have healthy rooting systems. However, the Milyang #15 had shown more tolerance to the late transplantation than Milyang #23 and the degree of delaying heading dates due to the delayed transplantation was rather smaller than that of the Milyang #23. Even when the Milyang #15 was transplanted on June 30, the heading dates were around the middle of August and the ripening percentage was comparatively high and yield was also high. Therefore, the proper heading dates of the Milyang #15 might be around the middle of August and transplanting dates should be the first part of June. The possible last dates of transplantation of the Milyang #15 was assumed to be the last days of June and the proper seedling ages would be 20 to 30 day after sowing.