파종기이동(播種期移動)이 Indica친수도품종(親水稻品種)/계통(系統)의 출수기(出穗期)의 생태적(生態的) 변이(變異)에 미치는 영향(影響)

조재성,Jo, Jai Seong 충남대학교 농업과학연구소 1975 Korean Journal of Agricultural Science Vol.2 No.2

최근 새로 육성(育成)된 Indica친수도품종(親水稻品種)/계통(系統)의 파종기이동(播種期移動)에 따르는 출종기(出種期)의 생태적변이(生態的變異)를 구명(求明)하기 위하여 21개(個) Indica친수도품종(親水稻品種)/계통(系統)과 대비품종(對比品種)으로 13개(個) Japonica 품종(品種)을 4월(月) 1일(日)부터 10일(日) 간격(間隔)으로 6회파종(回播種)하고 한편으로 단일처리구(短日處理區)와 고온처리구(高溫處理區)를 설치(設置)하여 각품종(各品種)/계통(系統)의 출종기(出種期)를 조사분석(調査分析)하였던 바 그 결과(結果)를 요약(要約)하면 다음과 같다. 1) Japonica 품종(品種)은 물론 Indica친품종(親品種)에서도 파종기(播種期)가 늦어짐에 따라 출수(出穗)까지의 일수(日數)는 거의 직선적(直線的)인 단축(短縮)을 보였다. 2) Japonica 수도품종군(水稻品種群)에서는 조생종(早生種)은 고온(高溫)에 의한 출수기(出穗期)의 단축효과(短縮效果)가 컷으나 중만생종에서는 약간의 단축효과(短縮效果)를 보였거나 혹은 약간 늦어 졌는데 Indica친수도품종(親水稻品種)/계통상(系統詳)에서는 대체로 품종(品種)의 조만생에 관계(關係)없이 고온조건하(高溫條件下)에서는 출수기(出穗期)가 오히려 현저히 늦어졌다. 3) Japonica 수도품종군(水稻品種群)에서는 출수기(出穗期)의 단축(短縮)에 미치는 단일(短日)의 효과(效果)가 중만생종에서 크고 조생종(早生種)에서 작았으나 Indica친수도품종(親水稻品種)/계통군(系統群)에서는 단일효과(短日效果)가 품종(品種)의 조만성과는 전혀 무관(無關)하게 나타났다. 4) 고온조건하(高溫條件下)에서의 출수(出穗)까지 일수(日數)는 Japonica품종군(品種群)이나 Indica 친품종군(親品種群)에서 모두 일반재배시(一般栽培時)의 출수(出穗)까지 일수(日數)보다 길었는데 단일조건하(短日條件下)에서는 Japonica 계수도품종군(系水稻品種群)의 출수(出穗)까지 일수(日數)는 일반재배시(一般栽培時)의 출수(出穗)까지 일수(日數)보다 짧았으나 Indica친수도품종군(親水稻品種群)에서는 일반재배시(一般栽培時)의 출수(出穗)까지 일수(日數)보다 길었다. 5) Japonica계(系)나 Indica친수도품종군(親水稻品種群)에서 모두 각파종기(各播種期)에서의 품종(品種)의 조만성과 일반대배시(一般對培時)의 품종(品種)의 조만성간에는 고도(高度)의 유의상관(有意相關)이 인정(認定)되었다. 6) Japonica 계수도품종군(系水稻品種群)에서는 파종기(播種期)지연에 따르는 출수(出穗)까지 일수(日數)의 단축율(短縮率)과 품종(品種)의 조만성간에 비교적(比較的) 높은 상관(相關)($P{\fallingdotseq}0.1$)이 인정(認定)되었으나 Indica친품종군(親品種群)에서는 이 양자문(兩者問)에 전혀 상관관계(相關關係)가 인정(認定)되지 않았다. This experiment was carried out to obtain some imformations about the ecological variations of the heading time of the newly breeded Indica x Japonica varieties/pedigrees according to the seasonal changes of the seeding date. day length and temperature. The results obtained are summarized as follows; 1) At all varieties. days to heading showed a straight reduction according as the seeding time was delayed. 2) At the group of Japonica varieties. the days to heading of early maturing varieties were much shortened and that of medium or late maturing varieties were little or not shortened under high temperature condition but at the group of Indica ${\times}$ Japonica va rieties/pedigrees. days to heading were significantly elongated under high temerature condition. 3) At the group of Japonica varieties. the effect of the short day condition on the days to heading was significantly high at the medium and the late maturing varieties than at the early maturing varieties. however. the short day effect on the reduction of days to heading was not related with the earlyness of each varieties at the group of Indica ${\times}$ Japonica varieties/pedigrees. 4) Days to heading of all varieties under the high temperature condition were longer than that under the ordinary culture. On the other hand, the days to heading of Japonica varieties under the short day treatment were shorter than the days to heading of ordinary culture but at the group of Indica x Japonica varieties/pedigrees. the days to heading under the short day treatment were longer than ordinary culture. 5) At both varieties groups. the days to heading at each seeding time were significantly correlated with days to heading at ordinary cultivation. fl) At the group of Japonica varieties. relatively high correlation(p=0.1) was recognized between the days to heading by delay of seeding time, but at the group of Indica ${\times}$ Japonicava rieties/pedigrees, correlation between the ordinary heading date and the shortening rate of days to heading was very low.

기상요인(氣象要因)이 수도(水稻)의 생육(生育) 및 수량(收量)에 미치는 영향(影響)

조재성,이종철,Jo, Jai Seong,Lee, Jong Cheol 충남대학교 농업과학연구소 1975 Korean Journal of Agricultural Science Vol.2 No.1

기상요인(氣象要因)과 수도(水稻)의 생육(生育) 및 수량(收量)과의 관계(關係)를 구명(究明)하고자 13개(個) 수도품종(水稻品種)에 대(對)하여 6년간(年間)의 수도(水稻)의 생육(生育) 및 수량(收量)을 조사분석(調査分析)하여 보았던바 그 결과(結果)를 요약(要約)하면 다음과 같다. 1. 평균기온(平均氣溫)의 년차변이(年差變異)는 7월(月) 상중순(上中旬) 및 8월(月) 하순(下旬), 9월상순(月上旬)에서 컸고 6월하순(月下旬)과 7월하순(月下旬)에서 가장 적였다. 일조시수(日照時數)의 년차변이(年差變異)는 1월중구(月中句)에서 가장 컸으며 6월하구(月下句)및 7월하구(月下句)에서 가장 적었다. 2. 수량구성요소중(收量構成要素中) 수수(穗數)의 년차변이(年差變異)가 가장 컸고 현미천립중(玄米千粒重)의 년차변이(年差變異)가 가장 적었으며 품종별(品種別) 각형질(各形質)에서의 년차변이(年差變異)의 정도(程度)는 각각(各各) 다른 경향(傾向)이었다. 3. 수량(收量)에 미치는 직접효과(直接效果)는 등숙비율(登熟比率)이 가장 컸고 다음이 현미천립중(玄米千粒重)이었으며 수량(收量)에 대(對)한 수량구성요소(收量構成要素)의 영향(影響)은 해에따라 상당(相當)히 다른 경향(傾向)을 보였다. 4. 평균기온(平均氣溫)이 높을수록, 그리고 일조시수(日照時數)가 길수록 최고분얼기(最高分蘖期)는 지연(遲延)되었으며 한편출수기(出穗期) 까지의 일수(日數)는 단축(短縮)되었다. 5. 이앙후(移秧後) 11~40일(日)의 평균기온(平均氣溫)과 입수간(粒數間)에는 높은 (-)의 상관(相關)이 인정(認定)되었고 이앙후(移秧後) 61~70일(日)의 평균기온(平均氣溫)과 입수간(粒數間)에는 (+)의 상관(相關)이 인정(認定)되었다. 출수전(出穗前)의 고온(高溫)은 등숙비율(登熟比率)을 증가(增加)시키는 경향(傾向)이 였으나 출수직후(出穗直後)의 고온(高溫)은 등숙비율(登熟比率)을 오히려 감소(減少)시키는 경향(傾向)이 였다. 6. 적산기온(積算氣溫)과 천립중(千粒重) 간(間)에는 전기간(全期間)에서 높은 (+)의 상관(相關)을 보였다. 이앙후(移秧後) 61~70일(日)의 평균기온(平均氣溫)과 현미중(玄米重) 간(間)에 가장 높은 (+) 상관(相關)을 보였고 출수후(出穗後)의 평균기온(平均氣溫)과는 (-)의 상관(相關)을 보였다. 7. 호등숙비율(登熟比率)과 적산일조시수(積算日照時數) 간(間)에는 높은 유의상관(有意相關)을 보였으며 이앙후(移秧後) 31~50일(日) 및 61~70일(日)의 일조시수(日照時數)와 등숙비(登熟比) 율간(率間)에 높은(+)의 상관(相關)을 보였다. 현미수량(玄米收量)과 일조시수간(日照時數間)에는 이앙후(移秧後) 51~60일(日)에서 높은 (+)의 상관(相關)을 보였다. 6 years data on the plant growth and grain yield of 13 rice varieties were investigated to define the relations between meteological conditions and plant growth of rice including grain yield. The results obtained are summarized as follows; 1. Variation of average temperature by years showed great number at early and middle July, middle August and early November, however smallest figure at late June and late July. And that of sunshine hours by years were least at late June and late July, and largest at middle July. 2. Among rice yield components variation of panicle number per hill by years was biggest and that of 1000 grain weight least. Rate of variation of plant growth and rice yield was different by rice varieties. 3. Direct effects on rice yield was greatest at maturing ratio and next at 1000 grain weight. The effects of yield factor on the rice yield wers different by years. 4. Higher temperature and longer sunshine delayed the miaxmum tillering stage but shortened the days from seeding to heading. 5. A significant negative correlation was recognized between the number of panicles per hill and average temperature of 11 to 40 days after transplanting, and number of grains per panicle was correlated with the average temperature of 11 to 70 days after transplanting. High temperature before heading time showed atime decreased maturing ratio. 6. Accumulated temperature was highly correlated with 1000 grain weight in all season. Highest positive correltaion was recognized between grain yield of rice and average temperature of 61 to 70 days after transplanting but correlations between rice yield and average temperature after heading stage were negative. 7. Highly significant correlations were confirmed between maturing ratio and sunshine hours of 31 to 50 days as well as 61 to 70 days after transplanting, and maturing ratio was highly correlated with accumulated hours of sunshine. Correlation between rice yield and hours of sunshine was significant at 51 to 60 days after transplanting.

이모작답(二毛作畓)에 있어서 수도이앙기(水稻移秧機)의 실용화(實用化)에 관(關)한 연구(硏究)

김성래,김영래,조재성,이상우,Kim, Soung-Rai,Kim, Young-Rae,Jo, Jai-Seong,Lee, Sang-Woo 충남대학교 농업과학연구소 1977 Korean Journal of Agricultural Science Vol.4 No.1

수도재배(水滔栽培)에 기계이앙(機械移秧)을 실시(實施)하기 위(爲)하여 조생통일외(早生統一外) 3개(固) 품종(品種)을 4월(月) 16일(日)부터 10일(日) 간격(間隔)으로 3회(回) 상자육묘(箱子育苗)하고 40일묘(日苗)를 이앙기(移秧機)로 이양(移秧)하였던 바 묘(苗)의 생육(生育)과 기계이앙후본답(機械移秧後本畓)에서의 수도(水滔)의 생육(生育)과 수량(收量)을 조사(調査)한 결과(結果)를 요약(要約)하면 다음과 같다. 1. 40일묘(日苗)의 초장(草長)과 엽수(葉數)는 관행육묘(慣行育苗)에 비(比)해 상자육묘구(箱子育苗區)에서 현저(顯著)히 짧은 경향(傾向)이었으며 상자육묘(箱子育苗)의 경우 물못자리 상자육묘구(箱子育苗區)의 초장(草長) 및 엽수(葉數)가 밭못자리구(區)보다 현저(顯著)히 길었다. 2. 40일묘(日苗)를 단근(斷根)하여 발근력(發根力)을 시험(試驗)한 결과(結果) 상자육묘구(箱子育苗區)의 발근력(發根力)은 관행육묘구(관行育苗區)의 발근력(發根力)에 비(比)해 현저(顯著)히 낮았다. 한편 같은 상자육묘구(箱子育苗區)에서는 물못자리 상자육묘구(箱子育苗區)의 묘(苗)의 발근력(發根力)이 밭못자리에 비(比)해 높은 경향(傾向)이었다. 3. 본시험(本試驗)에 공시(供試)된 유일계(流一系) 품종(品種)은 상자육묘(箱子育苗)의 경우 못자리에서 25~30일(日) 경(頃) 부터 잎의 상부가 황변(黃變) 내지 황적색(黃赤色)으로 변(變)하고 생육(生育)이 거의 정지(停止)되는 현상(現像)을 나타내었다. 4. 상자육묘(箱子育苗)의 기계이앙구(機械移秧區)는 관행육묘이앙구(慣行育苗移秧區)에 비(比)해 활착(活着)이 5~7일(日) 이상(以上) 지연되었으며 출수기(出穗期)도 품종(品種)에 따라 차이(差異)가 있으나 대체로 5~7일(日) 지연되었다. 5. 정조수량(正粗收量)은 유신(維新)의 관행재배구(慣行栽培區)에 비(比)해 모두 약간의 감수(減收)를 보였는데 기계이앙구내(機械移秧區內)에서는 5월(月) 26일(日) 이앙(移秧)의 경우 통일(統一)의 수량(收量)이 가장 높았고 6월(月) 15일(日)의 수량(收量)은 밀양(密陽) 15호(號)가 가장 많았으며 기계이앙재배(機械移秧栽培)를 위(爲)한 품종(品種)의 선택(選擇)은 중요(重要)한 것으로 인정(認定)된다. 6. 수도이앙기(水滔移秧機)로는 $3.3m^2$당(當) 이앙주수(移秧株數)를 73주(株)부터 108주(株)까지 조정(調整)이 가능(可能)하며 파종밀도(播種密度)가 균일(均一)하면 결주율(缺株率) 1% 미만(未滿)의 작업정도(作業精度)로 인력이앙작업(人力移秧作業)에 비(比)하여 2조(條)의 경우 5~6배(倍)의 이앙작업능률(移秧作業能率)을 올릴 수 있으므로 단작지대(單作地帶)에서는 실용화(實用化)가 용역(容易)하리라 믿는다. 7. 이모작지대(二毛作地帶)에서는 이앙시기(移秧時期)가 한정(限定)되어 있으므로 적절(適切)한 품종(品種)의 선택(選擇)과 상자묘(箱子苗)의 육묘기술(育苗技術)이 개발(開發)된다면 수량(收量)은 감소(減少)없이 이앙작업(移秧作業)의 기계화(機械化)가 무난(無難) 할 것으로 전망(展望)된다. In order to investigate the effects of mechanical transplanting on the rice, four rice varieties including Jo-saing Tongil were planted in case nursering bed for three times with 10 days interval beginning from April 16. Fourty days old seedlings were transplanted with rice-transplanter, and growth habits of seedlings in bed and rice plants in main field and yield were examined and summerized as follows: 1. The plant height and number of leaves of the 40 days old seedling in case nursery bed were appeared to be less than those of seedlings grown in ordinary nursery bed. In case nursery, the plant height and number of leaves of seedlings grown in case nursery were apparently higher than those of seedlings grown in upland case nursery. 2. The root of 40 days old seedlings were cut to investigate the rooting ability of seedlings, and the rooting ability of the seedlings grown in the case nursery bed were apparently lower in the rooting ability compared with the seedlings grown in ordinary nursery bed. The rooting ability of the seedlings grown in the lowland case nursery was higher than that of the seedlings grown in the upland case nursery. 3. The tip of leaves of the varieties derived from Indica type were becoming yellow and yellow-red in color 25 to 30 days after planted in the case nursery bed. Those varieties was almost stopped growth. 4. The seedlings transplanted by transplanter had shown more than five to seven days of delay in rooting, compared with the seedlings transplanted by ordinary method. The heading dates was delayed five to seven days when transplanter was used, even though the delay of heading dates was a little different depending on the varieties. 5. The yields of unhulled rice were a little lower than that of Yusin variety which was hand planted. When mechanically transplanted, the yield of Tongil variety was highest in the plot where seedlings were transplanted on May 26. When transplanted on June 15, Milyang#15 was highest in yield, indicating the importance of varietal selection in mechanical transplantation. 6. The rice transplanter could transplant from 73 to 108 seedlings per $3.3m^2$. If the seeds of rice were evenly planted in the bed, the two-row rice transplanter could be used five to six times more effectively with less than one percent of missing plant compared with the hand transplanting. This suggests that rice transplanter could be utilized in the mono cropping area. 7. Since the time of transplantings in the double-cropping area is rather limitted, mechanical transplantation might be possible without reducings yield providing better adapted varieties and improved case-nursery techniques.

율무재배(栽培)에 관(關)한 연구(硏究)

최창열,조재성,Choi, Chang-Yoel,Jo, Jai-Seong 충남대학교 농업과학연구소 1976 Korean Journal of Agricultural Science Vol.3 No.1

율무재배(栽培)에 있어서 알맞는 재식거리(栽植距離)를 구명(究明)하고 시비량(施肥量) 특(特)히 질소질비료(窒素質肥料)의 적정시용량(適正施用量)과 주당재식본수(株當栽植本數)등을 밝히고자 재래종(在來種) 율무를 1975년(年) 5월(月) 15일(日)에 파종(播種)하여 본시험(本試驗)을 실시(實施)하였던바 다음과 같은 결과(結果)를 얻었다. 1. 재식거리(栽植距離)의 차이(差異)는 율무의 출수기(出穗期) 및 성숙기(成熟期)에 크게 영향(影響)을 미치지 않았다. 2. 재식거리(栽植距離)에 있어서 는 $90cm{\times}(30cm+30cm)$의 2조병목식구(條竝木植區)의 수량(收量)이 가장 많았으며 $40cm{\times}20cm$의 밀식구(密植區)에서의 수량(收量)은 가장 적었다. 3. 질소시용량(窒素施用量)에 있어서는 10a당(當) 시용량(施用量)이 20kg까지 증가(增加)됨에 따라서 간장(稈長) 및 간중(稈重)이 현저(顯著)하게 증가(增加)하였다. 4. 10a당(當) 20kg 질소시용구(窒素施用區)의 10a당(當) 수량(收量)은 613kg로서 가장 많았으나 10a당(當) 15kg 질소시용구(窒素施用區)의 수량(收量) 603kg와는 통계적(統計的)으로 유의차(有意差)가 인정(認定)되지 않았다. 5. 주당(株當) 재식본수(栽植本數)에 있어서는 1본식구(本植區)의 수량(收量)이 가장 많았으며 주당(株當) 3본식구(本植區)의 수량(收量)은 주당(株當) 1본식구(本植區)에 비(比)하여 28.4%의 감수(減收)를 초래(招來)하였다. These studies were carried out to find out the most reasonable planting density and :adequate amount of nitrogen fertilizer for the pearl barley. and results obtained are summarized as follows; 1. The planting densities affected neither the heading date nor the maturing date of p. earl barley. 2. The planting density of 90cm X (30cm+30cm) was the most adequate for high yield and that of $40cm{\times}20cm$ which was the most densely planted plot in this experiment showed the lowest grain yield. 3. The height and weight of stem were significantly increased by increased fertilization of nitrogen. 4. The highest grain yield per 10a (613kg/10a) was resulted from the nitrogen fertilization of 20kg/10a. and the plot of which amount of nitrogen fertilization was 15kg/10a showed the grain yield of 603kg per 10a. But there was not significant difference between two plots mentioned above. 5. Single plant per hill was the most effective for high yield of pearl barley and 3 plants per hill dropped the grain yield of 28.4%.

통일계(統一系) 수도품종(水稻品種)의 저온장해(低溫障害)에 관(關)한 연구(硏究)

최창렬,김문규,조재성,김충수,Choi, Chang-Yoel,Kim, Moon-Kyu,Jo, Jai-Seong,Kim, Choong-Soo 충남대학교 농업과학연구소 1977 Korean Journal of Agricultural Science Vol.4 No.1

$Indica{\times}Japonica$형(型) 수도품종(水稻品種)의 저온발아성(低溫發芽性)과 유묘기(幼苗期)의 저온(低溫)에 의(依)한 장해(障害)를 구명(究明)하기 위(爲)하여 유일외(流一外)29개(個)의 품종(品種)을 $10^{\circ}C$ 및 $15^{\circ}C$ 등(等)에서 발아시험(發芽試驗)하는 한편 유일외(流一外)5개(個) 품종(品種)을 15일간(日間) pot하여 재배(栽培)하여 $5^{\circ}C$ 및 $15^{\circ}C$에서 각각처리(各各處理)한 15 일(日) 후(後)에 모의 생육(生育) 조사(調査)하였던 바 그 결과(結果)를 요약(要約)하면 다음과 같다. 1. $10^{\circ}C$에서는 이리(裡里) 323호(號), (水原) 253호(號), 이리(裡里) 325호(號), 밀양(密陽) 22호(號), 수원(水原) 251호(號) 및 수원(水原) 267호(號)등 품종(品種)은 70% 이상(以上)의 발아율(發芽率)을 보였고, 도도로끼와세, 밀양(密陽) 23호(號), 유신(維新), 이리(裡里) 328호(號) 및 이리(裡里) 329호(號)등 품종(品種)은 10% 이하(以下)의 낮은 발아율(發芽率)을 보였다. 2. $15^{\circ}C$에서는 수원(水原) 262호(號)는 100%의 발아율(發芽率)을 보였으며, 밀양(密陽) 22호(號), 도도로끼와세, 유일(流一), 밀양(密陽) 29호(號) 수원(水原) 258호(號), 밀양(密陽) 23호(號), 밀양(密陽) 24호(號), 밀양(密陽) 28호(號) 및 밀양(密陽) 21호(號)등 품종(品種)은 90% 이상(以上)의 높은 발아율(發芽率)을 보였던 반면(反面) 이리(裡里) 328호(號), 이리(裡里) 329호(號), 진흥(振興) 및 미네히까리 등 품종(品種)은 50% 이하(以下)의 낮은 발아율(發芽率)을 보였다. 3. 발아율(發芽率)과 평균발아(平均發芽) 일수(日數)를 감안(勘案)할 때 밀양(密陽)22호(號) 및 이리(裡里) 323호(號)가 저온발아성(低溫發芽性)이 높은 품종(品種)이라고 보겠으며 $Indica{\times}Japonica$형(型) 품종(品種)의 저온아성(低溫芽性) 정도(程度)는 Japonica형(型) 품종(品種)들에 비(比)해 반드시 낮지 않았다. 4. $1^{\circ}C$에서 유묘(幼苗)가 6시간(時間)은 노출(露出)되어 있어도 생육(生育)에 거의 영향(影響)을 받지 않았으며 12시간(時間) 노출(露出)되었을 경우(境遇) 품종(品種)에 따라 잎이 시드는 경향(傾向)을 보였으나 다시 정당온도(正堂溫度)를 유지(維持)할 경우(境遇) 회복(回復)되었다. 유묘(幼苗)가 저온(低溫)에 노출(露出)되었을 경우(境遇) 잎이 시드는 정도(程度)는 Japonica형(型) 품종(品種)인 밀양(密陽) 15호(號)가 $Indica{\times}Japonica$형(型) 품종군(品種群)에 비(比)현저(顯著)히 낮았다. 5. 조생유일(早生幼一), 유일(幼一) 및 유신(維新)의 유묘(幼苗)는 $1^{\circ}C$에서 36시간(時間) 처리(處理)되었을 경우(境遇) 70% 그리고 72시간(時間) 처리(處理)에서는 100% 고사(枯死)하였으며 약온처리(藥溫處理)에서도 75% 이상(以上) 고사(枯死)하였던 반면(反面) 밀양(密陽) 15호(號)는 72시간(時間) 처리(處理)되었을 경우(境遇) 65%의 고사율(枯死率)을 보였다. 6. 공시(供試)된 전체품종(全體品種)은 24시간(時間) 내지 36시간(時間) 처리(處理)에서 지상부(地上部) 및 지하부(地下部) 생육(生育)의 현저(顯著)한 감퇴(減退)를 보였고 감퇴정도(減退程度)는 처리시간(處理時間)이 길어짐에 따라 현저(顯著)히 심(甚)하였다. An expriment was conducted to determine the rate of germination under low temperature and effects of low temperature on seedling of varieties derived from the cross between Indica and Japonica type of rice. Total of 30 varieties including leading variety, Tongil, were germinated at the temperature of $10^{\circ}C$. and $15^{\circ}C$. to determine the rate of germination, and six varieties also including Tongil were planted in pot, and seedlings were exposed to the temperature of $5^{\circ}C$. and $1^{\circ}C$. for 15 days and damage of plant growth due to low temperature was observed. 1. Under the condition of $10^{\circ}C$., varieties such as Iri #323, Suwon #253, Iri #325, Milyang #22, Suwon #251, and Suwon #267 were showing over 70 percent of germination ratio, while varieties, Dodolokiwase, Milyang #23, Yusin, Iri #328, and Iri #329 were below 10 percent in germination ratio. 2. Under the condition of $15^{\circ}C$., variety Suwon #262 was shown 100 percent of germination and varieties such as Milyg an#22, Dodlokiwase, Tongil, Milyang #29, Suwon #258, Milyang #23, Milyang #24, Milyang #28 and Milyang #21 were over 90 percent in germination ratio. However, varieties such as Iri #328, Iri #329, Jinheung, and Minehikari were below 50 percent in germination rate. 3. Considering the germination rate and average days required to germination, Milyang #22 and Iri #323 were highly resistant varieties to low temperature. The rate of germination of varieties from the cross between Indica and Japonica under low temperature was not always lower than that of varieties from Japonica type of rice. 4. Most of the seedlings of varieties used were quite resistant to $1^{\circ}C$. at least for six hours. However, leaves of rice were exposed to the the temperature of $1^{\circ}C$. for 12 hours, and the withered leaves were recovered soon when put in under normal temperature. The degree of leaf withering under low temperature was lower in Milyang #15, Japonica type than in varietieties belonging to $Indica{\times}Japonica$ type of rice. 5. When the seedlings of varieties such as Josaengtongil, Tongil and Yusin were exposed to the temperature of $1^{\circ}C$. for 36 hours, 70 percent of leaves were withered and when the time of expose were doubled, the leaves were completely died. When the temperature was fluctuated, over 75 percent of leaves were died, while 65 percent of leaves of Milyang #15 were died when exposed to $1^{\circ}C$, for 72 hours. 6. Significant growth retardation was observed for all entries when exposed to $1^{\circ}C$. for 24 to 36 hours. The growth retardation was apparently increased as the time of expose was extended.

二毛作畓에 있어서 水稻移秧機의 實用化에 關한 研究

金聲來(Soung-Rai Kim),金映來(Young-Rae Kim),曺在星(Jai-Seong Jo),李相祐(Sang-Woo Lee) 충남대학교 농업과학연구소 1977 農業技術硏究報告 Vol.4 No.1

統一系 水稻品種의 低溫障害에 關한 研究

崔彰烈(Chang-Yoel Choi),金文圭(Moon-Kyu Kim),曺在星(Jai-Seong Jo),金忠洙(Choong-Soo Kim) 충남대학교 농업과학연구소 1977 農業技術硏究報告 Vol.4 No.1

播種期移動이 Indica親水稻品種/系統의 出穗期의 生態的 變異에 미치는 影響

曺在星 충남대학교 농업과학연구소 1975 農業技術硏究報告 Vol.2 No.2

This experiment was carried out to obtain some imformations about the ecological variations of the heading time of the newly breeded Indica x Japonica varieties/pedigrees according to the seasonal changes of the seeding date, day length and temperature. The results obtained are summarized as follows; 1) At all varieties, days to heading showed a straight reduction according as the seeding time was delayed. 2) At the group of Japonica varieties, the days to heading of early maturing varieties were much shortened and that of medium or late maturing varieties were little or not shortened under high temperature condition but at the group of Indica x Japonica varieties/pedigrees, days to heading were significantly elongated under high temerature condition. 3) At the group of Japonica varieties, the effect of the short day condition on the days to heading was significantly high at the medium and the late maturing varieties than at the early maturing varieties, however, the short day effect on the reduction of days to heading was not related with the earlyness of each varieties at the group of Indica x Japonica varieties/pedigress. 4) Days to heading of all varieties under the high temperature condition were longer than that under the ordinary culture. On the other hand, the days to heading of Japonica varieties under the short day treatment were shorter than the days to heading of ordinary culture but at the group of Indica x Japonica varieties/pedigrees, the days to heading under the short day treatment were longer than ordinary culture. 5) At both varieties groups, the days to heading at each seeding time were significantly correlated with days to heading at ordinary cultivation. 6) At the group of Japonica varieties, relatively high correlation(p=0.1) was recognized between the days to heading by delay of seeding time, but at the group of Indica x Japonicava rieties/pedigrees, correlation between the ordinary heading date and the shortening rate of days to heading was very low.

氣象要因이 水稻의 生育 및 收量에 미치는 影響

曺在星,李鍾喆 충남대학교 농업과학연구소 1975 農業技術硏究報告 Vol.2 No.1

6 years data on the plant growth and grain yield of 13 rice varieties were investigated to define the relations between meteological conditions and plant growth of rice including grain yield. The results obtained are summarized as follows; 1. Variation of average temperature by years showed great number at early and middle July, middle August and early November, however smallest figure at late June and late July. And that of sunshine hours by years were least at late June and late July, and largest at middle July. 2. Among rice yield components variation of panicle number per hill by years was biggest and that of 1000 grain weight least. Rate of variation of plant growth and rice yield was different by rice varieties. 3. Direct effects on rice yield was greatest at maturing ratio and next at 1000 grain weight. The effects of yield factor on the rice yield wers different by years. 4. Higher temperature and longer sunshine delayed the miaxmum tillering stage but shortened the days from seeding to heading. 5. A significant negative correlation was recognized between the number of panicles per hill and average temperature of 11 to 40 days after transplanting, and number of grains per panicle was correlated with the average temperature of 11 to 70 days after transplanting. High temperature before heading time showed atime decreased maturing ratio. 6. Accumulated temperature was highly correlated with 1000 grain weight in all season. Highest positive correlation was recognized between grain yield of rice and average temperature of 61 to 70 days after transplanting but correlations between rice yield and avaerge temperature after heading stage were negative. 7. Highly significant correlations were confirmed between maturing ratio and sunshine hours of 31 to 50 days as well as 61 to 70 days after transplanting, and maturing ratio was highly correlated with accumulated hours of sunshine. Correlation between rice yield and hours of sunshine was significant at 51 to 60 days after transplanting.

율무栽培에 關한 硏究

崔彰烈,曺在星 충남대학교 농업과학연구소 1976 農業技術硏究報告 Vol.3 No.1

These studies were carried out to find out the most reasonable planting density and adequate amount of nitrogen fertilizer for the pearl barley, and results obtained are summarized as follows; 1. The planting densities affected neither the heading date nor the maturing date of pearl barley. 2. The planting density of 90cm X (30cm+30cm) was the most adequate for high yield and that of 40cm×20cm which was the most densely planted plot in this experiment showed the lowest grain yield. 3. The height and weight of stem were significantly increased by increased fertilization of nitrogen. 4. The highest grain yield per 10a (613kg/10a) was resulted from the nitrogen fertilization of 20kg/10a, and the plot of which amount of nitrogen fertilization was 15 kg/10a showed the grain yield of 603kg per 10a. But there was not significant difference between two plots mentioned above. 5. Single plant per hill was the most effective for high yield of pearl barley and 3 plants per hill dropped the grain yield of 28.4%.