• 한국작물학회:학술대회논문집
• /
• 한국작물학회 2017년도 9th Asian Crop Science Association conference
• /
• pp.71-71
• /
• 2017

Stable stand establishment is pre-requisite in direct rice seeding system for obtaining optimal yield of rice crop in rain-fed and waterlogged areas. Anaerobic condition on waterlogged soil causes low germination which significantly reduces crop yield. Due to low availability of tolerant genetic material for anaerobic germination, there is urgent need to evaluate rice germplasm for better germinability under anaerobic conditions. Seeds of the 185 rice accessions were evaluated for germination vigor and coleoptile length under anaerobic conditions. The variation among germplasm was tested for significance using analysis of variance and various multivariate components. Significant level of variation was observed among all accessions for germination vigor and coleoptiles length. Although highest mean values for coleoptiles length (2.1cm) and germination rate (60%) were observed in japonica accessions but maximum coleoptile length (4.68cm) and germination rate (96%) was found in indica genotype CO18. A highly significant and positive correlation was also observed between germination vigor and coleoptiles length, which signify the importance of elongated coleoptile under anaerobic conditions. The PCA analysis illustrated that 97.24% variation was accounted by PC1 while PC2 and PC3 explained 2.54% and 0.24% variation for germination vigor and coleoptile length. PCA scattered plot divided the accessions in four various groups. All AG tolerant accessions were included in group I. Likewise in the case of cluster analysis, two major clades (I and II) were formed. All accessions showing >40% germination rate were included in clade I, whereas all other accessions with <40% germination rate were grouped in clade II. Further more highly tolerant accessions (>80% germination) were grouped in sub-cluster IA.

• 한국작물학회지
• /
• 제48권1호
• /
• pp.1-7
• /
• 2003

In spite water direct seeding cultivation of rice has advantages in terms of laborsaving and cost-down, it demonstrates uneven seedling establishment and difficult weed management. To select an applicable mat for mulching system of water seeded rice, weed occurrence, growth and yield performances of rice, and soil temperature were evaluated in several kinds of biodegradable mulching material. Field studies were conducted at the experimental farm of National Crop Experiment Station in 1999 and 2000. Among the mats tested in 1999, Safer-mat had the greatest effect on inhibiting weed occurrence and Lawn-mat demonstrated the least efficacy of weed control (EWC) value. In Safer-mat treatment, Ludwigia prostrata was the dominant weed species but Echinochloa crus-galli was not observed. Different kinds of mulching material from the mats studied in 1999 were tested in 2000. Biodegradable polyester (PES) coated on the recycled paper for newspaper press (RP) treatments showed similar or higher EWC values than non-mulched broadcast seed rice with 2 times of herbicide application (BC-herbicide) and Safer-mat that was the most effective mat on preventing weed appearance in 1999. Immediately after mat mulching on the surface of paddy soil, five pregerminated rice seeds were manually sown in each 3cm-hole formerly punctured at 30${\times}$14 cm spacing in 2000. All the 3 kinds of mulching material tested in 2000 had better seedling stand than BC-herbicide treatment. Rice yield in PES coated with 10 thickness on RP (PES10 $\mu\textrm{m}$＋RP) was a little higher than in BC-herbicide treatment but the former produced less panicles in unit land area than the latter. PES10 $\mu\textrm{m}$＋RP demonstrated a great effect on raising soil surface temperature than non-mulching treatment throughout the period of seedling establishment.

• 한국환경과학회지
• /
• 제31권9호
• /
• pp.793-801
• /
• 2022

This study was carried out to provide basic data for logical forest management by developing a site index curve reflecting the current growth characteristics of Cryptomeria japonica stands in Korea. The height growth model was developed using the Chapman-Richards, Schumacher, Gompertz, and Weibull algebraic difference equations, which are widely used in growth estimation, for data collected from 119 plots through the 7th National Forest Inventory and stand survey. The Chapman-Richards equation, with the highest model fit, was selected as the best equation for the height growth model, and a site index curve was developed using the guide curve method. To compare the developed site index curve with that on the yield table, paired T-tests with a significance level of 5% were performed. The results indicated that there were no significant differences between the site index curve values at all ages, and the p-value was smaller after the reference age than before. Therefore, the site index curve developed through this study reflects the characteristics of the changing growth environment of C. japonica stands and can be used in accordance with the site index curve on the current yield table. Thus, this information can be considered valuable as basic data for reasonable forest management.

• 생물환경조절학회지
• /
• 제20권1호
• /
• pp.21-26
• /
• 2011

고랭지 시금치의 여름철 수경재배에 적합한 품종과 육묘 배지의 선발, 적정 양액조건의 구명 및 시설비가 적게 들고 생산성이 높은 수경재배 방식의 개발을 위하여 본 연구를 수행하였다. 고랭지에서 여름철 수경재배에 적합한 시금치 품종은 '퀸토'로 다른 품종에 비하여 생육이 좋고 수량도 많았다. 시금치의 생육에 적합한 양액의 조건은 pH 6.0, EC $2.0dS{\cdot}m^{-1}$ 및 $NH_4-N$의 비율은 30%이었다. 육묘용으로 피트모스와 펄라이트를 7:3의 용적비로 혼합한 상토를 200공 트레이에 채우고 시금치 종자를 파종하여 육묘한 경우 우레탄스펀지나 암면 플러그에서 육모한 것보다 입묘율이 높았다. 이렇게 육묘한 묘로 수경재배를 한 결과 혼합상토로 육묘한 경우의 수량은 암면 및 우레탄스펀지에 비하여 18% 및 24%가 증가하였다. 토양 위에 비닐을 깔아 만든 박막재배 베드에 lcm 두께로 혼합배지(피트 : 펄라이트 = 7 : 3)를 채운 후 스티로폼 정식판을 올려놓고 시금치를 재배할 경우 담액재배에 비하여 초장은 18% 길었고 수량은 9% 증가하였으며, 근권 온도 pH 및 EC는 담액재배와 비슷한 양상으로 변화하였다.

• 한국잠사곤충학회지
• /
• 제17권1호
• /
• pp.1-26
• /
• 1975

These studies were attempted to find out the optimum silk reeling system by use of automatic silk reeling machine to increase raw silk yield and reeling efficiency with various silk reelable cocoons. The obtained results are as follows; 1. The mean silk reelability ratio(X)of the Korean cocoons during the last ten years was 61 per cent, beside 64.7 per cent in autumn cocoon and 57.3 per cent in spring cocoon. However, the ratio variation of autumn cocoons was larger than that of spring cocoons. 2. A positive correlation between cocoon filament breaks during its process and silk reelability levels was shown to be significant. The cocoons of both poor and good reelability evidenced "J" shape distribution on the filament break graph by the order of reeling cocoon end. Many bave breaks were found at the inner shell of the cocoons, or in case of poor reelability cocoons. 3. The morphology of broken cocoon ends during the process was classified into A, B, C, D, E and F types, The occurrence of B type was majority, but that of F type was minority among them. 4. In case of the cocoon cooking, H-type ion-exchanged soft water was better for good reelability cocoons, Na and H-type ion exchanged neutral soft water for those of fair reelability, and alkaline (Na-type) soft water for those of poor reelability, respectively. 5. The modification of cooking water by mixing the above different types of water (50％ Na-type and 50％ H-type passed by standard natural water; 75％ Na-type and 25％ H-type passed by hard natural water; 25％ Na-type and 75％ H-type passed by soluble natural water) made higher yield of raw silk with tess breaks of thread. 6, In case cocoon ends groping water included sodium hexametaphosphate as much as 800 ppm. the groping efficiency and raw silk yield of cocoon was improved. The effect was pronounced in case of poor reelability cordons. 7. The most reasonable cocoon cooking and silk reeling condition for automatic silk reeling process were observed to be rather incomplete cook with good reelability cocoons and optimum cook with poor reelability cocoons succeeded by the reeling bath temperature of 45$^{\circ}C$, 8. The reasonable silk reeling velocities were observed to be about 150m per min. for good reelability cocoons, 120m per min. for fair reelability ones and 90 to 120m per min. for poor reelability ones. 9. In order to improve the raw silk yield of cocoons and reeling efficiency, the cocoon stand-by-ratio for reeling should be kept at the level of 40 per cent for good reelability cocoons or at 60 per cent for poor reelability ones beside necessary end found cocoon condition.

• 한국산림과학회지
• /
• 제86권3호
• /
• pp.365-377
• /
• 1997

미국 테네시주 컴벌랜드 고원의 대부분은 혼합 침엽수림으로 되어 있어 기존의 성장과 산출 예측 방식을 적용하기 어렵다. 또한 그들의 역사가 알려져 있지 않을 뿐더러 많은 부분이 동령림이 아니기 때문에 성장과 수확 예측 모델을 만드는데 있어서 지위지수를 변수로 사용하는 것이 제한되어 있다. 임지형(landtype)은 거의 같은 수확을 내는 임지를 포함하도록 고안되어 있기 때문에 이런 혼효림에서 지위지수 대산 사용될 수 있다. 임지형을 사용한 식생 결정을 위해, Chi-square로 임지형과 임형(forest type)과의 의존성을 검사하였다. 임지형 사이에서 수확의 유의성은 회귀분석과 분산분석을 이용하여 검사되었다. 흉고단면적성장(basal area growth)은 Moser and Hall(l969)이 개발한 비선형 모델에 적용되었다. 또한 흉고단면적성장과 재적성장은, 임지형과 임지형급(landtype class)에 의한 선형 회귀분석을 통해 최초 총 흉고단면적과 최초 재적에 관한 하나의 함수로서 예측되었다. 분산분석으로 임지형에 따른 흉고단면적성장과 재적성장의 유의성을 검사하였다. 지위급(site class)과 임지형의 유의성은 Chi-square로 검사되었다. 표본 강도가 낮아 검증이 의심스러웠음에도 불구하고, 식생형 (vegetation type)은 연구 지역 내 임지형과 관계된 것으로 보인다. 본 연구에서 임지형 간의 수확은 통계학적인 유의성이 발견되지 않았다.

• 한국초지조사료학회지
• /
• 제27권4호
• /
• pp.269-274
• /
• 2007

본 연구는 논에서 월동사료작물로 재배되고 있는 내한성 이탈리안 라이그라스(Lolium multiflorum Kospeed)의 입모율 향상과 건물수량 증대를 위해 우리나라 중부지역에 알맞은 파종방법을 구명하고자 본시험을 수행하였다. 파종시기는 총체벼 수확 후 9월 25일에 파종하였으며 파종방법은 로타리-조파-진압, 로타리-산파-진압, 로타리-산파, 로타리-산파-가벼운 로타리, 무경운산파-가벼운 로타리) 5처리를 난괴법 3반복으로 수행하였다. 파종방법별 입모율은 조파에 비해 산파는 12.0% 감소하며, 월동율에 있어서도 17.0% 감소하였다. 특히 관행 호밀 파종법으로 사용하는 로타리-산파-가벼운 로타리 파종법은 다른 산파방법 보다 입모율이 65.2% 수준으로 낮아지며, 월동율도 6.7% 감소하였다. 파종방법별 건물수량에서 산파는 6,281 kg/ha로 조파 8,151 kg/ha에 비해 71% 수준으로 낮게 나타났다(p<0.05), 산파방법 중 "로타리-산파-진압" 파종방법은 7,166 kg/ha로 조파 대비 87.9% 건물수량을 높일 수 있는 파종방법이었다. 그러나 관행 파종법인 "로타리-산파-가벼운 로타리" 파종방법은 조파에 비해 건물수량이 68% 수준으로 유의성이 인정되었다(p>0.05). 그러나 사료가치에서 파종방법별 유의성은 없었다. 이상의 결과를 종합하여 볼 때 총체 벼 후작으로 이탈리안 라이그라스 재배시 "로타리-산파-진압" 파종방법이 가장 적합한 방법으로 추천된다.

• Weed & Turfgrass Science
• /
• 제6권3호
• /
• pp.196-202
• /
• 2017

흑미를 이용한 무논점파 재배방법에 따른 입모, 수량, 품질특성 등을 구명하고 효과적인 잡초방제체계를 결정하여 재배안정화를 유도함으로써 흑미를 이용한 무논점파 재배의 보급 확대를 위한 기초자료를 제공하고자 수행하여 얻어진 결과는 다음과 같다. 흑미 무논점파 재배에서의 효과적인 잡초방제체계는 제초효과가 높고 약해에도 안전하였던 bromobutide thiobencarb (파종 전 5일) followed by bensulfuron mefenacet thiobencarb (파종 후 12일) 체계처리가 유리할 것으로 판단되었다. 파종시기 및 재식밀도에 따른 흑미의 입모수는 파종시기가 늦어지고 재식밀도가 높아질수록 증가하였으며 출수기는 파종시기가 늦어질수록 지연되었으나 재식밀도별로는 차이가 나타나지 않았다. 흑미의 가장 중요한 품질요소인 안토시안함량은 파종시기가 늦어지고 재식밀도가 낮아질수록 높아지는 경향이었으며 완전 착색 현미수량은 5월 30일과 6월 10일 파종 $3.3m^2$당 80주에서 이앙재배 대비 99% 수준으로 가장 높게 나타났다. 이상의 결과들을 종합해 보면 흑미를 이용하여 무논점파 재배를 할 경우 적정 재식밀도는 $3.3m^2$당 80주였고 중만생종 품종으로 사료맥류 후작인 6월 10일 파종까지는 수량감소가 거의 없어 안전하게 재배가 가능하며 식용맥류 후작인 6월 20일 파종에서는 중만생종 품종은 지양하고 조생종 품종을 선택하여야만 비교적 안전하게 재배가 가능할 것으로 판단되었다.

• 한국작물학회지
• /
• 제53권3호
• /
• pp.292-296
• /
• 2008

Clay-coated rice seeds (clay-coated seeds A and B) were directly sown on dry paddy and their growth and yield were compared with the normal drill-sown seeds on dry flat paddy. In clay-coated seeds, germination was 1 day earlier and the emergence rate was higher up to 5% than that of normal drill-sown seeds. But the apparent number of seedling stand per $m^2$ was lower than that of normal drill-sown seeds, which is due to the smaller amount of seeding in clay-coated seeds. At the early growth stage, the plant height of clay-coated seeds A was taller than that of drill-sown seeds, while the plant height of clay-coated seeds B was 0.7 cm shorter than that of drill-sown seeds. At the late growth stage, however, the difference was insignificant in both cases. The maximum tillering stage was 10 days earlier in drill-sown seeds. Lodging index was the lowest in clay-coated seeds B and there was no difference between clay-coated seeds A and drill-sown seeds. The ratio of stem base weight, culm diameter and culm wall thickness were higher in clay-coated seeds, while the lower internodes (4th, 5th and 6th) length was shorter in claycoated seeds than in drill-sown seeds. In clay-coated seeds, the number of panicle per $m^2$ was smaller, while the number of spikelet per panicle was a little larger than in drill-sown seeds. The rate of ripened grain and brown rice 1,000 grain weight were lower in the clay-coated seeds, thus the yield was $98{\sim}99%$ level of drill-sown seeds. Considering that the amount of seeding in clay-coated seeds was two-thirds of that in drill-sown seeds, it is expected that clay coating method could become an additional technique for direct seeding cultivation.

• 한국작물학회지
• /
• 제40권6호
• /
• pp.731-737
• /
• 1995

벼 건답직파재배시 토성이 다른 양토와 사양토에서 질소분시방법 차이가 생육형질 및 수량에 미치는 영향을 검사하고자 화성벼를 4월 27일에 평면줄뿌림하여 시험을 수행했던 결과는 다음과 같다. 1. 입묘수는 토성 및 질소분시방법에 일정한 경향이 없이 159~177개/$m^2$ 의 분포를 보였다. $m^2$ 당 수수는 양토가 사양토보다 많았으며, 사양토, 양토 모두 추비중점시비 (3엽기-7엽기-수비=40-30-30% 및 기비-3엽기-7엽기-수비=10-30-30-30%)가 관행 시비방법(기비-5엽기-수기=40-30-30%)보다 많았다. 2. 생육시기별 엽색, 출수기엽면적지수 및 건물중은 토성간에는 양토가 사양토보다 높았고, 질소분시방법간에는 추비중점시비는 관행보다 높았으나 20%감비와 완효성 시료시용은 관행보다 낮았다. 3. 도복지수는 추비중점시비에서 간장이 크고 협절중이 낮아 관행보다 높은 도복지수를 보였고, 이 결과 포장도복도 추비중점시비에서 3정도 발생하였다. 4. 추비중점시비는 관행에 비하여 등숙비율이 약간 낮았고 천립중은 비슷하였으며, 현미에서 완전미율이 낮은 반면 청미와 미숙립율이 높았다. 5. 수량은 관행대비(사양토 5.08t/ha, 양토 5.22t/ha) 추비중점시비에서 사양토는 7~9%, 양토는 6~9% 증수되었다.