The increase in temperature due to climate warming is predicted to affect crop yields in the future. Until now, various types of OTC (open top chamber) that simulate the future climate condition have been developed and used to study the effect of temperature increase due to global warming on maize growth. However, in most OTCs, high equipment and maintenance costs were required to artificially increase the temperature. This study was carried to develop a cost-effective and simple OTC suitable for climate warming experiments for forage maize. Three octagonal OTCs with a height of 3.5 m × a diameter of 4.08 m and a partially covered top were constructed. The lower part of OTC covered film was opened at a height of 26 cm (OTC-26), 12 cm (OTC-12) from the ground surface, or not opened (0 cm, OTC-0). Mean air temperatures during the daytime on a sunny day in OTC-0, OTC-12 and OTC-26 increased to 3.23℃, 1.33℃, and 0.89℃, respectively, compared to the ambient control plot. For a pilot test, forage maize, ‘Gwangpyeongok’ was grown at OTCs and ambient control plots. As a result, in the late maize vegetative growth phase (July 30), the plant height was increased more than 45% higher than the ambient control plot in all OTC plots, and the stem diameter also increased in all OTC plots. These results indicate that it is possible to set the temperature inside the OTC by adjusting the opening height of the lower end of the OTC, and it can be applied to study the response of forage maize to elevated temperature. An OTC, with its advantages of energy free, low maintenance cost, and simple temperature setting, will be helpful in studying maize growth responsiveness to climate warming in the future.

This study investigated on the chemical components, quality characteristics, antioxidant compounds, and activity of maize hybrids according to the cultivar, and breeding maize seeds crossed with seed and pollen parent. The moisture, crude fat, crude ash, crude protein, carbohydrate, and amylose contents of maize hybrids were significantly different among cultivars, and seeded and pollinated maize. The L-, a- and b-value of maize hybrids were 39.81~47.21, －0.01~0.55 and 5.85~18.47, respectively. Water binding capacity, water solubility index and swelling power were 123.29~153.32, 4.69~5.76 and 20.11~21.47%, respectively. The phenolic compounds and radical scavenging activity of maize hybrids were significantly different among cultivars, and seeded and pollinated maize. Total polyphenol and flavonoid contents of maize hybrids were 1,335.41~1,876.29 μg/g and 184.24~453.95 μg CE/g, respectively. The DPPH and ABTS radical scavenging activities were 171.75~239.16 and 299.44~364.09 mg TE/100 g, respectively. As a result, it could be used as a basic data for cultivating phenol compounds and antioxidant activity in maize breeding.

This study was conducted to investigate the growth characteristics of the shoot and roots and to analyse the morphological characteristics of roots of waterlogging resistant and susceptible maize inbred lines. Six maize inbred lines were treated with waterlogging for 10 days at V3, and the degree of leaf senescence was evaluated for waterlogging resistance. As a result of waterlogging resistance evaluation, KS85 was the most damaged inbred line with 3.33 senescence leaves and 5.54 degree, and KS141 was the least damaged inbred line with 1.33 senescence leaves and 3 degree. At 20 days after treatment, the effect of waterlogging stress on the shoot dry matter accumulation of KS85 and KS141 were decreased by 86.1% and 77.0%, respectively, compared to the control. Similarly, root dry matter accumulation of KS85 and KS141 were decreased by 77.6% and 65.0%. As a result of SEM photographs of the nodal roots of the two maize inbred lines, the thickness of cortex of KS141 was thicker than that of KS85, and the distortion of the cortex was observed in KS85 at 20 days after waterlogging. It was concluded that the thickness of cortex was related to maize waterlogging resistance.

The physicochemical properties of high-pressure homogenized (microfluidized) maize starch with different preheating temperatures (50, 60oC), levels of pressure (34.5, 69, 138 MPa), and numbers of pass (1, 2, 3 pass) were examined in this study. The enzyme susceptible starch (ESS) content, morphological property, X-ray diffraction, and Rapid Visco Analyzer (RVA) profile of starch were significantly altered via increasing the number of passes and preheating temperatures. The amount of ESS and the diffraction pattern of starch indicated that the granular crystalline structure of starch was severely damaged by increasing the number of passes and preheating temperatures. The morphology of starch granule was changed from angular to spherical shape with the damaged surface as the pressure increased. Moreover, damaged starch particles gathered to form a larger mass when treated at a higher temperature with the increasing number of passes, indicating that different types and extents of damage occurred. The RVA profile of starch showed a moderate peak viscosity with increased pasting stability against shear thinning similar to that of cross-linked starch as the number of passes and preheating temperatures increased. These results suggested that microfluidization combined with preheating might be used as a potential alternative method for the modification of starch such as cross-linked starch.

This study was conducted to secure basic information for corn processing by comparing the quality characteristics according to maize cultivars and kernel types (dent, intermediate, flint-like). As a result of analyzing 15 cultivars, a range of measurements were observed: 100-kernel weight, 22.89~35.63 g; moisture, 7.57~8.42%; crude protein, 8.46~11.45%; crude lipids, 3.26~4.83%; Hunter’s L-value, 83.70~86.79; a-value, 2.61~5.49; b-value, 22.01~28.15; and total carotenoids, 6.74~17.07 μg/g. Significance among the cultivars was shown in all quality characteristics (p<0.001), but the significance among the kernel types was found only in crude protein (p<0.005), crude fat (p<0.001), and Hunter’s L-value (p<0.05). The hardness of maize was decreased proportionally to the soaking time for all maize cultivars (p<0.001). In particular, with the same soaking time for different kernel types, the hardness difference was shown in the order of flint-like > dent ≒ intermediate. It was confirmed that the decrease in the hardness of flint-like kernel of close to that of hard-type starch was slowed compare dent and intermediate kernels. So it is expected the some characteristic of kernel types will contribute to the appropriate customized use of the developed cultivars.

수원지방에서 콩과 옥수수에 대한 잠재적인 해충으로 밤나방과의 열대거세미나방(Spodoptera frugiperda)과 담배거세미나방(S. litura), 파밤나방(S. exigua), 콩은무늬밤나방(Ctenoplusia agnata), 뒷흰가는줄무늬밤나방(Mythimna loreyi ), 뒷흰날개담색밤나방(Athetis dissimilis), 꼬마 담색밤나방(A. lepigone)을 수컷 성충의 날개 무늬와 생식기 형태 및 미토콘드리아 시토크롬 옥시다제 1 유전자 부분 염기서열을 비교하여 해당 종들을 동정하였다. 꼬마담색밤나방을 제외한 6종에 대해서는, 2019년 성페로몬트랩에서 관찰된 연중 밀도변동 자료와 온도에 따른 발육과 생식 모델들을 이용하여 관찰 세대로부터 다음 세대 성충의 발생시기를 예측한 자료로, 해당 종이 1년 안에 성충 세대가 몇 회 연속하여 발생할 수 있는가 추정하였다. 열대거세미나방은 7월 27일부터 10월 31일까지 포획되었는데, 수원 지방의 자료만으로는 3회 성충이 발생하는 것으로 추정되었다. 그러나 다른 지방에서 관찰된 6월 중하순의 유충 발생 자료를 고려하여, 수원지방에도 연중 4회 성충이 발생할 수 있을 것으로 추정되었다. 담 배거세미나방은 5월 29일부터 11월 6일까지 포획되었고, 파밤나방은 5월 14일부터 11월 6일까지, 콩은무늬밤나방은 5월 26일부터 10월 25일 까지, 뒷흰가는줄무늬밤나방은 5월 31일부터 11월 23일까지 포획되었다. 이들 4종도 성충 세대가 연중 최소한 4회 발생할 것으로 추정되었다. 뒷흰날개담색밤나방은 5월 26일부터 9월 11일까지 포획되었고, 연 2회 발생이 추정되었다. 두 종의 Athetis속 나방을 제외한 다른 다섯 종들의 첫 발생 성충세대들은 다른 지역으로부터 비래했을 것으로 가정되었다.

This study aimed to discuss the optimal seeding and harvesting dates with growing degree days(GDD) via meta-data of whole crop maize(WCM). The raw data (n=3,152) contains cultivation year, cultivars, location, seeding and harvesting dates collected from various reports such as thesis, science journals and research reports (1982-2012). The processing was: recording, screening and modification of errors; Then, the final dataset (n=121) consists of seeding cases (n=29), and harvesting cases (n=92) which were used to detect the optimum. In addition, the optimal periods considering tolerance range and GDD also were estimated. As a result, the optimum seeding and harvesting periods were 14th April ~ 3rd May and 15th August ~ 4th September, respectively; where, their GDDs were 23.7~99.6℃ and 1,328.7~ 1,602.1℃, respectively. These GDDs could be used as a judge standard for selecting the seeding and harvesting dates.

한반도 북부 지역에 적응하는 옥수수 품종 개발의 기초연구의 일환으로 2017~2018년 중국 요녕성 동항과 연변주 용정에서 18 품종/교잡계를 파종기, 재식거리 및 시비량 등 관행에 따라 재배하여 출사기 성숙기 반응 및 수량성을 조사하였다. 1. 지역 간의 출사까지의 적산온도 차이가 출사일수의 변이 보다 적으며, 출사일수 차이가 10일 이상인 품종/교잡계는 다청옥, 강다옥, 14GS19/14GS11이었다. 출사일수의 연차변이가 적은 반면 출사까지 적산온도가 큰 경향을 보였다. 2. 동항이나 용정의 적산온도는 북한의 옥수수 숙기 분류기 준에 중간늦종 범위를 벗어나는 늦종 그룹으로 분류할 수 있었다. 용정에서는 북한 성수군 기준의 늦종 재배 가능하며, 동항은 북한의 수풍, 회천, 신포, 양덕, 평강을 잇는 지역에 해당한다. 3. 평균 수량이 10a 당 1,000 kg 이상인 품종은 신황옥 (1,076 kg), 황다옥(1,023 kg), 그리고 중국 비교품종 Xianyu335, Fulai818도 각각 1,013 kg과 1,038 kg이었다. 18개 품종/교잡 계의 대부분이 중간늦종~늦종 군에 분류되었다. 18개 품종/교 잡계의 대부분이 중간늦종~~늦종 군에 분류되었다. 4. 북한의 각 지역별 재배 가능한 성숙군은, 중산지 혜산은 중간종, 북부 선봉은 중간종~중간늦종, 북부 산간인 중강과 동해안 북부 청진지방은 중간늦종~늦종 재배가능지이며, 그 외 지역은 모두 3,000oC 이상으로 늦종 재배에 충분한 적산온도 를 보였다. 북부산간 고지대인 삼지연, 풍산, 장진은 적산온도 2,000oC 이하 지역으로 옥수수 재배가 어려운 지역으로 나타 났다.

본 연구는 강원도에서 육성한 오륜팝콘, 오륜2호, 지팝콘, 기찬팝콘 총 4품종 팝콘 옥수수의 영양성분을 분석하여 비교하였으며, 항목은 일반성분, 무기성분, 지방산, 아미노산, 환원당 및 전분함량을 분석하였다. 건조된 팝콘 옥수수 품종의 수분함량, 회분, 조지방은 각각 11.54-12.54%, 0.97- 1.45%, 2.48-2.62%의 함량을 나타냈다. 조단백질 함량은 9.68-11.75% 이였다. 무기성분으로는 칼륨과 인이 가장 조성비가 높게 나타났으며 칼륨은 228.25-310.46 mg/100 g의 범위로 나타났으며 오륜팝콘이 가장 함량이 높았고, 인의 함량은 276.04-310.00 mg/100 g의 함량을 나타냈다. 지방산은 총 11종이 검출되었으며 linoleic acid의 함량이 전체 지방산 함량의 52.89--55.76%의 분포로 가장 높은 함량을 나타냈고, 그 다음으로 oleic acid(24.31-26.65%), palmitic acid(14.20-15.92%) 인 것으로 나타났다. 아미노산은 품종 별로 총 16종의 아미노산이 검출되었으며, glutamic acid가 전체 아미노산의 17.70-18.52%로 가장 높았고, leucine(12.30-12.54%), proline(10.34-10.92%)의 순으로 조성비가 높게 나타났다. 품종별 환원당 함량은 4.68-5.13% 이였으며, 전분은 42.14-46.14%의 함량을 나타냈다.

열대몬순기후인 캄보디아에서 2011년부터 2013년까지 건기와 우기로 구분하여 사료용 옥수수인 국내 품종인 광평옥과 평안옥 그리고 수입 품종인 CP888과 Loeung Mongkul에 대한 생육과 수량특성을 구명한 결과이다. 출사 소요일수는 건기 재배에 있어서 2011과 2012년 및 2013년에는 큰 차이가 나타나지 않았으나, 우기 재배에서는 2012년이 2011년에 비해 6일이 단축되었으며 품종간 약 2-3 일의 차이를 보였다. 종실 수량은 건기 재배에서 2012년(548-788 kg/10a)이 2011 년(386-505 kg/10a)과 2013년(345-687 kg/10a)에 비해 다소 높았다. 우기 재배에서는 2012년(369-582 kg/10a)과 2011년(221-601 kg/10a)간에 차이를 보이지 않았다. 그러나 품종간 유의한 차이를 보였다. 본 연구결과 우기 재배에서 안정적인 옥수수 수량을 확보하려면 강수량이 높은 8월과 9월 및 10월 보다는 우기 전인 6월과 7월에 파종하는 것이 좋으며, 건기 재배에서는 충분한 관개가 있는 조건에서 12월부터 다음 년도인 2월 말까지가 파 종하는 것이 최대 수량을 확보하는데 유리할 것으로 사료된다.

We used the upland field rotated from matured rice paddy field, which have been used as a rice paddy field long time, for three years from 2015 to 2017. Therefore, this study was conducted for three main purposes. The first was to investigate yearly changes of growth and yield for waxy maize in the organic farming waxy maize at rice paddy-upland rotation system, the second was to investigate yearly changes of soil physical and chemical characteristics of rice paddy field soil in organic farming waxy maize at rice paddy-upland rotation system and the third was to select the suitable varieties for organic farming waxy maize at rice paddy-upland rotation. The test varieties were that 8 varieties of waxy maize of Mibaek 2, Ilmichal, Daehakchal, Chalok 4, Miheukchal, Eolrukchal 1, Heukjinjuchal, Heugjeom 2. For yearly yield, the highest yield was obtained in the first year of 949.6 kg, the second highest was in the third year of 680.6 kg 10a-1, while the second year was the lowest yield (675.4 kg 10a-1). Both varieties of Chalok 4 and Ilmichal showed the highest yield with about 900 kg 10a-1 in the threeyear average of 8 varieties. Solid phase of deep soil was 10% higher than that of top soil. Porosity rate of the top soil (54.7%) was higher than that of deep soil (49.4%), and the porosity in the third year was 2.7% higher than that of the first year. Soil organic matter content was significant different between soil depths and between three years. Soil solid and liquid phase decreased by 1.6% and 4.3%, respectively, compared to the first year, and the gas phase increased by 4.3%. The porosity of the third year was 2.7% higher than that of the first year. The soil organic matter content was 9.5 g kg-1 in the third year compared with 12 g kg-1 in the first year. It has also trend to decrease as the number of years rotated from rice paddy field increased. In the three-year average yields of Ilmichal and Chalok 4 were 898.1 kg 10a-1 and 891.6 kg 10a-1 respectively and the yield of Chalok 4 was greater than the other 7 varieties. We compared and selected the two best waxy maize varieties of Chalok 4 and Ilmichal for rice paddy-upland rotation. When we look at the yearly variation for waxy maize, Waxy maize yield was the highest in the first year and decreased year by year. Therefore, it would be better to restore upland field to rice paddy fields after the first year.