• 한국작물학회지
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• 제48권1호
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• pp.25-30
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• 2003

This research was conducted to compare the dry matter production and the yield productivity among nine soybean cultivars by measuring the photosynthetic ability of the middle and lower leaves at the flowering and the seed development stages. The leaf greenness(SPAD value) were ranged as 32-42 at the flowering stage. Also, They were ranged as 25-40 and 38-51 at the fifth leaf and the seventh leaf, respectively. The photosynthetic ability at the flowering and the seed development stage showed significant differences among soybean cultivars, and the photosynthetic ability at the seed development stage showed higher difference among cultivars than the flowering stage. The variation of the photosynthetic ability at the flowering and the seed development stage also was significant among cultivars. The light saturation point at the flowering stage was about 1500 $\mu$mol $m^{-2}$ $s^{-1}$ PAR, and the seed development stage was about 1000 $\mu$mol $m^{-2}$ $s^{-1}$ PAR. The photosynthesis showed the high negative correlation with the leaf area and the positive correlation with the leaf area ratio. Also, photosynthesis at seed development stage showed positive correlation with grain yields but there was not significant between photosynthesis and yields at flowering stage..

• 한국연초학회지
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• 제11권2호
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• pp.127-134
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• 1989

Several growth characteristics of two ornamental tobacco species, Nicotiana sanderae and N. affinis, were investigated in this study. Also effect of temperature and daylength on the flowering of the tobacco plants were evaluated to obtain basic information on breeding and cultivation. 1. The plants were great in high temperature-long day at the early stage and in low temperature-short day at the late stage of plant growth, for both Nicotana species. At the early growth stage the leaf length N. sanderae was great in high temperature-long day, and that of N. affinis was great in high temperature-short day period, while at the late stage of the plant growth the leaf lengths were more significantly effected by the temperature rather than daylength. Leaf width and leaf shape index were less sensitive to the conditions. 2. For both of the species, the total number of tobacco leaves not much influenced by the temperature and daylength. 3. There were no significant differences for budding and flowering period between the two species, both of which were sensitive to temperature and daylength with more influence by daylength than temperature. 4. Number of floral stalks, number of flower and flowering period were not much influenced by temperature and daylength; however, N. affinis had 2 more floral stalks, 31 more flowers, and 6 day longer flowering period than N. sanderae.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.100-100
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• 2017

FT is one of the major floral activator in plant flowering. FT determines the changing point of time from vegetative stage to reproductive stage. To understand the role of FT homologs in short-day plant soybean, we identified 10 soybean FT homologous genes and named GmFTs. We figured out that 10 GmFT genes were further categorized into three subclades through phylogenetic analysis. Expression analysis of GmFT genes indicated that they might have different functions in photoperiod-dependent soybean flowering. Most of GmFTs, for example, GmFT2a, GmFT2b, GmFT5a and GmFT6 mainly expressed in soybean leaves at short-day condition. However, interestingly GmFT1a and GmFT4 represented opposite expression pattern to other GmFTs. Arabidopsis transgenic plants overexpressing GmFT2a and GmFT5a exhibited extremely early flowering. In contrast, overexpression of GmFT4 delayed flowering of Arabidopsis transgenic plants. The results suggest that GmFT4 has antagonistic role to other GmFTs in soybean flowering. Interestingly, mRNA level of GmFT2a is higher in early flowering soybean accessions than in late flowering ones. Moreover, the highest point of mRNA level of GmFT2a showed the positive correlation with the timing of flowering of soybean accessions. But that of GmFT4 showed opposite pattern. Here, we report that soybean FT homologs might acquire different functions in photoperiod-dependent flowering through the functional diversification during evolution.

• 한국작물학회지
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• 제44권3호
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• pp.221-224
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• 1999

A field experiment was carried out to observe the weed control effects of vetch and to evaluate vetch characteristics on clay loam soil in no-till direct-sown rice-vetch cropping systems. The effects of weed control, forage productivity, and N content of vetch plants were investigated. With the progress of plant growth, density of Chinese milk vetch (Astragalus sinicus L.) gradually decreased, but densities of foxtail and other weeds decreased steeply due to the depression by the over-shaded vetch canopy in a no-till direct-sown rice-vetch cropping paddy field. The vetch density in tillage systems was lower than in notillage cropping systems. Lower vetch density occurred with an increase in foxtail density and other weeds. Weed control effect increased by the progress of vetch growth, which indicated that the vetch canopy over-shaded the weeds. Vetch straw was degraded rapidly submergence after with water at the time of wet sowing of rice. Early harvesting of vetch seed resulted in lower seed germination. To acquire enough seedlings without re-sowing, the harvesting of seed should be delayed at least 28 days after the flowering stage in order to ensure the vetch population is sustainable in a no-till direct-sown rice-vetch cropping system. In order to improve the survival of vetch plants, vetch seeds should germinate from the heading .stage to before the full-ripening stage of rice plants. To enhance the percent of over-wintering survival, vetch seeds should germinate no later than the end of October in southern Korea. The dry weight of vetch plants increased with the progress of vetch growth until the flowering stage but N content decreased for 30 days from before the flowering stage (2.9%) until the ripening stage (1.8%). We concluded that Chinese milk vetch could have an effect on weed control before the flowering stage, sustainability without re-sowing of seed annually, and effective green manure for rice pre-crop in no-till direct-sown rice-vetch relay cropping systems.

• 원예과학기술지
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• 제33권1호
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• pp.61-69
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• 2015

본 연구는 수출용 스탠다드 국화 '백마'의 모의 수송온도와 개화단계에 따른 절화의 품질과 수명에 미치는 영향을 조사하여 적정 수송온도와 수확시기를 구명하고자 실시하였다. 개화 4단계의 '백마' 절화를 수확하여 $5^{\circ}C$에서 24시간 수송한 후 5, 20, $35^{\circ}C$에서 48시간 모의 수송하여 절화의 품질을 조사하였다. 또한 개화 1단계에서 6단계까지의 절화를 수확하여 $5^{\circ}C$에서 72시간 동안 모의 수송한 후 절화의 품질을 조사하였다. 수송온도가 높아질수록 유통박스 내의 $CO_2$ 농도는 급격히 높아졌으며, $O_2$ 농도는 크게 감소하였다. $35^{\circ}C$와 $20^{\circ}C$보다 $5^{\circ}C$에서 수송하는 것이 절화수명이 3.8일 연장되었으며, 잎의 엽록소 함량도 345.7로 가장 많았다. 또한 $35^{\circ}C$보다 $5^{\circ}C$ 수송조건에서 절화의 생체중과 흡수량이 높게 유지되었을 뿐만 아니라 화경도 보존용액에서 8일째에 2.3cm 더 길었다. 개화 6단계보다 개화 1-2단계에서 수확한 절화의 수명이 5.2-5.5일 연장되었다. 그러나, 개화 1단계부터 3단계까지의 절화들은 개화 4-6단계보다 생체중이 낮았을 뿐만 아니라 화경도 1.3-2.5cm 더 작았다. 또한 개화 4-6단계의 절화는 개화 1-3단계의 절화에 비해 상대적으로 흡수량이 많은 것으로 나타났다. 따라서 일본 수출용 '백마'는 설상화의 개화상태와 품질을 고려한다면 개화 4단계의 절화를 $5^{\circ}C$ 조건에서 수송하는 것이 가장 바람직하다고 판단되었다.

• 한국약용작물학회지
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• 제2권1호
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• pp.74-80
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• 1994

참당귀(當歸)의 생육단계(生育段階)에 따른 $GA_3$, IAA 및 ABA의 함양변화(含量變化)를 구명(究明)하여 생육조절물질(生長調節物質)을 이용(利用)한 추대억제방법(抽臺抑制方法)의 확립(確立)을 위한 기초자료(基礎資料)로 활용(活用)하고자 실험(實驗)한 결과(結果)를 요약(要約)하면 다음과 같다. 1. $GA_3$ 함양(含量)은 개화전기(開花前期)에 4.87mg/kg으로 가장 높은 수치(數値)를 보였으며 이 시기(時期)를 중심(中心)으로 하여 전(前) . 후단계(後段階)로 갈수록 감소(減少)하는 경향(傾向)이었다. 2. IAA의 함양(含量)도 개화전기(開花前期)에 2.27mg/kg으로 가장 높은 경향(傾向)이었고 그 전(前) . 후단계(後段階)로 갈수록 0. 15 -0.33mg /kg 수준(水準)으로 감소(滅少)하였다. 3. ABA는 생육단계(生育段階)가 진전(進展)됨에 따라 점진적(漸進的)으로 증가(增加)하여 결실기(結實期)에 0.37mg/kg으로 가장 높았다. 그리고 개화기(開花期)에는 일시적(一時的)으로 감소현상(減少現像)을 보였다.

• 한국작물학회지
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• 제65권1호
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• pp.22-29
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• 2020

Rice is very sensitive to high temperatures during the reproductive stage, particularly during the flowering and anthesis periods. To determine how high temperatures result in sterility during the flowering period in Korean rice cultivars, groups of 11 cultivars were subjected to different temperature regimes (24, 28, 30, and 33℃) during the flowering stage using sunlit phytotrons. At an average of 33℃, all 11 rice cultivars reached anthesis earlier than at the other temperatures. Microscopy analyses revealed significant differences in pollen germination and pollen viability in cultivars grown at 33℃ compared to those cultured at lower temperatures. At 33℃, the cultivars had significantly lower fertility rates (47% reduction) than cultivars grown at 24℃. These findings are important as rice pollination and fertility depend on the pollen viability and germination. The present study shows that rice fertility is negatively affected by excessively high temperatures.

• 한국식생활문화학회지
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• 제19권6호
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• pp.598-604
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• 2004

This was aim to study the changes of components by different parts and maturity of tomato. We found that orally fed tomatine which induced a significant reduction in cholesterol in hamster in contrast to potato glycoalkaloids, the safety of tomatine was supported by our observation that pickled green tomatoes consumed widely in many countries has a high tomatine content. The tomatoes harvested during the first stage(10 days after flowering) contained tomatine $6333.49{\mu}g\;per\;100g$ and dohydrotomatine and ${\alpha}$-tomatine in a ratio of about 1:13.8. The tomatine content then decreased by about 85% during stage 2(20 days after flowering) an dehydrotomatine contene dropped to a value near zero during stage 3, 4 It on the tomatine content dropped to a value near zero during the final stage(50 days after flowering). With respect to health benefits at all stages of maturity, unripe tomato contain chlorophyll and ${\alpha}$-tomatine should consumed.

• 원예과학기술지
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• 제19권2호
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• pp.163-169
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• 2001

본 실험은 오리엔탈 나리 'Casa Blanca'의 유용한 향기성분을 찾아내어 이 성분들의 개화단계별 정유함량과 정유성분 구성의 차이를 알아보고 각각의 이용 가능한 추출적기를 규명하고자 수행하였다. 'Casa Blanca'의 개화단계별 정유함량은 꽃봉오리 단계를 제외하고는 개화단계가 진행됨에 따라 증가하여 만개 후 개화 단계에서 가장 높았다. 오리엔탈 나리 'Casa Blanca'의 정유성분을 분석해 본 결과 이들의 주성분은 각 단계에 따라 farnesol(18.96%), benzyl salicylate(13.81%), butyl-hydroxy toluene(12.87%), geranyl linalool isomer(7.46%), isoeugenol(7.17%)이었다. 이들의 개화 단계별 정유성분을 비교해 보면, fatty acid derivative류는 개화 초기와 개화 후기에 많은 반면 benzenoid류는 개화 중기, 만개 단계에서 많았다. 오리엔탈 나리 'Casa Blanca'의 주성분 중 butyl-hydroxy tolune과 isoeugenol과 같은 benzenoid류 물질들은 대부분 강한 항산화 효과가 있어 식품의 첨가제나 방부제로 이용 가능할 것으로 기대된다. Geranyl linalool isomer와 같은 monoterpene계 물질은 개화 후기로 갈수록 함량이 증가되었고 나리의 구성 성분 중 가장 많은 함량을 나타내는 farnesol과 같은 sesquiterpene계 물질은 만개 시에만 나타났고 이는 geranyl linalool isomer와 함께 좋은 향기를 가져 중요한 향료로 이용 가능할 것으로 기대된다. 이러한 오리엔탈 나리 'Casa Blanca'의 유용한 주성분들의 개화단계에 따른 추출적기를 살펴보면 farnesol, benzyl salicylate은 만개단계, butyl-hydroxy tolune은 1/2 개화한 단계, geranyl linalool isomer, isoeugenol는 만개 후 단계였다. 이로 미루어 보아 오리엔탈 나리 'Casa Blanca'의 정유는 개화단계에 따라 정유성분과 정유함량에 변화가 있었으며, 이들 성분은 추출적기를 알맞게 고려한다면 향장류나 식품첨가제, 아로마테라피 등에 유용하게 이용될 것으로 기대된다.

• 원예과학기술지
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• 제30권3호
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• pp.236-242
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• 2012

We investigated the influences of night interruption (NI) and night temperature on flowering and flower coloration in Cymbidium. Cymbidium 'Red Fire' and 'Yokihi' were grown under a 9 hours photoperiod (control), a 9 hours photoperiod with NI at a low light intensity (LNI) of 3-7 ${\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$, or a 9 hours photoperiod with NI at a high light intensity (HNI) of 120 ${\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ for four hours (22:00-02:00 HR) for 16 weeks during the reproductive growth stage (Experiment 1). Thirty month-old Cymbidium 'Red Fire' plants with initiated flowering buds were placed in four different growth chamber with night temperature set points of 6, 9, 12, or $15^{\circ}C$ for 16 hours (18:00 to 09:00 HR) and a daytime temperature of $25^{\circ}C$ (Experiment 2). In Experiment 1, the numbers of visible buds and flowers increased, and time to flowering decreased in both the LNI and HNI treatments, as compared to the control in both cultivars. Red color in Cymbidium 'Red Fire' increased by both LNI and HNI, as evidenced by an increased $a^*$ in plants grown under these conditions, relative to those grown under the control condition. Number of days to visible buds at 9-$15^{\circ}C$ ranged from 31-34 days, as compared to 39 days at $6^{\circ}C$ in Experiment 2. Although as the temperature increased days to flowering decreased when the plant was grown at $15^{\circ}C$ as compared to 6, 9, or $12^{\circ}C$, the red color ($a^*$) also decreased. The number of flowers and percent flowering increased when the night temperature was maintained higher than $9^{\circ}C$. Therefore, NI treatment and maintaining the night temperature at approximately 9-$12^{\circ}C$ during the winter season after flower spike initiation in the reproductive developmental growth stage improve flower quality and controls flowering time.