• 환경생물
• /
• 제37권4호
• /
• pp.682-689
• /
• 2019

이 연구에서는 주요 가로수인 왕벚나무를 대상으로 구례지역의 조기낙엽 현황 진단을 위해 제주도와 낙엽비율 비교연구를 진행하였고, 구례군에서 수행가능한 주요 가로수 관리방법을 두 가지로 구분하여 관리방법별 조기낙엽 지연효과와 피해를 규명하여 최적관리방법을 도출하였다. 구례지역은 기상청 단풍시기와 낙엽시기가 유사한 제주도 지역보다 같은 시기 낙엽비율이 높았고, 약제처리, 약제와 관수처리를 진행했을 때 구멍병이 방제되어 낙엽 시기가 2주 지연되었다. 조기낙엽은 왕벚나무의 생장과 개화에 영향을 미쳤으며, 약제와 관수처리를 진행한 관리방법에서 생장이 가장 높았고, 2년 뒤 개화량이 가장 높은 것으로 추정되었다. 따라서 왕벚나무 가로수의 조기낙엽을 지연시키기 위해 구멍병 방제가 중요하고, 조기낙엽이 수관의 발달과 개화량에 영향을 미칠 수 있으므로 약제와 관수처리를 함께 처리하는 관리방법을 도입하는 것이 필요할 것으로 생각된다.

• 한국작물학회지
• /
• 제2권
• /
• pp.50-56
• /
• 1964

(1) 양마의 개화 및 수정현상을 조사해서 교잡육종에 참고자료를 얻고저 이 실험을 하였다. (2) 양마의 개화시각은 품종에 따라서 현저한 차이가 있으며 따른 것은 오후 11시부터 11시 30분 늦은 것은 오전 9시 30분부터 10시 사이에 개화를 끝냈다. 가장 개화가 빠른 품종은 한국재래종이고 (P.M. 12∼12시 30분, 성화기) 제일 늦은 품종은 미국에서 도입한 Everglades 71(AM6∼6시 30분, 성화기)이며 Guatemala에서 도입한 Guatemala 38F(A.M. 4∼4시 30분, 성화기), Guatemala 2A(A.M. 4시 30분∼5시, 성화기) 미국종과 한국종의 중간정도로 개화하였다. (3) 한국재래종에 있어서는 동일품종에 있어서도 개화초기와 개화종기에 있어서는 개화시각이 다소 상이하였고 후자의 개화시각은 전자보다 늦었다. 이 원인은 주로 기온에 영향되는 것 같았고 온도의 저하에 따라 개화시각도 늦어지는 것 같이 생각되었다. (4) 상마는 개화됨과 동시에 수술의 화사가 신장되고 개약하여 수분이 되며 수분하여 수정이 되는 소요시간은 5∼6시간으로 볼 수 있었다. (5) 품종간 교잡에 있어서 제일 알맞은 교배시각은 각 품종의 개화최성기라고 생각되었다.

• The Korean Journal of Ecology
• /
• 제1권1호
• /
• pp.17-23
• /
• 1977

Flowering dates of 389 plant species in the Hongneung Arboretum, Seoul, had been recorded from 1968 through 1975. The thermal analysis on the air temperature as the key factor determining the first flowering date, with climatological data obtained in the Arboretum, were undertaken by Nuttonson's Index (1948) and Lindsey & Newman's Index (1956). The results and conclusion in this study are as follow; Peak in the bell shape distribution curve of the species and first flowering dates, largely, was early May. Flower spans of most species were 10 to 20 days, neverthless, some species flower only a few days while others may stay flowering a hundred days even more. Increase-curves of summation temperature from early spring through late-summer showed almost the same mode in both Nuttonson;s Index (Tn) and Lindsey & Newman's Index (T1). These Indices manifested the exponential curve, increasing slowly at the beginning of spring chiefly but rapidly from the middle part of April. The equation of the linear relationahip between Tn and Tl as far as in thisstudy is as follow. Tl=230Tn It appears that the distribution of summation temperature, below Tn=400°C·day, affects the first flowering, even though it could be modified somehow by the distribution of precipitation, day length and others. Nuttonson's Index (Tn.f) and Lindsey & Newman's Index (Tl.f) upon the thermal amount first flowering dates have been respectively simulated as follow. Tn.f=θa + C Tl.f=230θa + 230C where θ is air temperature 10°C, a and C are a constant.

• Molecules and Cells
• /
• 제42권5호
• /
• pp.406-417
• /
• 2019

RICE FLOWERING LOCUS T 1 (RFT1) is a major florigen that functions to induce reproductive development in the shoot apical meristem (SAM). To further our study of RFT1, we overexpressed the gene and examined the expression patterns of major regulatory genes during floral transition and inflorescence development. Overexpression induced extremely early flowering in the transgenics, and a majority of those calli directly formed spikelets with a few spikelets, thus bypassing normal vegetative development. FRUITFULL (FUL)-clade genes OsMADS14, OsMADS15, and OsMADS18 were highly induced in the RFT1-expressing meristems. OsMADS34 was also induced in the meristems. This indicated that RFT1 promotes the expression of major regulatory genes that are important for inflorescence development. RFT1 overexpression also induced SEPALLATA (SEP)-clade genes OsMADS1, OsMADS5, and OsMADS7 in the greening calli before floral transition occurred. This suggested their possible roles at the early reproductive stages. We found it interesting that expression of OsFD1 as well as OsFD2 and OsFD3 was strongly increased in the RFT1-expressing calli and spikelets. At a low frequency, those calli produced plants with a few leaves that generated a panicle with a small number of spikelets. In the transgenic leaves, the FUL-clade genes and OsMADS34 were induced, but SEP-clade gene expression was not increased. This indicated that OsMADS14, OsMADS15, OsMADS18, and OsMADS34 act immediately downstream of RFT1.

• 한국작물학회지
• /
• 제7권1호
• /
• pp.129-132
• /
• 1969

The polygenic variation in flowering time of soybean irradiated with Co$^{60}$ gamma ray evaluated in the R$_2$ generation. The genetic variance in the irradiation treatment was about four times that of the control. The basic possibility of selection for the early and the late in flowering time of soybean after irradiated with Co$^{60}$ was suggested in this paper.

• 한국작물학회:학술대회논문집
• /
• 한국작물학회 2022년도 추계학술대회
• /
• pp.285-285
• /
• 2022

Recent unpredictable climate change is a major cause of rice yield loss. In particular, methane is a key factor in global warming. Therefore rice breeders are trying to breed the reducing-methane gas emission rice using the crossbreeding method. However, the traditional crossbreeding method takes 8 to 10 years to breed a cultivar, and the anther culture method developed to shorten the breeding cycle also takes 6 to 7 years. On the other hand, CRISPR/Cas9 accurately edits the target trait and can rapidly breed rice cultivars by editing the target trait as a homozygous in 2-3 years. In addition, exogenous genetic elements such as Cas9 can be isolated from the G₁ generation. Therefore, the flowering time was regulated by applying CRISPR/Cas9 technology, and OsCKq1 genome-editing (OsCKq1-G) rice with early flowered and high yield was bred in the field. Genome-editing of OsCKq1 applied CRISPR/Cas9 technology up-regulates the expression of the flowering promotion gene Ehd1 under long-day conditions induces early flowering and increases the yield by increasing the 1,000-grain weight. And as the generations advanced, each agricultural trait indicated a low coefficient of variation. As a result, indicated that OsCKq1 plays an important role in regulating the flowering time and is related to the trait determining yield. Therefore, OsCKq1-G can suggest a breeding strategy for the Net-Zero national policy for reducing-methane gas emission rice by shortening the breeding cycle with the early flowered, and high-yield rice. CRISPR/Cas9 technology is a rapid and accurate breeding technology for breeding rice cultivars with important characteristics.

• 한국자원식물학회지
• /
• 제28권1호
• /
• pp.111-118
• /
• 2015

유채의 경관효과를 높이기 위해 국내 육성 및 국외 도입 유채 8품종을 봄철에 파종시기를 달리하여 파종하고 품종, 파종시기 및 재배지역에 따른 생육 및 개화특성을 구명하여 봄 파종에 적합한 유채품종 및 파종시기를 구명한 결과, 파종시기가 늦어짐에 따라 유묘 출현소요일수는 짧아졌고, 초장 및 착화수는 감소하였으며 분지수는 증가하였다. 무안과 제주 포장 모두에서 파종일이 늦어짐에 따라 개화시는 지연되었고 개화지속일은 감소하였다. 개화소요일수는 파종이 늦어짐에 따라 단축되었는데, 3월 1일 파종 시 73~94일이 소요되었으며, 3월 31일 파종 시 57~71일로 짧아졌다. 조생종인 '탐미유채'와 '목포 111호'가 만생종인 '탐라유채'와 '내한유채'보다 모든 파종시기에서 10일 정도 빠르게 개화하였다. 개화지속기간도 파종시기가 늦어짐에 따라 5~14일 정도 단축되었다. 경관용 유채 봄 파종 시 파종시기가 빠를수록 개화특성이 향상되었고, 국내육성 품종으로는 조기개화종인 '탐미유채'와 독일도입종인 '봄유채'가 봄 파종에 적합한 품종으로 나타났다.

• 한국작물학회지
• /
• 제51권2호
• /
• pp.113-117
• /
• 2006

To identity the effect of sowing dates on flowering and maturity of sesame, some agronomic traits including days to flowering and days to maturity were investigated under five different sowing dates. Plant height, days to flowering, days to maturity, days from flowering to maturity and number of capsules per plant were showed significantly different by years, sowing dates and varieties. Interaction between sowing dates and varieties affected to days to flowering, days to maturity, days from flowering to maturity and number of capsules per plant. Plant height, days to flowering and days to maturity decreased significantly as sowing dates were delayed, but number of capsules and seed weight per plant showed highest at the sowing date of May 10. At the regression analysis of shortness degree of growth period by the response of days to flowering and days to maturity under different sowing dates, sesame varieties with earlier flowering habit were much less affected by day length rather than ones with later flowering habit. $R^2$ and gradient value on the days to maturity regression graph were smaller indicating that maturity was much less sensitivity than flowering to the change of day length and temperature in the move of sowing dates. Therefore, it would be concluded that early maturity sesame varieties have higher potential adaptability to various sesame cropping systems in view of their less sensitivity to day length changes under different sowing dates.

• Journal of Plant Biology
• /
• 제19권1호
• /
• pp.14-18
• /
• 1976

Inhibition of flowering in Lemna perpusilla 6746 by 30 mM sucrose was reversed by the addition of acetylcholine (>$10^{-4}M) supplemented with 10^{-4}M$ ascorbic acid to 1/10-strength Hunter's growth medium. The reversible effect of acetylcholine was found to be greater at early stages of flowering than in the later period. Promotive effects of both acetylcholine ($10^{-3}M) and eserine(10^{-5}M$) on flowering in the short-day plant under various photoperiodic conditions were studied. It was indicated that the application decreased length of the critical dark period for the floral induction, and it was also shown that the endogenous status of acetylcholine was involved in the floral response which had a correlation with phytochrome. Interruption of inductive dark periods by red irradiation (1min) immediately followed by far-red light (1 min) completely inhibited flowering, while the addition of acetylcholine and eserine to the medium under the same condition slightly promoted flowering, indicating possible involvement of phytochrome system in acetylcholine activity for photoperiodic sensitivity of floral response in Lemna perpusilla 6746.

• Journal of Plant Biotechnology
• /
• 제1권2호
• /
• pp.109-115
• /
• 1999

A linkage map of Capsicum annuum L. was constructed by random amplified polymorphic DNA (RAPD) markers followed in a backcross population of an intraspecific cross between cultivars HDA210 and Yatsufusa. A total of 420 random primers were tested and 311 polymorphic bands were generated by 158 random primers. Among them, 86 Yatsufusa specific bands generated by 52 primers were examined for mapping. Most bands except three segregated in Mendelian fashion fitting the expected 1:1 ratio. The total length of the map was 533 cM distributed in 15 linkage groups. The map distance between adjacent markers ranged 0 to 32.8 cM, with an average distance of 9.1 cM (63 markers). Some markers were clustered and this may be due to the amplification of a repetitive sequence by the RAPDs. Primer pairs for a sequence characterized amplified region (SCAR) were developed and the segregation scores by the SCAR primers were in accordance with the RAPD data. Two QTL markers for number of axillary shoots and for early flowering were developed. One QTL for early flowering located in the linkage group 3 and explained 61 "io of the phenotypic variation. The other QTL for the number of axillary shoots located in the linkage group 4 explained 55 % of the phenotypic variation.tion.