• KOREAN JOURNAL OF CROP SCIENCE
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• v.47 no.6
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• pp.437-442
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• 2002

To breed high quality and yield peanut variety according to select the short flowering duration, fifteen germplasms (1 virginia,7 spanish,6 valencia types and var, Daekwang) were investigated the flowering habit and agronomic characteristics from 1998 to 1999. Emergence date of the selected short flowering duration germplasms (SPFGs) was earlier 1-3 days and middle or small seed than that of var, Daekwang. Main stem length was longer 57cm but the number of branches, pods, 100-seed weight, and pod weight per plant was reduced 25%, 23%, 42%, 46%, respectively, in SPFCs comparing to var, Daekwang. The flowering date in SPFGs was similar but the flowering duration was earlier 5-16 days than that of var, Daekwang (52 days). Varieties that flowered shorter duration than 50 days were 18.8% among the SPFGs. The number of total flowers in SPFGs was fewer 50% than that of var, Daekwang. The rate of flowering inhibition were 50-52% than that of var Daekwang. The frequencies of flowering duration (under 50 days) were 7.7% in virginia, 46.2% in spanish, 53.9% in valencia. The effect of shading treatment on rate of flowering inhibition were 11%, but number of branches and pods were reduced by 27-31% in valencia type compared to non-shade. Correlation coefficient was significant positively ($r=0.9314^*$ virginia, $r=0.9551^*$ spanish, $r=0.9551^*$ valencia) between the air temperature and flower number, The frequency of peg and pod number on 1st to 2nd nodes in SPFGs were more 3-12%, 21-26% than that of var. Daekwang. The rate of mature pods at 80 days after flowering were higher 12-17% than that of var, Daekwang (68%). Correlation coefficient was high significant negatively between date of first flower and flowering date, the ratio of mature pod.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.14
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• pp.133-137
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• 1973

In order to classify the ecotypical and maturing groups 136 Korean local and 4 Japanese Perilla varieties were sown at Suwon on May 20, 1972, and investigations were made on days to flowering, days to maturing and growth duration. Results obtained were summarized as follows: 1. Ecotype was classified from 6 groups with combination of the long and short duration from sowing to flowering and maturing period. The classified symbols of groups were Ia, Ib, IIa, IIIa, and IIIb. I: long duration. to flowering II: medium duration to flowering III: short duration to flowering a: long duration to maturing b: short duration to maturing Korean local varieties were distributed 3 ecotypes of IIa, IIb and IIIa, however, Japanese varieties did 2 ecotypes of IIa and IIb, respectively. 2. Maturing group was classified from 3 groups with long (I), medium (II), and short (III) growth durations. Korean local varieties belong to II and III groups but Japanese varieties belong to I and II groups, respectively. 3. Three were highly significant positive correlation (0.685) between ecotypical and maturing group. Ecotype was more related with days to flowering and growth duration, however, maturing group was related with days to flowering, days for maturing, and growth duration. Korean local varieties, more distributed into ecotype than maturing group, were attributed to differences of environmental conditions and cultural practices at different provinces.

• Journal of Ecology and Environment
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• v.42 no.2
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• pp.50-59
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• 2018

Background: Duodichogamy is the rarest form of dichogamy in angiosperms, which is characterized by flowering in the sequence of male${\rightarrow}$female${\rightarrow}$male. Disentangling factors promoting duodichogamy require the discovery of more duodichogamous species in angiosperms. However, extremely limited information on duodichogamous species makes it difficult to make general conclusions. Given the inflorescence morphology and flowering characteristics, the Meliaceae family is highly likely to contain duodichogamous species. Methods: We selected 48 individuals from 20 populations in Korea and investigated their flower morphology, arrangement of flowers by sexual condition within inflorescences, and flowering phases and duration of male and female flowers of Toona sinensis (Meliaceae) for 5 years (2011-2015) to determine if the species shows duodichogamous flowering. Results: Toona sinensis belonging to Meliaceae possessed functionally unisexual flowers with rudimentary parts of the opposite sex. The floral organs in male were larger than those in female, except for ovary length and width. In dichasium, male flowers were observed on primary or lateral branches, whereas female flowers were borne only on lateral branches. Overall, individuals from six different populations flowered in the male${\rightarrow}$female${\rightarrow}$male sequence, thereby male is blooming far longer than female flowers at the level of individual trees (male vs. female = 17-20 days vs. 2-4 days). Conclusions: This is the first study to report a duodichogamously flowering species, T. sinensis, within Meliaceae. Several flowering characteristics observed from T. sinensis may be important clues used to discover additional duodichogamous Meliaceae species. Short flowering period and relatively small number of female flowers, which is analogous to reduced ovule numbers observed in other duodichogamous species, may intensify male-male competition in T. sinensis. This study contributed to narrowing down potential candidates of duodichogamy based on their geographic distributions and flowering time.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.27 no.2
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• pp.99-106
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• 1982

Highly positive correlations were obtained between the growth duration of the 1978 IReTN entries in Chuncheon, Korea and all the experimental sites in 7 other countries. Among the entries the photoperiod responsive varieties had very long growth duration in Chuncheon although relatively early in flowering in the other low latitude sites. Selection under Korean conditions would eliminate the short growth duration varieties caused by photoperiod sensitivity in tropics or sub tropics. Except for photoperiod sensitive rices, selection of varieties or lines for optimum growth duration before further evaluation in other low temperature areas would be most effective in Chuncheon, Korea.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.5 no.1
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• pp.45-49
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• 1969

The photoperiod and temperature response of Korean varieties were studied under field and greenhouse conditions. Results of the experiment indicated that all varieties tested were relatively intensitive to photoperiod. The early varieties were least affected by photoperiod while the late varieties showed the greatest response. Low temperature delays flowering either under short daylength or natural daylength. In general, temperature has a greater effect than photoperiod on the growth duration of the varieties used. The late varties had longer photoperiod-sensitive phase than the early varieties. Temperature has very little effect on the photoperiod-sensitive phase. The basic vegetative phase is longer in the early varieties than the late varieties. High temperature results shorten duration of the basic vegetative phase.

• Korean Journal of Medicinal Crop Science
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• v.9 no.3
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• pp.186-191
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• 2001

This study was conducted to find the flowering and seed setting characteristics of Eleutherococcus spp. Plants of Eleutherococcus spp. were 7 years old trees reproducted by cutting method using seven species in Gongju. Initial flowering date was foremost by May 9 in E. sieboldianus and hindmost by August 23 in E. divaricatus among seven species. Flowering duration was most short by 20 days in E. sieboldianus and extremely long by 42 days in E. sieboldianus. Number of flowers per plant in E. sieboldianus and E. chilsanensis were higher by 4677 and 4634 than those in E. divaricatus and E. sieboldianus by 780, 84, respectively. The fruit setting percent was the highest in E. sieboldianus by 95% and numbers of fruit setting per cluster showed the highest value by 153 in E. sieboldianus. The seed setting percent was almost same by ${92{\sim}95%}$ in E. sessiliflorus, E. chiisanensis, E. koreanus, E. divaricatus and E. seoulensis, but lower by ${11{\sim}37%}$ in E. senticosus and E. sieboldianus. The dry weight per plant and 100-fruit weight showed the highest value by 270g, 6.7g in E. sessiliflorus, respectively.

• Korean Journal of Agricultural Science
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• v.4 no.1
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• pp.51-60
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• 1977

In order to determine ecological variations of flowering date and yields under the different seasonal cultures, and to select the higher yielding varieties which were adaptable to Korean climate, 100 mungbean cultivars were sown at the interval of 15 days from April 22 to July 21 in 1976. The results obtained are summarized as follows: 1. The number of days required to flowering from seeding were decreased by delaying the seeding date. 2. When accumulated temperature at first flowering from seeding were reached $945-1,126^{\circ}C$, the mungbean cultivars started to flower regardless of seeding dates. Especially, when mungbean was planted around standard planting date, the plants flowered for very short duration. 3. There were highly significant correlations between the number of days from seeding to flowering at each seeding date and standard planting date. 4. Yields per plant were tend to decrease with the delay of seeding date but there were no significant difference between seeding dates. Therefore, it appears that mungbean can be planted for longer period of time compared to other crops such as rice and soybean. 5. Highly significant correlations were found between the number of days of first flowering and yields per plant at most seeding dates. 6. It may be feasible to grow high yielding mungbean cultivars such as CES 140, LM 2100, LM 690, L 576 and LM 689 after harvesting of spring vegetables in May and before planting of fall vegetables.

• Journal of agriculture & life science
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• v.53 no.4
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• pp.19-28
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• 2019

This study was conducted to investigate the effect of nutrient solution strength and duration of nutrient starvation on the growth and development of strawberry (Fragaria x ananassa Duch.) 'Maehyang' and 'Sulhyang' at the flowering stage. Cuttings of runner plants were stuck on November 23th, 2017 and were covered with a layer of black plastic film to block light from penetrating and keep the relative humidity high. The black plastic film was removed after 16 days and rooted plants were cultivated for one month with irrigation of water. The Yamazaki nutrient solution with an electrical conductivity (EC) of 1.85 or 3.71 dS·m-1 (1x or 2x ionic strength, respectively) and pH 5.55 was fed to plants after either 0 (control), 1, 3 or 5 weeks of nutrient starvation to the end of experiment. Plant height in both cultivars decreased gradually with the increase in duration of nutritional starvation. The earlier the nutritional starvation started, the smaller the shoot fresh weight of 'Maehyang'. Hence the greatest shoot fresh weight was obtained in the control which was supplied with the nutrient solution continuously. Shoot fresh weight of 'Sulhyang' was the greatest in 1x ionic strength and one week of nutrient starvation before planting. Although number of flowers on the first flower cluster of 'Maehyang' and 'Sulhyang' showed no significant differences, 'Maehyang' had the greatest number of flowers in the 2x ionic strength solution and one week of nutrient starvation before planting, while 'Sulhyang' had that in the 1x ionic strength treatment. These results suggest that it is considered effective to supply a nutrient solution at a low concentration for a short period of time for increasing the number of flower differentiated on the first flower cluster in both cultivars.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.32 no.4
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• pp.409-416
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• 1987

The object of this study was to investigate the differences in dry matter production, physiological characteristic and grain yield of soybean (Glycine max (L.) Merr.) as affected by planting dates in southern region of Korea. This experiment was conducted using four planting dates and four varieties over 3 years (1982-1984). The different responses of soybean varieties to different temperature and daylength, days from planting to flowering were ranged from 43 to 55 days when planted on May 10 long daylength and low temperature condition. Flowering duration was ranged from 12 to 27 days and 9 to 13 days for the plantings made on May 10 and July 9, respectively. Therefore, it was the shortest under the short daylength and high tempera-ture condition. It also appeared that the later planting caused the lower dry matter weight and leaf area index which resulted in lower grain yield. But grain yield was not directly correlated with the unbalance of Xink/Source Ratio and the lodging from excessive vegatative growth. The grain yield was the highest in May 30 and the lowest in July 9 planting: it was ranged from 2.26 to 2.55 t/ha in the former and 0.85 to 1.20 t/ha in the latter, respectively. The increase in yield was depended on the increase in the number of pods per plant, the number of seeds per pod and the seed weight. The distribution ratio of dry matter to leaves was the hightest at the sixth trifoliolate leaf stage and gradually declined thereafter in all planting dates, and it also appeared that the later planting, the lower the ratio of dry matter to leaves.

• Korean Journal of Agricultural Science
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• v.25 no.1
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• pp.6-11
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• 1998

Bean sprout is one of the traditional vegetable in Korea and produced by sprouting soybean (Glycine max L.) cultivars. This experiments was conducted to investigate the ecological characteristics in collected small grain soybean lines from Chungnam province region. Thirty varieties were used in this study. Seed coat color of collected small soybean lines showed eight different types. Major seed coat color type was yellow as 8 lines of total 35 lines. The stem height, number of nodes and number of branches averaged 58.5 cm, 16.5 nodes and 11.8 branches, respectively. The average number of main stem pods and number of branching pod were appeared 43.1 and 62.7 respectively. One hundred seed weight averaged 9.9g which was lower than 10~12g of sprouting soybean cultivars as breeding goal of Korea. The average of node width showed 13.2cm and long stem open types and short stem close types were classified 1 line and 14 lines. The flower dates of collecting small soybean lines were between 8 Aug. and 13 Aug. and flowering duration was 74~85 days. The date of maturity were between 12 Sep. and 12 Oct., and maturity duration showed great variation among cultivated soybean lines.