• Horticultural Science & Technology
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• v.33 no.6
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• pp.807-811
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• 2015

This study was conducted to identify the air temperature factors that affect leafing date of mulberry (Morus alba) in Buan, Jeonbuk province. Over the period from 2009 to 2014, the leafing date averaged April 24 (114 Julian days). The earliest leafing date was April 12, in 2014, and the latest leafing date was May 2, in 2011. Yearly variations of daily mean temperature (DMT) and daily maximum temperature (DMxT) were high in the last part of March. There were highly negative correlations between leafing date and degree days of accumulated DMT above 0, 5, and $10^{\circ}C$ in the period from March 1 to April 10. Linear regression equations for estimating the leafing date were y = 153.8 - 0.1886 ${\times}$ ($r^2=0.965^{**}$) and y = 126.2 - 0.2246 ${\times}$ ($r^2=0.825^*$) for the degree days of accumulated DMT above $5^{\circ}C$ in the period from March 1 to April 10 and the last part of March, respectively. Therefore, leafing date of mulberry, which is important for popcorn disease control, is 96.5% predicted by degree days of accumulated DMT above $5^{\circ}C$ in the periods from March 1 to April 10.

• The Korean Journal of Ecology
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• v.8 no.1
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• pp.53-59
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• 1985

Phenological development, flowering and leafin times of Rhododendron muronulatum and R. schlippenbachii along elevagtion were studied at Mt. Kwanak, 629m high above the sea level, in Seoul. Flowering and leafing time of the former were delayed at the rate of 2.3~3.3 days and those of the latter were of 2.0~3.0 days per 100m ascent. Phenological changes of both plant species were closely correlated with minimum air temperature first, and then soil water content and minimum soil temperature among the climatic factors. Phenological difference caused by altitude and slope direction(southeast-northwest) among the topographic factors was admitted at the high significance level, but the difference by ridgevalley was little.

• Journal of Bio-Environment Control
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• v.19 no.3
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• pp.165-170
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• 2010

This experiment was conducted to select the affected main factors on growth and fruit characteristics of 'Fuyu' persimmon (Diospyros kaki Thunb.) in 25 factors of air temperature factors in Naju. Mean air temperature, cumulative temperature and days for March and April of 25 factors were the highest annual variation. Number of the first and second principal components extracted from 25 air temperature factors were 14 and 3 factors related with mean temperature for annul and April, and cumulative contribution of these was 52.2%. Also the affected years by the first principal components were 1990, 1980 and 1986. Annual standard deviation on leafing, flowering and maturing date were 4.0~6.7 days range, and flowering date and days from leafing to flowering had the highest coefficient of variation. Annual variation of days from flowering to maturing date was affected by greatly mean air temperature and days of cumulative temperature in October, days from March 1 to leafing date was affected by cumulative temperature for growing period, days from leafing to flowering date was affected by mean air temperature in April. Annual variation of fruit weight was affected by mean air temperature for March and October.

• Proceedings of the Korean Society of Crop Science Conference
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• 1987.06a
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• pp.30-31
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• 1987

• Proceedings of The Korean Society of Agricultural and Forest Meteorology Conference
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• 2005.09a
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• pp.147-147
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• 2005

• Korean Journal of Plant Resources
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• v.24 no.5
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• pp.549-556
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• 2011

We investigated the plant phenology on the threatened species for climate change in the summit area of Mt. Deogyusan which is a representative sub-alpine zone in Korea. We had performed the monitoring survey of plant phenology on 38 species including 20 trees and 18 herbs from May 2009 to November 2010. The investigated phenological charateristics were five dates for leafing, flowering, floral abscission, autumn leaf colors and leaf abscission on each plant species in sub-alpine region. The climate data were measured from November 2009 to December 2010. The range of temperature was from 30.4 to -$20.3^{\circ}C$ at Hyangjeokbong to Jungbong region, and the relative humidity was 100% to 3.4%. The leafing dates in 2010 were similar to 2009 or were 6-20 days delayed in most of the investigated species except Veratrum oxysepalum and Sanguisorba hakusanensis which showed 8 days earlier leafing dates in 2010. The biggest difference among phenological characters was found in flowering dates. The flowering dates of early Spring blooming species such as Heloniopsis koreana, Rhododendron yedoense for. poukhanense and Viola orientalis showed 13-20 days earlier in 2010, and the several summer flowering species as Viburnum opulus var. calvescens, Smilacina japonica and Bupleurum longeradiatum showed 6-10 days delay in 2010. The dates for floral abscission and autumn leaf colors in 2010 were delayed about 10-18 days, and leaf abscission dates were similar to 2009. The effects of climate change on the phenology for the threatened species in sub-alpine zones of Korea are occuring especially on flowering, floral abscission and autumn leaf colors.

• Korean Journal of Environment and Ecology
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• v.22 no.3
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• pp.221-229
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• 2008

This study observed and compared phenological changes in the spring for some native woody plants growing at Mt. Jumbong and Mt. Bongeui located at central districts of our country, and also inquired into the phenological difference subsequent to microclimate change by measuring its related environment factors as well. The average air temperature at a survey point of Mt. Jumbong from January to May in 2004 was $4.1^{\circ}C$ lower than that of Mt. Bongeui. As for the soil temperature in April by a survey section within Mt. Jumbong, the soil temperature on the west and northwest slopes was $1.8^{\circ}C$ and $4.4^{\circ}C$ lower than that of the south slope, respectively. It was found that the earliest tree species in a flowering period was Lindera obtusiloba among the sample woody plants and its flowering began in late March at Mt. Bongeui and in early April at Mt. Jumbong. The flowering of the same species began faster on the south slope than the west or north slope; in case of the tree species flowering in early spring, there appeared about two-week interval between the survey sites. Likewise, leafing time of the same species was two weeks earlier at Mt. Bongeui(in mid-April) than at Mt. Jumbong(in early May). Nuttonson's Index and Year Day Index for the flowering and leafing time of the same species showed similar value between the survey sites. It is analyzed that the transition in phenological phases between the sites is mainly caused by temperatures; further, it is implied that the climate changes and rise in temperatures could expedite the changes in phenological phases more than ever.

• Korean Journal of Food Science and Technology
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• v.44 no.6
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• pp.772-778
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• 2012

This study was conducted to investigate physiologically active components and antioxidant capacity of grapevine leaves at growth stages. The leaves from two strains of grapevine, 'Campbell Early' and 'Rosario Bianco', were collected at five different growth stages (leafing, blossom, fruiting, coloring, and maturity). Total flavonoid content was higher in leafing stage than the other stages and gradually decreased during growing. Total phenol content was higher in 'Campbell Early' than in 'Rosario Bianco'. Hydroxyl radical scavenging ability increased in the leafing stage and decreased during growing. The electron donating ability was higher in 'Campbell Early' then 'Rosario Bianco' until blossom stage. Leaves from 'Campbell Early' showed higher total antioxidant capacity than those from 'Rosario Bianco'. According to the above results, grapevine leaves until the blossom stage would possess strong antioxidant activity by physiologically active components such as polyphenol compounds. Therefore, these results suggest that young grapevine leaves can be used as materials for the development of functional foods.

• Journal of Ecology and Environment
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• v.30 no.2
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• pp.143-149
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• 2007

To certify predictability for the times of phenological stages from cumulative air temperature in springtime, the first times of budding, leafing, flower budding, flowering and deflowering for 14 woody plants were monitored and air temperature was measured from 2005 to 2006 at Namsan. Year day index (YDI) and Nuttonson's Index (Tn) were calculated from daily mean air temperature. Of the 14 woody species, mean coefficient of variation was 0.04 in Robinia pseudo-acacia and 0.09 in Alnus hirsuta. However, mean coefficient of variation was 0.30 in Forsythia koreana and Stephanandra incisa and 0.32 in Zanthoxylum schinifolium. Therefore, the times of each phenological stage could be predicted in the former two species but not in latter three species by two indices. Of the five phenological stages, mean coefficient of variation was the smallest at deflowering time and the largest at budding time. In five phenological stages, mean coefficient of variation of YDI was in the range of $0.11{\sim}0.21$ but that of Tn was in the range of $0.15{\sim}0.26$. Therefore, the former was a better index than the latter. Of the species-phenological stage pair, coefficient of variation of YDI was 0.01 in Acer pseudo-sieboldianum - flower budding and below 0.05 in 11 pairs, whereas the YDIs over 0.40 were 4 pairs comprising of Prunus leveilleana - budding (0.51). Coefficient of variation of Tn was 0.01 in A. hirsuta - budding and below 0.05 in 8 pairs. The Tns over 0.40 were 5 pairs comprising of F. koreana - flower budding (0.66).

• Korean Journal of Agricultural and Forest Meteorology
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• v.25 no.4
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• pp.359-367
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• 2023

Grapes are one of the most important fruit trees both domestically and globally. Recently, changes in plant phenology and frequent low temperatures due to climate change are increasing the possibility of damage to grape shoots in spring, which is a serious threat to grape production. This study was conducted to investigated the severity of shoots damage and the change of free sugar content in the plant organs by phenological stage, especially, from germination to leafing period. Furthermore, in order to compare the cold hardiness among grape varieties including 'Campbell Early', 'Kyoho' and 'Shine Muscat' widely grown in Korea, lethal temperature (LT₅₀) and free sugar content by grape variety were analyzed. Shoot damage by low temperatures continued to increase as the phenological stage progressed gradually, from the bud burst to the fourth leafing stage. On the other hand, the free sugar content of each organ except leaves continued to decrease, showing pattern to similar to cold hardiness. This indicates a close relationship between free sugar content and cold hardiness. In terms of cold hardiness comparison among grape varieties, 'Shine Muscat' showed the highest cold resistance in the leafing stage with the lowest LT₅₀ and the highest total free sugar content. Next was 'Kyoho' and 'Campbell Early'. There are clear differences in cold hardiness depending on the variety. However, it is not the same at all growth stage. It may change according to phenological stage and influenced by free sugar content at that time.