Chun Hwan Kim

Impact of Elevating Temperature Based on Climate Change Scenarios on Growth and Fruit Quality of Red Pepper (Capsicum annuum L.)

This study was conducted to determine the impact of temperature elevated based on climate change scenario on growth and fruit quality of red pepper (Capsicum annuum L.) in walk-in plant growth chambers. The intraday temperatures of climate normal years (IT) were determined using intraday mean temperatures of climatic normal years (1971~2000) in the Andong Province during the growing season (May 1~July 30). Red pepper plants were cultivated under different temperatures (starting at IT rise by up to 6 o C, 2 o C increment). Plant height, stem diameter, branch number, leaf number, fresh weight and dry weight increased under the temperatures higher than IT. The number of flower was the greatest under IT+2 o C (mean temperature at 22.8 o C). The total number and the weight of fruits were the highest under IT+2 o C. While the fruit weight, fruit length and fruit diameter decreased more than IT+2 o C as the temperature increased gradually. These results concluded that in condition that the current diurnal temperature change cycle is maintained in Andong area, in accordance with climate change scenarios, when the temperature rise 2 o C higher than intraday temperature of Andong area the quantity of pepper fruits will increase while maintaining quality, but increases more than that degree yields are expected to decrease significantly. This result suggests that the fruit yield could increase under IT+2 o C and fruit quality could maintain great, but the fruit yield could decrease under the temperatures higher than IT+2 o C.

Impact of Elevated Temperature in Growing Season on Growth and Fruit Quality of Red Pepper (Capsicum annuum L.)

This study was conducted to determine the impact of elevated temperature in growing season on the growth and fruit quality of red pepper (Capsicum annuum L.) by cultivating pepper in the temperature gradient tunnels. Plant height, stem diameter, leaf number and total leaf area, fresh weight and dry weight increased at ambient + 2 o C temperature, whereas each leaf area decreased as temperature increased. The plants grown under ambient + 2 o C temperature showed the greatest number of flower and fruit. Fruit weight, fruit length and fruit diameter decreased as the temperature increasing gradually. Total fruit number, total fruit weight and total dry fruit weight was the highest at ambient + 2 o C temperature. Major free sugars of red pepper fruit were fructose and glucose. Free sugar content of red pepper according to the differences in harvesting times and in growth temperature showed a little differences. The yield of red pepper fruit at ambient + 2 o C temperature increased by 13% compared with the control. However, the yield of red pepper fruit at ambient + 4 o C temperature decreased by 20% as compared to control. Non-marketable fruits (diseased fruit, malformed fruit and small sized fruit) increased as the temperature rised.

Discrimination of citrus fruits using FT-IR fingerprinting by quantitative prediction of bioactive compounds

High throughput screening of citrus samples containing elevated concentrations of total carotenoids, flavonoids, and phenolic compounds was accomplished using ultraviolet–visible spectroscopy and Fourier transform infrared (FT-IR) spectroscopy, combined with multivariate analysis. Principal component analysis and partial least squares discriminant analysis using FT-IR spectra were able to differentiate seven citrus fruit groups into three distinct clusters corresponding to their taxonomic relationship. Quantitative prediction modeling of total carotenoids, flavonoids, and phenolic compounds in citrus fruit was established using a partial least squares regression algorithm from the FT-IR spectra. The regression coefficients (R2) of predicted and estimated values of total carotenoids, flavonoids, and phenolic compounds were all 0.99. The results indicated that accurate quantitative predictions of total carotenoids, flavonoids, and phenolic compounds were possible from citrus fruit FT-IR spectra, and that the resulting quantitative prediction model might be useful as a rapid selection tool for citrus fruits containing elevated carotenoids, flavonoids, and phenolic compounds.

Effects of Planting Date on Growth and Yield of Bitter Gourd (Mormordica charantia L.) in Rain Shielding Plastic House

The experiment was carried out to examine the effects of planting date on the growth and marketable yield of bitter gourd grown in rain-shield plastic houses. Bitter gourd cv ‘Dragon’ seedlings were separately transplanted during the months of June, July and August, 2015. The training method of all plants was made with four lateral vines and pinching the main vine. Lateral length of plants exhibited no significant difference between each planting date. However, bitter gourd planted in June had significantly higher main stem diameter than those treatments planted on August. The application of planting date was found effective in increasing marketable yield and number of fruits. June, as a planting date, had the highest marketable yield (6,439kg/10a), whereas bitter gourd planted in August had the lowest yield (870kg/10a) which were also consistent in terms of the number of fruits. Fruit length and diameter had no significant differences as affected by treatments. Therefore, planting date of bitter gourd in June was effective in increasing yield of fruit in rain-shield plastic house conditions Additional key words : marketable yield, transplanting, stem training method, lateral vine

Effects of Apex Removal on the Growth and Yield of Artichoke by Planting Times

Apex removal is a common practice in artichoke cultivation to harvest heads of lateral shoots. This experiment was carried out to investigate the effect of apex removal by different planting times on the growth and yield of Artichoke (Cynara scolymus L.) in open field. Two treatments (apex removal and no apex removal) at three different planting times (1: Sep. 27, 2011, 2: March 29, 2012, and 3: Sep. 21, 2012) were tested using ‘Green Globe’ variety. There was no difference in the head characteristics and the number of harvested head between the treatments. The head weight was heavier in no apex removal of 242.7 g than the apex removal of 170.8 g. The yield also increased in no apex removal by 25% (1,249 kg/10a) compared to the apex removal of 997 kg/10a at the first planting time. At the second planting time, there was no difference in the head weights between the treatments. But the number of the harvested head was higher in no apex removal with 10.8 than 8.2 of the apex removal. The yield of no apex removal was 2,660 kg/10a, which was higher than 1,848 kg/10a of apex removal. At the third planting time, the head weight increased in no apex removal with 253.5 g compared to the apex removal with 218.7 g. The yield of no apex removal was 1,405 kg/10a, which was higher than 1,148 kg/10a of the apex removal. All the tests at 3 different planting times showed that the artichoke yields were higher in no apex removal than in apex removal. Therefore, it is desirable to cultivate artichoke without removing the apex for the higher yield and labor saving in open-field cultivation in Jeju island. Additional key words : flower bud, lateral shoot, open culture, transplanting

Effect of Vernalizing Temperature on Growth and Yield of Globe Artichoke

This study was conducted to produce heads of artichoke in July in Korea. The artichoke was planted in the Autumn and it could be reaped heads of artichokes in late of May in Korea. It can inform us that the artichoke need under some low temperature during the Winter to open flowers. In order to harvest heads of artichoke in the Summer two kinds of cultivar ‘Green Globe’ and ‘Imperial Star’ those were grown for 4 weeks in green house of 17℃ which were treated at 3, 6, 9 and 12oC chamber for 4 weeks and then planted the 8th April. Plant distance was 150 × 50 cm. After 3 months most of artichoke of ‘Imperial Star (IS)’ made heads. Especially, the artichokes ‘IS’ were treated at 6℃ made heads 63% of plants but those at 12℃ made heads 33% and the artichokes (no treatment at low temperature) grown in greenhouse at 17℃ for 8 weeks made heads 5% of plants. ‘Green Globe (GG)’ made heads 28% of plants at 9℃ and 10% at 12℃, and ‘GG’ grown in greenhouse at 17℃ for 8 weeks never had made any head. The weights of head were 97 g and 86 g in ‘IS’ and ‘GG’ respectively. The yield of heads were 215 and 108 kg/10a in ‘IS’ and ‘GG’ respectively.