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블루베리의 주요 품종군은 북부형(Vaccinium corymbosum L.), 남부형(Vaccinium corymbosum hybrid)하이부쉬 블루베리와 래빗아이 블루베리(Vaccinium ashei Reade)로 나뉜다. 이들 품종군은 공통 적으로 배수성이 좋은 산성토양과 뿌리털이 없는 천근성 뿌리구조로, 보비력과 양분이용이 매우 취약한 환경을 가지고 있다. 따라서 본 연구는 시비효율성 증대를 위하여 래빗아이 블루베리의 생육특성에 미 치는 관비효과를 구명하고자 수행하였다. 시험장소는 경남 남해에 소재한 국립원예특작 과학원 남해출 장소 시설포장에서, 2013년 4년생 ‘Brightwell’(V.ashei Reade)레빗아이 블루베리 품종을 완숙유기물(피 트모스) 30%(v/v)혼합된 토양에 재식하여 수행하였다. 시비는 오레곤 주립대학에서 제공하는 표준시비 량 14g plant -1 의 관행시비와 4수준의 관비를 처리하여 양분흡수량과 수체생육 그리고 과실특성을 조사 하였다. 시비방법에 따른 수체생육과 과실생산량은 관비시비가 효과적이었으며, 관비수준별 시비효과는 표준시비량의 50%처리가 가장 효과적이었다. 처리별 엽중 질소함량은 표준시비량의 50% 관비처리가 14.4g kg -1 으로 가장 높았으나, 200% 관비구는 11.5 g kg -1 으로 가장 낮았다. 처리별 엽중 인산함량은 유의차가 나타나지 않았으나, 칼리와 칼슘 그리고 마그네슘함량은 표준시비량의 50%관비처리에서 가장 높았으며, 시비량의 증가는 엽중 무기성분 함량을 낮추는 경향을 나타냈다. 처리별 수관면적은 관행시 비가 4.86 m 3 으로 가장 낮은 수준을 보였으며, 50% 관비처리가 9.61 m 3 로 가장 높았다. 이와같이 50% 관비처리의 높은 시비효과는 각각 3,650 g plant과 12,849 g plant을 나타낸 건물중과 과실생산량에서 도 유사한 경향이었다. 한편 시비방법과 관비수준에 따른 과실의 안토시아닌과 당 그리고 산함량 등 과 실품질은 일정한 경향을 나타내지 않았다.

BACKGROUND: This study was conducted to investigate the effect of the unexpected early loss of leaves on a newly-bred kiwifruit on the regrowth of axillary buds the current season and the early growth and development the following year. METHODS AND RESULTS: The vines were defoliated on Jul. 18, Aug. 16, and Sep. 17 in 2012 and on Jul. 16, Aug. 13, and Sep. 12 in 2013. The vines were defoliated 0 (control), 50, and 100% of the total number of leaves on a vine. The regrowth of axillary buds at 30 days after defoliation increased in proportion to defoliation degrees regardless of the defoliated time. Defoliation the previous season did not influence percent budbreak the next season. Percentage of floral shoots of the control vines was 27.4%, each bearing 2-3 flowers. In those vines defoliated 100% in August and September, however, percent floral shoots and number of flowers significantly reduced. CONCLUSION(S): Defoliation in July, August, and September didnot affect percent budbreak the following year regardless of degrees of defoliation. A 100% defoliation in August and September significantly reduced flowering the following year compared to the control; that in August resulted in no floral buds at all.

Floral Bud Cold Hardiness and Cultural Safety Zone in Rabbiteye Blueberry Cultivars Hong-Lim Kim, Yong-Bum Kwack, Jeom-Hwa Han, Pill-Kyung Oh, Won-Byoung Chae, Seong-Cheol Kim, Mok-Jong Kim and Jin-Gook Kim, (Namhae Sub‐Station, NIHHS, RDA, Namhae 668‐812, Korea, Fruit Research Division, NIHHS, RDA, Suwon 440-706, Korea, Vegetable Research Division, NIHHS, RDA, Suwon 440‐706, Korea, Department of Horticulture, Gyeongsang National University, Jinju 660‐701, Korea)

Received: 18 September 2014 / Revised: 10 November 2014 / Accepted: 12 November 2014 Copyright c 2014 The Korean Society of Environmental Agriculture This is an Open-Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/3.0) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.

In May 2014, sclerotinia rot symptoms caused by Sclerotinia sclerotiorum were observed on stored kiwifruit in Jinju, South Korea. The symptoms appeared as soft, water-soaked lesions on fruit covered with a white mycelium. The morphological characteristics and the internal transcribed spacer sequences of rRNA of the pathogen isolated from the sclerotinia rot showed it to be S. sclerotiorum. This was confirmed by performing a pathogenicity test with pure cultures of S. sclerotiorum and by reisolating S. sclerotiorum from artificially inoculated kiwifruits. Our results should help promote a better understanding of the diseases that affect kiwifruit and improve practices for postharvest disease control in the kiwifruit industry.

BACKGROUND: Kiwifruit, which was introduced to Korea in late 1970s, is a warm-temperate fruit tree, whose leaves are easily damaged by wind because of their large size. To produce high quality fruits, efficient windbreak is necessary to protect leaves until harvest. In Korea, typhoons from July onwards usually influence the production of kiwifruit. Damages from typhoons include low fruit quality in the current year and low flowering ratio the following year. This study was conducted to investigate the effect of early defoliation of kiwifruit vines from July to October on the regrowth of shoot axillary buds the current year and bud break and flowering the following year. METHODS AND RESULTS: Scions of kiwifruit cultivar 'Goldrush' were veneer grafted onto five-year-old Actinidia deliciosa rootstocks, planted in Wagner pots (13L) and grown in a rain shelter. Kiwifruit leaves in the proximity of leaf stalk were cut by lopping shears to simulate mechanical damage from typhoon since only leaf stalks were left when kiwifruit vines were damaged by typhoons. Kiwifruit vines were defoliated from July 15 to October 14 with one monthintervals and degrees of defoliation were 0, 25, 50, 75 and 100%. All experiments were conducted in the rain shelter and replicated at least five times. Defoliation in July 15 resulted in a high regrowth ratio of 20-40% regardless of degree of defoliation but that in August 16 showed only 5.8% of regrowth ratio in the no defoliation treatment; however, more than 25% of defoliation in August 16 showed 17-23% of regrowth ratio. In September 15, regrowth ratio decreased further to less than 10% in all treatments and no regrowth was observed in October 14. Percent bud break of all defoliation treatments were not significant in comparison to 64.7% in no defoliation except for 42.1% and 42.9% in 100% defoliation in July 15 and August 16, respectively. Floral shoot in the no defoliation treatment was 70.2% and defoliation of 50% or less resulted in the same or increased floral shoot ratio in July 15, August 16, and September 15; however, defoliation in October 14 showed no difference in all treatments. In flower number per floral shoot, 2-3 flowers appeared in no defoliation and only 1 flower was observed when the vines were defoliated more than 50% in July 15 and September 15. In October 14, contrary to the floral shoot ratio, flower number decreased with increased defoliation. CONCLUSION(S): Therefore, it is suggested that dormancy of 'Goldrush' axillary buds, was started in August and completed in October. The effect of defoliation on bud break of axillary buds the following year was insignificant, except for 100% defoliation in July 15 and August 16. From July 15 to September 15, floral bud ratio was significantly reduced when more than 50% of leaves were defoliated compared to no defoliation. Also, the number of flowers per flower-bearing shoot the following year decreased by less than 50% when compared to no defoliation, and this decrease was more prominent in September 15 than July 15 and August 16.

The contents of soluble sugars (sucrose, fructose, glucose, maltose and raffinose), vitamin C and free amino acids (34 compounds, essential and non-essential) were quantified in open-field and greenhouse-grown spinaches in response to cold stress using liquid chromatography. In general, greenhouse cultivation produced nutritionally high value spinach in a shorter growing period, where the soluble sugars, vitamin C and total amino acids concentrations, including essential were in larger amounts compared to those grown in open-field scenarios. Further, low temperature exposure of spinach during a shorter growth period resulted in the production of spinach with high sucrose, ascorbate, proline, gamma-aminobutyric acid, valine and leucine content, and these constitute the most important energy/nutrient sources. In conclusion, cultivation of spinach in greenhouse at a low temperature (4-7°C) and exposure for a shorter period (7-21days) before harvest is recommended. This strategy will produce a high quality product that people can eat.

BACKGROUND: The fruit quality and flowering characteristics of Kiwifruit (A. deliciosa cv. Hayward) in the following year is known to be affected by the extent and timing of defoliation of the current year. In korea, the production of kiwi, which is a perennial, straggling deciduous warm-temperate fruit, is often restricted by wind damage due to typhoons resulting to defoliation at the middle season of its growing period. In this paper, we report the effect of the different timing of defoliation and severities at the current season to the kiwifruit quality. METHODS AND RESULTS: Twenty seven-year-old 'Hayward' trees grown under polyethylene film rain-shelter were defoliated in different days from August to September at seven day-intervals. In each day, 0, 25, 50, 75 and 100% of leaves were removed from the trees. Fruits from each treatment were classified into four floating types (L: lying in bottom, S: standing on bottom, F: floating and SF: floating at the surface of water) by submerging them into tap water. Defoliation of kiwifruit trees in August and September caused air holes in locules of inner pericarp. Increased number of air hole in locules of a fruit was observed in floating types F and SF, and most of the air holes were located in stem end. The defoliation of trees in August significantly reduced the ratio of L-floating type fruits, which have the least number of locule air holes. The extent of defoliation also affected the distribution of the four types, the more leaves removed, the less L-floating type fruits harvested. The weight of fruits from trees defoliated in August was lower than that of fruits from September. Soluble solids content decreased as the number of locule air holes increased. Negative correlations were observed between the extent of defoliation and the weight and soluble solids content of fruits. CONCLUSION: Early defoliation effect on kiwifruit locule air hole occurrence and fruit quality were more severe in August than in September. And also if the defoliation severity is over 25%, severe fruit quality reduction expected to happen due to increase of fruit locule air hole in the inner pericarp.

A new promising kiwifruit, 'Halla Gold' variety with yellow flesh and being harvested in October, was developed at the Agricultural Research Center for Climate Change, National Institute of Horticultural and Herbal Science, Rural Development Administration, Korea in 2007. This variety was derived from the seedling population crossed between Actinidia chinensis cv. Golden Yellow and A. chinensis cv. Songongu in 1997. It was selected out of 2,971 seedlings. Characteristic trials were carried out from 2001 to 2003. After the selection, adaptability test was also conducted at kiwifruit orchards in Jeju Island from 2003 to 2007. Shoots of 'Halla Gold' sprout slightly stronger than those of 'Jecy Gold' but weaker than 'Hort16A' and the color of leaf is green. Fruit shape is oblong and fruit skin color is yellowish-dark green without hair. The average weight of fruit is 106.3 g. Fruit has a moderate size soft core, yellow pericarp, and fragile and juicy flesh. Soluble solids content is Brix and acidity is 1.4%. The harvesting time is about 10 days earlier than 'Jecy Gold' and about 20 days ahead of 'Hort16A'. The storage life is about 90 days at . This variety can be recommended for cultivating at low land area bellow 100 m sea level in Jeju Island or under shelter to prevent disease and cold injury.