• 유체기계공업학회:학술대회논문집
• /
• 2006.08a
• /
• pp.263-264
• /
• 2006

In this study, the threshold wind speed that causes physical damage on Kiwi fruit plant was investigated through wind tunnel experiments. Total 30 samples of Kiwi fruit branches were tested. On average, the wind speeds for tearing leaves and breaking side branch from the main branch were about 20m/s and 21.7m/s, respectively. For the cases of broken branches, the average length and diameter of the branches were 587.5mm and 7.2mm, respectively. The discoloration and dehydration of Kiwi plant were also observed by photographing leaves and branches after 24 hour later of the wind damage. In addition, the shelter effect of porous wind fences which have been used at agricultural districts was examined with varying several parameters.

• 한국생물공학회:학술대회논문집
• /
• 2000.04a
• /
• pp.527-530
• /
• 2000

A kiwi fruit ,called as the Chinese gooseberry, is originated from the Yangtze River Valley of Northern China and Zhejiang Province on the cost of Eastern China. Around 1950, a large mass production began at New Zealand with an Improved breeding. Plant origin actinidin from kiwi fruit belongs to the papain family of cysteine proteinase, which in plants includes papain from papaya, bromelain from pineapple, Cl4 protease from tomato and aleurain from barley. Actinidin is involved in the ripening-related gene family. In this study, protease gene of chinese wild kiwi fruit was isolated and characterized. 1.2kb PCR-amplified fragment was obtained from the total RNA using RT-PCR. pWACT-1 was obtained by subcloning of amplified fragment into pGEM-T Easy cloning vector and analyzed nucleotide sequence by DNA sequencing and amino acid sequence. In Result, high levels of homology between wild kiwi and New Zealand cultured-kiwi was obtained.

• The Korean Journal of Community Living Science
• /
• v.18 no.2
• /
• pp.241-246
• /
• 2007

This study was conducted to select and screen for an antifungal bacterial strain showing pathogen inhibitory activity against Diaporthe actinidiae, which causes stem-end rot in kiwi fruit. Four bacterial strains were isolated which strongly inhibit Diaporthe actinidiae from among two hundred and fifty bacterial strains screened from the soil where kiwi fruit were grown. By co-culturing bacterial strain #72 and the pathogen causing the stem-end rot of kiwi fruit, bacterial strain #72 showed 81.0% antifungal activity against Diaporthe actinidiae. Bacterial strain #72 was identified to be from the genus Bacillus sp. based on morphological and biochemical characterization. The bacterialization of culture broth for Bacillus sp. #72 which was sterilized at $121^{\circ}C$ for 15 minutes and than purified by $0.45{\mu}m$ membrane filter showed almost all of the antagonistic activity against Diaporthe actinidiae. We have also confirmed that in vitro treatment of Bacillus sp. #72 cultured in SD+B+P(sugar 5%, soy sauce 3%, beef extract 0.2%, peptone 0.2%) medium efficiently inhibited the growth of Diaporthe actinidiae responsible for stem-end rot in kiwi fruit.

• Journal of Apiculture
• /
• v.32 no.4
• /
• pp.327-332
• /
• 2017

In this study, we studied the changes in antioxidant activity of Actinidia arguta fruit of Autumn Sense cultivar during fruit ripening. The aim of this investigation was to find the knowledge of the changes of physiochemicals associated with fruit quality, antioxidant properties (free-radical scavenging activity and reducing power), total phenolics and vitamin C during fruit ripening. The highest free-radical scavenging activity (at $100{\mu}g/ml$) and reducing power (at $100{\mu}g/ml$) in A. arguta fruit were 78.57% and 0.22, respectively. Total phenolic content and vitamin C content in fruit of 10 days after fruit set were $639.48{\mu}g/g$ and $1052.2{\mu}g/g$, respectively. In general, the antioxidant activity and the related parameters, including total phenolic content and vitamin C content decreased during fruit ripening. These results improve knowledge of the effect of ripening on the antioxidant activity and related compounds contents that could help to establish the optimum A. arguta fruit harvest data for various usages.

• Horticultural Science & Technology
• /
• v.28 no.4
• /
• pp.708-710
• /
• 2010

'Skinny Green' is the third hairless-variety release by National Institute of Horticultural & Herbal Science (NIHHS) of Rural Development Administration (RDA) in Korea. It was bred by field crossing using the KN8903 as the mother plant, which had been selected from the crossbreeding of a Korean wild germplasm of tara vine with a male $Actinidia$ $deliciosa$ cv. Tomuri, and tara vine as the father plant collected from Korean mountains. The principal features of the final release are firstly, the fruit size not bigger than a mouthful bite with the average fruit weight not more than 19.3 g, and secondly, the thin and hairless edible fruit skin. It has green flesh color maintaining soluble solids and acid contents about $16.7^{\circ}Brix$ and 0.91% respectively. Its harvest season is usually in mid October. As it is not self-fertile it needs artificial pollination. Its tendency to produce maximum numbers of fruit requires thinning out of the fruits in a proper way.

• Journal of Bio-Environment Control
• /
• v.16 no.3
• /
• pp.252-257
• /
• 2007

This study was carried out to clarify the effects of antifungal Streptomyces sp. isolated from the soil grown kiwifruit on the growth inhibition of fruit rot (Botryosphaeria dothidea) infected in kiwi fruit plants in the southwestern districts of Jeonnam. Two hundred and fifty microorganisms were isolated and examined into the antifungal activity against Botryosphaeria dothidea. We screened and isolated six bacterial strains which have a strong inhibition against Botryosphaeria dothidea. And the best antifungal strain designated as the strain #120 showing 96.0% antifungal activity against Botryosphaeria dothidea was finally selected. The strain #120 was identified as Streptomyces sp. #120 based on its morphological, physiological, biochemical and chemotaxonomic characteristics.

• Research in Plant Disease
• /
• v.29 no.1
• /
• pp.45-51
• /
• 2023

The study was conducted to investigate the infestation and distribution of plant-parasitic nematodes on kiwi orchards in Korea. Plant parasitic nematodes genus and densities were investigated at a total of 102 sites in Jeollanam-do, Gyeongsangnam-do, and Jeju-do, which are the main production areas of domestic kiwi orchards. Plant parasitic nematodes detected were of 9 genera, including root-knot nematodes (Meloidogyne spp.), spiral nematodes (Helicotylenchus spp.), and needle nematodes (Paratylenchus spp.), and 56% of the 102 plantations were infected with root-knot nematodes. Root-knot nematodes were found to be the most important plant parasitic nematode in domestic kiwi orchards. The average density of root-knot nematodes is 97 per 300 cm³ soil, and there is concern about the kiwi yield reduction. As a result of identifying the root-knot nematode species: M. arenaria, M. hapla, M. incognita, and M. javanica. Among them, M. arenaria is the most dominant. As the plant parasitic nematode infection route in fruit trees is often spread through the transplantation of infected seedlings, attention should be paid to the production of nematode-free plants during the production and supply of kiwifruit plants.

• The Plant Pathology Journal
• /
• v.27 no.3
• /
• pp.257-265
• /
• 2011

During 2002-2008 in Korea, 455 extracts from myxobacteria consisting of 318 cellulolytic and 137 bacteriolytic myxobacteria were isolated, which were then screened for antifungal activity against the phytopathogens Botrytis cinerea, Colletotrichum acutatum, Penicillium sp., Pyricularia grisea, and Phytophthora capsici. 204 isolates had antifungal activity, causing both a clear zone due to blocked spore germination and inhibition of mycelial growth; most (199) were from cellulolytic (Sorangium cellulosum) and only five were from bacteriolytic myxobacteria. B. cinerea, the best controlled among the five tested pathogens, had a unique group of antifungal isolates of myxobacterial extracts compared to the other pathogens' groups. Among seventy-nine bioactive myxobacteria, four isolates, KYC 3130, KYC 3247, KYC 3248 and KYC 3270, were selected and all were cellulolytic. Liquid culture filtrates of these four myxobacteria were applied to tomato, cherry tomato, strawberry, and kiwi fruits 5 h before inoculation with gray mold conidia; then the treated fruits were placed in an airtight container and the experiment was repeated six to eight times. Incidence (%) of gray mold on fruit of the infected control treatment was 84-98%, whereas it was only 5-21% after the KYC 3270 treatment. After KYC 3270 treatment of the four fruits, mold control was 79-95%, which was highest among the filtrates and statistically the same as treatment with fludioxonil, a registered chemical against gray mold of stored fruits.

• Applied Biological Chemistry
• /
• v.39 no.6
• /
• pp.466-471
• /
• 1996

The survey on the chitinolytic activity of some plants was performed for the purpose of obtaining some reliable and inexpensive sources of chitinase. Rice, soybean for sprouting, kiwi fruit, almond and crude papain were investigated. Rice bran, seed coat of the soybean and the pericarp of kiwi fruit showed a considerable activity, while the bean after the removal of the seed coat, the mixture of rice integument and endosperm, polished rice, and defatted soybean powder didn't have any detectable activity. These crude enzymes have shown to contain both endo- and exochitinase activity. The effects of pH and temperature on the enzyme activity were variable. Furthermore we have observed the chitosanolytic activity from these enzyme Preparations. The rice bran had the highest activity in the enzymatic degradation of chitosan, and seed coat of soybean and the pericarp of kiwi fruit followed. On the basis of the fact that crude papain was not only commercially available but also the most potent in the endochitinase activity and the lowest in the exochitinase activity, we could conclude that crude papain was considered as the most suitable source of the chitinase among plants studied in this paper. In addition, rice bran was worth further investigation from the point of utilizing agricultural by-product.

• Korean Journal of Plant Resources
• /
• v.24 no.1
• /
• pp.61-68
• /
• 2011

Loperamide-induced constipation reduced gastric emptying, small-intestinal and colonic motility, and these effects were prevented by Actindia chinensis(Gold Kiwi Fruit, GKF). In this study, the effects of Actindia chinensis on constipated male Sprague-Dawley rats induced by loperamide(2 mg/kg, s.c.,5 days) were investigated. Rats were randomly assigned to the normal control rats(regular diet), constipated rats(regular diet plus loperamide), constipated rats treated with 2.5% GKF(regular diet supplemented with 2.5% GKF plus loperamide), constipated rats treated with 5% GKF (regular diet supplemented with 5% GKF plus loperamide). There was less fecal excretion and lower fecal water content in loperamide-treated rats than in control rats. Oral administration of GKF blocked the decrease of fecal excretion and fecal water content in the loperamide-treated rats. Mucus production of crypt cell and mucus contents at fecal and mucosa surface were reduced by loperamide-treated rat. But colonic crypt cell contained increased mucin in the GKF treated group and mucus layer stained with alcian blue was significantly thicker in GKF treated rats compared with in loperamide-treated rats. In isolated rat ileum, loperamide produced inhibition of ileal motility. Pretreatment with methanolic extracts of GKF in isolated rat ileum prevented inhibition by loperamide. These findings indicated that the GKF was effective for alleviation of inhibition of colonic peristalsis by loperamide and that GKF might be of value in the prevention of constipation.