• Current Research on Agriculture and Life Sciences
• /
• v.11
• /
• pp.25-30
• /
• 1993

The buds of Hayward/Bruno tree were damaged from $-7^{\circ}C$ but serious damage was found on the buds treated at $-15^{\circ}C$ and $19^{\circ}C$. The bark tissue was more suceptible to low temperature than the bud. The trees were survived and bursted their at all on the top of the graft union and new shoots were formed from the rootstock of the tree. Yellowish area on the leaf surface was found, which is believed that as a result of low temperature. From these, the kiwifruit trees must be grafted with cold tolerant rootstocks will be clarified in future.

• Journal of Bio-Environment Control
• /
• v.15 no.4
• /
• pp.352-357
• /
• 2006

Results of development and activity of roots by rootstock sort of oriental melon were followed; Grafted seedlings had higher root growth than self-roots seedlings and among grafted seedlings, Shintozoa and Elite rootstocks had higher root growth. Grafted seedlings had more xylem exudate, which connects activity of roots, than self-root seedlings. Development of roots and increase of xylem exudate were better in higher temperature. Marketable yield was higher in grafted seedling and quality of fruit was higher in self-root seedling.

• Journal of Biosystems Engineering
• /
• v.28 no.6
• /
• pp.525-530
• /
• 2003

This study was carried out to develop a vacuum nozzle seeder for the automation of large seeds sowing of fruit vegetables and rootstocks. Moreover, the seeding efficiency was examined to find the optimum operating condition considering high precision seeding. The important operating factors for high seeding rate were typically nozzle diameter and absorbing vacuum pressure. The optimum nozzle diameters were found 1.5, 1.5 and 2.0 mm for Chambak, Tuktozwa and Hukjong while the optimum vacuum pressures were 8.0㎪, 10.6㎪ and 5.3㎪, respectively. Under the optimum operating condition, the results indicated that the maximum seeding rates were 97.6％, 98.8％ and 97.6％ respectively for Chambak Tuktozwa and Hukjong. The vibrating acceleration of the hopper did not make any significant effects on the seeding rate when the vacuum pressure reached 8.0㎪ and the sowing rate became higher with lighter seed. As the seed became heavier, the larger diameter of nozzle was recommended 1.5mm of the nozzle diameter was found to be applied for the experimental seeds. The vacuum pressure was also found 8.0㎪ - 13.3㎪ at that time.

• Journal of Biosystems Engineering
• /
• v.33 no.6
• /
• pp.453-461
• /
• 2008

This study was conducted to develop a root-removed splice grafting system for cucurbitaceous vegetables, mainly watermelon and cucumber seedlings, for the seedlings factories where currently most of seedlings grafting works are carried out by manual works. The major results of the study are as follows. The dimensions of rootstocks and scions, except cotyledon width, of root- removed splice grafting of watermelon and cucumber were shown to be varied within the 2.5-fold range. The growth status of seedlings were not consistent in terms of cotyledon sprouting direction and angle which were considered as one of the important factors for in root-removed splice grafting. The grafting work of root-removed splice for grafted watermelon and cucumber could be divided by four sub-operations: seedling supplying, cutting, clipping and potting, while a part or all root of the rootstock was removed in the seedlings supplying operation. The cutting angles of the rootstock and scion were $34-45^{\circ}$ and $20-45^{\circ}$, respectively, while the stem length of the scion varied from 6 mm to 12 mm. The splices of rootstock and scion were heaped up in parallel and then fixed by a clip. It indicated that the ideal grafting system, adopting conventional grafting processes of seedlings specifications as well as conventionally manual root-removed splice grafting method, performed very well for seedlings gripping and transporting, supplying clip, clipping and discharging grafted seedlings while workers supplied seedlings to the semi-automatical system.

• Journal of Bio-Environment Control
• /
• v.16 no.3
• /
• pp.174-179
• /
• 2007

Although the relationship between fermentation and factors such as soil water, redox potential, rootstocks and climatic conditions has been reported, its mechanism of fermentation is still not clear. Transpirations of leaf and fruit at different climatic conditions, influence of soil water potential and atmospheric vapor pressure deficit (VPD) on fermentation were evaluated. Transpiration rate decreased with decreasing soil temperature and soil water potential. Low VPD conditions which occurred during low air temperature and high humidity also decreased transipration rate. These data exhibit that fruit water balance affected by various factors relate to transpiration. Our results also indicate that high hydraulic conductance of root, high soil water potential and low VPD condition exert a significant effect on fermention of oriental melon and so called "water filled fruit".

• Journal of Bio-Environment Control
• /
• v.15 no.4
• /
• pp.417-420
• /
• 2006

To investigated the dormancy of chicory (Cichorium intybus L.) for production of high quality rootstocks, growth characteristics and abscisic acid (ABA) contents was conducted. The accumulation hours below $5^{\circ}C$ in field was increased slowly from October 7 to December 3, but there after increased largely. The rootstock weights was increased from the end of October to December 3, there after was not changed to December 3. ABA contents within the rootstock was not changed from October 7 to December 3, and there was suddenly increased for two weeks to December 24. As results of the sudden changed date of accumulation hours below $5^{\circ}C$, stopped date and period of rootstock growth, and sudden changed period of ABA contents, chicory has internal dormancy for two weeks from December 3 and low temperature requirement hours for the dormancy breaking is about 240.

• Horticultural Science & Technology
• /
• v.35 no.2
• /
• pp.220-231
• /
• 2017

Grafting using a pumpkin (Cucurbita sp.) rootstock is an effective way to improve cucumber (Cucumis sativus) resistance to a combination of chilling and salinity stresses. We evaluated the tolerance of 15 pumpkin cultivars to chilling, salinity, and combined stresses at the germination and seedling stages. Selected plant characteristics, including germination rate, germination potential, germination index, plant height, stem thickness, fresh weight, and dry weight, were analyzed. We used the unweighted pair group method with arithmetic mean for cluster analyses to determine the stress tolerance levels of the pumpkin cultivars. The 15 cultivars were divided into three clusters: tolerant, moderately tolerant, and susceptible to stress treatments. The stress tolerances of all cultivars were variable in the germination and seedling stages, and most cultivars were not tolerant to individual treatments of chilling or salinity stresses at both stages. These results suggest that identifying suitable cultivars for use as rootstock during cucumber grafting should involve the evaluation of stress tolerance during different growth stages. Additionally, cultivars tolerant to chilling stress may not be tolerant to salinity stress; therefore, the choice of pumpkin rootstock should depend on where the grafted plant will be grown. Cultivars tolerant to a combination of chilling and salinity stresses may be useful as rootstock for cucumber grafting. Our findings may serve as reference material for choosing appropriate pumpkin rootstocks for cucumber grafting.

• The Plant Pathology Journal
• /
• v.32 no.6
• /
• pp.489-499
• /
• 2016

Green shoot cuttings of 10 different grapevine species were inoculated with Agrobacterium vitis to find disease-related metabolites in the grapevine. Crown galls formed 60 days after inoculation varied in gall severity (GS) evaluated by gall incidence (GI) and gall diameter (GD), which were classified into three response types as RR (low GI and small GD), SR (high GI and small GD), and SS (high GI and large GD), corresponding to resistant, moderately resistant, and susceptible responses, respectively. In this, 4, 4, and 2 Vitis species were classified into RR, SR, and SS, respectively. Gas chromatography mass spectrometry (GC-MS) analysis of the grapevine stem metabolites with A. vitis infection showed 134 metabolites in various compound classes critically occurred, which were differentially clustered with the response types by the principal component analysis. Multivariate analysis of the metabolite profile revealed that 11 metabolites increased significantly in relation to the response types, mostly at post-inoculation stages, more prevalently (8 metabolites) at two days after inoculation than other stages, and more related to SS (7 metabolites) than RR (3 metabolites) or SR (one metabolite). This suggests most of the disease-related metabolites may be rarely pre-existing but mostly induced by pathogen infection largely for facilitating gall development except stilbene compound resveratrol, a phytoalexin that may be involved in the resistance response. All of these aspects may be used for the selection of resistant grapevine cultivars and their rootstocks for the control of the crown gall disease of the grapevine.

• Research in Plant Disease
• /
• v.14 no.1
• /
• pp.10-14
• /
• 2008

Batcterial wilt caused by Ralstonia solanacearum is one of important and widespread diseases worldwide as well as in Korea. Bacterial wilt disease caused by R. solanacearum has been reported mainly in solanaceous crops including eggplant (Solanum melongena), tomato (Solanum lycopersicum), potato (S. tuberosum), and pepper (Capsicum annuum). A total of 48 strains of R. solanacearum from eggplant were collected during 2005 and 2006. They were confirmed as R. solanacearum by PCR amplification with primer pair flipcF/flipcR resulting in production of 470-bp DNA fragment. The 15 isolates exhibited pathogenicity on eggplant and tomato, but less virulent on pepper than other species. The biovar of collected isolates, which have been reported of five types worldwide, were classified as biovars 3 and 4 by physiological test. Biovar 4 was the dormant type without pathogenicity on eggplant rootstock, whereas biovar 3 had pathogenicity on eggplant rootstocks that is resistant to R. solanacearum, indicating necessity of breeding new rootstock with resistance to R. solanacearum biovar 3

• Journal of Plant Biotechnology
• /
• v.37 no.4
• /
• pp.408-413
• /
• 2010

The paper reviewed research status and outlook of genetic transformation in fruit trees in Korea. Genetic transformation has been long considered as an alternative technique overcoming limitation of conventional breeding and conducted since early 1990's. An efficient genetic transformation was established with major cultivars of apple, even in Fuji and Gamhong, and some transgenic apple plants have been transferred into the greenhouse for further analysis of gene expression. A few successes of genetic transformation have been reported and application to a variety of cultivars tried in citrus and kiwifruit. Successful genetic transformation has not been reported in the other fruit trees including grapevine, yet and it is considered being at the level of research. Those factors including replacement of antibiotics as a selective agent, use of transgenic rootstocks and manipulation of gene expression at proper parts and developmental stages have been prerequisites for the rapid commercialization of transgenic fruit plants.