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Song J.Y.,Gyeongsang National University | Sivanesan I.,Gyeongsang National University | An C.G.,Gyeongnam Agricultural Research and Extension Services | Jeong B.R.,Gyeongsang National University
African Journal of Biotechnology | Year: 2010

A simple and efficient protocol was developed for in vitro propagation of two miniature paprika cultivars. Seeds of miniature paprika (Capsicum annuum) 'Hivita Red' and 'Hivita Yellow' were decontaminated and placed in a petri dish containing a half-strength MS medium and then were incubated in the dark for 7 10 days for germination. Leaf explants excised from one month-old aseptic seedlings were cultured on a MS medium supplemented with TDZ (0.1, 0.5, 1.0, 2.0, or 3.0 mgL -1) alone or in a combination with NAA (0.1 or 0.01 mgL -1) for four weeks. The highest number of regenerated shoot buds was obtained when leaf explants were cultured on a MS medium supplemented with 2.0 mgL -1 TDZ and 0.1 mgL -1 NAA with an average shoots per explant of 8.0 in 'Hivita Red' and 5.6 in 'Hivita Yellow'. Regenerated shoot buds were separated and transferred onto a MS medium without growth regulators for shoot growth and rooting. Plantlets were successfully acclimatized in a greenhouse and cultivated for three months. After about two months, they started to produce flowers and continuously produced fruits. Morphology and fruit shape of regenerated plants were normal and plants set seeds as the same as to the seed-raised plants. © 2010 Academic Journals.

Choi S.-T.,Sweet Persimmon Research Institute | Kang S.-M.,Gyeongsang National University | Park D.-S.,Sweet Persimmon Research Institute | Hong K.-P.,Sweet Persimmon Research Institute | Rho C.-W.,Gyeongnam Agricultural Research and Extension Services
Scientia Horticulturae | Year: 2011

Responses of pot-grown persimmon trees (Diospyros kaki cv. 'Fuyu') with two different leaf/fruit (L/F) ratios and three different fertigation levels were studied. On July 2, the L/F ratios of 4-year-old trees were adjusted to 20 and 10 by fruit thinning. From July 4 to August 26, each pot was fertigated with a solution containing 0-0. g (none), 10-8. g (medium), or 20-16. g (high) of nitrogen (N) and potassium (K), respectively. The L/F ratio of 10 resulted in higher yields but smaller fruits containing lower soluble solids than the ratio of 20. The non-fertigated trees with the L/F ratio of 10 produced the smallest fruits, but the medium fertigation increased the size of the fruit at this ratio. The high fertigation level decreased fruit skin color at both ratios. Fruit dry weight increased the most among the tree components, accounting for 48-57% of the tree total dry weight at the L/F ratio of 20 and for 64-72% at the ratio of 10. The increase in tree total dry weight at the ratio of 10 was greater than that at the ratio of 20. The trees receiving medium fertigation had higher tree total dry weights than those receiving high fertigation, especially at the ratio of 10. As the L/F ratio changed to 10 from 20, the percentages of N and K partitioned to fruits in the non-fertigated trees increased from 38% to 51% and from 67% to 96%, respectively, of the tree total N and K increases; the percentage decreased with increasing fertigation level. Although fertigation significantly increased total N and K contents of the tree, the increase in K at the ratio of 10 was less in high fertigation rather than in the medium level. The results indicated that adjusting supplemental N and K was necessary to ensure fruit growth and N and K accumulation for trees with high fruit loads, but high levels of fertigation are not necessarily preferable. © 2011 Elsevier B.V.

Kim G.D.,Chonnam National University | Kim G.D.,Bohea Brewery Co. | Lee Y.S.,Jeonnam Agricultural Research and Extension Services | Cho J.-Y.,Chonnam National University | And 7 more authors.
Journal of Agricultural and Food Chemistry | Year: 2010

The aim of this study was to evaluate the chemical compositions and antioxidative activities of hot pepper fruits cultivated with strict management by organic and conventional agricultural practices. The ascorbic acid content in the organically grown hot pepper (OGP) was significantly higher than that of conventionally grown hot pepper (CGP) in both green and red fruits. The content of other bioactive compounds such as flavonoids (apigenin, luteolin, quercetin) and total phenolics in OGP was typically higher than in CGP regardless of fruit color. In addition, the ABTS+ radical-scavenging activity of OGP red fruits was significantly higher than that of CGP red fruits. Moreover, regardless of the color of the fruits, a higher antioxidative activity was observed in blood plasma from rats administered the OGP fruit extracts than in blood plasma from rats administered the CGP fruit extracts. It was hypothesized that the higher antioxidant activity of the OGP fruits may have resulted from the higher antioxidant content in the OGP fruits. These results suggest that consumption of pepper fruits may increase antioxidant activity in the blood, and OGP fruits may be more effective in increasing this antioxidant activity than CGP fruits. © 2010 American Chemical Society.

Xia C.,Pusan National University | Lee J.-M.,Pusan National University | Li Y.,Pusan National University | Chung B.-K.,Gyeongnam Agricultural Research and Extension Services | Chon T.-S.,Pusan National University
Optical Engineering | Year: 2012

We introduce a multifractal analysis for detecting the small-size pest (e.g., whitefly) images from a sticky trap in situ. An automatic attraction system is utilized for collecting pests from greenhouse plants. We applied multifractal analysis to segment action of whitefly images based on the local singularity and global image characteristics. According to the theory of multifractal dimension, the candidate blobs of whiteflies are initially defined from the sticky-trap image. Two schemes, fixed thresholding and regional minima obtainment, were utilized for feature extraction of candidate whitefly image areas. The experiment was conducted with the field images in a greenhouse. Detection results were compared with other adaptive segmentation algorithms. Values of F measuring precision and recall score were higher for the proposed multifractal analysis (96.5%) compared with conventional methods such as Watershed (92.2%) and Otsu (73.1%). The true positive rate of multifractal analysis was 94.3% and the false positive rate minimal level at 1.3%. Detection performance was further tested via human observation. The degree of scattering between manual and automatic counting was remarkably higher with multifractal analysis (R2 = 0.992) compared with Watershed (R2 = 0.895) and Otsu (R2 = 0.353), ensuring overall detection of the small-size pests is most feasible with multifractal analysis in field conditions. © 2012 Society of Photo-Optical Instrumentation Engineers (SPIE).

Xia C.,Pusan National University | Xia C.,CAS Yantai Institute of Coastal Zone Research | Lee J.-M.,Pusan National University | Li Y.,Pusan National University | And 3 more authors.
Biosystems Engineering | Year: 2013

We propose an in situ detection method of multiple leaves with overlapping and occlusion in greenhouse conditions. Initially a multilayer perceptron (MLP) is used to classify partial boundary images of pepper leaves. After the partial leaf boundary detection, active shape models (ASMs) are subsequently built to employ the images of entire leaves based on a priori knowledge using landmark. Two deformable models were developed with pepper leaves: Boundary-ASM and MLP-ASM. Matching processes are carried out by deforming the trained leaf models to fit real leaf images collected in the greenhouse. MLP-ASM detected 76.7 and 87.8% of overlapping and occluded pepper leaves respectively, while Boundary-ASM showed detection rates of 63.4 and 76.7%. The detection rates by the conventional ASM were 23.3 and 29.3%. The leaf models trained with pepper leaves were further tested with leaves of paprika, in the same family but with more complex shapes (e.g., holes and rolling). Although the overall detection rates were somewhat lower than those for pepper, the rates for the occluded and overlapping leaves of paprika were still higher with MLP-ASM (ranging from 60.4 to 76.7%) and Boundary-ASM (ranging from 50.5 to 63.3%) than using the conventional active shape model (from 21.6 to 30.0%). The modified active shape models with the boundary classifier could be an efficient means for detecting multiple leaves in field conditions. © 2013 IAgrE.

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