• International Journal of Industrial Entomology and Biomaterials
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• v.38 no.2
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• pp.31-37
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• 2019

Silkworm larval mortality specifically during spinning stage leading to non-spinning with specific morphological symptoms was frequently complained by sericulturists in Karnataka, India during 2015. Survey was conducted and information collected through questionnaire from the identified farmers who faced the problem of non-spinning in both traditional and non-traditional areas of Karnataka. Survey results indicate that the problem is specific to the silkworm crop of those farmers' who shifted from other crops of agriculture/ horticulture/olericulture/ floriculture to Sericulture. Silkworm rearing performance of the batches fed with these leaves confirmed that the pesticide sprayed to the crops previous to mulberry, remain in the soil and when mulberry plantation is taken up in these gardens, the pesticide is absorbed by the roots of mulberry plants and transported to the leaves. Silkworms that feed on these mulberry leaves, grow and ripen normally but during spinning stage, larvae die with external symptoms like regurgitation, body shrinkage, rectal protrusion later become hook shaped leading to non-spinning or partial metamorphosis into pupa and death or spin flimsy cocoons. Larval mortality ranged from a minimum of twenty five percent to a maximum of hundred percent. The problem was noticed from the first harvest of leaves and lasted for a maximum period of 36 months. Cocoon crop loss depends on the concentration, duration and type of pesticides used previously for other crops.

• Journal of Practical Agriculture & Fisheries Research
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• v.11 no.1
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• pp.21-33
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• 2009

The agricultural tourism is something that urban people can have an experience of the traditional culture and knowledge of the agriculture, so that it result the improvement of the agricultural profit and keep the special agricultural system. Recently, the demand of the agricultural tourism was increasing, but it was not really enough today that the practice of the tourism for essential farm experience or physical plan. The experiments were practiced by a land in Sucheong-li, Namjong-myun, Gwangju-si, Gyeonggi-do which provides the program for the basic plan and management of the experiential farm, so it shows a developmental model of that typical farm. The basic design of developmental model was formed by the analysis of the natural, civilized and visual environments. The site plan for the experiential farm was composed of a parking lot, public facilities, resting place, experiential site, sports facilities and pedestrian space. There was an examination that the activation of experiential farm should change the concept of the big production or labor-focused farm from a tourism-focused form.

• Korean Journal of Agricultural Science
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• v.50 no.2
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• pp.235-248
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• 2023

Orchidaceae species account for one-tenth of all angiosperms including more than 30,000 species having significant ecological, evolutionary, and economic importance. Despite Orchidaceae being one of the largest families among flowering plants, crucial cytogenetic information for studying species diversification, inferring phylogenetic relationships, and designing efficient breeding strategies is lacking, except for 10% or less of orchid species cases involving mostly chromosome number or karyotype analysis. Also, only approximately 1.5% of the identified orchid species from less than a hundred genera have genome size data that provide crucial information for breeders and molecular geneticists. Various molecular cytogenetic techniques, such as fluorescence in situ hybridization (FISH) and genomic in situ hybridization (GISH), have been developed for determining ploidy levels, analyzing karyotypes, and evaluating hybridity, in several ornamental crops including orchids. The estimation of genome size and the determination of nuclear DNA content using flow cytometry have also been employed in some Orchidaceae subfamilies. These different techniques have played an important role in supplementing beneficial knowledge for effective plant breeding programs and other related plant research. This review focused on orchid breeding summarizes the status of current cytogenetic tools in terms of background, advancements, different techniques, significant findings, and research challenges. Principal roles and applications of cytogenetics in orchid breeding as well as different ploidy level determination methods crucial for breeding are also discussed.

• Horticultural Science & Technology
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• v.17 no.3
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• pp.344-345
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• 1999

This experiment was conducted to investigate the effects of a growth retardant uniconazole treatment time on the growth and flowering of Cymbidium Pine Clash 'Moon Venus' and Cym. Green Sour 'A One' in order to develop a substitutional technique on the highland cultivation. Leaf growth of both cultivars was more remarkably reduced by earlier uniconazole treatment time and growth reduction of 'A One' was more remarkable than 'Moon Venus'. Flowering time of 'Moon Venus' treated with uniconazole at May 7 and 27 was accelerated by 5 and 6 days respectively. Moreover, the number of inflorescences and florets showed a tendency to increase. However there was no difference in flowering time of 'A One' among treatments but there was a tendency to decrease in the number of inflorescences and florets by uniconazole treatment. In both cultivars, there was no difference among treatments in the length and width of lower sepal which represent the floret size.

• The Plant Pathology Journal
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• v.16 no.4
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• pp.242-245
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• 2000

In 1999 and 2000, a rot of graft-cacti including Hylocereus trigonus (three-angled cactus), Gymnocalycium mihanovichii, and Chamaecereus silvestrii occurred in several greenhouses in major cactus-growing areas of Korea. Typical symptoms included a moist, light brown rot or a watery rot of the stems. A Colletotrichum sp. was isolated from the lesions. The fungus formed dark gray, dense or floccose colonies on potato dextrose agar, frequently forming many light pink acervuli often surrounded with setae. The hyaline, cylindrical conidia were one-celled with round ends. Appressoria were mostly semicircular or clavate. Thin-walled asci contained eight, one-celled, hyaline ascospores (biseriate in ascus). Ascopspores were strainht or curved, ellipsoidal or subcylindrical. Based on these characteristics, the fungus was identified as Glomerlla cingulata (anamorph : C. gloeosporioides). Wound inoculation of basal stems of the cactus by the mycelial plugs or conidia produced symptoms identical to those described above. Various cactus species were compared in susceptibility using stem disc inoculation. Cereus tetragonus, Eriocereus jusbertii, Myrtillocactus geomentrizans, and three-angled cacti from Mexico and Taiwan were susceptible, but C. peruvianus (Peruvian apple cactus) and Harrisia tortuosa not. This is the first report of G. cingulata causing stem rot of graft-cactus in Korea.

• Korean Journal of Environmental Agriculture
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• v.14 no.2
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• pp.246-249
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• 1995

This study was conducted to establish the optimal ratio of $NO_3^-$ and $NH_4^+$ for the nutrient culture of Gerbera hybrida Hort. The results were summarized as follows; 1. The growth of 'Volga' was best in 8 : 2($NO_3^-$ : $NH_4^+$) solution, while that of 'Mirage' was in 9 : 1 ratio. 2. The maximum quantity of cut flowers could be harvested in the 8 : 2 solution in 'Volga', whereas in 9: 1 solution in 'Mirage', but the differences between 9 : 1 and 8 : 2 were not significantly great. 3. In 'Volga', the qualities of cut flowers were not different among 10 : 0, 9 : 1 and 8 : 2, while those in 'Mirage' were not different among all treatments. 4. It turned out that the optimum ratio of $NO_3^-$ and $NH_4^+$ for the nutrient culture of gerbera in the farm house was 8 : 2, irrespective of cultivas.

• Korean Journal of Plant Resources
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• v.22 no.3
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• pp.236-241
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• 2009

Dracocephalum argunense Fischer ex Link (Labiatae) is a perennial herbaceous plant used as valuable materials for ornamentals, honey production, and pharmaceutics. Since seed germination of this species was quite difficult, present studies were conducted to improve the germination rate by subjecting the seeds to various environmental conditions (temperature and light) and treatments (scarification, priming and seed coating). Optimum temperature for adequate germination was 20$^{\circ}C$ though it ranged from 15$^{\circ}C$ to 25$^{\circ}C$, and low temperature treatment improved germination rate. Light was required for higher germination rate in this species. The scarification of seeds resulted in much higher germination, especially by the physical treatment with sandpaper or chemical treatment with sulfuric acid for 30 seconds. Various primers with different concentrations were treated on the seeds and it was demonstrated that low temperature enhanced germination rate, regardless of kinds and concentrations of the primers. Three treatment combinations of the primers, 0.5 mM $GA_{3}$ treated for 48 hours, 0.5 mM IAA for 24 hours, and 1.0 mM IAA for 24 hours, increased the seed germination rate profoundly. Soaking treatment of inorganic salts, $KNO_{3}$ and $KH_{3}PO_{4}$, promoted germination when seeds were subjected to low temperature. Water soluble primers such as sucrose at 0.5 and 3% concentration and solid primer talc powder were effective in enhancing germination rate.

• Korean Journal of Plant Resources
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• v.30 no.6
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• pp.699-706
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• 2017

For rapid production of freesia 'Shiny Gold' shoots by using a bioreactor, several culture conditions were investigated. Young shoots (< 1 cm) obtained from freesia corm section in vitro were used as plant materials for this experiment. As a basic experimental environment, 20 young shoots were inoculated into a 5 L balloon type bubble reactor which contained 1 L 1/2 strength MS medium supplemented with 30 g sucrose (3%), and the aeration was 0.1 vvm (vessel volumes per minute). The bioreactors were placed in a growth room with $23^{\circ}C$ temperature, 60% relative humidity and $60{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ light condition (16 h/8 h, day/night). The concentrations of MS media were set with 1/4, 1/2, 1 strength, medium volume 10, 20, 40%, sucrose concentration 3, 6, 9%, and aeration 0.1, 0.2, 0.4 vvm. After 4 weeks of cultivation, the growth indexes including the fresh and dry weight, and plant height were evaluated. At the same time, the consumption, pH, and EC of medium were estimated 4 weeks after incubating. The best results were achieved when 40 young shoots were incubated in a bioreactor in which 1 L of 1/2 strength MS medium supplemented with 6% sucrose was used for the rapid production of freesia shoots. The shoots were 17 cm in plant height and 1.0 g in fresh weight only 4 weeks after incubation which could be a good plant material suitable for corm enlargement in vitro. No correlation was observed between the growth of freesia shoots and the consumption, pH or EC of medium.

• The Plant Pathology Journal
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• v.22 no.2
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• pp.147-151
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• 2006

Disease incidences of cucumber virus diseases in Jeonnam province were 52.5%, 16.1%, 35.2%, and 50.9% in 1999, 2000, 2001, and 2002, respectively. Rod- and flexuous rod-shaped virus particles were observed with the frequencies of 63.2% and 10.5%, respectively from the samples collected in 1999 under EM observation. Rod-shaped virus particles are considered as tobamovirus while flexuous rod shaped particles are considered as potyviruses. To further confirm their nature, total of 312 diseased virus samples were collected from 2000 to 2002, and tested by RT-PCR. Disease incidences of tobamoviruses including Cucumber green mottle mosaic virus and Kyuri green mottle mosaic virus were 48.7% and 3.8%, respectively while those of potyviruses including Zucchini yellow mosaic virus, Papaya ringspot virus, and Watermelon mosaic virus were 15.7%, 9.3%, and 5.1%, respectively. Interestingly, Cucumber mosaic virus was hardly detected. About 5.8% of tested samples were infected with more than one virus. Tobamovirus infection was consistently observed from September to December regardless of planting time, whereas infection of potyviruses was observed in many cucumber cultivating areas where it was planted in September and October.

• Journal of Plant Biotechnology
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• v.46 no.4
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• pp.255-273
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• 2019

Orchids are indispensable to the floriculture industry due to their unique floral organization. The flowers have two outer whorls of tepals including a lip (labellum), and two inner whorls, pollinia and gynostemiun (column). The floral organization and development is controlled at the molecular level, mainly by the MADS-box gene family, comprising homeotic genes divided into type I and type II groups. The type I group has four sub-groups, Mα, Mβ, Mγ, and Mδ, playing roles in seed, embryo, and female reproductive organ development; the type II group genes form classes A, B, C, D, and E, which are a part of the MIKC^C subgroup with specific roles in florigenesis and organization. The coordinated functioning of these classes regulates the development of various floral whorls. The availability of genome and transcriptome sequence data for Phalaenopsis equestris offers an opportunity to validate the ABCDE model of flower development. Hence, this study sought to characterize the MADS-box gene family and elucidate of the ABCDE model. A total of 48 identified MADS-box proteins, including 20 type I [Mα (12), Mγ (8)] and 28 type II [MIKC^C (27), MIKC*(1)] members, were characterized for physico-chemical features and domains and motifs organization. The exon-intron distribution and the upstream cis-regulatory elements in the promoter regions of MADS-box genes were also analysed. The discrete pace of duplication events in type I and type II genes suggested differential evolutionary constraints between groups. The correlation of spatio-temporal expression pattern with the presence of specific cis-regulatory elements and putative protein-protein interaction within the different classes of MADS-box gene family endorse the ABCDE model of floral development.