• Journal of Bio-Environment Control
• /
• v.19 no.3
• /
• pp.147-152
• /
• 2010

Poor fruit set during winter period is one of the biggest problem in plastic tunnel watermelon cultivation. Hand pollination is inevitable to maximize fruit set of the winter watermelon. Productivity and viability of pollen grain and organic solvents for pollen storage were investigated. All cultivars produced more than 10 mg/flower except for 'Kumchun' cultivar. Pollen amount per flower were 13.8 mg in 'Bok' and 12.1 mg in 'Speedkul'. Germination rate of pollen grains incubated at $30^{\circ}C$ right after soaking in pentane solvent were 76% in 'Kumchun' as the lowest and 92% in 'Apollokul' as the highest. The pollen of 'Bok' showed the highest germination rate by 75% after a 15-day storage in pentane. All cultivars showed their pollen germination rate below 25% after a 24-day storage. Among the cuitivars, speed of pollen tube growth in vitro were relatively lower in 'Kumchun' and 'Sambokkul' by below $50\;{\mu}m/hr$. Pollen tube of these cultivars tended to burst during its elongation on the medium. Pollen stored 24 hrs in organic solvents showed 45, 39, 34, 23, and 19% of germination in pentane, ethyl ether, n-hexane, ethyl acetate, and acetone, respectively. Compared with light condition, pollen viability was higher in darkness during pollen storage in organic solvents. Pollen grain was susceptible to the organic solvent. The viability of pollen grains seems to be influenced greatly by duration of soaking pollen in organic solvent and the polarity of solvents. Organic solvent damages surface of pollen grain and extent of damage was varied by the solvents.

• Journal of the Korea Organic Resources Recycling Association
• /
• v.8 no.4
• /
• pp.100-110
• /
• 2000

Studies were conducted to know effects of the bulking agents (saw dusts, mushroom waste, wheat bran coconut meal, rice hulls) adding o moisture control, fermentation methods (aerobic and anaerobic) and periods (1 to 20 days) of food waste fermentation for animal feeds on chemical compositions and in vitro DDM (digestibility of dry matter). Experiment designs were focussed basically to obtain extension service data. The NDF (neutral detergent fiber) composition in the oak and pine saw dust were 93.5% and 95.4% (DM basis) in respectively. Thus, the fermented food waste feeds using saw dust (50%) increased NDF(12%), and decreased in vitro DDM(48%) compared to those of raw materials before aerobic fermentation. The oak saw dust showed higher DDM compared to pine. Mushroom wastes which is a residues of mushroom culture mixed originally willow saw dust (80%) and wheat bran (20%) showed quite higher feed value compared to both saw dusts. It was found that an in vitro DDM and NDF composition in fermented feeds appeared highly dependent or the NDF composition in bulking agents. With an increase wheat bran ratio substitute mushroom waste showed linearly decreased NDF, and increased in vitro DDM in the fermented food waste feeds. The fermented feeds added bottling agents composed higher NDF resulted in higher NDF and lower in vitro DDM with prolonged fermentation time. The feeds from anaerobic fermentation appeared lower NDF and higher in vitro DDM compared to those of aerobic fermentation.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.20 no.4
• /
• pp.308-316
• /
• 1987

The flying fish, Prognichthys agoo, is widely distributed in the coastal waters of south-eastern Korea. On July 14, 1986, mature adults of flying fish were captured from U-do, Cheju-do. The eggs were stripped and fertilized by the wet method on the ship. The mature eggs are demersal and adhesive with 30-40 filaments. The egg diameter varied from 1.42 to 1.58 mm. The water temperature throughout incubation ranged from 23.70 to $27.82^{\circ}C$, and salinity was maintained at $30.75-33.76\%_{\circ}$. The hatching took place in 174 hours after fertilization. The newly hatched larvae measured 4.75-5.25 mm in total length possessing yolk sac and about 45-46 myotomes. The larvae cultured for ten days after hatching reached 11.45-12.60 mm in total length and entered the juvenile period of life. Twenty days after hatching, the juveniles measured 20.01 mm in mean total length, and the scales were formed behind the pectoral fin.

• Research in Plant Disease
• /
• v.16 no.2
• /
• pp.129-135
• /
• 2010

PCR primers were developed to detect Pseudomonas savastanoi pv. phaseolicola, a causal agent of halo blight that occurs in all species of common bean (Phaseolus vulgaris L.), from the bean seeds. A primer set, Psp-JHF and Psp-JH-R, specifically amplified 513 bp fragment from Pseudomonas savastanoi pv. phaseolicola only. A nested primer set, psp-JH-F-ne and psp-JH-R-ne, designed from the $1^{st}$ PCR amplicon, amplified 169 bp fragment. The primer sets did not amplify any non-specific DNA from the seed extracts of Fabaceae including 4 beans, 2 soybeans, and 2 peas. The detection sensitivity of the nested PCR method developed in this study was much higher than that of ELISA and selective medium. PCR assays developed in this study should be useful to detect Pseudomonas savastanoi pv. phasolicola from the bean seeds.

• Journal of Plant Biotechnology
• /
• v.40 no.3
• /
• pp.147-155
• /
• 2013

In this experiment, we report for the first time mass propagation by in vitro mircrotuberization of Codonopsis lanceolata. We first examined the effect of cytokinins on multiple shoot induction. 2.0 $mg{\cdot}L^{-1}$ of kinetin not only gave the highest rate of shoot induction (19.1%) but also the elongation of shoot (17.1 mm). Secondly, we investigated the effect of sugars on in vitro microtuberization from nodal segments. The diameter of tuberous roots was enlarged in the half-strength MS medium supplemented with 145.9 mM sucrose. Histological analysis revealed that the number of parenchymatous cell containing starch grains increased in the tuberous roots. In addition, unlike in non-tuberous root, vascular bundles were scattered inner cortex layer. Thirdly, in order to preserve and stimulate the germination, microtubers were stored at $4^{\circ}C$ refrigerator during 9 months and then transplanted to the artificial soils (vermiculrite : peatmoss = 1:1 v/v), resulting that the rates of survival and germination were 75% and 70%, respectively. These results indicated that mass propagation of C. lanceolata was achieved by in vitro microtuber formation, suggesting that this protocol might be applied for not only the propagation of elite clones but also conservation of C. lanceolata germplasm.

• Weed & Turfgrass Science
• /
• v.4 no.1
• /
• pp.58-64
• /
• 2015

The black cutworm, Agrotis ipsilon (Hufnagel) is a major insect pest of economic crops including turfgrasses on golf courses. The entomopathogenic nematode, Steinernema carpocapsae GSN1 strain (ScG), a Korean isolate, is an effective biological control agent for soil dwelling and greenhouse insect pests in Korea. In addition, ScG is commercially produced in Korea. We conducted laboratory, greenhouse, and field trials to evaluate efficacy of ScG against black cutworms in turfgrasses. A rate of 63 infective juveniles (Ijs) per larva killed >90% of $3^{rd}$ instars feeding in cups of artificial diet within 3 days. In greenhouse trials against cutworms feeding in pots of turfgrass, efficacy of ScG was higher against $4^{th}$ instars than against $2^{nd}$ instars (90.0 vs 81.2% mortality, respectively, at $2,000Ijs\;pot^{-1}$) in perennial ryegrass, and higher against $3^{rd}$ instars in creeping bentgrass, Agrostis palustris than in zoysiagrass, Zoysia japonica (96.7 vs 52.5% mortality at $100,000Ijs\;m^{-2}$) in pot. The corrected mortality of $4^{th}$ instar was 79.9% at the rate of $100,000Ijs\;m^{-2}$ in the creeping bentgrass in the field. So ScG could be used as biological control agent against black cutworm in turfgrass of golf courses.

• Journal of Mushroom
• /
• v.13 no.3
• /
• pp.151-156
• /
• 2015

Cordyceps militaris is being studied and cultivated as a medicinal mushroom having many valuable biological and pharmaceutical activities. In the breeding of new C. militaris mushroom, single ascospores were isolated and examined their mycelial growth, mycelial density, and production of stroma and perithecia. Among them selected isolates were crossed and hybrids were produced showing high quality fruiting bodies on artificial media. Mycelial growth rate of new strain 'Dowonhongcho' was higher than that of better on 'Yedang 3' on SDAY at $10-25^{\circ}C$. The stromata of new strain were club-shaped and bright orange-red. Its height was 6.1 cm and the cordycepin content was 0.34% on average. The new strain showed 9% higher yield than 'Yedang 3' with producing firmer fruit bodies. The optimum temperature for mycelial growth was $22{\sim}25^{\circ}C$ and the optimum temperature for stroma development was $18{\sim}22^{\circ}C$. Fruiting bodies were began to produce 45 days later after inoculation. This new cultivar may serve as a valuable one for artificial cultivation and industrial-scale production of C. militaris.

• Journal of Mushroom
• /
• v.9 no.2
• /
• pp.63-68
• /
• 2011

Artificial cultivation of Lyopyllun decastes is costly because the high expense is required for soil covering and bark. Therefore, most farmers of Lyopyllun decastes have recognized it is difficult to cultivate it. The purpose of this study is to reduce the cost of cultivation of Lyopyllun decastes by applying new cultivation method and introducing mutation of fungi. In this study, a new method of practical artificial cultivation was developed through many experiments using fermented pine sawdust and wheat bran. In conclusion, the method of practical artificial cultivation of Lyopyllun decaste is simple and cost efficient because neither soil covering nor bark is required.

• Korean Journal of Microbiology
• /
• v.52 no.3
• /
• pp.352-364
• /
• 2016

In this study, we examined in vitro the potential probiotic properties of lactic acid bacteria (LAB) obtained from the fish intestine and their ability to degrade histamine through the production of diamine oxidase (DAO) enzymes and bacteriocin. Among 97 LAB strains isolated from the intestine of croaker, flatfish, pollack, and rockfish, CIL08, CIL16, FIL20, FIL31, PIL45, PIL49, PIL52, and RIL60 isolates exhibited excellent survival rates under simulated gastrointestinal tract conditions, high adhesion ability to HT-29 epithelial cells, and resistance to the antibiotics such as amoxicillin, ampicillin, erythromycin, penicillin G, streptomycin, tetracycline, or vancomycin. In addition, these strains did not produce histamine in decarboxylating broth containing histidine. In particular, 4 strains (CIL08, FIL20, PIL52, and RIL60) that may produce DAO were significantly able to degrade histamine. The bacteriocins produced by FIL20, FIL31, and PIL52 LAB inhibited the growth and histamine production of Enterococcus aerogenes CIH05, Serratia marcescens CIH09, Enterococcus faecalis FIH11, Pediococcus halophilus FIH15, Lactobacillus sakei PIH16, Enterococcus faecium PIH19, Leuconostoc mesenteroides RIH25, or Aeromonas hydrophilia RIH28. Histamine-producing strains isolated from fish intestine were found to reduce histamine accumulation during co-culture with CIL08, FIL20, PIL52, and RIL60 LAB showing histamine degradation or bacteriocin production ability. The probiotic strains preventing histamine formation were identified as Pediococcus pentosaceus CIL08, Lactobacillus plantarum FIL20, Lactobacillus paracasei FIL31, Lactobacillus sakei PIL52, and Leuconostoc mesenteroides RIL60 with high similarity based on 16S rRNA gene sequencing.

• The Korean Journal of Mycology
• /
• v.24 no.1 s.76
• /
• pp.67-80
• /
• 1996

Eleven fruit bodies of Ganoderma sp. were collected from eight locations throughout the forest of Kangwon province and Kyunggi province in Korea. The hosts in forest were cut trunks of Quercus dentata, Q. variabilis, Prunus peria and Alnus japonica that was newly surveyed but 5 isolates were collected at the farms of Ganoderma mushroom. Most fruit bodies were formed solitarily on the cut trunks but GS-106 isolate grown in crowds on cut trunk of Alnus japonica. Optimal temperature ranges for isolates of species studied were: G. applanatum $28^{\circ}C{\sim}30^{\circ}C$, G. lucidum $28{\sim}30^{\circ}C$, G. neo-japonicum $28^{\circ}C$, and G. tsuage $26^{\circ}C$ and all the species grew slowly at the $32^{\circ}C$. Hamada medium adjusted with pH 5.4 and 6.2 is better than other media for mycelial growth. Mycelial morphological characteristics of six species were studied: G. applanatum, G. lucidum and G. neo-japonicum produced typical type of staghoru hyphae but G. oregonens and G. valeosiacum produced staghoru hyphae with a branch of grape form. Clamp connection was observed on hypha of G. applanatum, G. lucidum, G. oregonense and G. valeosiacum except G. neo-japonicum with node type. Chlamydospore was produced by G. applanatum, G. neo-japonicum. and cuticular cells were present on hyphae of G. lucidum, G. neo-japonicum, G.oregonense and G. tsugae.