• Korean journal of applied entomology
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• v.22 no.2 s.55
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• pp.52-66
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• 1983

The brown planthopper, N. lugens (Stal), has become a serious pest of rice in tropical Asia during the last decade. At high pest density, its feeding damage causes 'hopperburn' or complete wilting and drying of the rice plant. It also transmits grassy and ragged stunt virus diseases. The estimated losses caused by the pest in tropical Asia exceed $US\$300$ millions. While cultivation of resistant rice varieties has proved to be highly effective against the pest, their long-term stability is threatened because of the evolution of prolific biotypes which can destroy these varieties. At present, identification of biotypes is based principally on the differential reactions of host rice varieties to the pest and on host-mediated behavioral and physiological responses of the pest. Recent findings of morphological differences in adult rostrum, legs, and antennae, body parts that possess receptors for host plant location and discrimination, and cytological differences in N. lugens populations maintained as stock cultures strongly complement other biotype studies. So far, three N. lugens biotypes have been identified in the Philippines. Biotype I can survive on and damage varieties that do not carry and genes for resistance, while Biotype 2 survives on resistant varieties carrying Bph 1 gene and Biotype 3 on varieties carrying gene bph 2. However, none of these biotypes can survive on varieties with genes Bph 3 or bph 4. Several varieties which are resistant in the Philippines are susceptible in India and Sri Lanka as the South Asian biotypes of N. lugens are more virulent than Southeast Asian biotypes. To monitor the pest biotypes in different geographical regions and to identify new sources of resistance, an International Brown Planthopper Nursery has been established in many cooperating countries. The evolution of biotypes is an exceedingly complex process which is governed by the interactions of genetic and biological factors of the pest populations and the genetic makeup of the cultivated varieties. While the strategy for sequential release of varieties with major resistance genes has been fairly successful so far, the monegenic resistance of these varieties makes them vulnerable to the development of the pest biotypes. Therefore, present breeding endeavors envisage utilizing both major and minor resistance genes for effective control of the pest.

• Mycobiology
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• v.32 no.1
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• pp.1-5
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• 2004

The present study was carried out to investigate morphological characteristics of pseudosclerotia of Grifola umbellata formed by artificial cultures. Isolate G. umbellata DUM GUS-01 was obtained from sclerotium cultivated in field. The fungal isolate was cultured on PDYM broth, PDYMA(potato dextrose yeast malt agar) and oak sawdust media at $20^{\circ}C$ under the dark condition. G. umbellata DUM GUS-01 showed a volumetric increment of fungal lumps rather than mycelial growth. Particularly, G. umbellata DUM GUS-01 produced a large amount of melanin pigments in all culture treatments. The color of the fungal mass has been changed into grey gradually, and then formed melanized rind-like structure on its superficial part. The fungal structures which were covered with melanized rind-like layer were named as pseudosclerotia of G. umbellata. The pseudosclerotia of G. umbellata DUM GUS-01 formed a new white mycelial mass, which was swollen out of the melanized rind structure for its volumetric increment. When the pseudosclerotia were sectioned, their structure was discriminated from two structures such as a melanized rind-like structure layer formed by aggregation of aged mycelia and a white mycelial mass with high density. As results of scanning electron microscopic examination, the pseudosclerotia of G. umbellata DUM GUS-01 which were formed in in vitro conditions were similar to the sclerotia of G. umbellata cultivated in natural conditions except for the crystals formed in medula layer of natural sclerotia. Although size, solidity of rind structure and mycelial compactness of pseudosclerotia were more poor than those of natural sclerotia, the morphological structure and growth pattern of pseudosclerotia were very similar to those of natural sclerotia. Therefore, it is probable to induce pseudosclerotia to sclerotia of G. umbellata in in vitro conditions. Consequently, it seems that the induced pseudosclerotia can be used as inoculum sources to substitute natural sclerotia in field cultivation.

• Journal of Mushroom
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• v.5 no.1
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• pp.13-20
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• 2007

Analysis of genetic characteristics of Flammulina velutipes showed that strains have a range of 85% in genetic distribution diagram. According to this result, we divided these strains into five groups. In experiment of determinating the optimum media and condition in cultivating F. velutipes, we found the optimum temperature and pH range for hypha growth were $25^{\circ}C$ and 6.0 to 7.0, respectively. in addition, the best media for growth of that in plate was MCM (Mushroom Complete Media) which have a growth length from 68 to 83 mm. In vivo test, we observed that fast growth and good density of hyphae in mixture media of douglas fir sawdust, cotton seed meal and beet pulp (6:2:2 V/V). Also when we cultivated F. velutipes in this media, we harvested high yield of fruiting body.

• Journal of Mushroom
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• v.14 no.4
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• pp.249-252
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• 2016

Timing, place, and the high-tech industry to overcome barriers to the introduct of the so-called "smart agriculture". The core factors of precision agriculture, including temperature, humidity, location information, and real summary information, are all significant for ICT controlling technique. The system is a four-season container allowing mushroom product, humidity, illumination, and factors such as carbon dioxide were regulated to create the optimal environment for mushroom cultivation. Hericium erinaceum (also called Lion's Mane Mushroom, Bearded Tooth Mushroom, or Bearded Tooth Fungus) is an edible and medicinal mushroom in the tooth fungus group. During approximately 40 days of incubation, 1.4 kg of oak sawdust was used as the test medium. The humidity, temperature, and $CO_2$ density were maintained at >85-95%, $18-20^{\circ}C$, and 700-1,000 ppm, respectively, in the container type culture system. The time for primordium formation was observed to be 4-7 days. The amount of fruitbody production was 74-95 g per bag. This technique will be used to establish a new community support program, in conjunction with international movement, domestic sales and exports are also planned.

• Journal of Bio-Environment Control
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• v.19 no.4
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• pp.333-342
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• 2010

For the energy-saving production of fresh vegetables in poor environment such as the Antarctic, a container-type plant factory was designed and developed. To maximize space usage of the 20 feet container ($L5.9m{\times}W2.4m{\times}H2.4m$), a three-level hydroponic cultivation system was installed and the nutrient solution was supplied by bottom watering. Using this system, 3 lettuce cultivars were grown under different the light source (light intensity). After 2 weeks from the transplanting, fluorescent lamp ($145\;{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$) showed the best fresh weight of top part and leaf area. However, After 4 weeks, fluorescent lamp plus metal halide lamp ($150\;{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$) led to the optimum growth of the each lettuce cultivar. The cultivar, 'Cheongchima', showed the best fresh weight of top part and leaf area, followed by 'Jeokchukmyeon' and 'Lollo rosa'. The chlorophyll concentrations (SPAD) showed no significant difference among the sources of lights. However, 'Cheongchima' showed relatively high chlorophyll concentration. With the above results, we found that the growth of lettuce is depend on light intensity and even at same intensity, the growth is different among the cultivars. Therefore, the selection of optimum cultivar should be considered in the plant factory system that has only weak light density.

• Journal of Mushroom
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• v.6 no.2
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• pp.43-46
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• 2008

This study was carried out to investigate the utilization of platanus for Pleurotus ostreatus culture medium. The results are as follows ; The growth of mycelial was the highest in the mixture medium of platanus sawdust 90% with rice bran 10% as of 12.8cm after 30days culture. The mycelia density of most of media were high exception of mixture medium, platanus tree sawdust 60% with rice bran 40%. The total nitrogen, phosphate, and potassium contents in all mushroom media were tended to decrease after oyster mushroom growth. In platanus sawdust 90% with rice bran 10%, total nitrogen, potassium, calcium and magnesium content of fruit body were higher than other treatments, but phosphate content was the highest in Douglas-fir sawdust 80% with rice bran 20% treatment as of 0.92%. The mycelial culture period was ranged 26~37 days according to different media, the mushroom yield of culture medium with platanus tree sawdust 80% with rice bran 20% was increased 18% compare to control Douglas-fir sawdust 80% with rice bran 20%.

• Journal of Mushroom
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• v.18 no.3
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• pp.274-279
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• 2020

This study was conducted to investigate the characteristics of the medium used on the composting step, comparing the excavator agitator with the self-propelled turner. The temperature of the outdoor composting medium tended to increase rapidly after flipping in the turner. The late composting medium temperature was maintained at the excavator treatment area (farm practice), and the late composting effect progressed. During the field composting stage, various microorganisms such as Bacillus spp., Actinomycetes, fluorescent Pseudomonas spp., and filamentous fungi were distributed in the medium, and the density of aerobic bacteria involved in the decomposition of the medium was increased. Under high-temperature composting conditions, blue fungi, and mesophilic actinomycetes were inhibited or killed. Thermophilic actinomycetes, which play an important role in decomposing organic matter, showed higher densities than those observed in farm practices in the self-propelled turner process. The length of rice straw was slightly shorter when the self-propelled turner was used, and the water content did not show any significant difference between treatments. The a and b values tended to increase as the inverter was turned over. The CN ratio of the composting broth was lowered from 23.1 to 16.2 for the 5th turnover in the context of farming practices, and from 23.3 to 16.9 in the context of the self-propelled turner. The yield of each treatment was increased by 20% in 1 period, 28% in 2 periods, and 26% in 3 periods; the overall yield was 23%.

• Research in Plant Disease
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• v.11 no.2
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• pp.158-161
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• 2005

Stenotrophomonas maltophilia BW-13 is a potent biocontrol agent to control crisphead lettuce bottom rot caused by Rhizoctonia solani. To define the optimum conditions for the mass production of the S. maltophilia BW-13, we have investigated optimum culture conditions and effects of various carbon sources on the bacterial growth. The optimum initial pH and temperature were determined as pH $6.0\~7.0 and $35^{\circ}C$, respectively. For the selection of effective carbon source for the mass production, we tested the low molecular carbon sources such as sucrose, glucose, lactose, maltose, manose and the high molecular carbon source such as dough conditioner, rice bran, corn starch, sweet potato starch. As the results, the addition of dough conditioner in a basal medium ($1.25\%\;K_{2}HPO_4,\;0.38\%\;KH_{2}PO_4,\;0.01\%\;MgSO_4{\cdot}7H_{2}O,\;0.5\%\;Yeast extract$) was able to achieve higher cell density and the antifungal activity than others. Therefore, the basal medium containing $3\%$ dough conditioner (named as dough conditioner medium) was finally selected the optimized media for the mass production of BW-13 strain.

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

• Weed & Turfgrass Science
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• v.5 no.4
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• pp.230-235
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• 2016

Miscanthus are perennial rhizomatous grasses and considered as an ideal cellulosic bioenergy crop. Recently, it was reported that Miscanthus was damaged by the larvae of rice stem borer, Chilo suppressalis Walker, one of the most destructive pests of rice in Korea since the 1960s. This study was thus conducted to evaluate the insecticidal effects against rice stem borer in the Miscanthus cultivation fields for two years. The experiment consisted of four chemical agent plots, one environment-friendly agent plot, and untreated plot. Untreated plot showed significantly high damage of 50%, while Buprofezin Tebufenozide and Carbosulfan Methoxyfenozide treatment plots showed low damage rate of 2% with low larvae density of 1 and $2.3larvae\;m^{-2}$, respectively. Damage rates of Tebufenozide, ChlorantraniliproleIndoxacarb, and environment-friendly agent(MatrineWood vinegar solution) were 15, 26, and 18%, respectively, which were lower than that of untreated plot but higher than those of Buprofezin Tebufenozide and Carbosulfan Methoxyfenozide. In conclusion, rice insecticides were effective against rice stem borer in Miscanthus field. In particular, the treatments with Buprofezin Tebufenozide and Carbosulfan Methoxyfenozide showed excellent control effects with control value of 93.3 and 95.2. However, further studies with different types of insecticides should be carried out for the selection of insecticides with more effective control of rice stem borer.