• Korean Journal of Environmental Agriculture
• /
• v.28 no.3
• /
• pp.301-309
• /
• 2009

The use of bioactive materials derived from microorganisms and plants has played a role in pest management in environmentally-friendly agriculture (EFA) system. In Korea, a number of agricultural agents for the control of insect pests have been registered officially as biopesticides and marketed widely. However, most of the biopesticides has a limitation in the resource availability of bioactive materials, which has been one of main problems related to the commercialization of agricultural agents. Plant materials and microbial metabolites are the best sources as starting components to commercialize natural-occurring agricultural agents for pest management. The lack of modernized system for the standardization and quality control of the starting materials, however, has also received as a main problem related to the commercialization of agricultural agents. Considered that EFA business has kept growing bigger and bigger with global economic status, the commercialization of agricultural agents is necessary to meet the required number of agricultural agents officially available in EFA. This study describes the status and future prospects of pest control agents in EFA. A number of main issues hindered in the commercialization of agricultural agents are discussed in order to present a promising approach to successful commercialization.

• Korean Journal of Organic Agriculture
• /
• v.23 no.2
• /
• pp.347-357
• /
• 2015

This experiment was conducted to test the efficiency of environmentally friendly materials for controlling garlic leaf blight by Stemphylium botryosum. Fifty five kinds of environmental friendly control agents are obtained from commercial market and are tested for spore germination using 96 well plate and among them, five agents (copper-, sulfur-, medinal herb extract-, sulfur+sodium bicarbonate- and oligo chitosan based compound) are selected for field test from 2012 and 2013 year. With reference of 2012 year test result, copper and oligo chitosan based compounds are chosen as 2013 year test. When the first symptoms were appeared early May season and environmental friendly control agents are applied as prompt as possible, the control value of copper and oligo chitosan based agents are 54% and 90% respectively as compared to the occasion of chemical agent Antracol WP (propineb 70%) and yield of bulbs are increased by 16% and 34% against untreated control and marketable garlic bulb yield were 79% and 95% against Antracol WP treatment, respectively. From this result, oligo chitosan based compound can be a good organic control agent candidate for garlic leaf blight disease in organic garlic cultivation.

• Korean Journal of Environmental Agriculture
• /
• v.33 no.3
• /
• pp.184-188
• /
• 2014

BACKGROUND: White stain symptom caused by Acremonium acutatum and Trichothecium roseum, is one of the most important diseases on the grape. This disease occurs national-wide in Korea and causes irreversible damage on grape, at harvest season. This study was conducted to develop environment-friendly control method against white stain symptom. METHODS AND RESULTS: Environment-friendly materials were tested for control activity against A. acutatum and T. roseum in vitro and in vivo. The effect of environment-friendly materials against white stain symptom on grape in farmer's greenhouse was examined. The materials, NaDCC and sulphur, were sprayed three times on the leaves and fruit of grape at the two sites of farmer's field, Anseong and Hwaseong of Gyeounggi. To evaluate control effect of NaDCC and sulphur against white stain symptom, the disease severity was investigated after the two materials were sprayed from the disease onset three times at the 7-day intervals. NaDCC showed efficacy of 59.71% for Kyoho and 72.26% for Campbell-Early, and sulphur showed 78.31% for Koyho and 66.19% for Campbell-Early. CONCLUSION: We were selected sulphur and Sodium-Dichloroisocyannurate(NaDCC) based on the results of experiments in vitro. In field test, sulphur and NaDCC showed suppressive effect in the white stain symptom of grape. These results suggested that NaDCC and sulphur selected can be used as control agents for controlling white stain symptom on grape.

• Korean Journal of Soil Science and Fertilizer
• /
• v.44 no.2
• /
• pp.308-315
• /
• 2011

Ammonium- and potassium-loaded zeolite (NK-Z) and other four kinds of environmental friendly fertilizers/agents were applied to characterize their effectiveness on garlic (Allium sativum L.) growth and soil amelioration. Selenium dioxide ($SeO_2$) and germanium dioxide ($GeO_2$) liquid treatments significantly increased selenium (Se) and germanium (Ge) contents in garlic stems, garlic cloves and clove peels. In soil treated with ZBFC, Se contents in garlic stems, cloves, and clove peels was 13.89-, 12.79-, and 10.96-fold higher, respectively, than in the controls. The inorganic contents of plants grown in soil treated with functional strengthened fertilizers were also higher than in plants grown in control soil. Soil treated with arbuscular mycorrhizal fungi (AMF) agents exhibited significantly greater spore density and root colonization rate than in untreated soil. The density of chitinolytic microorganisms in soil treated with colloidal chitin was also significantly higher than in untreated soil. The cation exchange capacities (CEC) in ZAFC-, ZBFC-, and ZBF-treated soils was 16.05%, 8.95%, and 8.80% higher than in control soil 28 weeks after sowing.

• Research in Plant Disease
• /
• v.27 no.3
• /
• pp.91-98
• /
• 2021

The current social demand for organic, sustainable, and eco-friendly approaches for farming, while ensuring the health and productivity of crops is increasing rapidly. Biocontrol agents are applied to crops to ensure biological control of plant pathogens. Research on the biological control of white root rot disease caused by a soil-borne pathogen, Rosellinia necatrix, is limited in pears compared to that in apple and avocado. This pathogenic fungus has an extensive host range, and symptoms of this disease include rotting of roots, yellowing and falling of leaves, wilting, and finally tree death. The severity of the disease caused by R. necatrix, makes it the most harmful fungal pathogen infecting the economical fruit tree species, such as pears, and is one of the main limiting factors in pear farming, with devastating effects on plant health and yield. In addition to agronomic and cultural practices, growers use chemical treatments to control the disease. However, rising public concern about environmental pollution and harmful effects of chemicals in humans and animals has facilitated the search for novel and environmentally friendly disease control methods. This review will briefly summarize the current status of biocontrol agents, ecofriendly methods, and possible approaches to control disease in pear orchards.

• The Korean Journal of Pesticide Science
• /
• v.15 no.4
• /
• pp.479-484
• /
• 2011

The number of comstock mealybug, Pseudococcus comstocki (Kuwana) suddenly increased at ginseng fields in Yangpyeong, Gyeonggi-do from mid July to early August. By the late of September just before digging up the roots of ginseng, more than 8 individuals of the comstock mealybug per plant were occurred and evenly dispersed around the roots. Through the bioassay in the laboratory, six environmental friendly agricultural materials (for example, Nobug, Kkagsami, GB-1, GB-2, GB-3, GB-5) containing sophora extract or paraffin oil as main components were selected by the effective control agents for controlling the comstock mealybug. These selected agents showed a quite similar insecticidal activities to 2 insecticides such as clothianidin and thiamethoxam registered in control of ginseng insect pests. Also. in the ginseng field test, the agent containing sophora extract and paraffin oil, like 2 insecticides showed high control effects against the comstock mealybug.

• The Korean Journal of Pesticide Science
• /
• v.15 no.1
• /
• pp.55-60
• /
• 2011

To work out quality control methods of environmental-friendly organic materials (EFOMs), the reason and basis for EFOM-selection and farmer's favorite formulation type of EFOMs, etc were investigated on farmers who had been practicing environmental-friendly agriculture. EFOMs used were soil amendments, control agents of plant diseases and insect pests, plant growth promotion formulations, in turns. In EFOMs application time, 22.7% of farmers sprayed EFOMs without delay after they were bought, in other hand, 77.3% of farmers used EFOMs which had been bought and stored for some period. Microbial density on seventeen environmental-friendly microbial formulates (EFMFs) including microbial pesticides, a microbial fertilizer, and environmental-friendly organic materials was investigated at different storing temperature and shelf life. When the microbial density of EFMFs was investigated without delay after they were bought, all used microbial pesticides and a microbial fertilizer was confirmed to be optimal for the certified density but two of environmental-friendly organic materials was confirmed not to be optimal. When microbial density of 17 EFMFs were investigated after storing them for six months at $4^{\circ}C$, only one of 9 microbial pesticides was confirmed not to be optimal, the other hand four of seven environmental-friendly organic materials not to be optimal, which each of their microbial density was less than the certified density. Population dynamics of microbial agents was much more influenced in fluctuated temperature (room temperature) than in static temperature condition ($5^{\circ}C$ and $25^{\circ}C$). Shelf life of microbial agents according to microbial formulation type were high in granule type, liquid wettable type and liquid type in turns.

• Korean Journal of Organic Agriculture
• /
• v.20 no.1
• /
• pp.49-58
• /
• 2012

Greenhouse whitefly, $Trialeurodes$ $Vaporariorum$, is the most important insect pest in environmental friendly tomato production. Natural enemies, $Nesidiocoris$ $tenuis$ and environmental friendly agricultural materials (EFAM) are major control agents in Korea. The aim of the present work is to evaluate release time of $N.$ $tenuis$ in controlling of $T.$ $vaporariorum$ and to select environmental friendly agricultural materials (EFAM) to suppress both $T.$ $vaporariorum$ and $N.$ $tenuis$ which if the density were high causing necrotic rings. Six EFAM selected to control of $Trialeurodes$ $Vaporariorum$ in three times spray with seven days intervals. Three EFAM showed high mortality 67.7-70.5% in spray after release plot but low in release after spray plot. It should be careful to spray with $N.$ $tenuis$. When $N.$ $tenuis$ were early release at 7 days after transplanting which before occurring and establishment of greenhouse whitefly, it could suppress the density. Extracts of bead tree + matrin, matrin 1, Chrysanthemum showed high mortality on $T.$ $vaporariorum$ adults and $N.$ $tenuis$. The results suggested that this three EFAM could be control agents of the damage of necrotic rings from $N.$ $tenuis$.

• The Korean Journal of Pesticide Science
• /
• v.15 no.4
• /
• pp.471-478
• /
• 2011

The ginseng stem fungus gnat, Phytosciara procera, overwintered in old stems and roots of ginseng as a larvae from late September to early May in next year. In the late Spring they become pupa then emerged. Therefore, the first control period has to be set between late May and early June. It is a same period of elimination of ginseng flower stalks. Two or three times pest control might be needed per month for controlling adult of P. procera. Otherwise, the overwintered form as larva in old stem by removal of old stems of ginseng, the population of first generation of P. procera adults could be reduced. However, it seemed that the removal of old stems was not necessarily correlated with the population of P. procera adults in the next generation. Three kinds of environmental-friendly control agents that were mainly contained sophora extract, showed the highly insecticidal activities against larva of P. procera. Among them, one agent containing sophora extract and paraffin oil showed an ovicidal action as well as oviposition repellency.

• Research in Plant Disease
• /
• v.23 no.2
• /
• pp.89-98
• /
• 2017

Ralstonia solanacearum species complex (RSSC) causes bacterial wilt, and it is one of the most important soil-borne plant pathogenic bacteria. RSSC has a large host range of more than 50 botanical families, which represent more than 200 plant species, including tomato. It is difficult to control bacterial wilt due to following reasons: the bacterial wilt pathogen can grow inside the plant tissue, and it can also survive in soil for a long period; moreover, it has a wide host range and biological diversity. In most previous studies, scientists have focused on developing biological control agents, such as antagonistic microorganisms and botanical materials. However, biocontrol attempts are not successful. Plant-derived metabolites and extracts have been promising candidates to environmentally friendly control bacterial wilt diseases. Therefore, we review the plant extracts, essential oils, and secondary metabolites that show potent in vivo antibacterial activities (in potted plants or in field) against tomato bacterial wilt, which is caused by RSSC.