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Suigen, South Korea

Hong T.-K.,Seoul National University | Kim S.-I.,Seoul National University | Heo J.-W.,NaturoBioTech Co. | Lee J.-K.,South Korean National Institute of Animal Science | And 2 more authors.
Nematology | Year: 2011

The toxicity of Kaempferia galanga rhizome constituents to second-stage juveniles (J2) and eggs of Meloidogyne incognita was examined in vitro and in container experiments. Results were compared with those of three nematicides: carbofuran, fosthiazate and metam sodium. Ethyl cinnamate (EC) and ethyl p-methoxycinnamate (EMC) were the nematicidal and hatch inhibitory principles. In direct-contact mortality bioassays, EC 0.037 mg ml-1) and EMC (0.041 mg ml-1) were more toxic than carbofuran (0.092 mg ml -1) but less toxic than fosthiazate (0.002 mg ml-1) towards J2 based upon 48 h LC50 values. EC and EMC treatments resulted in 100% and 93 and 81% inhibition of hatch at 125.0 and 62.5 μg ml-1, respectively. Inhibition of these compounds was higher than carbofuran and metam sodium but significantly lower than fosthiazate. In contact +fumigant mortality bioassays with J2, EC and EMC applied at 0.25 and 0.125 mg (g soil)-1resulted in 81 and 80% and 77 and 73% mortality, respectively, while carbofuran and metam sodium treatments resulted in 86 and 96% and 57 and 73% mortality, respectively. Fosthiazate resulted in 92% mortality at 0.063 mg (g soil)-1. In vapour-phase mortality bioassays with J2, EC and EMC were more effective in a closed container than in an open one, indicating that mode of delivery was, in part, a result of vapour action. Global efforts to reduce the level of highly toxic synthetic nematicides in the agricultural environment justify further studies on K. galanga rhizome-derived materials, particularly ethyl cinnamate and ethyl p-methoxycinnamate, as potential nematicides and hatching inhibitors for the control of M. incognita as fumigants with contact action. © 2011 BRILL. Source


Chae S.-H.,Seoul National University | Kim S.-I.,Seoul National University | Yeon S.-H.,NaturoBioTech Co. | Lee S.-W.,South Korean National Institute of Animal Science | Ahn Y.-J.,Seoul National University
Journal of Agricultural and Food Chemistry | Year: 2011

The residual contact toxicity of three benzofuranoids (Z)- butylidenephthalide (1), (3S)-butylphthalide (2), and (Z)-ligustilide (3) identified in the rhizome of Cnidium officinale (Apiaceae) to B- and Q-biotype females of Bemisia tabaci was evaluated using a leaf-dip bioassay. Results were compared with those of eight conventional insecticides. Based on 24 h LC 50 values, (Z)-butylidenephthalide (254 ppm) and (Z)-ligustilide (268 ppm) were more toxic than (3S)-butylphthalide (339 ppm) against B-biotype females, whereas (Z)-ligustilide (254 ppm) and (3S)-butylphthalide (338 ppm) were more toxic than (Z)-butylidenephthalide (586 ppm) against Q-biotype females. Thiamethoxam, imidacloprid, and acetamiprid differ significantly in toxicity between the B- and Q-biotype females (LC 50, 1.7 to 11.6 vs 364.5 to >3000 ppm). This original finding indicates that the phthalides and the neonicotinoids do not share a common mode of action or elicit cross-resistance. Structure-activity relationship indicates that the presence of conjugation rather than aromaticity appeared to play an important role for phthalide toxicities to the B-biotype females. Global efforts to reduce the level of highly toxic synthetic insecticides in the agricultural environment justify further studies on C. officinale rhizome-derived materials as potential insecticides for the control of B. tabaci populations. © 2011 American Chemical Society. Source


Han J.,Seoul National University | Choi B.-R.,Seoul National University | Choi B.-R.,South Korean National Institute of Animal Science | Lee S.-G.,Seoul National University | And 4 more authors.
Journal of Economic Entomology | Year: 2010

The toxicity of 10 plant essential oils to adults of acaricide-susceptible, chlorfenapyrresistant (CRT-53), fenpropathrin-resistant (FRT-53), pyridaben-resistant (PRT-53), and abamectinresistant (ART-53) strains of Tetranychus urticae Koch (Acari: Tetranychidae) and to female Neoseiulus californicus McGregor (Acari: Phytoseiidae) was examined using spray or vapor-phase mortality bioassays. In bioassay with the susceptible adults, lemon eucalyptus (19.3 g/cm3) was the most toxic oil, followed by peppermint, citronella Java, thyme red, caraway seed, clove leaf, and pennyroyal oils (LC50, 20.623.7 g/cm3). The toxicity of these oils was almost identical against adults from either of the susceptible and resistant strains, even though CRT-53, FRT-53, PRT-53, and ART-53 adults exhibited high levels of resistance to chlorfenapyr (resistance ratio [RR], >9,140), fenpropathrin (RR, 94), pyridaben (RR, >390), and abamectin (RR, 85), respectively, Against female N. californicus, lemon eucalyptus (LC50, 21.4 g/cm3) was the most toxic oil, whereas the LC50 values of the other nine oils ranged from 23.2 to 72.6 g/cm3. N. californicus was 12 times more tolerant than T. urticae to the test essential oils. Thus, these essential oils merit further study as potential acaricides for the control of acaricide-resistant T. urticae populations as fumigants. © 2010 Entomological Society of America. Source


Trademark
Naturobiotech Co. | Date: 2003-12-23

Pesticides for industrial, commercial and domestic use, used especially for acarid; insect repellent; insecticides for industrial, commercial and domestic use; fungicides for commercial and domestic use; algaecides for commercial and domestic use; deodorants for other than human use, namely, air deodorant; allergy medications, namely nasal spray.


Hong T.-K.,Seoul National University | Lee J.-K.,South Korean National Institute of Animal Science | Heo J.-W.,NaturoBioTech Co. | Kim S.-I.,Seoul National University | And 2 more authors.
Nematology | Year: 2010

The toxicity of Kaempferia galanga rhizome-derived methanol extract (RME), powder (RP) and steam distillate (RSD) to Meloidogyne incognita second-stage juveniles (J2) and eggs, and their effects on Lycopersicon esculentum germination and growth were examined in vitro and in pot experiments. Results were compared with those of three nematicides: carbofuran, fosthiazate and metam sodium. In contact + fumigant bioassays with J2, RME applied at 1, 0.5 and 0.25 mg (g soil)-1 resulted in 92, 88 and 73% mortality, respectively. The lethality of RME was almost the same as carbofuran but lower than that of either fosthiazate or metam sodium. RSD and RP were less active than RME. In vapour-phase mortality bioassays with J2, the test materials were more effective in a closed container than in an open one, indicating that mode of delivery was, in part, a result of vapour action. In direct-contact mortality bioassays with M. incognita eggs, RME, RSD and fosthiazate treatments resulted in 91, 100 and 95% inhibition of hatch at 250 μg ml-1 and 82, 88 and 81% inhibition of hatch at 100 μg ml-1, respectively. In filter paper bioassays with L. esculentum seed, 8.8 μg cm-2 RME and RP did not cause germination inhibition, while RSD and fosthiazate treatments resulted in 84 and 13% germination inhibition. In pot tests, RME and RSD applied at 8 mg (g soil)-1 reduced galling caused by M. incognita significantly, and fosthiazate at 0.02 mg (g soil)-1 stopped galling completely. Kaempferia galanga rhizome-derived materials, particularly a methanol extract, merit further study as potential nematicides and hatching inhibitors for the control of M. incognita as fumigants with contact action. © Koninklijke Brill NV, Leiden, 2010. Source

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