• The Korean Journal of Pesticide Science
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• v.15 no.3
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• pp.269-277
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• 2011

Recent outbreak of new diseases and pests which were introduced from abroad, seriously hampered both quality and safety of paprika fruits. This study has been carried out to aid an establishment of guideline for safe use of pesticides and reduction of their residues on paprika. Systemic fungicides boscalid and pyraclostrobin of either mixed (a.i.; 13.6+6.8%) or single (a.i.; 47 and 18.8%, respectively) water dispersible granule formulation(WG) products were sprayed with recommended or double dosage on paprika grown in green house at March and June. To draw pre-harvest residue limit, residues of each fungicide were analyzed from fruits collected eight times from 18 to 1 day pre-harvest. The biological half-lives of both boscalid and pyraclostrobin in mixed formulation in March and June were slightly shorter than those of single formulation which ranged from 14.4 to 20.1 days. Residue levels of both fungicides of single formulation in fruits in June were about one lower compared to those in March. However, application of double dosage frequently exceeded MRLs from fruits grown both seasons. These results showed that residue levels on fruits persisted longer period of time, more than two weeks, and so the case applied in winter season. The dissipation of fungicides on leaves and fruits was compared. The distribution of both fungicides in leaves was 20-200 times higher than that of fruits and persisted up to 18 days of pre-harvest period at the concentration of 10-40 ${\mu}g\;g^{-1}$. This study indicated that the mixed formulation product exhibited low residues in fruits, but high and long enough to pathogen growth in leaves.

• The Korean Journal of Pesticide Science
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• v.10 no.2
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• pp.76-83
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• 2006

In order to investigate the impacts of non-selective herbicide, glufosinate-ammonium (ammonium 4-[hydroxy(methyl)phosphinoyl] -DL-homoalaninate, GLA) to the non-target organisms, earthworm was exposed to GLA in the field soil for a month, and microbial populations in the soil were investigated after application of GLA. Simultaneously, the residues of GLA and its metabolite, 3-MPP were analyzed in the same soil. Meanwhile, to elucidate the influence of GLA to the growth of non-target crops incase of inter-furrow application, the amounts of carotenoid, chlorophyll, amino acid, proteins and sugars in the leaves of potato and chinese cabbage grown in the same field were investigated. In result, the dead earthworm was not observed during the test period, and the increasing rates of bodyweight were $9.410{\sim}11.603%$ in GLA-treated plots and 5.645% in GLA-untreated plots. The populations of fungi, bacteria and actinomycetes in the GLA-treated soils were $6.2{\times}10^4$, $1.5{\times}10^6$ and $5.7{\times}10^4$, respectively. They maintained relatively similar levels to the control which were $3.7{\times}10^4$, $3.7{\times}10^5$ and $3.7{\times}10^4$, respectively. In residue analysis, the limit of detection of GLA was 0.02 mg $kg^{-1}$, that of 3-MPP was the same level, and the half-life of GLA was 15 days in sandy clay loam soil. This result indicates that GLA was degraded very quickly in field soil. On the other hand, the amounts of physiological, biochemical components such as carotenoid, amino acid, chlorophyll, protein and sugar were ranged from 90.0 to 104.3% in potato and from 99.0 to 112.7% in chinese cabbage. Comparing with hand-weeded plots, it is indicated that GLA had not affected to the growth of non-target crops when applied at inter-furrow in crops-growing field.