TY - JOUR

T1 - Soil application of azadirachtin and 3-tigloyl-azadirachtol to control western flower thrips, Frankliniella occidentalis (Thysanoptera

T2 - Thripidae): Translocation and persistence in bean plants

AU - Thoeming, Gunda

AU - Draeger, Gerald

AU - Poehling, Hans Michael

N1 - Copyright: Copyright 2008 Elsevier B.V., All rights reserved.

PY - 2006/8

Y1 - 2006/8

N2 - To study the systemic effects of active neem ingredients, the substrate of bean plants was treated with a 170 g kg-1 azadirachtin (NeemAzal-U; Trifolio-M GmbH, Lahnau, Germany, registration pending). This product was used at a dose rate of 10 mg AZA (azadirachtin a) and 1.2 mg 3-tigloyl-azadirachtol (azadirachtin b) per treated bean plant. Afterwards, the translocation and persistence of AZA and 3-tigloyl-azadirachtol and the effects on western flower thrips, Frankliniella occidentalis (Pergande), were studied. Residues of AZA and 3-tigloyl-azadirachtol from substrates with different contents of organic matter [pure culture substrate (CS), CS-sand mixture] and from various plant parts were quantified by high-performance liquid chromatography-mass spectrometry (HPLC-MS). The dissipation trends of AZA and 3-tigloyl-azadirachtol were similar within the same substrates. A slower decline of both active ingredients was measured with CS than with CS-sand mixture. Residue analysis of the bean plants showed that only small proportions of the initial amounts of AZA and 3-tigloyl-azadirachtol applied to the substrate were present in the plant (0.3-8.1%). Variable amounts of residues of the active components in relation to plant parts and time of analysis indicated a different translocation pattern for the two active ingredients. Higher residues of the active ingredients were found in roots and stems after neem application using CS, whereas higher residues were found in leaves after CS-sand mixture treatments. Mortality of F. occidentalis after NeemAzal-U soil applications reached up to 95% on CS-sand mixture, compared with 86% in CS.

AB - To study the systemic effects of active neem ingredients, the substrate of bean plants was treated with a 170 g kg-1 azadirachtin (NeemAzal-U; Trifolio-M GmbH, Lahnau, Germany, registration pending). This product was used at a dose rate of 10 mg AZA (azadirachtin a) and 1.2 mg 3-tigloyl-azadirachtol (azadirachtin b) per treated bean plant. Afterwards, the translocation and persistence of AZA and 3-tigloyl-azadirachtol and the effects on western flower thrips, Frankliniella occidentalis (Pergande), were studied. Residues of AZA and 3-tigloyl-azadirachtol from substrates with different contents of organic matter [pure culture substrate (CS), CS-sand mixture] and from various plant parts were quantified by high-performance liquid chromatography-mass spectrometry (HPLC-MS). The dissipation trends of AZA and 3-tigloyl-azadirachtol were similar within the same substrates. A slower decline of both active ingredients was measured with CS than with CS-sand mixture. Residue analysis of the bean plants showed that only small proportions of the initial amounts of AZA and 3-tigloyl-azadirachtol applied to the substrate were present in the plant (0.3-8.1%). Variable amounts of residues of the active components in relation to plant parts and time of analysis indicated a different translocation pattern for the two active ingredients. Higher residues of the active ingredients were found in roots and stems after neem application using CS, whereas higher residues were found in leaves after CS-sand mixture treatments. Mortality of F. occidentalis after NeemAzal-U soil applications reached up to 95% on CS-sand mixture, compared with 86% in CS.

KW - Frankliniella occidentalis

KW - Neem

KW - Phaseolus vulgaris

KW - Systemic effects

UR - http://www.scopus.com/inward/record.url?scp=33746457341&partnerID=8YFLogxK

U2 - 10.1002/ps.1239

DO - 10.1002/ps.1239

M3 - Article

C2 - 16752388

AN - SCOPUS:33746457341

VL - 62

SP - 759

EP - 767

JO - Pest management science

JF - Pest management science

SN - 1526-498X

IS - 8

ER -