Comparison and Characterization of Garlic (Allium sativum L.) Bulbs Extracts and Their Effect on Mortality and Repellency of Tetranychus urticae Koch (Acari: Tetranychidae)
Autor: | Ricardo Torres Ch, Gloria Eugenia López P, Carlos Augusto Hincapié Ll. |
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Rok vydání: | 2008 |
Předmět: |
plant extracts
biology Diallyl disulfide Acaricide Extraction (chemistry) Supercritical fluid extraction biology.organism_classification Allium sativum chemistry.chemical_compound Horticulture Diallyl trisulfide chemistry Botany Liliaceae Animal Science and Zoology Petroleum ether miticidal effect Tetranychus urticae two-spotted spider mite Agronomy and Crop Science |
Zdroj: | Chilean journal of agricultural research v.68 n.4 2008 SciELO Chile CONICYT Chile instacron:CONICYT |
ISSN: | 0718-5839 |
DOI: | 10.4067/s0718-58392008000400001 |
Popis: | Tetranychus urticae Koch is a pest that causes great economic losses because it attacks a wide range of host plants. Also, some populations have developed resistance against commercial acaricides. This work compares different extracts from garlic (Allium sativum L.) bulbs measuring their toxicity and repellency effects on T. urticae. Extracts were obtained using as solvents CO2 in supercritical conditions (CSC), ethanol and petroleum ether using Soxhlet and soaking methods and soaking in water. The supercritical fluid extraction technique allows for obtaining extracts at low temperature using high pressures, avoiding compound degradation and making possible solvent separation by exposing the extract at room temperature. Mites were bred on bean plants (Phaseolus vulgaris L.) in a laboratory environment in Laureles Campus, Universidad Pontificia Bolivariana, Medellin, Colombia. Mortality was evaluated putting 10 mites in P. vulgaris 3 cm diameter leaf discs previously submersed in the extract. The lowest mean lethal concentrations (LC50) were obtained with the CSC method (8118.8, 5410.5, 2820.6 mg kg-1 at 24, 48 and 72 h, respectively). Extracts were characterized using gas chromatography/mass spectrometry (GC/MS), finding vinyl dithiins (63.11%), diallyl disulfide (10.88%) and diallyl trisulfide (10.4%) as the main compounds in the CSC extract. The main conclusion is that, in comparison with other techniques of extraction from garlic bulbs used in this study, supercritical fluids allow for obtaining extracts with a higher concentration of biologically active compounds against T. urticae. |
Databáze: | OpenAIRE |
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