Toxicity screening of various plant extracts against nematodes Meloidogyne incognita Chitwood and Radopholus similis Cobb and characterization of their nematicidal components /
Guzman, Ruth Sarra
Toxicity screening of various plant extracts against nematodes Meloidogyne incognita Chitwood and Radopholus similis Cobb and characterization of their nematicidal components / Ruth Sarra-Guzman - Los Ba�os, Laguna, Cavite State University- Main Campus, 1984. - 197 pages : illustrations ; 28 cm.
Thesis (Ph.D. - - Plant Pathology) University of the Philippines, College, Laguna.
Includes bibliographical references.
GUZMAN, RUTH SARRA. University of the Philippines at Los Banos, July 1984. Toxicity Screening of Various Plant Extracts Against Meloidogyne incognita Chitwood And Radopholus similis Cobb and Characterization of their Nematicidal Components. Major Professor: Dr. Romulo G. Davide
Solvent extracts of eight plant species were screened for toxicity against two economically important nematode genera, namely: Meloidogyne incognita Chitwood and Radopholus similis Cobb. The plant species were: Anthocephalus chinensis (Lamb.) Rich ex Walp, Desmodium gangeticum (Linn.) DC, Artemisia vulgaris Linn., Eichornia crassipes (Mart.) Solms, Leucaena leucocephala (Lam.) de Wit, Allium cepa Linn., Allium sativum Linn. and Moringa oleifera Lam. The extracts showed definite indications of toxicity in immersion bioassay and pathogenicity tests. However, degrees of toxicity varied among the different species although results could favorably compare with toxicity values obtained with the standard pesticides used namely, Nemacur 10 G (fenamiphos), Temik 10 G (aldicarb) and Rotenone, a pesticidal compound taken from Derris elliptica. Mortality data after 48 hours and percent reduction in hatchability and infection parameters were the bases for comparison, i.e., number of egg mass, nematode population in root and number of galls for M. incognita; lesion number and nematode population in root and soil for R. similis.
The crude extracts of A. chinensis, E. crassipes and As cepa showed outstanding results in the toxicity tests. Subsequently, these extracts were fractionated by preparative thin-layer chromatography and purified in order to isolate the active principle. Separated fractions were again bioassays on the test organisms to test their nematicidal activity in this purified state. The Ae cepa crystals, Fraction 2 of A. chinensis and Fraction 1 of E. crassipes showed high toxicity.
Characterization of the active components by ultraviolet and infrared spectrophotometry suggested the presence of a ketone in the A. cepa crystal, a phenolic aldehyde in A. chinensis Fraction 2 and a carboxylic acid in E. crassipes
Fraction 1 as responsible for nematicidal activity.
Plants--Diseases
581.2 / G99 1984
Toxicity screening of various plant extracts against nematodes Meloidogyne incognita Chitwood and Radopholus similis Cobb and characterization of their nematicidal components / Ruth Sarra-Guzman - Los Ba�os, Laguna, Cavite State University- Main Campus, 1984. - 197 pages : illustrations ; 28 cm.
Thesis (Ph.D. - - Plant Pathology) University of the Philippines, College, Laguna.
Includes bibliographical references.
GUZMAN, RUTH SARRA. University of the Philippines at Los Banos, July 1984. Toxicity Screening of Various Plant Extracts Against Meloidogyne incognita Chitwood And Radopholus similis Cobb and Characterization of their Nematicidal Components. Major Professor: Dr. Romulo G. Davide
Solvent extracts of eight plant species were screened for toxicity against two economically important nematode genera, namely: Meloidogyne incognita Chitwood and Radopholus similis Cobb. The plant species were: Anthocephalus chinensis (Lamb.) Rich ex Walp, Desmodium gangeticum (Linn.) DC, Artemisia vulgaris Linn., Eichornia crassipes (Mart.) Solms, Leucaena leucocephala (Lam.) de Wit, Allium cepa Linn., Allium sativum Linn. and Moringa oleifera Lam. The extracts showed definite indications of toxicity in immersion bioassay and pathogenicity tests. However, degrees of toxicity varied among the different species although results could favorably compare with toxicity values obtained with the standard pesticides used namely, Nemacur 10 G (fenamiphos), Temik 10 G (aldicarb) and Rotenone, a pesticidal compound taken from Derris elliptica. Mortality data after 48 hours and percent reduction in hatchability and infection parameters were the bases for comparison, i.e., number of egg mass, nematode population in root and number of galls for M. incognita; lesion number and nematode population in root and soil for R. similis.
The crude extracts of A. chinensis, E. crassipes and As cepa showed outstanding results in the toxicity tests. Subsequently, these extracts were fractionated by preparative thin-layer chromatography and purified in order to isolate the active principle. Separated fractions were again bioassays on the test organisms to test their nematicidal activity in this purified state. The Ae cepa crystals, Fraction 2 of A. chinensis and Fraction 1 of E. crassipes showed high toxicity.
Characterization of the active components by ultraviolet and infrared spectrophotometry suggested the presence of a ketone in the A. cepa crystal, a phenolic aldehyde in A. chinensis Fraction 2 and a carboxylic acid in E. crassipes
Fraction 1 as responsible for nematicidal activity.
Plants--Diseases
581.2 / G99 1984