학술논문
Insecticidal Activity of Jatropha Extracts Against the Azalea Lace Bug, Stephanitis pyrioides (Hemiptera: Tingidae)
Horticultural Entomology
Horticultural Entomology
Document Type
Survey
Source
Journal of Economic Entomology. February 2023, Vol. 116 Issue 1, p192, 10 p.
Subject
Language
English
ISSN
0022-0493
Abstract
Resistance to pesticides and residual toxicity of active ingredients or breakdown products in soil, water, and nontarget organisms have spurred a search for more selective pesticidal compounds. For centuries, extracts [...]
We assessed bioactivity of ethanolic extracts from 35 species of Jatropha L. against an ornamental plant pest, the azalea lace bug, Stephanitis pyrioides (Scott). Jatropha extracts were prepared by air-drying stem, root, or whole plant material, grinding the tissue into a fine powder, adding 70% ethanol, and then vacuum filtering the contents. Emulsions included the extract diluted to the desired concentration in de-ionized water and 10% dimethyl sulfoxide (DMSO). Treatments involved pipetting 20 [micro]l of emulsion onto three adult lace bugs in each well of a 96-well microtiter plate. Treated wells served as replicates for each of six extract concentrations and were arranged according to a RCBD. Extracts of Jatropha clavuligera Mull. Arg. and J. ribifolia (Pohl) Ballion from 0.06 to 0.50% were the most acutely bioactive with bug mortality exceeding that of the positive control -azadirachtin, a terpenoid and chief active ingredient in neem oil. At 1.00%, extracts of J. clavuligera, J. ribifolia and azadirachtin killed 100% of bugs within 3 hr. Jatropha clavuligera induced the lowest LC50 and ranked first in insecticidal potency based on [greater than or equal to]98% of bugs dying within 3 hr. Extracts of J. curcas L., J. gossypiifolia L., J. excisa Griseb, and azadirachtin were equally bioactive; although after 3 hr, the three Jatropha species killed bugs faster. When compared with DMSO, all extract emulsions were bioactive against adult bugs. Thus, active ingredients in a new biopesticide could be sourced from the stem, root, or whole plant extracts of at least five Jatropha species. Key words: ornamental pest, biological pesticide, natural product, insect bioassay, tropical plant
We assessed bioactivity of ethanolic extracts from 35 species of Jatropha L. against an ornamental plant pest, the azalea lace bug, Stephanitis pyrioides (Scott). Jatropha extracts were prepared by air-drying stem, root, or whole plant material, grinding the tissue into a fine powder, adding 70% ethanol, and then vacuum filtering the contents. Emulsions included the extract diluted to the desired concentration in de-ionized water and 10% dimethyl sulfoxide (DMSO). Treatments involved pipetting 20 [micro]l of emulsion onto three adult lace bugs in each well of a 96-well microtiter plate. Treated wells served as replicates for each of six extract concentrations and were arranged according to a RCBD. Extracts of Jatropha clavuligera Mull. Arg. and J. ribifolia (Pohl) Ballion from 0.06 to 0.50% were the most acutely bioactive with bug mortality exceeding that of the positive control -azadirachtin, a terpenoid and chief active ingredient in neem oil. At 1.00%, extracts of J. clavuligera, J. ribifolia and azadirachtin killed 100% of bugs within 3 hr. Jatropha clavuligera induced the lowest LC50 and ranked first in insecticidal potency based on [greater than or equal to]98% of bugs dying within 3 hr. Extracts of J. curcas L., J. gossypiifolia L., J. excisa Griseb, and azadirachtin were equally bioactive; although after 3 hr, the three Jatropha species killed bugs faster. When compared with DMSO, all extract emulsions were bioactive against adult bugs. Thus, active ingredients in a new biopesticide could be sourced from the stem, root, or whole plant extracts of at least five Jatropha species. Key words: ornamental pest, biological pesticide, natural product, insect bioassay, tropical plant