effect of ethanolic plant extracts along with releasing eggs of orius horvathi (heteroptera: anthocoridae) against the western flower thrips frankliniella occidentalis (thysanoptera: thripidae)

The present research aimed to study the insecticidal activity of four ethanolic extracts of cercis siliquastrum l., calendula officinalis l., peganum harmala l., melia azedarach l. against frankliniella occidentalis (pergande) as well as hatching time and hatching rate of orius horvathi (reuter). the results revealed that the extracts had no significant effect on the hatching time of the predatory bug. the result showed concomitant use of the extracts with releasing eggs of the o. horvathi could control thrips effectively. the lowest (73.66 ± 7.01%) hatching rate belonged to p. harmala, indicating concomitant use of p. harmala extract with releasing eggs of o. horvathi can cause effective control of adult thrips. moreover, concomitant use of c. siliquastrum, c. officinalis extracts with releasing eggs of o. horvathi can control immature thrips effectively.