Shashi Meena, Neetu Kachhwaha and Geeta Meena
Present study was carried out to investigate the toxic effect of plant extracts of Annona squamosa, Ailanthus altissima, Calotropis procera, Syzygium aromaticum and Azadirachta indica on pest grasshopper, Chrotogonus trachypterus Blanchard. This is a widely distributed polyphagous insect pest causing severe damage to a wide variety of plants and crops in seedlings stage. Percent mortality was recorded for newly hatched nymphs (0-2 day old) when treated residually whereas adult grasshoppers were treated with topical application method. LC50 and LC90 value of A. indica possessed the highest toxic activity against newly hatched nymphs with 1.998 and 9.238 percent. Similarly, maximum toxic activity with LC50 and LC90 value (11.487 and 14.982 percent) recorded for adult males and females, respectively on the same. Amongst five plant extracts, A. indica was proved more toxic than all other plant extracts while, females required higher concentration of extract than males. Decreasing order of toxicity was recorded to be Azadirachta indica > Annona squamosa > Ailanthus altissima > Syzygium aromaticum > Calotropis procera. Using plant products could be considered as possible means in integrated pest management (IPM) programs for C. trachypterus grasshopper
