Evaluation of Effective Dose of Monocrotophos for the Contro] of Mango Hopper Amritodus atkinsoni Lethierry (Cicadellidae : Homo-piera) by Injection Method and Its Comparison with Foliar Application 

Abstract

Three doses viz., 0.15, 0.25-and 0.30 ml aii. ‘of monocrotophos (Nuvacron 40 EC)/ ‘cm girth as stem. injection and recommended dose viz., 0.04% monocrotophos by foliar application were applied after flowering on alfanso variety of mango tree and their effectiveness were compared, Monocrotophos 0,25 and 0,30 ml a.i./cm girth as stem injection and monocrotophos 0,04% as foliar application decreased the population of mango hopper significantly after one week of treatment and were also remained effective upto one month. One month after application, the effectiveness of monocrotophos 0.04% by foliar application was reduced. The lower dose (0.15 ml a.i./em girth) of Monocrotophos was effective only after third week of injection. Monocrotophos 0.25 ml a.i/cm girth was the most effective lowest dose which had controlled the hopper population for more than five weeks.