Management of Maize Stem Borer Using Sowing Date at Arsi-Negele

Abstract

In Ethiopia maize yield ranges from 2000-kg ha'1 tolO, 000-kg ha'1. The variation isattributed to many factors among which lepidopterous stem borers are the most important. As part of integrated management of stem borers, sowing date trials were
conducted at Arsi-Negele. Ten sowing dates starting from March 20 at 10 days interval were tested. The trials were laid out in two sets: with and without cypermethrin treatment. The result obtained indicates that early sowing with cypermethrin treatment
doubled the yield of maize grain. If maize has to be grown without cypermethrin treatment, it should be sown between 20 April and 10 May. The highest economic return with cypermethrin treatment at the rate of 0.30 kg a.i ha'1 applied at 4 and 6 weeks after crop emergence was obtained with early sowing indicating that early infestation o f stem borer is very detrimental for maize production at Arsi Neg le .