Role of refugia graminae in push - pull management of stem borer species of Zea Mays L. and Sorghum bicolor L.

Abstract

This study aimed at determining the role of graminae refugia in push – pull management of stem borer species of Zea mays L. and Sorghum bicolor L. and refugia graminae. It involved two growing gramineous crops: maize Zea mays L. and Sorghum bicolor L. and three gramineous forages: Napier grass Pennisetum purpureum Schumach, Sudan grass and giant Setaria grass. These were planted both in pure and mixed stands and sampling for the borer infestation done throughout the phenology of crops .Field and laboratory bioassays were conducted to determine biophysical efficacies of the control strategy from stem borer fecundities. P.purpruem was the most effective gramineous forage refugia with the potency of being utilized in the push – pull management strategy of the stem borers. It reduced damage caused by stem borers to 2.02% and 5.77% in maize and sorghum respectively. This implies that it has desirable traits attractive to the stem borers especially the great devastating B. fusca as chemical and biophysical morphology and stem diameter The gramineous biocontrol agent had a significant (F = 46.29*; p < 0.05) effect on the damage caused by stem borers to maize and sorghum. The Napier grass was the most preferred forage refugia. However, more research should be conducted to determine the augmention of Napier grass as the appropriate “push crop “when utilized in a push – pull management strategy.