Use of low cost pest exclusion nets can boost cabbage yield

In this study, low-cost pest exclusion nets (lcPENs) were evaluated to determine their ef fi cacy in reducing pest infestation and enhancing yields of cabbage at KALRO Kabete and PTC (Practical Training Centre) Thika, Kenya, from March to September 2011 both at nursery and fi eld production levels. Nets of two-mesh sizes (0.9 mm and 0.4 mm) were used whereby the 0.9 mm net was either impregnated or not impregnated with alpha cypermethrin to enhance ef fi cacy through repellency effects of the pesticides. The lcPENs ef fi ciency was compared with no-net use and grass shading (farmer practice) in a completely randomized block design with fi ve replications. Results showed that diamondback moth ( Plutellaxylostella ) larval infestation was lower ( P <0.05) on cabbages covered with lcPENs both at nursery and fi eld level. At nursery, aphids were lower ( P <0.05) on seedlings covered with insecticide-impregnated lcPEN but in fi eld conditions, there was no difference among the lcPENs. Cabbage yield was higher ( P