Evaluating the Impact of Border Crops on Aphid (Hemiptera: Aphididae) Infestation and Damage in Butternut Squash ( Cucurbita moschata )

Abstract

Aphids cause loss of quality and value in butternut crops due to pest injury and the transmission of viruses in a non-persistent manner. A field experiment was conducted in Daylesford, Gweru in August 2012/2013 planting season to evaluate border cropping practice as a management strategy for aphid infestation and damage in butternut squash (Cucurbita moschata). The experiment was arranged as a 2 x 2 + 1 factorial in a randomised complete block design (RCBD) replicated 4 times. Treatments were Maize (Zea mays) border planted at 25 000 and 45 000 plants/ha and sorghum (Sorghum bicolor) border planted at 200 000 and 260 000 plants/ha plus a butternut crop with no border (control). All borders were planted 0.5 m from the butternut crop. Data on aphid counts on borders and on butternuts, disease incidence, yield and land equivalent ratio for the intercrops was recorded. Results showed that, border crops and border density interacted significantly (p < 0.05) to to reduce aphid population, disease incidence and yield of butternuts. From the results, butternut plots bordered by maize at 45 000 plants/ha recorded the highest butternut yield (16t/ha), least aphid population and least viral disease incidence during the 7th week after planting when compared to control. Based on these findings it can be concluded that the use of maize border cropping at 45 000 plants/ha can be effective in controlling aphids in butternuts.