Effects of pepper species (Capsicum sp. L.) and row arrangement with ‘egusi’ melon (Citrullus colocynthis (L.) Schrader) on crop growth and yields

The rate of exposure to competition for growth resources in an intercrop is a determinant of crop performance. Field experiments were conducted in 2018 and 2019 at the Federal University of Agriculture, Abeokuta, Nigeria to determine the effects of row arrangement of two pepper species (Capsicum chinense (L.) and Capsicum frutescens (L.) with “Egusi” melon (Citrullus colocynthis (L.) on growth and fruit yield of component crops. Pepper species were arranged at 1:1, 2:1 and 3:1 rows with Egusi melon, with mono-cropped pepper species and Egusi melon as checks. Interaction of row arrangement and pepper species affected pepper plant height while interaction of row arrangement with pepper species and year of cultivation affected pepper yield and yield attributes. Plants were taller with C. frutescens (80 cm) with 3:1 row arrangement but with 2:1 arrangement with C. chinense (51 cm). Plants were taller with C. frutescens in 2019 (93 cm) than in 2018 (61 cm) but were similar with C. chinense, in both years. With C. frutescens, number of fruits and fruit yield in both years (4.03-4.17 t ha-1) were greater with 3:1 row arrangement. With C. chinense, number of fruits and fruit yield (2.40 t ha-1) were greater with 2:1 row arrangement only in 2019. Melon seed yield was 40% higher in 2019 relative to 2018. Both pepper species at 2:1 row arrangement showed slight symptoms of anthracnose severity but no symptoms at 3:1 row arrangement. The 3:1 row arrangement of pepper can improve the yield of pepper species with Egusi melon. The 3:1 row arrangement of intercropping pepper with egusi melon is recommended as it gives relatively higher yields of pepper with relatively low anthracnose disease occurrence and severity. This gives a higher farm return with lower risk of diseases.