Intercropping Sunflower with Soyabeans Enhances Total Crop Productivity

Summary

There is a need to develop sustainable and productive cropping systems for edible vegetable oilseeds in tropical Africa. Field trials were conducted during the late cropping season (July–Nov.) of 2001 and 2002 to determine the grain yields, and other yield attributes of sunflower and soyabeans and their productivity under monocropping and intercropping. Three sunflower (Helianthus annuus L.) varieties (a local adapted var. Funtua and two exotic varieties Isaanka and Record from Argentina) and five improved, high yielding soyabean (Glycine max (L.) Merrill) varieties: TGx 1448-2E (late), TGx 1440-1E (late), TGx 1019-2EB (medium), TGx 1740-2F (early) and TGx 1485-1D (early maturing) were used. Funtua had significantly greater head weight and diameter, achene number and weight per head than Isaanka and Record during the dry and relatively hot cropping season of 2001. Cropping system significantly reduced soyabean grain yield in intercropping, relative to monocropping, except when soyabean was intercropped with Isaanka in 2001 and Record in 2002. All yield attributes of both crops exhibited significant positive relationship with grain yields, except height to the lowest pod of soyabean. TGx 1448-2E and TGx 1440-1E intercropped with Isaanka and Record had average grain yield of 1043 and 1081 kg ha–1 and land equivalent ratios (LER) of 1.47 and 1.58, respectively. It is recommended that intercropped combination of TGx 1448-2E/Isaanka and TGx 1440-1E/Record be used to improve yields of vegetable oilseeds.