Grain Yield and Nutrient Balance

Studies have shown that soil fertility declines after cropping and this becomes greater with each successive cropping. The situation is likely to be more serious under mixture since mixtures take up more nutrient than sole crops. Thus, declined in soil fertility result in decline in production in the tropics. This may be due to the nature of the tropical soil and the mining of the soil by the crops. This gives a negative balance of most of the essential nutrients at the end of each season. The decline of these essential nutrients will therefore lead to lower yield of these crops. Results from the experiment shown that there was yield reduction of the component crops in the intercropping system by 38% for soybean and 28% for maize. However, Land Equivalent Ratio value was 1.34. Similarly, Crop Compensation Ratio was 2.2 and the Total Crop Performance Ratio was 2.67. These show that intercropping makes use of land more efficiently such that more land would be needed under sole cropping to obtain the yields in the intercropping. Also, intercropping maize and soybean reduce the soil depletion of nitrogen by both sole maize and soybean and ensures the sustainability of the system better