Pepper-Garlic Intercropping System Improves Soil Biology and Nutrient Status in Plastic Tunnel
A two year (2009-2011) experiment was conducted to investigate effect of pepper-garlic intercropping system on soil biology and nutrient profile in plastic tunnel to overcome continuous monocropping obstacles. During first year’s trial, garlic cloves of four cultivars (G026, G025, and G087 for the harvest of bulbs) were intercropped between two rows of pepper seedlings (cv. Golden Pepper) on each bed. Similarly, garlic bulb (cv G064 for the harvest of green seedlings) was sandwiched between two rows of pepper seedlings. During 2nd year, the pepper crop was transplanted on the same beds already having garlic in the field of previous crop, following the same geometry. Sole pepper was grown as control. Both crops received uniform fertilization and irrigation as per requirements of pepper. Results revealed that concentration of soil bacteria and actinomycetes was higher respectively after one month of garlic intercropping during both the years of study as compared to the sole pepper; however, fungal population exhibited a diminishing trend. Soil protective enzyme activity (invertase, urease, and alkaline phosphatase) also showed dynamic changes after the intercropping of garlic. The principal soil nutrients (NPK) attained higher levels in pepper-garlic co-growth treatments as compared to the sole pepper The intercropping with green garlic (cv. G064) resulted highest nutrient levels suggesting that the effect might be cultivar specific. It was concluded that the intercropping of pepper with garlic enhances the soil fertility by changing nutrient levels, enzymatic activity and the soil microbial population. Overall, the pepper-garlic intercropping model provides a cost effective and eco-friendly organic farming system for vegetable growers.