Residual Effects of Organic Manure on Onion Varieties‘ Mineral Content

This study was conducted to determine the residual effects of chicken manure applications on nutrients in leaves and bulbs of second crop onion that grown after lettuce in greenhouse conditions. In the study, residual effects of chicken manure in 4 different doses (control, 20 t ha-1, 40 t ha-1, 60 t ha-1) and chemical fertilizers applied in the recommended amounts are investigated. Three onion varieties, called Burgaz, Snow white, Champion, were used. In the study, the lowest nutrient uptake was observed in control. However, the highest mineral content in leaves and bulbs were determined in the plots, that on average 40 t ha-1 chicken manure was applied to. In terms of leaf nutrient content, when the varieties were compared to each other, Ca, Mg, and Cu contents were found to be the highest in the Burgaz variety. Phosphorus, Zn, Mn contents were analyzed to be the highest in Snow white while N values determined maximum in Champion. The Champion variety contained higher nutrient values in bulbs.