Meat bone meal as fertilizer for oat

Meat bone meal contains considerable amount of nutrients (on average 8% N, 5% P, 1% K and 10 % Ca). Therefore, it can be used as fertilizer for different crops. Whether meat bone meal (LL) can achieve similar effect in increasing the grain yield and grain quality of oat as meat bone meal mixed with biotite (LB), meat bone meal mixed with blast furnace slag (LB) and meat bone meal mixed with lime (LK) or not were analyzed in this study. Two field experiments: one in Viikki experimental farm, and other in suitia experimental farm of the University of Helsinki were carried out in the summer of 2005. LL, LB, LM, and LK were applied in three N levels: 60, 90 and 120 kg N ha-1 in Viikki and Suitia experimental farms. In both experimental farm, oat grain yield, oat grain test weight, and oat 1000-grain weight did not differ between the fertilizer types. In Suitia experimental farm, oat grain yield and 1000-grain weight increased with increasing the N-levels but not oat test weight whereas in Vikki experimental farm, oat grain yield, oat test weight, and oat 1000-grain weight did not increase with increasing the N levels. Since the N/P ratio of meat bone meal is considerably narrower than the normal nutrient uptake ratio of cereals, hence, if it is applied to meet the N demand of crops then P in soil would be surplus. Therefore, due to the P residual effect, it is recommended not to use meat bone meal in the following year or even for the whole crop rotation but recommended to grow green manure crops as for nitrogen resources to organic farms after using meat bone meal. Since K content of meat bone meal is rather low therefore, to balance the nutrient contents in meat bone meal, some of the most viable alternatives for additional K such as biotite, vinasse, potassium sulphate could be added to meat bone meal to achieve meat bone meal-NPK contents more optimal for crops