Effects of Zinc,Iron,and Molybdenum Combined Application on the Yield and Quality of Alfalfa

The effects of combined application of Zinc (Zn),Iron(Fe),and Molybdenum(Mo) fertilizers on the forage yield and quality of alfalfa were studied by the field experiment.The results indicate that microelement fertilizers could remarkably increased the 1st cut forage yield of alfalfa by 18.1% when the application amounts were Zn 5 kg· hm-2,Fe 7.5 kg· hm-2,and Mo 0.45 kg· hm-2.But there were no significant effect on the yields of 2nd,3rd,and 4th cut.Among the three microelements,Zn fertilizer had significant effect to increase forage yield,but Fe and Mo fertilizer not.Reasonable combined application of microelement fertilizers significantly increased the feeding value of alfalfa,i.e.higher contents of crude protein(CP),crude fat(EE) and Ca,and lower content of crude fiber(CF),when the applied amounts were Zn 10 kg· hm-2,Fe 15 kg· hm-2,and Mo 0.225 kg· hm-2.All of the three microelement fertilizers could increase the quality of alfalfa;the effect of Zn fertilizer was considerable,but those of Fe and Mo fertilizer insignificant.