Introduction experiment of silage maize in Zhengzhou

Ten single cross hybrids of maize were introduced, and their proper harvesting stage and the correlation among agronomical traits were studied for selecting the varieties adapted to Zhengzhou. The results indicated that the proper harvesting date for silage making was in the stage of wax ripeness in terns of yield, agronomical traits and nutrient contents. The plant height, stem diameter, ear length and ear diameter showed the positive correlation with yield. The CP content was positively correlated with leaf proportion. CF content negatively correlated with CP content. Out of 10 varieties, Ludan 981, Zhengdan 968 and Jundan 18 were better and could be extended in Zhengzhou.