Correlation and Path Analysis Between Node Snap Strength (NSS) and Stalk Microstructure of Maize Inbred Line

To identify the relation between node snap strength(NSS) and stalk microstructure,NSS of 22 maize inbred lines was measured and microstructure of vascular was observed through optical microscope.Based on the data,the correlation and path analysis between NSS and stalk microstructure was studied.The results showed that the NSS difference of inbred lines reached significant or extremely significant level.The variation coefficient of single vascular area,25.06%,was maximal;which was followed by variation coefficient of vascular number,19.97%.The increase of vascular number went against the enhancement of NSS(r=-0.54**,r=-0.55**),but the increase of vascular area contributed to the enhancement of NSS(r=0.48*,r=0.43*).Path analysis indicated the direct effect of vascular number to NSS was maximal followed by the muscular area at 6 days and 15 days after pollination.At 6 days after pollination,contributions of minimal diameter and average diameter of vascular affected NSS through the indirect affection of vascular number.