Effects Of Sowing Date And Variety On Spring Maize Lodging And Yield In Eastern Hebei Province

In this study,the anti-lodging varieties(DK 516,JNK 728)and lodging varieties(Z 1453 and GD 5)were used for the sowing date test.The decrease in spring maize yield after lodging was not conducive to the increase in production and efficiency of spring maize.The lodging characteristics and yield of maize under different sowing dates in eastern Hebei province were studied.The research results were as follows:1.The sowing date had different effects on the lodging rate,the type of lodging and the level of lodging of spring maize.With the delay of the sowing date,the lodging rate and lodging level of each variety showed an increase trend.Comparing the lodging rate and lodging level between varieties were expressed as GD 5 > Z 1453 > JNK 728 > DK 516.The type of lodging was mainly root lodging.2.With the delay of the sowing date,the natural plant height,plant height,dry matter weight,stem diameter and leaf orientation showed a reduce trend.The plant height,natural plant height and stem diameter of GD 5 were the largest,and the stem of JNK 728 was the second,and the stem and plant height of DK 516 were the lowest.3.With the delay of the sowing date,the root dry matter weight,the average diameter of root,the surface area of root,the volume of root were decreased.The root dry matter weight,the average diameter of root,the surface area of root,the volume of root DK 516 were the biggist.The dry matter weight,the root dry matter weight,the average diameter of root,root number the surface area of root,the volume of root of JNK 728 were larger.The average dameter of root,the surface area of root,the volume of root GD 5 were the smallest.4.Correlation analysis showed that the lodging rate of spring maize was positively correlated with plant height,and negatively correlated with root dry weight,root width at 10 cm,average root diameter,root surface area and root volume.5.With the delay of the sowing date,the yield of spring maize was declined.The yield difference between different varieties was not significant,and the yield of each variety reached the maximum on the S1 sowing period.As the sowing date was delayed,the length of the ear,the diameter of ear and the grain per spike decreasd,and the bald ear length rised.The difference in yield components during the sowing date reached a significant level.DK 516 had the earliest diameter of ear and the bald ear length was the shortest;JNK 728 had the thickest diameter of ear,had the maximum the grain per spike and 1000-grain weight.The grain per spike and 1000-grain weight in GD 5 were the lowest;the bald ear length was the longest.