Seed priming effects of Yuhuangjin on spring maize.

The chemical regulation of crops is becoming a leading agro -technical measure for combating corn lodging. Yuhuangjin (YHJ) is a plant growth regulator which mainly affects on stem lodging. This study was aimed to provide a theoretical reference for control and prevention technologies for the cultivation of high -density maize. A split pot experiment design was conducted in 2012 for the field condition whereas four YHJ treatment concentrations (0ml, 4ml, 8ml and 16ml) were conducted in Jilin province during 2011 under greenhouse conditions. Optimum application of YHJ (4mL/Kg) on maize seed effectively influenced stalk-lodging resistance, bending strength, ear height and yield. When the concentration was ≥8mL/kg, the chemical regulation-mediated inhibition of the underground portion of the plant was greater than its aboveground counterpart. Moreover, dramatic reduction was also observed in height of the treated plants (31.99% for 8mL/kg and 39.91% for 16mL/kg). In the field, YHJ treatment reduced the internode length between internodes I -III and increased the length between internodes IV-VII. These differences in the length between internodes I -III and internodes IV-VII were accompanied by a slight increase in ear height. Under high-density conditions, the seed dressing effect on lodging resistance was pronounced but lodging rate decreased by 10.41%.