Effect Of Yuhuangjin Treatment On Spring Maize Seed Growth And Development

The application of chemical regulation of crops is becoming a leadingagro-technical measure to solve the corn lodging problem. By tests and research ofdifferent concentrations of chemical regulation on seed dressing in spot field trials, westudy the mechanism of chemical regulation (YuHuangJin) of Spring Corn seed’sgrowth and development in central region of Jilin Province in the aim to provide atheoretical reference for control and prevention technologies of cultivatinghigh-density maize. So far, we have made the following conclusions:1. Different concentrations of YuHuangJin dressing influence greatly seedgermination rate.8d after planting seeds germination rate dropped about16.7%and21.3%at the concentrations of8ml/kg and16ml/kg respectively compare to thecontrol group, whereas at4ml/kg there were no noticeable difference.2. After YuHuangJin dressing treatment, the2nd leaf length and the2nd and3rdleaves width of the trefoil stage were significantly inhibited, leading to leaf area’sreduction.3. YuHuangJin dressing can inhibit the growth and development of the seedling,root length and radicle growth.With the increase of YuHuangJin dressing concentration, the seedling shoot drymatter accumulation above ground and root dry weight tend to reduce gradually, butthe seedling root ratio trend’s increased first then decrease later on. When theconcentration is≥8ml/kg, the chemical regulation inhibition of the underground partis greater than its above counterpart. Therefore the optimal YuHuangJin dressingconcentration is4ml/kg. 4. On the field, chemical regulation seed dressing treatment induces reduction ininternode’s length between I-III internodes, increase in length between IV-VIIinternodes. This difference of length between internodes I-III and internodes IV-VIImakes slight increase in the ear height,that is “rebound effect”.5. Under high concentration chemical regulation treatment, stalk lodging resistanceand stretch bending strength were significantly enhanced with90,000/hm2plantingdensity. Treated seed’s second to fourth internode stem bending strength increased byan average of7.14%compared with the control group, with25.4%increase in stretchbending strength and lodging resistance rate reduces by10.41%. Seed dressing effecton lodging resistance under high density planting is very great.At low density(70,000/h m2),harvesting shows no difference between the dressingand undressing seed; whereas at high density, the dressing corn yield increases by6.91%compare to the control group. Under high density planting (90,000/h m2), theyield increase is mainly due to the effective increase of productive ears per unit area.