Application Of Plant Growth Regulator In Delaying Grain Senescence

In order to filter out plant growth regulators and corresponding concentrations for preventing premature aging of 'Nongda 8' and 'Nongda 10',five plant growth regulators and three concentrations and a control group of water were selected and took a randomized block design in the treatment.After the determination of effects of chemical treatment on plant height,leaf area,chlorophyll content,photosynthetic characteristics,stress enzyme activities and yield of millet.The result is as follows:1.Effects of different chemical treatments on agronomic traits of millet:When the gibberellic acid concentration was 30 mg/L,the increase in the plant height of 'Nongda 8' was the highest,while for'Nongda 10',the gibberellin concentration was 30 mg/L.The best treatment effect.Paclobutrazol can shorten millet plants,and 'Nongda 8' and 'Nongda 10' plant heights will decrease with increasing paclobutrazol concentration.When the concentration of 6-BA was 10 mg/L,the leaf area of 'Nongda 8'was significantly larger than that of the non-plant growth agent.The best treatment effect of 'Nongda 10'was also 6-BA.2.Effects of different chemical treatments on chlorophyll content of millet:Different plant growth agents with different concentrations have different degrees of influence on chlorophyll a and chlorophyll b of 'Nongda 8' and 'Nongda 10'.When foliar spraying of 6-BA,the effects of chlorophyll a and b on the two millet varieties were the most obvious.3.Effects of different chemical treatments on photosynthetic characteristics of millet:The effect of spraying growth agent on 'Nongda 10' was better than that of 'Nongda 8' and could effectively reduce the decline of photosynthetic performance of 'Nongda 10' at the grain-filling stage and delay the growth of millet leaves.senescence.6-BA,paclobutrazol,gibberellin,and KT could all effectively increase the Pn value of the two millet varieties,but 6-BA had the best spraying effect.The best spraying concentration was 10 mg/L,followed by paclobutrazol.4.Effects of different chemical treatments on POD and SOD of millet:For the enzyme activity of the leaves,the spraying agent had a better effect on 'Nongda 8' than 'Nongda 10'.and spraying paclobutrazol could improve POD and SOD activity of 'Nongda 8,and 'Nongda 10',and delayed the aging of millet.The optimum concentration of paclobutrazol in both varieties was 300 mg/L.5.Effects of different chemical treatments on grain yield and yield components:Spraying different concentrations of gibberellin,paclobutrazol,2,4-D,KT,and 6-BA could increase the yield of 'Nongda 8'and 'Nongda 10',and it all had certain effects on their yield components including ear length,ear diameter,ear weight,ear weight,and 1000-grain weight.When the paclobutrazol concentration was 300 mg/L,the yield of 'Nongda 8' was the highest,and when the paclobutrazol concentration was 150 mg/L,the output of'Nongda 10' reached its maximum value.In summary,it is of great significance to delay the millet senescence by spraying appropriate concentrations of plant growth regulators in the appropriate growing season in late ripening millet areas in Shanxi.