Effects Of Different Plant Growth Regulators On The Growth And Development Of Maize (Zea Mays L.)

Field and pot experiment was conducted in 2008 and 2009 to investegate the effects of seed dressing with 3 plant growth regulators and their compounants on maize roots, stem and leaves of the elite hybrid ZhengDan958(ZD958). The results were as follows:1 The effects of different plant growth regulator on maize seedling gemination and growthThere were positive effect of seed dressing on maize seedling gemination and growth of all the plant growth regulators used in this experiment. Theα-amylase activity and soluble sugar contant of each treatment were all higher than the control. The improvement ofα-amylase activity and soluble sugar contant provided a basic foudamental for high and stable yield by improving the seedling gemination process, gemination vigor and rate, prolonged field growth period,2 The effects of different plant growth regulator on maize root growth and physiological characterRoot growth was significantly improved by seed dressing with the plant growth regulators used in this experiment. Root of the seed dressing was much bigger, and its vigor was higher than the control. During the later growth period, the POD activity of the treatment was higher than the control, which could delay root senescence and improve the ability of root absorption, synthesis and the nutrition transportance to the shoot. Root growth became more healthy and is positive to grain filling during the late growth stage.3 The effects of different plant growth regulator on maize leaf growth and physiological characterLeaf area index (LAI), chlorophyll a, chlorophyll b, chlorophyll (a+b) and carotenoid content were increased by seed dressing with the plant growth regulators used in this experiment, which could improve the ability of maize photosynthetic pigment to absorb and transform light energy. At the same time, maize leaf anti-oxidation enzyme, such as SOD and CAT, were increased by seed dressing by the plant regulators used in this expriment, which reduced the accumulation of reactive oxygen species(ROS) contents, repressed the peroxidation of lipid membrane, and improved the stress-resistance ability, with E treatment was the best one and G treatment took the second place. 4 The effects of different plant growth regulator on maize dry matter accumulation and translocationThe translocation and translocation rate of the dry matter from other organs to kernal were increased significiantly by proper plant growth regulator combination. The translocation from stem to kernal was the highest, followed by leaf and sheath. The contribution ratio of different organ to kernal was similar to translocation. proper plant growth regulator combination provided a basic foudamental for high and stable yield by increased the dry matter accumulation and translocation to kernal.5 The effects of different plant growth regulator on maize yieldEar charactors were improved and yield was increased by all the plant growth regulators.Used in this experiment, and the combination treatments were better than the single treatmen. The yields of E and G treatment were significiently higher than single treamtment and the control (P<0.05) by 905.829kg/hm~2 and 802.400kg/hm~2, respectly, with the increase rate by 9.93% and 8.80%, respectly.