Effects Of Spraying With Spermine On Physiological Characteristics And Yield Of Foxtail Millet During Filling Stage

In order to investigate the effects of exogenous spermine on Physiological Characteristics and Yield of Zhangza 10 and Jingu 21 during Filling stage.and the optimum concentration about effect of yield of millet was screened out. the experiment used the randomized block design through spraying spermine of different strengths (0,0.1,0.5,1,1.5 mmol·L-1) in grain filling stage and In the field experiment. The photosynthetic pigment content, photosynthetic parameters, chlorophyll fluorescence parameters, protective enzyme activity, MDA content, carbon and nitrogen metabolism and grain filling rate,ear diameter,1000-grain weight and yield was determined.The main findings as follows:1.Foxtail millet was treatmented by spermine of different concentrations,Chla, Chlb and Chl(a+b) were showed a trend of increasing at first and then decreasing with the increase of spraying spermine concentrations.and effect is best when the concentration was 1.0 mmol·L-1. But Car had benn increasing with the increase of the concentration of spermine. The chlorophyll a, chlorophyll b, total chlorophyll and carotenoid were significantly higher than the blank after the treatment.and the impact with the extension of the time is still significant.2.The net photosynthetic rate (Pn), transpiration rate (Tr) and stomatal conductance (Gs) were increased in the leaves of two kinds of millet after grain filling stage of spraying spermine, which was significantly higher than that in control group.They showed a single peak trend with the concentration of spermine. effect is best when the concentration was 1.0 mmol·L-1 and this effect is still significant with the development of growth period. But the intercellular CO2 concentration (Ci) showed the first decreased and then increased with the increase of the concentration of treatment, while the concentration of spermine was 1.0 mmol·L-1, the effect is lowest, and the difference was smaller and smaller with the development of the growth period.With the increase of the concentration of exogenous spermine.the maximum fluorescence(Fm), the PS? potential activity (Fv/Fo), maximum photochemical efficiency (Fv/Fm),the actual photochemical efficiency(Y(?)) and electron transport rate (ETR) were significantly increased,but minimal fluorescence(Fo) was decreased. Early FM difference was not significant, and Y(?) differences were not significant throughout the application period about Zhangza 10. About Jingu 21,Fo,Fv/Fo, Fv/Fm and Y(?) are not significantly different at the early stage of the treatment.But spermine and two millet varieties still showed a dose-response relationship,which indicated that the PSII complex of millet leaves was protected under the treatment of spermine, PS ? reaction center much more open, enhancing activity, photochemical efficiency increased, and efficiency which by chlorophyll conversion of light energy into chemical energy would enhance, Finally, it is beneficial to the efficient operation of photosynthesis.3.The protective enzyme activity (POD activity and SOD activity) of Zhangza 10 and Jingu 21 were increased first and then decreased with the increase of the concentration of spermine, the highest activity was highest at 1.0 mmol·L-1, and the difference was still significant with the growth of the growth stage. MDA content was decreased of zhangza 10 after treatment with spermine, About Jingu21, MDA content was decreased first and then increased with the increase of concentration of spermine, and MDA content differences were not significant difference of two kinds of millet at the early stage of the pesticide.4.During grain filling stage, the soluble sugar, soluble protein, nitrate reductase activity and grain filling rate of the leaves increased first and then decreased with the increase of the concentration of arginine. The effect was greatest when the concentration of arginine was 1.0 mmol·L-1, Soluble protein had no significant effect of two millet varieties in the early stage of the application,and grain filling rate in pre application effect is not significant of Jingu 21.5. Different concentrations of exogenous spermine increased the yield of two millet varieties, and with the increasing of concentration of the trend was first increased then decreased.Compared with the blank control, the yield of the zhangza 10 increased by 5.7% to 29.48%, and the yield of the Jin Gu 21 increased by 9.32% to 29.49%.and yield components and yield indicators had roughly the same rule.Spermine changed the grain panicle type, and with the increase of concentration, the ear length variable short, ear diameter, ear weight, ear grain weight and 1000 grain weight were increased gradually, panicle type became tubby and visible when concentration was 1.0 mmol·L-1,effect of the grain yield is the biggest, millet yield would be reduced when the concentration of more than 1.0 mmol·L-1...