Effect Of Drought And Low Temperature Stress On Physiological Characteristics And Quality Of Polygonatum.sibiricum Red

In order to explore the infulenceof the growth and active consitituents of Polygonatum.sibiricum Red in different soil moisture(suitable moisture 75% ?f,moderate drought 50% ?f and severe drought 35% ?f)under antioxidant properties,dry matter and P.sibiricum Red of accumulation law polysaccharide research,with a view to P.sibiricum Red of standardized planting in the field of water management to obtain suitable P.sibiricum Red growth soil moisture conditions;and under low temperature stress on five areas(Yaan,Sichuan,Shaanxi Lueyang,Zhejiang Xianju,Henan Song County,Henan Lingbao)physiological changes Polygonatum do the research in order to provide a theoretical basis for the anti-spring cold spell management.The main conclusions are as follows:1.P.sibiricum Red.seedlings can adjust the growth,dry matter accumulation and Sibiricum,anti-oxidative activity and photosynthesis Sibiricum solution to adapt to water stress.Under three water treatments,P.sibiricum Red.seedlings morphological indicators(plant height,stem diameter,leaf length and leaf width,the new root diameter,root length new,long fibrous roots,ground and underground parts of fresh and dry weight)showed a "S" growth trends,significant differences among the treatments.Moderate water stress is more conducive to the accumulation of the yellow substance capable of.At a growth stage,suitable for water,moderate water stress and severe water stress,root dry matter accumulation reached0.74 g,1.39 g and 1.16 g,than the initial growth increased by 262.50%,363.33% and 544.44%.Accumulation of Sibiricum emerged was also found "S" growth trend,but in the end there is a slight decline in growth.In early August to late mid-September under moderate water stress and severe water stress,accumulation of magnitude higher than Sibiricum moderate water stress large,therefore,in the field experiment,consider Sibiricum accumulation period,control of soil moisture conditions in order to increase the content of Polygonatumpolysaccharide.Water stress can increase the in vitro Sibiricum aqueous solution of antioxidant capacity.Under conditions of severe water stress,P.sibiricum Red.polysaccharide aqueous solution of DPPH radical scavenging capacity of the strongest,and the ability to clear differences in the other two moisture conditions Sibiricum solution significantly.Under different water conditions,net photosynthetic rate,changes of stomatal conductance and transpiration rate and instantaneous water use efficiency P.sibiricum Red.seed is basically the same,showed a clear bimodal curve,and a "midday depression." In the process of photosynthesis daily variation,suitable for under water stress,the net photosynthetic rate,stomatal conductance and transpiration rate is high,and there are significant differences with the other two water stress,and the next three moisture conditions,P.sibiricum Red.seed instantaneous water use efficiency were significantly different(50% ?f> 35% ?f> 75% ?f).Under moderate and severe water stress,photosynthesis P.sibiricum Red.seedlings decreased significantly.Compared with moderate moisture content level Polygonatum total chlorophyll decreased by 50.09% and 61.20%,significantly affected the accumulation of yellow fine seed in photosynthetic products.Various water treatments carotenoid(Car)contents were significantly different.Moderate and severe water stress than under normal water conditions,respectively,compared an increase of 21.16% and 54.29%.2,Polygonatum Mill low temperature stress on growth,development and survival will be severely affected.With the increase of stress time,Polygonatum Mill seedlings from different regions of the leaf soluble sugar content increased first decreased,while soluble protein and free proline content decreased first increased and then decreased it was.After 4 h at low stress soluble sugar,soluble protein and free proline content reached the minimum value,maximum and minimum values,indicating that low temperature stress 4 h key point Polygonatum Mill seedlings physiological indices of detached leaves of the response.Polygonatum Mill seedling leaves in vitro in the early cold stress membrane lipid oxidation severity was significantly increased content of MDA,with the extension of post-stress time,leaves MDA content decreased,decrease in membrane lipid peroxidation.Polygonatum Mill from Shaanxi Lueyang MDA content in leaves throughout the process has always been low temperature stress decreased.This suggests that local Lueyang Polygonatum Mill after long-term evolution and adaptation,through self-regulatory mechanisms to reduce cold stress on their own damage.Photosynthetic characteristics of soil drought on yellow fine,chlorophyll content and stilbene bitterness acyl radical(DPPH)clearance: Polygonatum Mill under different soil moisture conditions,the net photosynthetic rate(Pn),stomatal conductance(Gs),transpiration rate(Tr)and instantaneous water use efficiency(WUEi)variation is similar,itshowed a bimodal curve,noon obvious midday depression.Pn,Gs and Tr performance throughout the diurnal changes of photosynthetic process is: 75% ?f> 50% ?f> 35% ?f,suitable water treatment and the other two deal with significant differences;WUEi showed50% ?f> 35% ?f> 75% ?f,a significant difference between the three.With increased levels of stress,chlorophyll content decreased,compared with the appropriate water subphase,drought and moderate drought and severe chlorophyll content decreased by 61.20% and 50.09%,the chlorophyll content of the performance: 75% ?f> 50% ?f> 35 % ?f,appropriate moisture exist significant differences with the other two processes.Various water treatments carotenoid(Car)content level showed 50% ?f> 35% ?f> 75% ?f,the difference between the water treatment significantly.With the next three water treatments rhizome extract concentration increased antioxidant capacity enhancement solution of DPPH radical scavenging rate continues to increase,severe drought stress compared with the other two moisture on DPPH radical scavenging variation margin,the difference was significant,DPPH radical scavenging ability showed 35% ?f> 75% ?f> 50% ?f.Polygonatum Mill able to regulate the growth,photosynthesis and content of the anti-oxidizing substance to adapt to drought stress.