| Objective: Study on the regulation mechanism of endogenous hormones in Acanthopanax giraldii Harms under deforestation and shading to reveal the relationship between endogenous hormones and the growth of Acanthopanax giraldii Harms.To study the effects of different fertilizers and plant growth regulators on the growth of Acanthopanax giraldii Harms seedlings,in order to increase the efficiency of Acanthopanax giraldii Harms.Methods: The cultivated plants of Acanthopanax giraldii Harms,which had been cultivated for 5 years,were used as the research objects.The harvesting interference group and the shading interference group with different intensities were set up.The growth parameters such as growth height,number of new shoots,length of new shoots,number of new shoots of Acanthopanax giraldii Harms in different periods were measured.The contents of endogenous hormones ABA,IAA,iPA,ZR and GA in the parietal and lateral leaves of different growth stages were analyzed by ELISA.The effects of cutting and shading on endogenous hormones and the relationship between endogenous hormones and growth parameters were analyzed.In addition,different plant growth regulators and fertilizers were selected to treat the cutting seedlings,annual cuttings,two-year cuttings,and annual seedlings.The growth indexes such as root area,root growth,growth plant height,and number of new shoots were counted in the corresponding groups.The effects of different plant growth regulators and fertilizers on the growth of Acanthopanax giraldii Harms were analyzed.Results:(1)Analysis of the effects of different cutting intensity on endogenous hormones and growth response: The total number of new branches,the total length of new branches and the highest plant height in the light cutting group and the uncut group were significantly higher than those in the heavy cutting group(P<0.05).The total length and the highest plant height of the light cuttingt group were higher than that in the uncut group,and the number of new sprouting branches in the heavy cutting group and the light cutting group was higher than that in the uncut group.The trend of hormonal changes in Acanthopanax giraldii Harms was similar.After the felling in May,by the end of June,the IAA in the plant changed.After logging,IAA content decreased,and then IAA/ABA showed an upward trend.Until the end of June,the top leaves of the light cutting group were significantly higher than the uncut group(P<0.05),and the top leaves of the heavy cutting group were also higher than the uncut group.This stage was also the fastest growing stage of growth factors of Acanthopanax giraldii Harms,suggesting that auxin IAA was closely related to plant growth,and had the effect of promoting new shoot germination and new branch elongation after felling.In addition,under the heavy and light cutting,the content of iPA and GA also increased,the decrease of ZR was higher than that of the uncut group,the ratio of iPA/ABA and GA/ABA increased,and the decrease of ZR/ABA was greater than that of the uncut group,suggesting that GA and iPA also promote the growth of plants,but ZR was greatly affected by the outside world,which may interfere with the pathways it generates.According to the analysis,the related growth factors of the heavy cutting group were lower than other groups because the excessive deforestation destroys its vegetative organs,which made it difficult for plants to restore the physiological functions of vegetative organs in a short period of time.(2)Analysis of effects of different shading intensity on endogenous hormones and growth response: The total length and total number of new branches in the unshaded group were higher than those in the light shade and moderate shade group,and the light shade was higher than the moderate shade.The highest plant height of the moderate shade group was higher than that of the light shaded and unshaded group.From July 15 th to July 31 st,the content of ABA,IAA,iPA,ZR and GA in the parietal lobe and lateral lobe of Acanthopanax giraldii Harms increased under moderate shading and mild shading.the values of IAA/ABA and GA/ABA in the lateral lobe decreased,and the values of iPA/ABA in the parietal lobe and lateral lobe increased.It was higher than the unshaded group on July 31.Under moderate shade,the growth hormone content of the leaves of Acanthopanax giraldii Harms decreased less than that of light shade,and the increase of iPA/ABA was greater than that of light shade.In addition,the value of GA/ABA in the parietal lobe under moderate shading increased.Since the shading time of this study was short,there was no significant change.According to the analysis,the ratio of many growth-promoting hormones and abscisic acid decreased,because the growth intensity of Acanthopanax senticosus was inhibited when the shading intensity was high,and the plant itself developed in the direction most favorable to its own growth,and the abscisic acid content in the body increased.To promote the closure of the stomata,to a certain extent reduce the energy consumption and enhance the plant's resistance.The increase in the content of GA was that under shading conditions,plants should look for more sunlight,and gibberellin can promote the elongation of branches.(3)Effects of different growth regulators and fertilizers on seedling growth: Shading treatment can improve the survival rate of cutting seedlings in the same year.After soaking for four hours in 200mg/kg hormone 2,the cuttings will be built and the survival rate will be 69%.Urea point application can promote the elongation growth of new shoots or new shoots of annual seedlings.The root area,the number of lateral roots,the root growth score,and the total score were used to establish the measurement index.Studies have shown that the spraying of 20mg/L hormone 5,hormone 7,hormone 8,100mg/L hormone 6 and 10mg/L hormone 7 and hormone 8 on the leaf surface can promote the growth of primary lateral roots of annual cuttings;12 Foliar spray application has different degrees of inhibition on the growth of annual roots of cutting seedlings.GF-1,3,4,8,10,11,12 can promote the growth of primary roots,GF1 has the strongest effect;For the annual sprouting seedlings,the effects of new shoots or new shoots are stronger than the four fertilizers.Conclusion: Light cutting promotes the growth of Acanthopanax giraldii Harms,which inhibits its growth by shading and heavy cutting.IAA/ABA plays an important role in its growth.Heavy cutting destroys its vegetative organs,making it difficult for plants to restore the physiological functions of vegetative organs in a short period of time.When the shading intensity is large,the relative content of abscisic acid in the plant will increase significantly,and the plant resistance will be improved.The hormone 2 soaked in the cuttings and the construction of the shading net significantly improved the survival rate of the Acanthopanax giraldii cuttings.Some plant growth regulators and fertilizers promote the growth of lateral roots but fail to promote root growth. |
PDF Full Text Request