Effect Of Plant Growth Retardants On Germination And Seeding Growth Of Herbaceous Seeds In Sloping Greening

Herbs can stabilize a large number of exposed slopes which were produced by construction of roads,railways and mines and other projects as well as improve their ecological environment.Compared with the shrub seeds,the herbaceous seeds germinate faster,grow faster and are more competitive in herb-shrub mixed type which is the target community in the slopes greening.Therefore,it is necessary to carry out the study of plant growth retardants to inhibit the germination of herbaceous seeds and seedling growth.In this paper,Astragalus adsurgens Medicago sativa and Festuca arundinacea were test materials,and were soaked in different concentrations of chlormequat,paclobutrazol and uniconazole solution or soaked with chlormequat,paclobutrazol and uniconazole solution in different hours.As well as sprouting herbaceous plant with different concentrations of plant growth retardants.And then observe the germination potential of three herbs,their effects of radicle and embryo growth and the growth of herbaceous seedlings.The results show:(1)The inhibitory effect of paclobutrazol on the germination potential of three herbs was significant.Chlormequat and uniconazole solution reduced the ratio of germ length of Astragalus adsurgens and Medicago sativa,and increased the ratio of radicle length.And the higher the concentration of chlormequat solution,the stronger the inhibitory effect on the length of their embryo.The germination potential of the three herbaceous seeds was inhibited by the 380-420mg/L paclobutrazolone solution.The germination potential of Astragalus adsurgens,Medicago sativa and Festuca arundinacea was inhibited by 500 mg/L uniconazole solution.(2)From the cumulative emergence,chlormequat and paclobutrazol solution can effectively reduce the emergence rate of Astragalus adsurgens.The soaking solution of uniconazole solution can effectively reduce the cumulative emergence number and height of Medicago sativa.Due to chlormequat and uniconazole solution,the time of emergence of Medicago sativa and Astragalus adsurgens was delayed,and the common concentration was:chlormequat 500mg/L and uniconazole 500mg/L.(3)With the increase of the immersion time of the uniconazole solution and the paclobutrazol solution,the greater the inhibition degree of the height of Festuca arundinacea.Combined with the emergence rate and germination potential,the optimal immersion time is 12h.The herbaceous seeds were treated with uniconazole 500mg/L.solution and then mixed with shrub seeds.The effect of inhibiting the growth of herbaceous plants was realized.The effect of the usage of plant growth retarder in a large area of slope greening is unclear,need to combine a large number of field rials.Therefore,three plant growth retardants inhibited the germination of three herbaceous seeds which can provides reference index for plant growth retardants to treat herbaceous seeds in slopes greening.