Effects Of Synergistic Treatment Of Substrates And Shade On The Morphological Plasticity And Physiological And Biochemical Of Zoysia Sinica

Heterogeneity of substrate and shading often leads to lawn different performance at transitional climatic zone, including establishment speed, coverage, density, biomass structure, turf quality, community structure and lawn lifetime, etc.. In view of the above problems, Zoysia sinica as a test material was planted into pots. These pots were artificially set to five kinds of substrate( purple soil, humus soil, coarse sand soil,residual soil after construction, and stony soil)and five shading gradients. After cuttage propagating into lawn, some indicators, such as cuttings survival rate, seedling components, biomass accumulation, growth characteristics, physiological and biochemical characteristics, etc. were determined. The synergistic effect of substrate and shading on Z. sinica and stress mechanism and adaptation strategy of Z. sinica to the synergistic effect were analyzed. The purpose is to provide technical guidance for selecting substrate and formulating maintenance measures during establishing and maintaining Z. sinica lawn and provide scientific basis for lawn landscape construction and improvement. The results showed as follows:(1)Effect of soil substrate on survival rate and growth of cutting seedlingsSubstrate had a significant influence on survival rate and germination index(P<0.05). After 30 days, bud length showed a highly significant difference(P<0.01).Especially, survival rate and germination index in the stony soil;(S5)were significant higher than those of other substrates(P < 0.05). Substrate had a significant influence on root and stem traits of cutting seedling(P<0.05), but a little influence on leaf trait.Substrate both had significant effects on underground and aboveground biomass of seedling( P < 0.05), and extremely significant effect on the root-stem ratio and underground biomass ratio(P<0.01). Purple soil was conducive to the formation of seedling tiller, and residual soil was beneficial to the growth of stem and biomass allocating to aboveground part. Yet the application of stony soil made biomass transport to underground part.(2)Effect of soil substrate and shading on seedling component and biomass allocationSubstrate had a highly significant influence on survival rate, component traits andbiomass allocation, and in which the substrate sequence beneficial to Z. sinica survival and growth was purple soil> residual soil after construction> coarse sand soil> stony soil>humus soil. Shade degree had a highly significant influence on survival rate, and about 30% shading was beneficial to survival and growth of Z. sinica. The interaction of soil substrate and shade degree had a significant influence on component traits and biomass allocation of seedlings. Substrate was the main factor, followed by shade degree. Influence order of soil substrate and shading synergistic effects on component biomass allocation was ranged as leaf> root> stem. Z. sinica would improve the adaptation and chilling resistance by adopting corresponding morphological plasticity and growth strategy based on its soil substrate and shade degree.(3)Effect of substrate and shading on physiological and biochemical characteristicsSubstrate had no significant effect on osmotic substances, free proline and soluble protein of Z. sinica, and significant impact on other physiological and biochemical substances. And the order of influence was photosynthesis> oxygen metabolism >penetration mechanism. Purple soil has good resistance. Shading had highly significant effects on physiological and biochemical substances on Z. sinica.Under the condition of about 30% shading, Z. sinica populations revealed best shade tolerance, Serious shading critically affected normal regulation of plant. The interaction of substrate and shading had highly significant effect on physiological and biochemical substances of Z. sinica. in which greatest effect was content of chlorophyll maximum.Especially, shading was main effect, followed by substrate. The synergistic effect of substrate and shading on physiological and biochemical substances was ranged as chlorophyll > photosynthetic parameters> oxygen metabolism> permeation mechanism.Obviously, synergistic reaction of substrate and shading directly affected the photosynthetic capacity of plants.In short, stony soil(S5)was in favor of survival of Z. sinica cuttings, and purple soil(S1)was beneficial to tiller of cutting seedlings. Z. sinica planted into these substrates except for humus soil(S1) all showed good performance under the condition of 30%shading, with higher morphology, physiological and biochemical indexes. But Z. sinica planted into humus soil under the different shading degree all did not show a goodperformance. Thus turf grass was planted into humus soil, local mature soil should be mixed to reduce content of organic matter. When shade degree was more than 30%, turf in several substrates all were poor. It showed that deep shade seriously affected normal growth and development of plants. Therefore, planting turf should try to avoid the environment, in which shading was too much.