Effect Of Ecological Factor On The Concentration Of Terpenoid In Tobacco

Terpenoids are primary substances in plant secondary metabolism, which play an important role in the process of plant growth and development. The biological activity of terpenoids are varied because they are wide range and varied in nature.With the development of science in recent years, terpenoids have been widely used in the new drugs, antibiotics, pesticides, herbicides et al as an important material. Terpenoids play a huge role in the agricultural production process, so it's significant to research the biosynthesis and synthesis of mechanisms of terpenoids for better use. Metabolism in plants is decised by its own gene, but also by the surrounding ecological factor which includes light, temperature, moisture, air, inorganic salts and so on. The changes of ecological factors affect the expression of different genes and different gene products affect the structure of plants or regulate the activity of enzyme directly. The thesis research the influence of light intensity, light quality, mineral nutuition on the content of solanesol and leaf structure in tobacco, details are as follows:The tobacco were shading with different shading net and the results showed that the strength of illumination influence the metabolism of solaneslo and the structure of leaf, the solanesol concentrations in shading tobacco are lower than the control group, the two-layer are lower than the one layer; the upper and lower epidermal cells of tobacco in shading are smaller than the control group, the leaves were thinner than the control group, the palisade and spongy tissue are looser than the control and the ratio of palisade tissue came down.The tobacco were treated with UV-B, blue light, red light and natural light, the results showed that different wavelengths influence the metabolism of solaneslo and the structure of leaf, the content of solanesol in tobacco with appropriate UV-B increased and the content of solanesol with blue light and red light wasn't significant; the leaves become thinner with blue light and red light,and the thickness and ratio of the palisade tissue come down than the control group. The cells in tobacco leaves with UV-B were tight, there was little spongy tissue in leaves. The palisade tissue was the main place to synthesis solanesol. The change rule of the structure and thickness of palisade tissue was consistent with the content of solanesol in tobacco.The tobacco were treated with different concentrations of lanthanum nitrate and cerium nitrate, the results showed that the right amount of rare earth elements can make the cells in leaves tight and make the palisade thicker and promote the synthesis of solanesol and improve the content of solanesol in tobacco leaves. But high concentrations of rare earth elements can suppresse the synthesis of solanesol. When the concentrations of lanthanum between 100-300μmol/L and the concentrations of cerium between 300-500μmol/L, the solanesol in tobacco can increase. As for the molecular mechanism in the metabolism of tobacco with different factors needs further study...