Study Of Quinclorac On The Physiological Characteristics Of Flue-cured Tabacoo

Based on laboratory test and experiments in potted, studied different concentrations of quinclorac on seed germination, leaf and root physiological and biochemical indices, leaves and roots of Endogenous Hormones,lhotosynthetic characteristics, chlorophyll fluorescence,leaf ultrastructure and SNP effect on the repair of tobacco and tobacco leaf quality. The results are as follows:1. Effects of quinclorac on flue-cured tobacco seed germination and seedling growth.With the quinclorac concentration, flue-cured tobacco seed germination, germination index, and vigor index decreased, and the significant difference, while the germination rate of flue-cured tobacco had no obvious effect; seedling height and root length are reduced, the fresh weight and dry weight decreased, soluble protein content decreased; Tobacco in peroxidase (POD) activity increased, superoxide dismutase (SOD), catalase (CAT) activity decreased, ? OH-, O2 ? - and MDA content increased.2. Study on quinclorac harm threshold of flue-cured tobacco.Quinclorac on the length of leaf width and smoke are inhibited, but inhibitory effect on leaf length (22.25%) less than the width of the inhibition of the leaf (57.10%), in low concentration 1.00×10-2mg/kg , little difference compared with the control. With the increase of concentration, MDA, proline, soluble sugar content increased.In short, quinclorac concentration of 1.00×10-2mg/kg when tobacco leaf width, leaf length, plant height and number of physiological indicators of performance are no major differences with the control, we set the concentration of two Chlorine quinolinic acid on the dangers of tobacco threshold.3. Effects of quinclorac on the physiological characteristics of flue-cured tobacco.With quinclorac treatment SOD, POD, CAT and APX activity were lower than the control. Leaves and roots of ? OH-, O2 ? - and MDA content were consistent with the time and the concentration increases, the content increased. Quinclorac treatment, with the increased concentration of leaf and root protein, nucleic acid, RNA and DNA levels were reduced.Quinclorac treatment, with the concentration increased leaf and root in IAAO activity increased. After quinclorac treatment, ATP activity were increased firstly and then decreased, and the activity is less than the control. Invertase activity in leaves and roots, with the growth period decreased activity is less than the control. NR in leaves and roots decreased activity, and are less than the control.Quinclorac treatment of tobacco plants, leaves and roots of IAA, GA3 and ZR contents were lower than the control, while the ABA content lower than the control.Quinclorac treatment, all treatments Fv / Fm values are less than the control; leavesΦPSII showed an increasing trend, but after quinclorac treatmentΦPSII increased slowly, and are less than the control; photochemical quenching ( qP) at first increased and then decreased, and qP values are lower than the control. Chlorophyllase activity, with the concentration increases. Quinclorac treatment, the leaf photosynthetic rate, transpiration rate, stomatal conductance and intercellular CO2 concentration were significantly lower.4. Effects of quinclorac on morphology and ultrastructure of leaves of flue-cured tobacco.Victims of the flue-cured tobacco on the skin thickness, the thickness of the lower epidermis, palisade width, thickness of spongy tissue, vein area, perimeter than normal leaves large, the normal vascular area ratio larger than normal vascular circumference larger area than normal marrow, big pulp circumference than normal. Victims of flue-cured tobacco stems thicker than normal epidermal thickness, thinner than normal cortical thickness, vessel diameter, smaller than normal, marrow area than the normal small, smaller than normal circumference. Hazards of tobacco roots are the same with normal shape .Quinclorac stress, the tip cell wall by electron microscopy, lipid membrane, cytoplasm, vacuole and other organelles dysplasia; in the leaves, grana, outer membrane, lamellar structures severely damaged, some cells mutate.5. Effects of different concentrations of SNP on quinclorac of flue-cured tabaccoSpraying leaves of SNP to reduce superoxide anion radical (O2 ? -), hydroxyl radical (? OH-) and malondialdehyde (MDA) content, but also increase the content of superoxide dismutase (SOD), catalase (CAT) and ascorbate peroxidase (APX) activity; 0.01mmol / L concentration of SNP the most obvious effect of the restoration.6. Effects of quinclorac on the quality of flue-cured tobacco leaves The flue-cured tobacco leaves of total sugar, reducing sugar, total nitrogen, protein, potassium quinclorac treatment with increasing concentration the contents decreased in comparison with the control reached a significant level; and starch content of nicotine increases with increasing concentration. After SNP sprayed, the appropriate level of the indicators shows that SNP can relieve quinclorac on tobacco's harm, serve to improve the quality of the effect of tobacco...