Changes Of Physiological Feature To Oryzalin In Root Tips Cells Of Cunninghamia Lanceolata

This article takes primary roots of Cunninghamia lanceolata as the research material, treated them by different concentrations of microtubules interfering drugs Oryzalin. Tracked the morphological changes of root tips, studied the changes in physiological and biochemical indexes such as antioxidant enzymes system, and compared the changes of structure in root tip cells. The main conclusions are as follows:(1) The root tip area of Cunninghamia lanceolata tissue culture seedlings would swell after treated by Oryzalin. And with the increase of concentration and processing time, the degree of swelling is on the rise. Both the root tip area and its epidermal were swelling, but not fracture after treated by Oryzalin in light concentration(1μmol/L). Both the root tip area and its epidermal swelling and not fracture after treated by Oryzalin in middle(10μmol/L) and high(100μmol/L) consistency in 24 h, but will fractured after 72 h. On 72 hours, the root tips showed different degrees of fracture after treated by Orzalin on three kinds of concentration. Relative to the concentration of Oryzalin, the processing time had a greater impact to the swelling degree of epidermal tissue in the root tip area of Cunninghamia lanceolata.(2) There always two nucleolus in root tip cells of Cunninghamia lanceolata. The cells had strong ability of divide in meristem zone were had equal length and width. They had big cell nucleus, many small vacuoles, endoplasmic reticulum, plastids, mitochondria, and their cytoplasm were very thick. The direction of cell division was varied. In the terminal stages of mitotic cells observed centripetal type development of cell plate. After treated by Oryzalin, the morphological structure of root tip cells were destroyed, they were radial expansion, and it’s related to the concentration clasely. On the cellular structure, both the volume of vacuole and the electron density of cytoplasm would increase. Cells in the period of mitotic, had chaotic arrangement of chromosomes, chromosomes didn’t move to the poles during the anaphase, cell plate didn’t form in the cells during telophase, and there were two daughter nucleus in the cell.(3)Based on the observed result of cellular structure and root morphology, we chose the root tips that have treated by middle concentration Oryzalin(10μmol/L) at 2, 8, 12, 24 h to measure the physical signs. We found that the activities of SOD, POD, CAT were raised first and declined later. It reached the highest peak at 2h, and back to the level before treatment after 12 h. We also found that with the increase of concentration and processing time, on the surface of the sample, the content of C and Ca were continue to rise, the content of O was continue to decline. And on the section, the changes of the content of C and O were not obvious; the content of P was continued to rise. The content of other elements has no obvious change rule.