草舒对尾巨桉幼苗生长及生理的影响

发布时间：2018-06-04 10:43

本文选题：尾巨桉 + 除草剂　；参考：《广西大学》2017年硕士论文

【摘要】：桉树是广西主要人工林树种,种植面积居全国首位。在桉树生产经营中,幼林人工抚育是一项繁重的工作。应用化学除草剂除草具有省工、省时、投入少、收益大等诸多优点,但是在除草剂的喷施过程中,漂移、飞溅的雾滴不可避免地要接触到苗木,使非目的树种受药害。本研究通过模拟除草剂喷施应用实践中产生的除草剂漂移、飞溅量,研究除草剂草舒对桉树幼苗生长指标和生理指标的影响,为桉树林地科学使用除草剂、完善桉树化学除草技术提供科学依据。主要研究结果如下:1.不同浓度(0.046%～0.32%)的除草剂草舒处理均对尾巨桉幼苗产生药害,药害等级和药害指数均随着除草剂草舒浓度的增加而不断升高。2.草舒对尾巨桉幼苗的高生长和根系生长有显著的抑制作用。具体表现为抑制尾巨桉幼苗根系的伸长生长和抑制根系表面积和体积的增加。喷施草舒后,尾巨桉幼苗的根尖数明显减少。3.草舒处理降低尾巨桉幼苗的生物量和含水量。随着草舒处理浓度的升高,尾巨桉幼苗根、茎、叶的生物量和含水量均出现下降的趋势。其中,尾巨桉幼苗叶片含水量的降低达到显著水平(P0.05)。4.草舒处理降低尾巨桉幼苗叶绿素含量,抑制光合作用的进行。随着草舒处理浓度的升高,幼苗净光合速率和蒸腾速率明显下降,而胞间C02浓度明显升高,光合作用C02同化明显受阻。5.草舒处理后巨桉幼苗的可溶性糖含量显著高于对照(P0.05),可溶性糖含量随着草舒处理浓度的增加呈现先升高后降低的趋势。尾巨桉幼苗可溶性蛋白含量也随着草舒处理浓度的增加而升高,其中,经过稀释300倍和稀释100倍的中高浓度草舒处理后巨桉幼苗的可溶性蛋白含量显著高于对照(P0.05)。6.尾巨桉幼苗的细胞膜透性和丙二醛含量随着草舒处理浓度的增加而升高。草舒处理后尾巨桉幼苗的细胞膜透性显著高于对照(P0.05)。7.草舒处理对尾巨桉幼苗保护酶活性有显著的影响,酶活性均呈现出先显著升高后显著降低的变化趋势。其中,稀释700倍浓度的低浓度草舒处理的POD、SOD和CAT等保护酶活性显著高于对照(P0.05)。
[Abstract]:Eucalyptus is the main artificial forest species in Guangxi, and its planting area ranks first in China. In the production and management of eucalyptus, artificial tending of young forest is a heavy work. The application of chemical herbicide herbicides has many advantages, such as saving labor, saving time, less investment, large profit and so on. However, in the spraying process of herbicide, drifts and spattering droplets will inevitably come into contact with seedlings, and the non-target species will be harmed by medicine. In this study, the effects of herbicide on the growth index and physiological index of eucalyptus seedlings were studied by simulating the herbicide drift and spatter produced in the practice of herbicide spraying, and the herbicide was used scientifically in eucalyptus forest land. To improve the chemical herbicide technology of eucalyptus to provide scientific basis. The main results are as follows: 1. The herbicide Caoshu with different concentrations (0.046 and 0.32) all caused damage to the seedlings of Eucalyptus grandis, and the damage grade and index increased with the increase of the concentration of herbicide Caoshu. Saoshu had a significant inhibitory effect on the height growth and root growth of Eucalyptus grandis seedlings. The results showed that the growth of root system and the increase of root surface area and volume of Eucalyptus grandis seedlings were inhibited. The number of root tips of Eucalyptus grandis seedlings decreased significantly. The biomass and water content of Eucalyptus grandis seedlings were decreased by the treatment of Zaoshu. The biomass and water content of root, stem and leaf of Eucalyptus grandis seedlings decreased with the increase of the concentration. Among them, the decrease of water content in leaves of Eucalyptus grandis seedlings reached the significant level of P0.050.4. Chlorophyll content of Eucalyptus grandis seedlings was decreased and photosynthesis was inhibited by Caoshu treatment. The net photosynthetic rate and transpiration rate of seedlings decreased obviously with the increase of the concentration of Caoshu, while the concentration of C02 in the intercellular increased obviously, and the assimilation of photosynthesis CO2 was obviously blocked. 5. The soluble sugar content of Eucalyptus grandis seedlings was significantly higher than that of the control (P0.05N), and the content of soluble sugar increased first and then decreased with the increase of the concentration. The soluble protein content of Eucalyptus grandis seedlings also increased with the increase of the concentration of Herba Shu, and the soluble protein content of Eucalyptus grandis seedlings treated with 300 times dilution and 100 times dilution was significantly higher than that of the control. The cell membrane permeability and malondialdehyde content of Eucalyptus grandis seedlings increased with the increase of the treatment concentration. The cell membrane permeability of Eucalyptus grandis seedlings treated with Caoshu was significantly higher than that of the control. The protective enzyme activity of Eucalyptus grandis seedlings was significantly affected by Caoshu treatment. Among them, the activities of POD SOD and CAT in low concentration Caoshu treated by diluting 700 times concentration were significantly higher than those of the control P0.05.
【学位授予单位】：广西大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：S792.39;S765

【参考文献】