Study on the Effect of Oxygen Supply at Rootzone on Improving the Growth Characteristic of Stagnant Water Rape
|School||Hunan Agricultural University|
|Course||Agricultural Soil and Water Engineering|
|Keywords||Oxygen supply to the rootzone Stagnant water rape Growth studies Physiological characteristics|
Rape is one of the major oil-bearing crops in China, and also largely planted in the Yangtze river basin. In the process of planting, rape is both in need of and sensitive to the moisture, especially in the flowering stage. In the most South China areas, the precipitation is sufficient in the whole process of rape growth, and it is more in the flowering stage. More moisture can cause the waterlogging disasters and lead to the inadequate oxygen supply to the rape rootzone, and in this case, rape cannot maintain normal life activities. Therefore, the moisture and oxygen environment of the rape rootzone are the main constraints on its output and quality. The main purpose of this paper is to figure out the influence of the different ways of oxygen supply to the rape rootzone on its growth, characteristics, output and economic indicators in the different stages of its growth. This paper will be studied with the theory and methods of oxygen supply to the rootzone. The result shows that:1. In the different conditions of oxygen supply to the rootzone, as for the perched rape, its leaf area, rootzone length, rootzone volume, rootzone fresh weight, rootzone dry weight, rootzone-shoot ratio, rootzone activity, the total rootzone absorption area and its active absorption area are all increased compared with the contrast group, but its height shows no significant changes. Under the condition of oxygen supply by applying the Hydrogen peroxide solution, the dry weight accumulation of the aboveground perched rape is increased throughout the whole process of growth; but under the condition of oxygen supply by ventilating with fresh air. the superiority is showed in the later period. Thus it can be seen that different oxygen supplies on rootzone can improve the condition of perched rape to some extent, but the most effective method is by applying the Hydrogen peroxide solution.2. Different ways of oxygen supply to the rootzone can promote the photosynthetic rate of the perched rape both in the seeding stage and the flowering stage, and the improvement of the former stage is significantly higher than the superiority of the latter one. The indicators of transpiration rate, stomatal conductivity and intercellular CO2concentration are obviously improved by applying the Hydrogen peroxide solution in the seeding stage, but they are fractionally decreased in the flowering stage. According to the output of the perched rape, the superiority by ventilating with fresh air is showed after the flowering stage. In this way, the oxygen supply to the rootzone is advantageous to the improvement of chlorophyll content, photosynthetic rate, transpiration rate, stomatal conductivity and intercellular CO2concentration to some extent, thereby increasing the output.3. Different ways of oxygen supply to the rootzone can both improve the growth of the perched rape to some degrees, and also increase its output and economic indicators. The improvement of output is more notable by applying the Hydrogen peroxide solution than by ventilating with fresh air to the rootzone, although the latter one is higher than the former one in the respect of the first effective branch number, the number of the siliques on the first grade branch, the length and the silique number of the main raceme. In consideration of the thousand-grain weight, the latter one is lower than the former one. which shows that the latter one is effective on the economic indicators, but not obvious in the improvement of its quality.