The Effects Of Different Eucalyptus Special Fertilizers On The Growth, Physiology Biochemistry Of Eucalyptus Trees And Seedings Under Drought Stress

As an industrial timber, Eucalyptus occupies an important position in our country and some of the other countries. Due to its fast growth, strong adaptability, it becomes one of the popular tree species in southern China, especially in Guangxi. Guangxi has become an important strategic industrial timber forest base of China with eucalyptus mainly grown During the12th Five Year Plan Period, The timber output in this region will take up17%of the total timber output of China. And then, eucalyptus cultivation measures will be improved and strengthened, and the influence of the bad environment on the growth of eucalyptus will be dealed with. Through potting drought stresses and woodland experiment, we used four different eucalyptus special fertilizers (steam fertilizer, coating fertilizer, sulfate fertilizer, special compound fertilizer produced by a forestry center) and active fertilizer in cultivating E.urophylla×E.grandis DH32-29. Relevant growth and physiological and biochemical indexes were measure so as to guide the production and operation of eucalyptus, and promote its productivity and the sustainable development of eucalyptus industry. The main results were as follows:1. Under drought stress, the influence size order of eucalyptus ground diameter, root/stem/total fresh weight, and root/stem/total dry weight among the three different fertilizers is steam fertilizer> coating fertilizer> sulfate fertilizer. The influence size order of eucalyptus seedling height, leaf area, branches and leaves fresh weight and dry weight is sulfate fertilizer> steam fertilizer> coating fertilizer. Different eucalyptus special fertilizers changed the distribution of organic matter in eucalyptus seedlings, with proportion of leaves and stems of eucalyptus DH32-29seedlings increased and the plant roots reduced. Application of the three fertilizers with active fertilizer can effectively promote ground diameter, seedling height, leaf area, total/root/stem/leaf fresh weight and root/stem/leaf/total dry weight.2. Under drought stress, the influence size order of eucalyptus leaf chlorophyll content among the three different fertilizers is steam fertilizer> sulfate fertilizer> coating fertilizer.The influence size order of the activity and proline content of eucalyptus leaf SOD is coating fertilizer> steam fertilizer> sulfate fertilizer. Application of different fertilizers with active fertilizer can effectively promote the chlorophyll content and SOD activity, which promotes the transformation of the organic material of the seedling, lowers the content of leaf soluble sugar and proline, and promotes the the adaptation of eucalyptus to the drought environment.3. Under drought stress, different eucalyptus specific fertilizers are different in nutrient releasing mechanisms. The influence size order of eucalyptus leaf N, P, K content among the three different fertilizers is sulfate fertilizer> steam fertilizer> coating fertilizer. The influence size order of potted eucalypt soil N, P content is coating fertilizer> steam fertilizer> sulfate fertilizer. The influence size order of potted eucalypt soil K content is coating fertilizer> sulfate fertilizer> steam fertilizer. Application of active fertilizer with different fertilizers effectively reduce the soil N, P, K content, increased the content of leaf N, P, K, and promoted to the absorption of N, P, K nutrient elements.4. The test results of different Eucalyptus special fertilizers on the eucalyptus forest show that:steam fertilizer is more advantageous to the height growth of E. urophylla×E.grandis DH32-29trees, and coating fertilizer can effectively promote the DBH growth. The applying content of steam fertilizer is750g per plant for the eucalyptus DH32-29trees. The effect of inorganic fertilizer can be strengthened by increasing active fertilizer, which can promote eucalyptus forest tree height, DBH and volume, and the improvement of economic benefits.5. All in all, both different fertilizers and soil moisture environment have significant impact on inorganic fertilizer, and have different impact on the growth of E.urophylla×E.grandis DH32-29. Different fertilizers added by active fertilizer can promote the effect of inorganic fertilizer, and the growth of eucalyptus both in drought stresses and in woodland.