Study On The Effects Of Organic-inorganic Mixed Fertilizer On The Growth And Soil Nutrient Contents Of Sugarcane

Sugarcane is the most important sugar crop and takes for more than 90 percent of sugar product in mainland China. At the same time, sugarcane is one of the most important bioenergy crops. With a good stress resistance, sugarcane is widely cultivated and a dapted to many different soils. In order to gain a stable and high production, it is necessary for cultivation of soil productivity, and then a good quality soil condition will be provided. Focused on the problems of soil acidification, descendent fertility, sandy soil and over usage of chemical fertilizer especially the phosphate fertilizer, in one of sugarcane main cultivated areas named Western Yue in Guangdong province, two types of fertilizer speciality for sugarcane were made according to the investigation of soil nutrients in the field. They contain mainly the filtrated mud, the ethylalcohol waste liquid and other by-products from sugar industrial process.In this experiment, sugarcane varieties of YueTang 95-168,FuNong15 and YueTang93-159 were taken as the plant materials. The split-plot design was adopted and a set of four applied fertilizer treatments, treatment T₀ (one of compared experiments), treatment T₁ (another compared experiments based on the traditional fertilizer applicational protocol of local sugarcane peasants), treatment T₂ (special fertilizer for sugarcane, including base manure type and topdressing type), treatment T₃ (biological organic-fertilizer and special topdressing type fertilizer), was accupied. The results of fertilizers affect on sugarcane growth and main soil nutrient contents were investigated. The main results were as follows.First, T₂ and T₀ could significantly increase the germination rates of sugarcane compared to T₁．T₂ could obviously promote the main stalk growth of sugarcane. From the stage of initial elongation growth to the last investigation in early October, T₂ was obviously better than treatment T₁ all the time, and the significant difference between T₂ and T₁ was also observed from the end of July. At the same time, the similar tendency and results were also observed in the main stalk growth speed per month between T₂ and T₁．For the photosynthesis, the average of net photosynthetic rate and transpiration rate of sugarcane leaf in T₂ were in top position and was significant higher than T₁．These results indicated that sugarcane special fertilizer was favorable to sugarcane's growth.Second, No stable effects on characters of cane fiber content and gravity purity of cane juice were found in different treatments and the differences among treatments weren't significant. The synthesis effect on sucrose content for all test varieties in T₂ was significant higher than other treatments. It indicated that the sugarcane special fertilizer could remarkably enhance the sucrose accumulation compared to the traditional one for local sugarcane peasants.Third, No significant differences between different treatments were found in sugarcane yield characters of plant height, stem diameter, weight of single stalk and stalk yield. Relative strong effect on the number of millable stalk, but the trend wasn't stable. They had relative significantly effective differences in sucrose yield, except the YueTang93-159 had no significant differences among the four fertilizer treatments, the treatment T₀ of YueTang 95-168 had significantly higher level than treatment T₁ and T₃, and it was equal to the treatment T₂, at the same time the treatment T₂ had also significantly higher level than treatment T₁; the treatments T₂ and T₃ of FuNong15 had significantly higher levels than treatment T₁, because the four fertilizer treatments had great effects on the sucrose yield. Compared with the traditional fertilizer applicational protocol of local peasants, these results indicated that the special fertilizer for sugarcane could remarkably increase the sucrose yield through inc reasing the sucrose content in cane.Fourth, Analysis of the effects of fertilizer on the soil nutrient content in cane-field, we observed that T₂ was best treatment for cultivation of soil fertility. The performance showed it significantly improved the soil fertility compared to other treatments, which could enhance the content of soil organic matter, total nitrogen, total phosphorus, total potassium, basic soluble nitrogen, rapidly available phosphorus, exchangeable calcium, exchangeable magnesium, water-solubility boron, effective zinc et al. The effects of fertilizer treatments on the contents of rapidly available potassium and effective molybdenum were uncertainty. No obvious improvement of soil acid value was found in all treatments.The results will provide the scientific basis for the additional application of sugarcane special fertilizer in sugarcane field in Suixi, Guangdong Province. They were instructive for usage of sugarcane fertilizers, and it also could promote the by-products utilization and environment protection, so it accorded with the production pattern of cycle economy.