Studies On Development Of The Tobacco Special Slow-Released Fertilizer And Its Functionary Mecanism

Tobacco is an important economic crop in China and fertilization is one of the key technologies of tobacco cultivation system. In the present main cultivation system, fertilization is not only the 1^st determined factor of the yield and quality, but also the factor with higher effects on the average price and ratio of the first class of flue-cured tobacoo leaves. Fertilizer contributes only less than variety to tobacco flavor. As a result, fertilization is one of the key technologies regulated the yield and quality of tobacco in certain in ecology and variety circumstances.According to the fertilizer requirement trait of tobacco, namely, the plants, with early development and quick growth at early stage, require not only the rapid release but also the long-lasting release of fertilizer to supply the cultivation of strong roots system (growth promotion), B fertilizer particle microcapsules were made with higher content of N and P but median content of K. At the mean time, D fertilizer particle microcapsules were made with higher content of K but median content of N to meet the demands of tobacco plant at middle and later stage and promote maturity. These two kinds of particles were mixed in a certain proportion to made the tobacco special slow-released fertilizer (higher efficient BD fertilizer), and the effects of the BD fertilizer on the growth and development as well as economic characteristics of flue-cured tobacoo were studied in the paper. It was found that the nutrients were released by phases to realize the balanced supply of nutrient during the whole growth period, and achieve the goal of increasing the quality and output with less environmental pollution and less amount of fertilization but higher fertilizer efficiency in tobacco production industry.1. Preliminary investigation indicates that rice synergist could improve the early growth and development and tillering ability of rice plants, and promote dry matter accumulation by improving the photosynthetic performance and root absorptive capacity at the same time. Here, synergist of flue-cured tobacco was found to promote root development, significantly improve the volume and fresh weight of root system, especially maintain the vigorous root at mature stage to guarantee the nutrient absorption of tobacco plants.2. Synergist could increase the content of GA3 and IAA, and decrease the content of ABA within the root, thus benefit the growth and development as well as the formation of high quality of tobacco leaves. Synergist could also enhance the content of spermine and spermidine, reduce the content of putrescine within the root, depress the synthesis of nicotin to a certain extent and improve the resistance to stresses, and thereby improve the quality of tobacco.3. It was showed that spray-drying method, squeeze-into-capsule method, oil-phase-separation method and mix-into-capsule method could meet the demand of D particles design, among them mix-into-capsule method had the optimal processess, the lowest costs and the better encapsuled effects.4. BD fertilizer appliction could heighten physiological activity of tobacco. Compared with the equal level of conventional fertilization, the plants with BD fertilization had increased chlorophyll content with little variation from flourishing stage to tip pruning stage and delayed senescene process at muture stage. And the later the growth stage, the more obvious of the increment of tobacco photosynthetic capacity by the slow-release fertilizer.5. BD fertilization had little effects on alkaloids, neutral and acidic aroma materials of the flu-cured tobacco.6. Under the same fertilization level, field tobacco plants with BD fertilizer grew evenly and gently with good-looking leaves and healthy configuration, light leaf color without early senescence and fine maturation characteristic. The flue-cured trait was also improved obviously and the yield and output, the ratio of high and middle class of leaves and the average price was higher than that of the control.7. According to results of the field demonstration project of Daili, 4.8 kg/mu was found to be the best application dosage of BD fertilizer for Hong hua da jin yuan under middle and high class of field fertility. The economic traits of plants such as yield per mu, yield value per mu, ration of the 1^st class of leaves, ration of the 1^st and middle class of leaves and average price were better than that of the control.8. According to results of the field demonstration project of Huayuan, BD fertilization could improve the quality of tobacco leaves in a certain extent and affect significantly the economic output of the flue-cured tobacco especially. Under the equal fertilization level, the economic output was 16.41% higher than that of the control in field plot trial, and 14.58% higher than that of the control in field demonstration project. The the economic output of the flue-cured tobacco, with the reduced aplication dosage by 11.11%, was 14.17% higher than that of the control, and the sensory evaluation was also improved to some extent.