| Exploration and use of natural material is one of important issue of resource and environmental chemistry study. As a reproducible resource with excellent applied property, Chitin widely consist in arthropod, mollusk, insect, animalcule and plant. It is second natural macromolecule polymer inferior to cellulose quantitatively. As estimate, On the whole world, Quantity of chitin synthesized by biologic organism hit about billions tons. At present, Application and research of amylose resource is very active. Especially, research of chitin is still underway.China not only is a country possess of abundant aquatic product resource but also is a the most large country breeding silkworm. Consequently, in china resource of chitin is abundant. Chinese expert began the research job about chitin in early period. However, the level of study is lower than occidental country. Especially, in recent years. Actual problems of research job about chitin have two hands. Firstly, the study on method of production of chitosan is short of creativity. Secondly, the study on expansion of application of chitosan is not enough, especially, Agricultural application. In this paper, aimed at the problems of previous studies, carried out study of production of chitosan and its application in agriculture through experiment.Collecting of Experiment material start in 2003, Select shell of native field snail as raw material of production of chitosan. Soil sample chosen acidic purple soil and alkalescent purple soil. This experiment was carried out base on two parts. One parts is experiment of production of chitosan, experiment would testify feasibility of raw material and effect of method designed by ourselves. In order to optimizing control conditions in step of removing acetyl, cross experiment was designed. The other part is experiment of effect of chitosan treatment on horsebean nitrogen fixation system planted in different purple soil. Moreover, mechanism of effect will be discussed simply. In order to request the effective factor of horsebean nitrogen fixation system, two-factor, two-level was designed. Experiment included treatment with chitosan solution of two concentration levels (400times, 200times) and soil of two properties.New method of production of chitosan is use NaClO as a substitute of previous decolor reagent, in step of removing acetyl, multiphase impregnant environment with ethanol and sodium hydroxide solution was designed, disperse dripping way was used in process, moreover, reduced intensity of condition of reaction.As result of experiment show right product can be got by new method. concentration of sodium hydroxide solution in process of production fall by 15% from 45% to 30%. Degree of deacetyl increase by 21% from 70% to 91%. molecular weight increase from 5.09×10~5 to5.56×10~5.optimization control conditions of removing acetyl step chosen by cross experiment are concentration of sodium hydroxide solution: 30%-~35%(w%), temperature of reaction: 80°C~90°C, time of reaction:10 hours.The study of effect of chitosan treatment on horsebean commensal nitrogen-fixation system adopt a way of potted plant experiment combine with assaying to investigating. After soil sample was air-dried, some soil properties such as pH level, effective nitrogen, effective phosphor , active iron, effective boron, effective molybdenum, etc would be mensurated. Vicia fabas that put in acid purple soil and alkaline purple soil were irrigated with 200 times solution of chitosan and 400 times solution of chitosan. The plants was irrigated a time average a week with 100ml solution of chitosan per time and Continue the operation four weeks.Five results were showed after experiments have finished. First, amout of vicia faba root nodule which were irrigated is more than CK obviously. Second, Effect of treatment in alkaline purple soil is better than that in acid purple soil. Third, Effect of high concentration is better than low concentration. Forth, Change law of nitrogenase activity is same with change law of amout of root nodule. Furthermore, change of plant growth is small. Fifth, population of vicia faba rhizobium which were irrigated is more than CK obviously, Effect of high concentration is better than low concentration, Effect of treatment in alkaline purple soil is better than that in acid purple soil.Result of Statistical analysis shows effect of unique soil factor, effect of unique chitosan factor and mutual effect of two-factor on amout of vicia faba root nodule is notable(n=5, a=0.05). effect of unique chitosan factor and mutual effect of two-factor on nitrogenase activity is not notable(n=5, a=0.05), only effect of unique soil factor on nitrogenase activity is notable(n=5, a=0.05). effect of unique soil factor and effect of unique chitosan factor on amout of vicia faba rhizobium is notable(n=5, a=0.05), mutual effect of two-factor on amout of vicia faba rhizobium is not notable(n=5, a=0.05). in alkaline purple soil, effect of unique chitosan factor on amout of vicia faba root and nitrogenase activity is notable, effect of unique soil factor on amout of vicia faba root nodule and nitrogenase activity only in high level chitosan solution is notable. However, in acidic purple soil, effect of unique chitosan factor on amout of vicia faba root nodule and nitrogenase activity is not notable, effect of unique soil factor on amout of vicia faba root nodule and nitrogenase activity in low level chitosan solution is not notable. Above consequence shows in alkaline purple soil, effect of unique chitosan factor on amout of vicia faba root nodule and nitrogenase activity is more bigger, effect of unique soil factor on amout of vicia faba root nodule and nitrogenase activity in high level chitosan solution is bigger. Effect of two factor on each level on amout of vicia faba rhizobium is same. Result of Statistical analysis also shows effect of two factor on growth of vicia faba plant is notable.configuration of molecule of amylose is similar to chitosan. Their difference in that dissociative amidocyanogen in configuration of molecule of chitosan. So amylose can be used as a substitute of chitosan for studying mechanism of effect of chitosan on vicia faba commensal nitrogen-fixation system.Consequence of Experiment shows effect of amylose on vicia faba commensal nitrogen-fixation system is small. As a result, we can assume that function of dissociative amidocyanogen in configuration of molecule of chitosan is big in the whole process.Due to limit of time, we can not carry out more experiments about other leguminous plants. So we hope that the research job can keep on doing, even now, result of our experiment has approve validity of chitosan to commensal nitrogen-fixation system.
|
PDF Full Text Request