Studies On Biologic And Physiologic Characteristics Of High-yield Castanea Mollissima BL

High yield of Castanea mollissima BL is the result responded to biologic, physiologic, ecologic and genetic characteristics of the high-quality breed, and biologic and physiologic characteristics are the effect of ecologic and genetic working together. It is very significant in theory and practice for understanding the mechanism of high yield to study on biologic and physiologic characteristics of Chinese chestnut.There are some relationships between biologic characteristics and yield and between different characteristics. But which characteristic is the most important factor yield is affected? Based on the measures of main biologic characteristics such as body structures, phenological term, flowering, the paper finds the most significant factor to affect yield by statistical analysis. The results show that: fruit-branch, shape of tree and crown canopy are the there main factors in body structure, and yield is obviously related to fruit-branch; sum of female-flower and flowering in . different term for female and male flowers have a big influence. Meanwhile, phenological term and flowering term all are very obviously related with the yield; sum of female-flower, flowering in different term for female and male flowers and fruit branch become the most main there factors to affect the yield.Physiologic characteristics are the responses of living law and mechanism of plant in a variety of environmental conditions. The paper explores the mechanism of high yield and finds the main physiologic factors to affect the yield through studying the characteristics of photosynthetic characteristics, contents of chlorophyll, mineral elements, plant hormone, water metabolism, fluorescence dynamics, nitrate reduction enzyme and hardiness physiology in 10 breeds of Chinese chestnut. The research results show that: there is a difference and similar law in which are related with the factors of stomata, water transpiration and contents of CO2 for different breeds in diurnal and seasonal changes. Meanwhile there is a significant relation both between photosynthetic characteristics and output and between photosynthetic characteristics; parameters of fluorescence reflect the transformation and utilization ratio of light energy, electron transport, light chemical reaction and potential activity of photo-system and have a large difference in different breeds. Fv/Fm and ETR are the main factors in photo-system to affect yield and are related to photosynthetic characteristics; Under stress the changes of Fv/Fm reflect the abilities of hardiness in different breeds which is positively related to photosynthetic rate and nitrate reduction enzyme; the changes of content of mineral element have not the regularity, but when taking the N, P and K as a integration and a compound element, the changes of compound element exist some laws and are related with yield and sum of female flower; The C/N adjusts and controls flowering and is related with sum of female-flower and yield in different breeds. Photosynthetic rate and contents of chlorophyll affect flowering and fertilization; There are a significant difference in seasonal changes and there are a similar law of change in nitrate reduction enzyme for different breeds. The activationof nitrate reduction enzyme increasingly grows from May to August, but it begins declining after August because nitrate reduction enzyme is a kind of reduced enzyme which is induced and stimulated by high temperature and demand of N; Nitrate reduction enzyme accelerates the metabolism of N, quickens photosynthetic rate, increases the C/N and finally promotes flowering, and it is related markedly with yield but has little affection to Fv/Fm.. So that show Fv/Fm is controlled by genetic factors. Activation of nitrate reduction enzyme is positively related with C/N and N*P*K but negative related with contents of N. It may be that N restrains the induce of nitrate reduction enzyme; There is a significant distinction in contents of the plant hormone for different breeds but excerpt GA3 all other plant hormones have not a definite law. Using out-hormone can induce several high-yield breeds to produce indefinite roots and indefinite buds. What the most breeds cannot been induced maybe is because of shorting the hormone receptors or receptors restrained by something; GA3 and ZR are markedly related with the yield and sum of female-flower but the experimental results of other plant hormones is not accorded with their actual works. The experiment of induce producing indefinite roots or buds proves that the reason may be related to hormone receptors, of cause it also may be related to experimental data errors.According to principal component analysis, physiologic factors are divided three principal components related with yield, that is photosynthetic factor, nutritious element factor and fluorescence factor. The main physiologic factors that have the most affection to yield are transpiration rate, photosynthetic rate, C/N and Fv/Fm by canonical correlation analysis in biologic and physiologic factors.The mechanism of high-yield Chinese chestnut is recognized elementally based on biologic and physiologic characteristics. Physiology is a wide scientific domain. To enhance the level of research and understand the mechanism of high-yield Chinese chestnut, studies on physiologic characteristics are supplemented and improved in respiration metabolism and hardiness physiology, and researches of molecular biology on genetic adjustment and cell signal transduction should been looked forward to understanding the mechanism of high-yield of Chinese chestnut.