Studies On Photosynthetic Traits And Chloroplast Ultrastructure Of 6 Tea Characteristic Varieties(Lines)

Photosynthesis is the decisive factor of productivity. In the cultivation and breeding of tea plant, the photosynthetic physiological characteristics can be used as an important index to evaluate its adaptability and productivity.Taking the new char-acteristic tea varieties (lines) Jin Guang,Huang Jinya,An Jibaicha,Simingxueya,Zi Yan and Zi Juan as tested materials. Taking Fu Dingdabaicha as contrast.In order to reveal basic photosynthetic physiological characteristics of the 6 varieties (lines), improve the photosynthetic efficiency and provide some reference to formulate corresponding with high yield and good quality cultivation and management techniques, the photo-synthetic traits,the chloroplast ultrastructure and chloroplast ultrastructure of tea leaves are reserched.Research results showed that:(1) There were significant differences in the photosynthetic efficiency and chloro-plast ultrastructure of the tested varieties (lines) leaves. Compared with the control of Fu Dingdabaicha. Zi Yan and Zi Juan belong to the varieties(lines) with high photo-synthetic efficiency and Huang Jinya and An Jibaicha belong to the varieties with low photosynthetic efficiency.(2) The order of net photosynthesis rate of tested varieties (lines) leaves in spring from high to low is Zi Yan> Zi Juan>Jin Guang>Si Mingxueya>An Jibaicha> Huang Jinya.The transpiration rate of Zi Yan reached 4.20mmolH2O/m2·s,but An Jibaicha only 1.55mmolH20/m2·s.The order of net photosynthesis rate in summer from high to low is Zi Yan> Zi Juan> Si Mingxueya>Jin Guang>An Jibaicha> Huang Jinya,and the transpiration rate of different varieties (lines) were significantly lower than that of the control.The order of net photosynthesis rate in autumn from high to low is Zi Juan>Jin Guang> Huang Jinya>Zi Yan> Si Mingxueya>An Jibaicha,and the transpiration rate of tested varieties (lines) were all significantly higher than Fu Dingdabai.(3) The net photosynthetic rate,stomatal conductance and photosynthetic pigment contents of different leaf positions(one bud and six leaves)of the tested varieties (lines) were increased with the increase in number of shoot leaf which means leaf age in- creased,intercellular CO2 concentration decreased with the increase in number of shoot leaf decreased.(4) By the light response curve fitting parameters of light,in spring, the light adapta-tion abilityof Jin Guang and Huang Jinya were the weakest, and the low light utiliza-tion efficiency of Zi Yan, Zi Juan and Jin Guang were relatively high.In summer,the low light utilization efficiency of Zi Yan and Si Mingxueya were high.In autumn, the light adaptability of Zi Juan was equal to the control,but the other 5 tea varieties (lines) were weaker than the control.Si Mingxueya and Zi Yan had high weak light use effi-ciency. The light saturation points of all varieties (lines) were all summer> autumn> spring.(5) In spring and autumn,the curves of the daily variation of the net photosynthetic rate of the 6 tested tea varieties (lines) were all single peak shape.In summer.the curves of the daily variation of the net photosynthetic rate of An Jibaicha,Si Mingxueya,Zi Yan and Zi Juan were single peak shape.While the curves of the daily variation of the net photosynthetic rate of Huang Jinya, Jin Guang and the control were two peaks shape.There was the phenomenon of "midday depression".Correlation analysis showed that, in spring and autumn, net photosynthetic synthetic rate and light illumination intensity of the tested varieties (lines) had significant positive correla-tion.And net photosynthetic rate and relative humidity had significant significant pos-itive correlation in summer.(6) There were differences among the photosynthetic pigment content of the tested varieties (lines) in different seasons.In spring,the total chlorophyll content of all varie-ties (lines) was significantly lower than that of the control.In summer, photosynthetic pigment content of Zi Yan and Zi Juan were higher than the control while the other tea varieties (lines) were lower than the control.The content of total chlorophyll and arotenoid pigment of Huang Jinya were the lowest,respectively 0.52mg/g and 0.22mg/g.In autumn,the highest content of total chlorophyll and arotenoid pigment were respectively Zi Yan and Zi Juan,3.84mg/g,0.22mg/g.The contents of photosyn-thetic pigment in purple tea varieties were higher than those in white varieties lines, followed by yellow varieties lines.The chlorophyll content of tested varieties (lins) was summer> autumn> spring.(7) The chloroplast numbers in mesophyll cells of 6 tested tea varieties(lines) were lower than the control.The volume of chloroplast of Zi Yan and Zi Juan which have large number of chloroplast are both large, respectively 1.78×1.11?um,2.36×1.17 ?m. The number and volume of chloroplast of Huang Jinya are small. The number of gra-na layer in chloroplast of An Jibaicha was most,which was 45.67.The order of the number of grana layer in chloroplast was Zi Juan>Zi Yan> An Jibaicha>Fu Ding-dabaicha>Jin Guang>Si Mingxueya>Huang Jinya.Zi Juan has 32.58±4.88 and Huang Jinya has 2.13±0.28.The correlation analysis showed, there was extremely sig-nificant positive correlation between the net photosynthetic and the chloroplast num-ber inside cell of the tea leaves with the correlation coefficient.In summary, Zi Yan and Zi Juan belong to the varieties (lines) with high photo-synthetic efficiency and Huang Jinya and An Jibaicha belong to the varieties with low photosynthetic efficiency.But the photosynthetic efficiency of 6 tested varieties(lines) were weaker than control.Therefore, in order to improve the light efficiency.planting above characteristic varieties(lines), should pay attention to adjust the light, strength-en water and fertilizer supply.