Study On Growth And Photosynthetic Characteristics Of Tea Plants In Photovoltaic Tea Field

Photovoltaic(PV)agriculture is a kind of agricultural energy composite production system that simultaneously performs PV power generation and agricultural production on the same land.PV agricultural facilities have opened a new development mode of modern ecological agriculture while efficiently using solar energy resources and producing clean green energy.However,the laying of PV panels has also changed the growth environment of crops,affecting the growth of crops grown under PV agricultural systems.In most cases,the shading of crops leads to a decline in agricultural economic performance.Tea plant(Camellia sinensis L.)is a shade-tolerant crop,and shading is a common agricultural measure in tea production.The PV tea plantation is not only helpful for sustainable development,through PV power generation,the output value of the tea plantation can be effectively increased.In the experimental research,a checkerboard fixed PV system tea plantation and a horizontal single-axis tracker PV system tea plantation were established.The PV tea plantation has the same variety as the control open-air tea plantation,and it is a 15-year-old strip planting tea cultivars 'Jiukeng' in the tea plantation.1.In terms of the microclimate of the tea plantation:(1)The the solar radiation of both two PV tea plantation received by the canopy of the photovoltaic panels.The shading of the PV panels on the underlying tea plants changes over time throughout the day.(2)During the germination period of tea plant,the PV system can increase the lowest temperature at night and effectively prevent the cold spell in later spring.In high-temperature season,the system effectively reduces the peak temperature during the day.(3)The PV system can maintain the humidity of the tea canopy.2.In terms of tea tree germination and tea production:(1)The tea trees in the two types of PV tea plantation have earlier spring germination periods and longer harvest periods.(2)The output of tea before the Pure Brightness,the tea yield in spring,summer and autumn PV tea plantations all increased,and the growth of tea in the PV tea plantation is uniform.3.In terms of tea quality:(1)The 100-bud weight of tea trees in PV tea plantations are significantly higher than that in the open-air tea garden,and the tea buds are stronger.The growth of tea and the quality of the new shoots in the PV tea plantation is uniform.(2)The amino acid content of tea in both two PV tea plantation are higher than that in open-air tea plantation.However,the catechins content of the a horizontal single-axis tracker PV system tea plantation was generally lower than that of the open-air control,while the checkerboard fixed PV system tea plantation was slightly higher than the open-air control.(3)Tea sensory evaluation data of the Maofeng green tea made by photovoltaic tea showed that the total score of tea in PV tea plantation is higher than that of open-air tea plantation.4.In terms of the morphology and colort of ea leaf:(1)The leaf areas and the length and width of tea leaves of the third and fourth leaves of tea trees in PV tea plantation are significantly larger than those in open-air tea plantation.(2)The tea leaves in PV tea plantation is obviously greener.The leaves in PV tea plantation have higher pigment contents,especially chlorophyll,in the tea trees than that in the openair tea plantations.The ratio of chlorophyll a/b in spring tea leaves of PV tea plantation was significantly lower than that of open-air tea plantation.5.In terms of photosynthetic characteristics of tea trees:(1)tea trees in PV tea plantation have lower light compensation points and light saturation points,have higher light quantum efficiency under weak light.(2)Moderate shading of PV panels can mitigate the photoinhibition by preventing the strong light in summer,which is beneficial to the synthesis and accumulation of chlorophyll in tea leaves and enhances the photosynthetic capacity of tea.(3)The relative quantity of gene expression of PsbC,a related gene of photosystem ?,was significantly increased in tea leaves in the shaded and light-receiving areas of photovoltaic tea gardens,which were 260 times and 40 times that of open-air tea plantation,respectively,suggesting an increase for tea leaf in the utilization of light.