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Strawberry is the most important one of the berries, production and cultivation area in the berries after the grape 2003 of strawberries area has reached 82,000 hectares, production of 1.338 million tons, ranking first in the world. Zhejiang is the main origin of strawberry, Zhejiang strawberry cultivation area of ??over 06,000 ha in 2003, yield more than 120,000 tons. With China's accession to WTO, the strawberries will face fierce competition in the international market, high-quality strawberry production is imminent. The artificial light, CO the 2 fertilization and reasonable for nitrogen strawberries protected cultivation has become an important technical measures. Strawberry production, there are still the following questions: (1) light suppression: summering plants the strawberry shade-tolerant crops, open field cultivation vulnerable to photoinhibition and photooxidation damage leaves in bright light, often leads to death; (2) for the level of nitrogen regulation: high nitrogen conditions could easily cause a leggy plants, the rate of fruit drop and fruit quality. Low nitrogen affects plant growth, leaf yellowing, thereby affecting photosynthesis, resulting in resistance weakening and decline in yield and quality; (3) CO 2 Supply: strawberry cultivation in China is often in the facility environment, in a closed strong the facility air circulation inside the facility CO , 2 Supply lack of affect photosynthesis, thereby affecting the yield and quality, often leading to; (4) light and light quality problem: cultivation, the light passes through the Glass and plastic films, light intensity and light quality facilities are changed, these changes, especially changes in light quality, there is no clear understanding of the impact on the growth and results. The above problems predecessors had local, but in the lack of in-depth study on the mechanism, for this study of strawberry as test materials, features and glare protection mechanism to be adopted by the strawberry leaves photosynthesis photoinhibition, nitrogen levels 2 response mechanism, the CO 2 add rich and nitrogen levels interaction the strawberry leaves light protective system of D1 protein turnover in strawberry leaves, strawberry leaves photosynthesis Fu CO , photoprotection mechanism of action, light quality of strawberry leaves photosynthesis and chlorophyll fluorescence, and light quality on six strawberry growth and development and fruit quality of the mechanism of research, in order to provide a theoretical basis to solve common problems in strawberry production The main results are as follows: 1) strawberry leaves under the bright fluorescence parameters and apparent quantum efficiency changes with a portable modulated chlorophyll fluorescence analyzer and photosynthesis system. The results show that, Fm, Fv / Fm, the number of PS II reactive center and Q A reduction rate is reduced under a bright light, increased recovery in the dark; PS Ⅱ reaction center non-reducing the proportion of the Q B increase in bright light, reduce recovery in the dark. Variation of the fluorescence parameters are light stress or dark recovery 10 min before. Under strong light the phi PSII , ETR and qP first increased and then reduced, but qN significant reduction in first, and then rebounded slightly. Light for 4 h, the abundance of incense and Hokowase apparent quantum yield (AQY) were reduced by 20.9% and 37.5%; qE (energy-dependent non-photochemical quenching) for most of the NPQ (non-photochemical quenching) the main ingredient. The light stress the Toyonoka fo, FM, Fv / Fm, phi PSII the ETR and AQY the variation than cross the Po Early. DTT treatment, the strawberry leaves Fm and Fv / Fm significantly reduce Fo significantly increased. These results suggest, dependent xanthophyll cycle and thylakoid membrane proton gradient of two non-radiative energy dissipation in the strawberry
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