Abstract:

To choose the most suitable method for light and temperature management of young ‘Huangjinya’ in Bikou tea area of Wen County of Gansu Province, two-year-old ‘Huangjinya’ tea seedlings were used as experimental materials to study three different light and temperature management methods such as single shed film (T1), single shade net (T2), shed film+ shade net (T3) on the growth of summer shoots and chlorophyll fluorescence parameters of ‘Huangjinya’ leaves, no shed film without shade net (CK) as a control. The results showed that shading could increase the initial fluorescence (F₀) of ‘Huangjinya’ leaves, significantly increase the maximum fluorescence (Fm) of the ‘Huangjinya’ leaves, and the photochemical quantum efficiency (Fv/Fm) of ‘Huangjinya’ leaves at 13:00 and 15:00. T3 significantly increased the excitation energy capture efficiency (Fv'/Fm') of the open-cell PSⅡ reaction center of the ‘Huangjinya’ leaves at 13:00 and 15:00; shading significantly reduced the photochemical quenching coefficient (qP) of the ‘Huangjinya’ leaves at 11:00, 13:00 and 15:00. The non-photochemical quenching coefficient (qN) of T2 was significantly lower than that of CK at 15:00; and T1 and CK caused light suppression at 13:00 and 15:00 for the ‘Huangjinya’, however, it did not cause damage to the PSII reaction center. Shading of ‘Huangjinya’ in Bikou town of Wen County of Gansu Province could increase the Fv/Fm and reduce the qP. Full light could cause inactivation of the PSII reaction center and photo inhibition at 13:00 and 15:00. Therefore, in the light and temperature management in ‘Huangjinya’ cultivation, moderate shading should be carried out in the dog days.

Key words: ‘Huangjinya’, light and temperature management, chlorophyll fluorescence parameters, tea tree, Longnan in Gansu Province, shading