Heterosis effects on photosynthesis of upland cotton (Gossypium hirsutum) hybrid cultivars

Abstract

The relationship between the environment and heterosis effects on the photosynthesis of upland cotton (Gossypium hirsutum) is unknown. No significant differences for net photosynthetic rate (PN), stomatal conductance (gs), and transpiration rate (E) were found between two studied cotton varieties Siza 3 and Zhongmiansuo 48. The PN and gs of Siza 3 demonstrated heterosis compared with its parents. The higher the effective photosynthetic radiation and CO2 concentration were, the more obvious the over better-parent heterosis (OH) of the PN was. The photosynthesis parameters of Zhongmiansuo 48 in different environments did not display obvious OH, but the PN of Siza 3 was higher than that of Zhongmiansuo 48. The performance index of the absorption (PIabs) of Siza 3 was higher than that of Zhongmiansuo 48. The PIabs was significantly related to the OH of the PN. The OH of the PN of hybrid cotton can be predicted via the PIabs under high temperature and light.

Keywords

• environmental factor
• fluorescence
• light intensity
• photosystem ii