Temperature responses of photosynthesis and leaf hydraulic conductance in rice and wheat. (3rd March 2020)

• Record Type: Journal Article
• Authors: Yang, Yuhan; Zhang, Qiangqiang; Huang, Guanjun; Peng, Shaobing; Li, Yong
• Is Part Of: Plant, cell and environment. Volume 43:Number 6(2020)
• Page Start: 1437
• Page End: 1451
• Publication Date: 2020-03-03
• Subjects: leaf hydraulic conductance -- leaf water potential -- mesophyll conductance -- photosynthetic limitations -- temperature; Plant physiology -- Periodicals; Plant cells and tissues -- Periodicals; Plant communities -- Periodicals; 581.105
• DOI: 10.1111/pce.13743
• Languages: English
• ISSNs: 0140-7791

Abstract

Abstract: Studies on the temperature ( T ) responses of photosynthesis and leaf hydraulic conductance ( K leaf ) are important to plant gas exchange. In this study, the temperature responses of photosynthesis and K leaf were studied in Shanyou 63 ( Oryza sativa ) and Yannong 19 ( Triticum aestivum ). Leaf water potential (Ψleaf ) was insensitive to T in Shanyou 63, while it significantly decreased with T in Yannong 19. The differential Ψleaf − T relationship partially accounted for the differing g m – T relationships, where g m was less sensitive to T in Yannong 19 than in Shanyou 63. With different g m – T and Ψleaf – T relationships, the temperature responses of photosynthetic limitations were surprisingly similar between the two lines, and the photosynthetic rate was highly correlated with g m . With the increasing T, K leaf increased in Shanyou 63 while it decreased in Yannong 19. The different K leaf – T relationships were related to different Ψleaf – T relationships. When excluding the effects of water viscosity and Ψleaf, K leaf was insensitive to T in both lines. g m and K leaf were generally not coordinated across different temperatures. This study highlights the importance of Ψleaf on leaf carbon and water exchanges, and the mechanisms for the g m – T and K leaf – T relationships were discussed. Abstract : Studies on the temperature ( T ) responses of photosynthesis and leaf hydraulic conductance ( K leaf ) are important to plant carbon gain and water loss. Our data showed that the temperature response of leaf water potential (Ψleaf ) was different between Shanyou 63 ( Oryza sativa ) and Yannong 19 ( Triticum aestivum ), which, at least partially, accounted for different temperature responses of K leaf and mesophyll conductance ( g m ) between the tested lines. The mechanisms underlying the temperature responses of K leaf and g m were discussed.