Abstract
A population of eight open pollinated families of Pinus contorta was selected from sites varying in precipitation regimes and elevation to examine the possible role of aquaporins in adaptation to different moisture conditions. Five Pinus contorta aquaporins encoding PiconPIP2;1, PiconPIP2;2, PiconPIP2;3, PiconPIP1;2, and PiconTIP1;1 were cloned and detailed structural analyses were conducted to provide essential information that can explain their biological and molecular function. All five PiconAQPs contained hydrophilic aromatic/arginine selective filters to facilitate the transport of water. Transcript abundance patterns of PiconAQPs varied significantly across the P. contorta families under varying soil moisture conditions. The transcript abundance of five PiconPIPs remained unchanged under control and water-stress conditions in two families that originated from the sites with lower precipitation levels. These two families also displayed a different adaptive strategy of photosynthesis to cope with drought stress, which was manifested by reduced sensitivity in photosynthesis (maintaining the same rate) while exhibiting a reduction in stomatal conductance. In general, root:shoot ratios were not affected by drought stress, but some variation was observed between families. The results showed variability in drought coping mechanisms, including the expression of aquaporin genes and plant biomass allocation among eight families of Pinus contorta.
Highlights
Trees cope with different environmental stresses through diverse physiological and molecular responses
We focused on four plasma membrane intrinsic proteins (PIP1;2, PIP2;1, PIP2;2, and PIP2;3) and one tonoplast intrinsic protein (TIP1;1) in order to better understand the role of these genes in Pinus contorta under drought stress
Eight families of P. contorta were selected from locations with different climactic conditions based on the summer heat:moisture index
Summary
Trees cope with different environmental stresses through diverse physiological and molecular responses. Drought is one of the main abiotic stress factors limiting forest productivity and enhancing insect pests and pathogen-related diseases, increasing forest susceptibility to wildfires and, resulting in extensive tree mortality [1,2,3,4,5,6,7,8]. Trees cope with drought stress either through drought avoidance mechanisms that maintain tree water status by preventing water loss or increasing water delivery to leaves, or through tolerance mechanisms which help trees to function under low tissue water potentials when drought levels become too severe [9,10]. Stomatal closure prevents water loss, and reduces CO2 assimilation and negatively affects photosynthesis, affecting tree growth [11,12,13]. On the other hand, could lead to tree death if stomata remain open for too long.
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
