Leaf gas exchange differences between males and females of yerba-mate
Keywords:
Light, photosynthesis, stomatal conductance, temperature, transpirationAbstract
A preliminary study was developed on leaf gas exchange properties of males and females in yerbamate (Ilex paraguariensis St. Hil.), planted in open growth conditions. The photosynthesic photon flux density (PPFD) on leaf level, stomatal conductance (gs), net photosynthesis (A), transpiration (E), and leaf temperature (Tl) was measured during the biennial production period: in the summer during the fruit ripening when there is a pause in its growth (January, February), spring sprouting (November) and autumn sprouting (March, Jun). The measurements have been taken in different tree crown positions (inside, exterior and tips). First indications of sex physiological dimorphism in yerba-mate have been shown. Conductance was superior on female plants, with exception on tips, whereas the A and E were superior on females, on the exterior of the third medium of the tree crown. Positive correlations among gas exchange properties and PPFD were established. The seasonality in gas exchange was observed. The maximum gas exchange values were registered in active sprouting whereas the minimum values were registered during fruit ripening, in full summer. A and E were positively correlated with gs for both males and females. The functional strategy of females, aiming to finish the reproductive process, is to proportionate the relative increase of A and E on self-shaded leaves, through the superior gs compared to males.Downloads
Downloads
Published
How to Cite
Issue
Section
License
The BRAZILIAN JOURNAL OF FORESTRY RESEARCH reserves the right to correct grammar, improve clarity, and impose PFB standard although respecting the author's style.
Final proof version will be sent to the correspondence author.
Published papers will become property of the BRAZILIAN JOURNAL OF FORESTRY RESEARCH.
Published papers may be used by the authors, without previous PFB authorization, allowed when source is cited.
Any mention of trademarks or methods do not imply in its recommended by the Editorial Committee.
The authors are the exclusive responsible for opinions and concepts developed in the manuscript.