Comparative examinations of gas exchange and biometric parameters of eight fast-growing poplar clones
The establishment of short-rotation poplar plantations for the sustainable production of raw material and energy is often limited by low precipitation and poor soil conditions. Breeding research must therefore focus on combining performance with drought tolerance. Eight poplar clones were generated by tissue culture. Three times during seasonal development, photosynthesis and transpiration were measured in fully developed leaves under controlled conditions in a climate chamber. Light response curves were modelled based on these data. The efficiency of water use was analysed for all clones under well-watered conditions, and partly significant differences were observed with regard to intrinsic water use efficiency (WUE). Moreover, at the end of the season, the plants were considerably different in their biometrics, particularly in the shoot–root relationship, which might substantially influence drought resistance. A general ranking of the performance of the clones is difficult because certain physiological parameters turn over during the course of the season. However, certain “strategies” that could be divided into “generalist” and “specialist” stand out for individual clones. The aspen clone Großdubrau 1 (“specialist”) showed the maximum height, the greatest seasonal differences in WUE and the most weakly developed root system. By contrast, the poplar clone Max 2 (“generalist”) had the lowest height increase but a well-developed root system and lower volatility in WUE. Thus, drought tolerance under stress conditions may exhibit a degree of predictability. Therefore, a dry stress experiment is planned to test the two contrasting clones.
KeywordsPoplar Photosynthesis Light response Water use efficiency Wood density
This project was funded and supported by the BMELV, German Agency for Renewable Resources (FNR) under FKZ: 22012510. Lucia Atanet Alia was the recipient of an FNR-research grant. We would like to thank Christine Ewald for her valuable knowledge and help with the establishment of plant material, measurement protocols and technical analysis methods.
- Ceulemans R, Isebrands JG (1996) Carbon acquisition and allocation. In: Stettler RF, Bradshaw HD Jr, Heilman PE, Hinckley TM (eds) Biology of Populus. NRC Research Press, Ottawa, pp 355–399Google Scholar
- Chaves MM, Osirio J, Pereira JS (2000) Water use and photosynthesis. In: Bacon MA (ed) Water use efficiency in plant biology. Blackwell Publishing, Oxford, pp 42–74Google Scholar
- Dickmann DI, Keathley DE (1996) Linking physiology, molecular genetics, and the Populus ideotype. In: Stettler RF, Bradshaw HD Jr, Heilman PE, Hinckley TM (eds) Biology of Populus. NRC Research Press, Ottawa, pp 491–514Google Scholar
- Dijkstra P (1990) Cause and effects of differences in specific leaf area. In: Lambers H (ed) Causes and consequences of variation in growth rate and productivity of higher plants. SPB Academic publishing, Hague, Netherlands, pp 125–140Google Scholar
- Marron N, Dreyer E, Boudouresque E, Delay D, Petit JM, Delmotte FM, Brignolas F (2003) Impact of successive drought and re-watering cycles on growth and specific leaf area of two Populus × canadensis (Moench) clones, ‘Dorskamp’ and ‘Luisa_Avanzo’. Tree Physiol 23:1225–1235CrossRefPubMedGoogle Scholar
- Qi C, Jin C, Kailong L (2010) Comparison of photosynthesis characteristics between different ploidies of Populus ussuriensis Kom. Plant Physiol J 46:917–922Google Scholar
- Schildbach M, Wolf H, Hartmann K-U (2012) Untersuchungen zur abiotischen Resistenz schnellwachsender Baumarten. In: Züchtung und Ertragsleistung schnellwachsender Baumarten im Kurzumtrieb—Erkenntnisse aus drei Jahren FastWOOD, ProLoc und Weidenzüchtung. Beiträge aus der Nordwestdeutschen Forstlichen Versuchsanstalt, vol. 8, Hann. Münden, Germany, pp 237–256Google Scholar
- Schulte M, Offer C, Hansen U (2003) Induction of CO2 gas exchange and electron transport: comparison of dynamic and steady-state responses in Fagus sylvatica leaves. Trees 17:153–163Google Scholar
- Soolanayakanahally RY, Guy RD, Silim SN, Drewes EC, Schroeder WR (2009) Enhanced assimilation rate and water use efficiency with latitude through increased photosynthetic capacity and internal conductance in balsam poplar (Populus balsamifera L.). Plant Cell Environ 32:1821–1832CrossRefPubMedGoogle Scholar
- US Environmental Protection Agency (1999) Biological aspects of hybrid poplar cultivation on floodplains in Western North America—a review. (EPA Document No. 910-R-99-002)Google Scholar
- Zhao S (2006) Nitrogen nutrition of hybrid poplars. Master Thesis, Washington State University, p 46Google Scholar