Madhana Sekhar Kalva, Rachapudi Venkata Sreeharsha, Mudalkar Shalini, Reddy Attipalli Ramachandra
Department of Plant Sciences, University of Hyderabad, Hyderabad 500046, India.
Department of Plant Sciences, University of Hyderabad, Hyderabad 500046, India.
J Photochem Photobiol B. 2014 Aug;137:21-30. doi: 10.1016/j.jphotobiol.2014.05.001. Epub 2014 May 23.
Current study was undertaken to elucidate the responses of short rotation coppice (SRC) mulberry under elevated CO2 atmosphere (550μmolmol(-1)). Throughout the experimental period, elevated CO2 grown mulberry plants showed significant increase in light saturated photosynthetic rates (A') by increasing intercellular CO2 concentrations (Ci) despite reduced stomatal conductance (gs). Reduced gs was linked to decrease in transpiration (E) resulting in improved water use efficiency (WUE). There was a significant increase in carboxylation efficiency (CE) of Rubisco, apparent quantum efficiency (AQE), light and CO2 saturated photosynthetic rates (AMAX), photosynthetic nitrogen use efficiency (PNUE), chlorophyll a fluorescence characteristics (FV/FM and PIABS), starch and other carbohydrates in high CO2 grown plants which clearly demonstrate no photosynthetic acclimation in turn resulted marked increase in above and below ground biomass. Our results strongly suggest that short rotation forestry (<1year) with mulberry plantations should be effective to mitigate raising CO2 levels as well as for the production of renewable bio-energy.
本研究旨在阐明短轮伐期矮林（SRC）桑树在二氧化碳浓度升高（550μmolmol⁻¹）环境下的响应。在整个实验期间，尽管气孔导度（gs）降低，但二氧化碳浓度升高环境下生长的桑树通过增加细胞间二氧化碳浓度（Ci），使光饱和光合速率（A'）显著提高。gs降低与蒸腾作用（E）下降有关，从而提高了水分利用效率（WUE）。高二氧化碳浓度环境下生长的植株中，核酮糖-1,5-二磷酸羧化酶的羧化效率（CE）、表观量子效率（AQE）、光饱和与二氧化碳饱和光合速率（AMAX）、光合氮利用效率（PNUE）、叶绿素a荧光特性（FV/FM和PIABS）、淀粉及其他碳水化合物均显著增加，这清楚地表明没有光合适应现象，进而导致地上和地下生物量显著增加。我们的结果有力地表明，种植桑树的短轮伐期林业（<1年）对于缓解不断上升的二氧化碳水平以及生产可再生生物能源应是有效的。
