Timiryazev Institute of Plant Physiology, Russian Academy of Sciences, Moscow, Russia.
Moscow State University, Moscow, Russia.
Photosynth Res. 2019 Mar;139(1-3):307-323. doi: 10.1007/s11120-018-0520-1. Epub 2018 May 19.
We investigated the influence of 40 days of drought on growth, storage processes and primary photosynthetic processes in 3-month-old Scots pine and Norway spruce seedlings growing in perlite culture. Water stress significantly affected seedling water status, whereas absolute dry biomass growth was not substantially influenced. Water stress induced an increase in non-structural carbohydrate content (sugars, sugar alcohols, starch) in the aboveground part of pine seedlings in contrast to spruce seedlings. Due to the relatively low content of sugars and sugar alcohols in seedling organs, their expected contribution to osmotic potential changes was quite low. In contrast to biomass accumulation and storage, photosynthetic primary processes were substantially influenced by water shortage. In spruce seedlings, PSII was more sensitive to water stress than PSI. In particular, electron transport in PSI was stable under water stress despite the substantial decrease of electron transport in PSII. The increase in thermal energy dissipation due to enhancement of non-photochemical quenching (NPQ) was evident in both species under water stress. Simultaneously, the yields of non-regulated energy dissipation in PSII were decreased in pine seedlings under drought. A relationship between growth, photosynthetic activities and storage processes is analysed under weak water deficit.
我们研究了 40 天干旱对珍珠岩培养的 3 个月大小的欧洲赤松和挪威云杉幼苗生长、储存过程和初级光合作用的影响。水分胁迫显著影响了幼苗的水分状况，而绝对干生物量的生长并没有受到很大影响。与云杉幼苗相比，水分胁迫诱导了松树苗地上部分的非结构性碳水化合物含量（糖、糖醇、淀粉）的增加。由于幼苗器官中糖和糖醇的含量相对较低，它们对渗透势变化的预期贡献相当低。与生物量积累和储存不同，光合作用的初级过程受到水分短缺的显著影响。在云杉幼苗中，与 PSI 相比，PSII 对水分胁迫更为敏感。特别是，尽管 PSII 的电子传递显著减少，但PSI 中的电子传递在水分胁迫下仍保持稳定。在两种物种中，由于非光化学猝灭（NPQ）的增强导致热能耗散的增加是明显的。同时，在干旱条件下，松树苗 PSII 中非调节能量耗散的产量下降。在弱水分亏缺下，对生长、光合作用和储存过程之间的关系进行了分析。
