Halmagyi A, Surducan E, Surducan V
National Institute of Research and Development for Biological Sciences, Branch Institute of Biological Research, Republicii Street 48, 400015, Cluj-Napoca, Romania.
National Institute of Research and Development for Isotopic and Molecular Technologies, Donat Street 67-103, 400293, Cluj-Napoca, Romania.
J Biol Phys. 2017 Sep;43(3):367-379. doi: 10.1007/s10867-017-9457-4. Epub 2017 Jun 24.
Two distinct microwave power levels and techniques have been studied in two cases: low-power microwave (LPM) irradiation on in vitro Sequoia plants and high-power microwave (HPM) exposure on recovery rates of cryostored (-196°C) Sequoia shoot apices. Experimental variants for LPM exposure included: (a) in vitro plants grown in regular conditions (at 24 ± 1°C during a 16-h light photoperiod with a light intensity of 39.06 μEm s photosynthetically active radiation), (b) in vitro plants grown in the anechoic chamber with controlled environment without microwave irradiation, and (c) in vitro plants grown in the anechoic chamber with LPM irradiation for various times (5, 15, 30, 40 days). In comparison to control plants, significant differences in shoot multiplication and growth parameters (length of shoots and roots) were observed after 40 days of LPM exposure. An opposite effect was achieved regarding the content of total soluble proteins, which decreased with increasing exposure time to LPM. HPM irradiation was tested as a novel rewarming method following storage in liquid nitrogen. To our knowledge, this is the first report using this type of rewarming method. Although, shoot tips subjected to HPM exposure showed 28% recovery following cryostorage compared to 44% for shoot tips rewarmed in liquid medium at 22 ± 1 °C, we consider that the method represent a basis and can be further improved. The results lead to the overall conclusion that LPM had a stimulating effect on growth and multiplication of in vitro Sequoia plants, while the HPM used for rewarming of cryopreserved apices was not effective to achieve high rates of regrowth after liquid nitrogen exposure.
对离体红杉植物进行低功率微波（LPM）照射，以及对冷冻保存（-196°C）的红杉茎尖恢复率进行高功率微波（HPM）照射。LPM照射的实验变体包括：（a）在常规条件下生长的离体植物（在16小时光照周期、光照强度为39.06 μEm⁻² s⁻¹光合有效辐射下，温度为24±1°C），（b）在无微波照射的可控环境消声室内生长且无微波照射的离体植物，以及（c）在消声室内接受不同时长（5、15、30、40天）LPM照射的离体植物。与对照植物相比，LPM照射40天后，在嫩枝增殖和生长参数（嫩枝和根的长度）方面观察到显著差异。在总可溶性蛋白含量方面则出现相反的效果，其随LPM暴露时间的增加而降低。HPM照射作为液氮保存后的一种新型复温方法进行了测试。据我们所知，这是首次使用这种复温方法的报告。尽管，与在22±1°C的液体培养基中复温的茎尖相比，接受HPM照射的茎尖在冷冻保存后的恢复率为28%，而前者为44%，但我们认为该方法具有基础价值且可进一步改进。结果得出总体结论，即LPM对离体红杉植物的生长和增殖有刺激作用，而用于冷冻保存茎尖复温的HPM在液氮暴露后未能有效实现高再生率。
