The effects of localized heating and disbudding on cambial reactivation and formation of earlywood vessels in seedlings of the deciduous ring-porous hardwood, Quercus serrata
The effects of localized heating and disbudding on cambial reactivation and formation of earlywood vessels in seedlings of the deciduous ring-porous hardwood, Quercus serrata
复制标题
局部加热和除芽对落叶环孔阔叶栎幼苗形成层再激活和早材导管形成的影响
DOI：
10.1093/aob/mcu026
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发表时间：
2014
期刊：
影响因子：
4.2
通讯作者：
Ryo Funada
中科院分区：
文献类型：
--
作者：
Kayo Kudo;Eri Nabeshima;Shahanara Begum;Yusuke Yamagishi;Satoshi Nakaba;Yuichiro Oribe;Ko Yasue;Ryo Funada
背景和目的导管元件网络在水从根部到叶片的运输中起着至关重要的作用，早材导管的持续形成对于环孔硬木的生长至关重要。早材导管的分化受外部和内部因素控制。本研究旨在通过对落叶环孔硬木栎树幼苗的休眠茎进行局部加热和除芽来确定诱导形成层再激活和早材导管分化的限制因素。方法通过在茎上缠绕电加热带来实现局部加热。去芽涉及去除所有芽。 2012年2月1日开始进行三种处理，即加热、除芽和加热与除芽结合，以未处理的休眠茎作为对照。通过光学和偏光显微镜监测形成层的再激活和导管元件的分化，并跟踪芽的生长。关键结果在发芽前，加热的幼苗中的形成层再激活和导管元件的分化比未加热的幼苗发生得更快。与未加热的幼苗相比，幼苗的加热和除芽的结合还导致较早的形成层重新激活和第一导管元件的分化。脱蕾后的加热过程中形成了少量狭窄的导管分子，而带芽加热的幼苗则形成了许多较大的早材导管分子。结论结果表明，在落叶环孔阔叶栎幼苗中，升高的温度是形成层重新激活和第一导管分子分化的直接触发因素。芽的生长对于形成层的重新激活和第一导管元件的分化不是必需的，但对于宽导管元件的连续形成可能很重要。
Background and AimsThe networks of vessel elements play a vital role in the transport of water from roots to leaves, and the continuous formation of earlywood vessels is crucial for the growth of ring-porous hardwoods. The differentiation of earlywood vessels is controlled by external and internal factors. The present study was designed to identify the limiting factors in the induction of cambial reactivation and the differentiation of earlywood vessels, using localized heating and disbudding of dormant stems of seedlings of a deciduous ring-porous hardwood,Quercus serrata.MethodsLocalized heating was achieved by wrapping an electric heating ribbon around stems. Disbudding involved removal of all buds. Three treatments were initiated on 1 February 2012, namely heating, disbudding and a combination of heating and disbudding, with untreated dormant stems as controls. Cambial reactivation and differentiation of vessel elements were monitored by light and polarized-light microscopy, and the growth of buds was followed.Key ResultsCambial reactivation and differentiation of vessel elements occurred sooner in heated seedlings than in non-heated seedlings before bud break. The combination of heating and disbudding of seedlings also resulted in earlier cambial reactivation and differentiation of first vessel elements than in non-heated seedlings. A few narrow vessel elements were formed during heating after disbudding, while many large earlywood vessel elements were formed in heated seedlings with buds.ConclusionsThe results suggested that, in seedlings of the deciduous ring-porous hardwoodQuercus serrata, elevated temperature was a direct trigger for cambial reactivation and differentiation of first vessel elements. Bud growth was not essential for cambial reactivation and differentiation of first vessel elements, but might be important for the continuous formation of wide vessel elements.