外源钙调控樟子松-外生菌根共生体适应干旱逆境的生理分子机制解析

Pinus sylvestris var. mongolica is a dominant species in Northeast forest. The rapid warming trend in northeast China in recent years made the sandy P. sylvestris var. mongolica forest located at Liaoning Northwest showed a trend of decline. The growth condition is bad, frequent occurrence of pest and disease even death. This brings enormous challenge to local environmental and ecological construction. Therefore, to improve the ability to resist drought environment of P. sylvestris var. mongolica is very important to maintain the regional ecological and environmental security. In this study, P. sylvestris var. mongolica was used. With exogenous calcium on " P. sylvestris var. mongolica - ectotrophic mycorrhiza" complex controlling effect as the core content in the research of drought resistance on the basis of previous studies. Using the seedling water use efficiency, cell production analysis, qRT-PCR, etc，in order to expound exogenous calcium on "P. sylvestris var. mongolica-ectotrophic mycorrhiza" complex regulation effect of drought tolerance from the growth, physiological and molecular levels. The study for Liaoning Northwest drought adversity survival rate of afforestation improving semi-arid areas to provide the reference, it also can find new breakthrough for the region P. sylvestris var. mongolica wither decline reason research at the same time.

樟子松（Pinus sylvestris var. mongolica）是我国北方主要造林树种。近年来气候变暖致使干旱加剧使得辽西北地区沙地樟子松呈现衰退趋势。樟子松生长状况不佳、病虫害频发甚至死亡，给当地环境治理与生态建设带来巨大挑战。因此，深入挖掘该地区樟子松抵御干旱环境的潜力，对于维护该区域生态具有重要意义。本研究以樟子松为研究对象，以外源钙对“樟子松-外生菌根”共生体耐旱性的调控效应为核心研究内容，在前期的研究基础上，通过苗木水分利用效率分析、细胞产物分析、荧光定量PCR等技术，从生长、生理和分子水平探讨干旱胁迫下，外源钙对菌根化樟子松苗木调控模式，阐明外源钙调控“樟子松-外生菌根”共生体响应干旱胁迫的生理分子机制。该研究可以为辽西北干旱-半干旱地区逆境造林提高成活率提供参考，同时为该地区樟子松衰退枯萎原因研究寻找新的突破点。

沙地樟子松是我国人工林体系中的重要树种。历经数十年的建设和发展，我国的人工林体系取得成绩的同时，各种问题也逐渐凸显。这其中，沙地樟子松的衰退问题是近些年的热点问题之一。本项目利用林木菌根学相关理论与实验技术，通过研究辽宁西部地区樟子松人工林外生菌根资源及相关菌根菌株筛选，探测外源钙存在条件下，樟子松-外生菌根共生体在土壤干旱水平下的生长规律，生理响应机制。进而研究了外源钙对樟子松-外生菌根共生体适应干旱逆境的相关策略。明确了外源钙对沙地樟子松抵御干旱逆境的正向调控作用，而这种作用在外生菌根的存在条件下，体现出较显著的“叠加效应”。本项目按原计划顺利执行，完成了执行期间的既定研究任务和人才培养计划，按照要求，探究了既定科学问题，积累并集成了基础研究数据，提出了施用一定浓度（≤0.02mmol·L-1）的外源钙对樟子松-外生菌根共生体抵御干旱胁迫的增强效应，即“钙+菌根”对于樟子松而言，为“1+1＞2”的关系。截止目前，该项目已资助完成论文8篇，其中SCI论文3篇，CSCD论文5篇，出版专著1部，授权专利2项，软件著作权1项。该研究可以为辽西北干旱-半干旱地区逆境造林提高成活率提供参考，同时为该地区樟子松衰退枯萎原因研究寻找新的突破点。