Lu Chunyun, Wang Xiurong, Zhao Yang, Zou Rong, Xiao Feng
Institute for Forest Resources and Environment of Guizhou, College of Forestry, Guizhou University, Guiyang, 550025, Guizhou, China.
Sci Rep. 2024 Dec 30;14(1):31716. doi: 10.1038/s41598-024-82071-w.
This study aims to explore the low phosphorus (P) tolerance of saplings from different Gleditsia sinensis Lam. families. It also seeks to screen for Gleditsia sinensis families with strong low P tolerance and identify key indicators for evaluating their tolerance. This research provides a foundation for the breeding of superior families of Gleditsia sinensis and the study of mechanisms underlying low P tolerance. Using saplings from 30 Gleditsia sinensis families as the research subjects, a sand culture pot experiment was conducted. This study set up low P treatment (0.01 mmol L) and normal P treatment (1 mmol L). Twenty-five indicators including growth morphology, biomass, root morphology, and P content were measured. The low P tolerance coefficient was used as the basic data for assessing the low P tolerance of Gleditsia sinensis. The fuzzy comprehensive evaluation method was employed to comprehensively assess the low P tolerance types of Gleditsia sinensis a stepwise regression model was established to identify the key evaluation indicators for low P tolerance. The results indicate that low P stress reduced plant height, stem diameter, and biomass in most Gleditsia sinensis families, but increased the root morphological indicators, root-shoot ratio and PUE of various organs. Principal component analysis transformed the 25 indicators into 6 independent comprehensive indicators, with a cumulative contribution rate of 86.743%. The fuzzy comprehensive evaluation method calculated a comprehensive evaluation value (D value), enabling the screening of Gleditsia sinensis families into low P tolerant and low P sensitive types. Cluster analysis grouped the 30 Gleditsia sinensis families into 4 types. Among them, F13, F10, F9, F18, F15, and F28 were classified as low P tolerant types; F6, F23, F3, F17, F20, F2, F12, F11, F16, F8, F5, F27, F1, and F26 were categorized as intermediate types; F30, F7, F22, F4, F19, F29, F24, F14 and F25 were considered low P sensitive types, and F21 was classified as extremely low P sensitive types. The stepwise regression analysis identified the indicators stem diameter, total root volume, shoot dry weight, total root projection area, and leaf P content as the key factors for discriminating the low P tolerance of Gleditsia sinensis. The regression model is as follows: D=-0.005 + 0.323 stem diameter +0.154 * total root volume + 0.196 shoot dry weight + 0.139* total root projection area - 0.112* leaf P content. In summary, low P stress inhibited the growth of Gleditsia sinensis saplings, but it increased the root morphological indicators, root-shoot ratio and PUE of various organs to cope with low P environments. The screening identified F13, F10, F9, F18, F15, and F28 as low P tolerant Gleditsia sinensis families. The evaluation indicators for low P tolerance in Gleditsia sinensis were identified as stem diameter, total root volume, shoot dry weight, total root projection area and leaf P content.
本研究旨在探究不同皂荚（Gleditsia sinensis Lam.）家系幼树的耐低磷特性。同时，筛选耐低磷能力强的皂荚家系，并确定评价其耐低磷能力的关键指标。本研究为皂荚优良家系选育及耐低磷机制研究提供了依据。以30个皂荚家系的幼树为研究对象，进行砂培盆栽试验。本研究设置了低磷处理（0.01 mmol/L）和正常磷处理（1 mmol/L）。测定了包括生长形态、生物量、根系形态和磷含量等25项指标。以耐低磷系数作为评价皂荚耐低磷能力的基础数据。采用模糊综合评价法对皂荚的耐低磷类型进行综合评价，建立逐步回归模型以确定耐低磷的关键评价指标。结果表明，低磷胁迫降低了大多数皂荚家系的株高、茎径和生物量，但增加了各器官的根系形态指标、根冠比和磷利用效率。主成分分析将25项指标转化为6个独立的综合指标，累积贡献率为86.743%。模糊综合评价法计算出综合评价值（D值），从而将皂荚家系筛选为耐低磷型和低磷敏感型。聚类分析将30个皂荚家系分为4类。其中，F13、F10、F9、F18、F15和F28被归为耐低磷型；F6、F23、F3、F17、F20、F2、F12、F11、F16、F8、F5、F27、F1和F26被归为中间型；F30、F7、F22、F4、F19、F29、F24、F14和F25被认为是低磷敏感型，F21被归为极低磷敏感型。逐步回归分析确定茎径、总根体积、地上部干重、总根投影面积和叶片磷含量为判别皂荚耐低磷能力的关键因素。回归模型如下：D = -0.005 + 0.323×茎径 + 0.154×总根体积 + 0.196×地上部干重 + 0.139×总根投影面积 - 0.112×叶片磷含量。综上所述，低磷胁迫抑制了皂荚幼树的生长，但增加了各器官的根系形态指标、根冠比和磷利用效率，以应对低磷环境。筛选出F13、F10、F9、F18、F15和F28为耐低磷皂荚家系。确定皂荚耐低磷的评价指标为茎径、总根体积、地上部干重、总根投影面积和叶片磷含量。
