不同种源马尾松种质耐低磷的主成分与灰色关联度分析

通过对不同种源马尾松在磷胁迫下多项形态和生理指标的测定,利用主成分和灰色关联分析,筛选和鉴定了耐低磷种源.以广西桐棉(GT)、福建龙岩(FL)、福建武平(FW)、江西崇义(JC)、湖南汝城(HR)、四川眉山(SM)及贵州孟关(GM)等7个种源的马尾松幼苗进行盆栽试验,采用营养液培养,设置正常磷条件(KH_2PO_4 10 mg/L,对照)和低磷(2.0 mg/L)处理,测定株高、主根长、根质量、地上部鲜质量、根冠比、总叶绿素、类胡萝卜素、可溶性糖、丙二醛、可溶性蛋白、游离脯氨酸、超氧化物歧化酶、过氧化物酶、过氧化氢酶和根系活力等15个形态生理指标,以各项指标的耐低磷系数作为耐低磷指标,通过主成分和灰色关联分析对其耐低磷进行评价.主成分分析将15个单项指标转换成4个综合指标;隶属函数法计算耐低磷能力D值为四川眉山(SM)最大;灰色关联分析表明类胡萝卜素质量分数、根系活力、丙二醛质量分数和游离脯氨酸质量分数与马尾松耐低磷性关系密切.综上,主成分和灰色关联分析能够有效用于马尾松耐低磷种质筛选,四川眉山种源较耐低磷,福建龙岩(FL)和福建武平(FW)属中等耐低磷类型,贵州孟关(GM)与江西崇义(JC),广西桐棉(GT)与湖南汝城(HR)属于较弱耐低磷类型.

Principal Component Analysis and Grey Correlation Analysis for Low Phosphorus Tolerance Evaluation in Masson Pine (Pinus massoniana) of Different Provenances

The morphological and physiological parameters of masson pine (Pinus massoniana) seedlings from different provenances under phosphorus stress were studied through principal component and grey correlation analyses to select germplasms with high tolerance to low phosphorus stress. Seedlings of seven masson pine provenances from Tongmian of Guangxi (GT), Longyan and Wuping of Fujian (FL and FW), Chongyi of Jiangxi (JC), Rucheng of Hunan(HR), Meishan of Sichuan (SM) and Mengguan of Guizhou (GM) were used as materials for a pot experiment with different phosphorus concentrations, i. e. normal phosphorus (KH2PO4 10 mg/L, control) and low phosphorus (KH2PO4 2.0 mg/L). Plant height, taproot length, root weight, fresh weight of the shoot, ratio of root to shoot, total chlorophyll content, carotenoids content, soluble sugars, MDA, soluble protein content, SOD activity, POD activity, CAT activity and root activity were determined. The low phosphorus tolerance coefficients of the above 15 morphological and physiological parameters were used as the indexes of tolerance to low phosphorus stress of the seedlings, and principal component analysis and grey correlation analysis were made to give a comprehensive evaluation. The principal component analysis classified the 15 single parameters into 4 independent comprehensive components. Based on the computation with the membership function method, SM had the maximum D value of tolerance to low phosphorus stress. Grey correlation analysis indicated that carotenoid content, root activity, MDA and free proline content were closely related to low phosphorus tolerance in masson pine. In conclusion, principal component analysis and grey correlation analysis could be effectively used for germplasm selection for high tolerance to low phosphorus stress in masson pine; of the 7 provenances studied SM had the highest tolerance to low phosphorus stress, followed by FL and FW, and GT and HR showed the lowest tolerance.