甘蔗抗旱性生理生化鉴定指标

Physiological and biochemical indexes of drought resistance of sugarcane (Saccharum spp.)

利用因子分析和灰色关联度分析方法研究了甘蔗叶片相对含水量、膜脂过氧化代谢、活性氧代谢、光合参数及蔗茎产量性状等指标与抗旱性的关系.结果表明,干旱胁迫下甘蔗叶片的MDA含量和PMP明显提高,而RWC、SOD活性、Chl含量、Fv/Fm、Fv/Fo、△Fv/Ft、△Fv/Fo和蔗茎单茎重(SSW)8个抗旱性指标均显著降低.SSW与其它9个生理生化指标的相关性大小依次为PMP>SOD活性>MDA含量>RWC>Fv/Fo>Fv/Fm>Chl含量>ΔFv/Fo>ΔFv/Ft,其中,SSW与ΔFv/Fo和ΔFv/Ft相关性不显著.通过因子分析将10个甘蔗抗旱性指标用4个公共因子表示,累加方差贡献率达到92·08%.因子l主要是反映光合作用特性指标对甘蔗品种抗旱性起支配作用,因子2主要是反映叶片相对含水量及活性氧代谢指标对甘蔗品种抗旱性起支配作用,因子3和因子4分别只有SSW和Chl含量有较大载荷.灰色关联度分析表明,各抗旱性生理生化指标与SSW关联密切程度依次为Fv/Fm>PMP>Fv/Fo>RWC>MDA含量>SOD活性>ΔF/F>Chl含量>ΔF/F.

Through factor analysis and grey correlative degree analysis, this paper studied the relationships of sugarcane leaf relative water content （RWC）, membrane lipid peroxidation metabolism, active oxygen metabolism, photosynthesis, and stalk yield with drought resistance of sugarcane. The results suggested that under drought stress, the plasma membrane permeability （PMP） and malondialdehyde （MDA） content were markedly increased, while RWC, superoxide dismutase （SOD） activity, chlorophyll （Chl） content, PSⅡ photochemical efficiency （ Fv/ Fm）, PS Ⅱ potential activity （ Fv/Fo ）, variable fluorescence quenching rate （△Fv/Fo）, efficiency of potential quantum conversion （△Fv/Ft）, and single stalk weight （SSW） were remarkably decreased. The correlation of SSW with test indexes was decreased in the order of PMP, SOD activity, MDA content, RWC, Fv/Fo, Fv/Fm, Chl content, △Fv/Fo and △Fv/Ft, Through factor analysis, the test indexes were divided into four common factors, among which, the indexes of photosynthesis played important roles in the iirst factor, RWC and the indexes of active oxygen metabolism dominated in the second factor, while SSW and Chl content played primary roles in the third and fourth factor, respectively. The grey correlative degree of SSW with other indexes was in the rank of Fv/Fm, PMP, Fv/Fo, RWC, MDA content, SOD activity, △Fv/Ft, Chl content, and △Fv/Fo.