贵州地方稻种来拢黄叶突变体yl-1光合特性研究

The Photosynthetic Characteristics of Leaf Color Mutants of Guizhou landrace Cultivar Rice Lailong

本研究利用化学诱变剂甲基黄酸乙脂(EMS)处理贵州禾来拢,从M2代中筛选出一份黄叶突变体yl-1。在贵阳和三亚连续自交5代,其突变性状和各种农艺性状均已稳定。使用LI-6400便携式光合作用测量系统对黄叶突变体yl-1进行光合特性分析。结果表明,与野生型相比,突变体yl-1孕穗期的叶绿素a、叶绿素b和类胡萝卜素含量分别为野生型的62.30%、41.07%和75.64%;在强光条件下(12:00-14:00),突变体yl-1的光合速率显著高于野生型,且没有出现"午休现象";突变体yl-1的初始荧光产量(Fo)为野生型的72.50%,最大光合效率(Fv/Fm)比野生型高4.17%,光化学淬灭(qP),电子传递速率(ETR)和PSII的光化学效率(ΦPSII)分别比野生型高10.61%、36.34%和37.03%,而非光化学淬灭(qN)下降比野生型下降2.38%。结果说明突变体yl-1比野生型有更强的活性氧清除能力;在强光条件下没有"午休现象",而且有更高的光合速率。突变体yl-1不仅可作为标记性状在杂种优势中加以应用,还可以应用到水稻的高光效育种中。

The yellow leaf mutant yl-1 was identified from Guizhou native rice variety Lailong M2 generation which was treated by chemical mutagen EMS. The mutant and various agronomic traits had been stable after 5 successive inbreeding at the Guiyang and Sanya. The photosynthetic characteristics ofyl-1 mutant were analyzed using LI-6400 portable photosynthesis system. Resultantly, the content of chlorophyll a, chlorophyll b and carotenoid of yl-1 mutant were 62.30% ,41.07%, 75.64% compared with wild type at the booting stage, respectively; In bright light conditions （12：00-14：00）, the net photosynthetic rate of yl-1 mutant was higher than that of wild type significantly and not exhibited ＂Midday depression＂ phenomenon; The initial fluorescence yield （Fo） of y 1-1 mutant was 72.50% compared with wild type, the maximum photosynthetic efficiency （Fv/Fm） was 4.17% higher than wild type, photochemical quenching （qP）, electron transport rate （ETR） and photochemical efficiency of PSII （ФPSII） were 10.61%, 36.34%, 37.03% higher than the wild type, respectively. Meanwhile, the non-photochemical quenching （qN） decreased 2.38% over the wild type. This suggested that the reactive oxygen species scavenging ability of yl-I mutant was stronger than wild type and had a higher net photosynthetic rate, no ＂Midday depression＂ phenomenon in bright light conditions. The yl-l mutant can not only be applied as a marker trait heterosis in rice but also can be applied to high photosynthetic efficiency breeding.