两种根砧嫁接‘洛阳红’光合特性与叶绿素荧光参数的比较

Comparison of photosynthetic characteristics and fluorescence parameters of grafted ‘Luoyang Hong’ on two rootstocks

【目的】对2种根砧嫁接的‘洛阳红’盆栽植株叶片的光合特性与叶绿素荧光参数季节性变化进行比较,筛选更适宜盆栽的嫁接‘洛阳红’砧木。【方法】以‘洛阳红’为接穗,芍药根和凤丹根为砧木,测定2种根砧嫁接‘洛阳红’叶片的净光合速率(P_n)、气孔导度(G_s)、胞间CO_2浓度(C_i)、蒸腾速率(T_r)、单叶瞬时水分利用效率(WUE)、羧化速率(CE)等光合特性以及初始荧光(F_0)、最大荧光(F_m)、PSⅡ的最大光化学效率(F_v/F_m)、PSⅡ的有效量子产量[Y(Ⅱ)]、光化学淬灭系数(qP)、非光化学淬灭系数(qN)等叶绿素荧光参数,并分析P_n与其他参数的相关性。【结果】盛花期至夏季休眠期,芍药砧‘洛阳红’叶片的P_n始终高于凤丹砧‘洛阳红’。圆桃期至盛花期,芍药砧‘洛阳红’叶片的P_n、CE、WUE、F_m、F_v/F_m、Y(Ⅱ)分别增长了145.86%,245.10%,60.68%,33.27%,8.45%和25.00%,增长幅度较凤丹砧‘洛阳红’大。花后生长期,芍药砧‘洛阳红’叶片qN显著高于凤丹砧‘洛阳红’。相关性分析表明,芍药砧和凤丹砧‘洛阳红’叶片的P_n与CE、T_r均呈极显著正相关,芍药砧‘洛阳红’的P_n与G_s呈显著正相关,凤丹砧‘洛阳红’的P_n与G_s呈极显著正相关;芍药砧‘洛阳红’P_n与F_v/F_m呈极显著正相关,凤丹砧‘洛阳红’P_n与F_v/F_m呈显著正相关,2种根砧‘洛阳红’P_n与Y(Ⅱ)均呈正相关关系,但均未达到显著水平。【结论】芍药砧嫁接‘洛阳红’叶片具有更高的光能利用效率,更适宜作为盆栽‘洛阳红’的砧木。

【Objective】 Seasonal changes of photosynthetic characteristics and chlorophyll fluorescence parameters in leaves of potted ‘Luoyang Hong’ grafted with two rootstocks were compared to select suitable potted rootstocks for grafted ‘Luoyang Hong’.【Method】 With the branches of Paeonia suffruticosa ‘Luoyang Hong’ as scion, roots of Paeonia broteri and Paeonia ostii were used as rootstocks to determine the photosynthetic characteristics including net photosynthetic rate ( P n ),stomatal conductance ( G s ),intercellular CO 2 concentration ( C i), transpiration rate ( T r ),and single leaf instantaneous water use efficiency ( WUE ) as well as chlorophyll fluorescence parameters including initial fluorescence ( F 0),maximum fluorescence ( F m ),maximum photochemical efficiency of PSⅡ( F v/F m ),effective quantum yield of PSⅡ[ Y (Ⅱ)], photochemical quenching coefficient ( qP ),and non-photochemical quenching coefficient ( qN).The correlation of P n with other parameters was also analyzed.【Result】 From the full flowering stage to the summer dormancy stage,the P n of ‘Luoyang Hong’ grafted on Paeonia broteri root was higher than that on Paeonia ostii root.From the round peach stage to the full flowering stage, P n,CE,WUE,F m,F v/F m, and Y (Ⅱ) of ‘Luoyang Hong’ grafted on Paeonia broteri root were increased by 145.86%,245.10%, 60.68%, 33.27%,8.45% and 25.00%,all were larger than that of Paeonia ostii. In the post-anthesis growth stage, qN of ‘Luoyang Hong’ grafted on Paeonia broteri root was significantly higher than that on Paeonia ostii. The correlation analysis showed that P n of tree peony grafted on Paeonia broteri and Paeonia ostii was significantly and positively correlated with CE and T r.P n of tree peony grafted on Paeonia broteri was significantly positively correlated with G s and P n of tree peony grafted on Paeonia ostii was positively correlated with that of G s. There was a significantly positive correlation between P n and F v/F m of ‘Luoyang Hong’ grafted on Paeonia broteri ,and P n of tree peony grafted on Paeonia ostii was positively correlated with F v/F m.P n of the two grafted ‘Luoyang Hong’ was positively related to Y (Ⅱ) insignificantly.【Conclusion】 The leaves of ‘Luoyang Hong’ grafted on Paeonia broteri root had higher light energy utilization efficiency and Paeonia broteri roots are more suitable as rootstock for potted ‘Luoyang Hong’.