水稻突变体Shuanglimi的光合特性

摘要

以水稻突变体Shuanglimi为试验材料,对其幼穗处于减数分裂期时剑叶的净光合速率(Pn)、蒸腾速率(Tr)、叶片气孔导度(Gs)、胞间CO2浓度(Ci)、水分利用率(WUE)和羧化效率(CE)、叶绿素含量及剑叶中维管束数目进行了测定和观察.结果表明,Shuanglimi的Pn、WUE和CE较CK分别降低了(71.18±2.08)％,(72.00±2.51)％和(79.33±3.27)％(P＜0.01),而其Tr和Ci与CK之间无显著差异.Shuanglimi总叶绿素含量较CK降低,尤其是叶绿素b含量大幅降低.同时,Shuanglimi剑叶中小维管束的数目较CK降低了(18.86±1.97)％(P＜0.01),而大维管束中含有3个和4个导管的特异变化数目较CK明显增加.由此可见,Shuanglimi的光合特性差异是其子粒和生殖特性差异形成的原因之一.%A new rice mutant,Shuanglimi,was selected as the experiment material.The photosynthesis of flag leaves including net photosynthesis rate (Pn),transpiration rate (Tr),stomatal conductance (Gs),intercellular CO2 concentration(Ci),water use efficiency (WUE) and carboxylation efficiency (CE) were examined,and the concentration of chlorophyll and the number of vascular bundle were also measured when the spikelet of Shuanglimi was on the meiosis stage.The results showed that Pn,WUE and CE of Shuanglimi decreased by (71.18±2.08)％ (P＜0.01),(72.00±2.51)％ and (79.33±±3.27)％ (P＜0.01)compared with that of CK respectively,and T,and Ci had no significant difference.The chlorophyll content of Shuanglimi was less that that of CK,particularly,the concentration of chlorophyll b declined substantially.Meanwhile,the number of small vascular bundles in the flag leaves of Shuanglimi reduced by (18.86±1.97)％ (P＜0.01) compared with that of CK,and the number of big vascular bundles which included 3 or 4 vessels significantly increased.Therefore,it is the one of reasons that the differences of grain and reproduction of Shuanglimi are caused by the difference of photosynthesis characteristic.