短日照对休眠诱导期油桃花芽两条电子传递途径的调控

Regulation effects of short sunlight on two electron transport pathways in nectarine flower bud during dormancy induction.

以油桃品种"曙光"为试材,采用呼吸抑制剂法研究了短日照处理下花芽在休眠诱导期两条电子传递途径的发生和运行情况.结果表明:花芽总呼吸速率(Vt)和细胞色素电子传递途径呼吸速率(ρ’Vcyt)均呈双峰曲线变化,短日照可同步诱导两者的一次峰前移、二次峰后延,抑制ρ’Vcyt,但对Vt无显著影响.交替途径容量(Valt)和实际运行活性(ρValt)亦呈双峰曲线,两者基本同步变化,短日照可以显著诱导Valt和ρValt的前期高峰期提前,提高Valt和ρValt,对后期高峰期无明显作用.细胞色素电子传递途径呼吸速率下降和交替途径呼吸速率上升是油桃花芽休眠诱导期的重要特点.从两条电子传递途径的呼吸速率对总呼吸速率的贡献率来看,细胞色素电子传递途径仍是主要电子传递途径,交替途径起辅助与分流作用.

Taking the nectarine variety ＇Shuguang＇（Prunus persica var.nectariana cv.Shuguang） as test material,and by using respiration inhibitors KCN and SHAM,this paper studied the cytochrome electron transport pathway and the alternative respiration pathway in nectarine flower bud during dormancy induction under the effects of short sunlight.Both the total respiration rate（Vt） and the cytochrome electron transport pathway respiration rate（ρ＇Vcyt） presented double hump-shaped variation.Short sunlight brought the first-hump of Vt and ρ＇Vcyt forward and delayed the second-hump synchronously,inhibited the ρ＇Vcyt,but had no significant effects on the Vt.The capacity（Valt） and activity（ρValt） of alternative respiration pathway also varied in double hump-shape,and the variation was basically in synchronous.Short sunlight made the first climax of Valt and ρValt advanced,but had little effects on the later period climax.The inhibition of cytochrome electron transport pathway and the enhancement of alternative respiration pathway were the important features of nectarine flower bud during dormancy induction,and according to the respective contributions of the two electron transport pathways to the total respiration rate,the cytochrome electron transport pathway was still the main pathway of electron transport,whereas the alternative respiration pathway played an auxiliary and branched role.