空中甘薯嫁接栽培系统结薯关键期叶绿素荧光特性研究

Chlorophyll Fluorescence of Key Stages of Storage Roots Formation in Grafted Overhead-sweetpotato Cultivation System

为了分析空中甘薯嫁接栽培系统在块根形成关键过程中的光合能力变化情况,利用MINI-IMAGING-PAM叶绿素荧光仪测定了该时期的叶绿素荧光参数。结果表明,在压蔓0~20 d藤蔓长根期,最大光化学效率（Fv/Fm）和PSII实际光化学效率（YieldⅡ）下降、非光化学猝灭系数（NPQ）升高、表观光合电子传递速率（ETR）先增后降;压蔓20~45 d须根开始膨大,Fv/Fm、YieldⅡ和ETR持续增高,NPQ则先降后增,说明PSII反应中心的能量捕获效率增高,光合能力提高;压蔓45~60 d,光合能力又有降低。

To reveal the effects of chlorophyll fluorescence of key stages of storage roots formation in grafted overhead-sweetpotato cultivation（ GOSC） system,the chlorophyll fluorescence was measured in this stage by Chlorophyll fluorescence spectrometer MINI-IMAGING-PAM（ Walz,Germany）. In the stage of 0-20 days after burying stem of fibrous roots growing,the maximal photochemical efficiency（ Fv/ Fm）and the effective quantum yield of photosystem II（ YieldⅡ） decreased,the non-photochemical quenching（ NPQ） increased,and the nonphotochemical quenching（ ETR） increased first then decreased. In the stage of 20- 45 days after burying stem of fibrous roots swollen to storage roots,the Fv/ Fm,YieldⅡand ETR increased continuously,but the NPQ decreased first then increased,indicating the increasing of excitation energy capture by open PS Ⅱ reaction centers of leaves and improving photosynthetic capacity. But 45- 60 days after burying stem,the photosynthetic capacity decreased.