棉花早熟芽黄突变体叶绿素荧光动力学特性研究

以中棉所58及其航天诱变芽黄突变体为研究对象,利用快速叶绿素荧光诱导动力学测定和JIP-test数据分析方法,研究了晴天条件下野生型(Wild type,WT)和突变体5个叶位叶片(倒1叶至倒5叶)的原初光化学反应的变化.结果表明,突变体倒2叶最大光化学效率(Fv/Fm)最低,至倒5叶时恢复正常.突变体叶片较高的K点的...

Research of Chlorophyll Fluorescence Dynamic Characteristic in A Cotton Virescent Mutant

In this research, CCRI 58 and its space virescent mutant vsp were used as materials to analyze the change of primary photochemical of different position leaves(the first to the fifth leaves from the top) by chlorophyll a fluorescence transient measurement and the relevantly analytical method, JIP-test on sunny days. The results showed that the maximum photochemical efficiency of photosystem Ⅱ(F_v/F_m) and performance index(PI_ABS) displayed a tendency of progressive increase in the wild type from the first leaf from the top to the fifth leaf from the top, while in the mutant, the young leaves contained less chlorophyll , and the value of F_v/F_m and PI_ABS in the second leaf from the top showed the lowest level, then increased to normal level 10 days later(the fifth leaf from the top). Compared to the wild type, the high relative variable fluorescence intensity of K-step (W_k) in the young leaves meant that the oxygen-evolving complex(OEC) got damaged, and the increasing of approximated initial slope of the fluorescence transient (M_o), the reduction of normalized total complementary area above the O-J-I-P transient(S_m), quantum yield for electron transport(φ_Eo), probability that a trapped exciton moves an electron into the electron transport chain beyond QA-(ψ_o) revealed that the Q_A^- accumulation was excessive in the acceptor side of PSⅡ, the electron transport chain got blocked. The changes in the parameters of absorption flux per reaction center (ABS/RC), trapped energy flux per reaction center (TR_o/RC), electron transport flux per reaction center (ET_o/RC), dissipated energy flux per reaction center (DI_o/RC) showed that, in the early development of the leaf, the energy absorbed by reaction center was dissipated through heat and fluorescence. Above all, we speculated that because of the block of the chlorophyll biosynthesis at the early development of the young true leaves, the PSⅡgot damaged and showed lower photochemical reaction efficiency.