摘要
盆栽试验在高磷 (+P)和低磷 (-P)条件下 ,于四叶期测定了磷高效利用型玉米KH5和磷低效利用型玉米齐2 0 1的老叶 (第 2叶 )和新展开叶的 (第 4叶 )叶绿素荧光诱导动力学参数。结果表明 ,低磷处理使玉米叶片PSⅡ关闭程度增加、光能转换和电子传递效率降低 ,过剩激发能增加。基因型间比较 ,磷高效利用型玉米的光能转换和电子传递效率高于磷低效利用型玉米 ,且受低磷胁迫的影响较小。对低磷处理引起的过剩激发能 ,磷高效利用型玉米主要通过热耗散途径消耗 ,而磷低效利用型玉米的热耗散作用减弱 ,其他耗能机制加强。叶片含磷量与叶绿素最大光化学效率 (Fv Fm)符合y =7.5 9× (0 .0 9-e- 59.4 6x)指数函数关系 ,含磷量 0 .1mg·g- 1 FW是影响Fv Fm
Chlorophyll fluorescence of old (2nd) and newly expanded (4th) leaf of KH5 and Q201, which belong to high phosphate use efficiency (PE) and low PE genotype maize inbred lines respectively, grown at high (+P) and low (-P) phosphorus conditions, were determined at 4th leaf expanded stage. The results showed that low phosphorus stress caused the increase in close degree of PSⅡ reaction center, decrease in efficiency of light energy transformation and electron transportation, and increase in excessive excited energy. With compared to low PE genotype maize (Q201), the efficiency of light energy transformation and electron transportation was higher in high PE one (KH5), and less affected by low P stress. For the dissipation of excessive excited energy, thermal energy dissipation through antenna pigments were enhanced in high PE genotype maize (KH5), whereas in low PE ones(Q201) thermal energy dissipation was weakened, and other ways of energy dissipation were enhanced. The relationship between leave P content and F v/ F m fits a exponential curve ( y =7.59×(0.09- e -59.46 x ) ) significantly, and 0.1 mg·g -1 FW was the threshold for leaves P content affecting F v/ F m, F v/ F m would be decreased dramatically when leave P content below this threshold.
出处
《作物学报》
CAS
CSCD
北大核心
2004年第4期365-370,共6页
Acta Agronomica Sinica
基金
山东省良种产业化资助项目 ( 3 0 0 2 5 )
关键词
低磷胁迫
玉米
叶绿素荧光参数
磷效率
基因型
Maize ( Zea mays L.)
Phosphate efficiency
Genotype
Low phosphorus stress
Chlorophyll fluorescence
