Department of Biology, University of Essex, CO4 3SQ, Colchester, UK.
Photosynth Res. 1994 Oct;42(1):17-25. doi: 10.1007/BF00019054.
The light harvesting and photosynthetic characteristics of a chlorophyll-deficient mutant of cowpea (Vigna unguilata), resulting from a single nuclear gene mutation, are examined. The 40% reduction in total chlorophyll content per leaf area in the mutant is associated with a 55% reduction in pigment-proteins of the light harvesting complex associated with Photosystem II (LHC II), and to a lesser extent (35%) in the light harvesting complex associated with Photosystem I (LHC I). No significant differences were found in the Photosystem I (PS I) and Photosystem II (PS II) contents per leaf area of the mutant compared to the wildtype parent. The decreases in the PS I and PS II antennae sizes in the mutant were not accompanied by any major changes in quantum efficiencies of PS I and PS II in leaves at non-saturating light levels for CO2 assimilation. Although the chlorophyll deficiency resulted in an 11% decrease in light absorption by mutant leaves, their maximum quantum yield and light saturated rate of CO2 assimilation were similar to those of wildtype leaves. Consequently, the large and different decreases in the antennae of PS II and PS I in the mutant are not associated with any loss of light use efficiency in photosynthesis.
研究了一种由单个核基因突变引起的、叶绿素缺乏的豇豆花突变体的捕光和光合作用特性。突变体叶片的总叶绿素含量减少了 40%，与光系统 II（PS II）相关的捕光色素蛋白减少了 55%，与光系统 I（PS I）相关的捕光色素蛋白减少了 35%。与野生型亲本相比，突变体叶片的 PS I 和 PS II 含量没有差异。突变体中 PS I 和 PS II 天线的减少并没有伴随着 CO2 同化的非饱和光水平下叶片 PS I 和 PS II 量子效率的任何重大变化。尽管叶绿素缺乏导致突变体叶片的光吸收减少了 11%，但其最大量子产率和光饱和 CO2 同化速率与野生型叶片相似。因此，突变体中 PS II 和 PS I 天线的大量和不同减少与光合作用中光利用效率的任何损失无关。
