Improvement of the photosynthetic characteristics of transgenic wheat plants by transformation with the maize C 4 phosphoenolpyruvate carboxylase gene

With 7 figures and 2 tablesAbstract Attempts have been made to transform C 3 crops with C 4 genes to improve the photosynthetic rate of C 3 plants. In our study, a full‐length cDNA for phosphoenolpyruvate carboxylase gene ( pepc ) was isolated from Zea mays by PCR. The pepc gene was introduced into wheat plants ( Triticum aestivum ) by particle bombardment transformation. The integration, transcription and expression of the pepc gene were confirmed by Southern blot, RT‐PCR and Western blot analysis. Physiological studies showed that phosphoenolpyruvate carboxylase activity in the transgenic plants was 140% higher than that of the untransformed plants. The highest rate of photosynthesis in the transgenic plants was 31.95 μmol CO 2 /m 2 /s, which was 26% greater than the rate in untransformed plants. The light saturation point and carboxylation efficiency of pepc transgenic wheat were 20% and 22.57% higher, respectively, than those of untransformed wheat. As a result, the weight of seed per spike and thousand‐grain weight were 0.23 g and 1.21 g higher than those of untransformed wheat. Our research will facilitate the further study of the function of the pepc gene in wheat plants.