Characterization and expression patterns of key C4photosynthetic pathway genes in bread wheat (Triticum aestivum L.) under field conditions.
Wheat is a C3plant with relatively low photosynthetic efficiency and is a potential target for C4photosynthetic pathway engineering. Here we reported the characterization of four key C4pathway genes and assessed their expression patterns and enzymatic activities at three growth stages in flag leaves of 59 bread wheat genotypes. The C4-like genes homologous to PEPC, NADP-ME, MDH, and PPDK in maize were identified in the A, B, and D sub-genomes of bread wheat, located on the long arms of chromosomes 3 and 5 (TaPEPC), short arms of chromosomes 1 and 3 (TaNADP-ME), long arms of chromosomes 1 and 7 (TaMDH), and long arms of chromosome 1 (TaPPDK), respectively. All the four C4-like genes were expressed in the flag leaves at the three growth stages with considerable variations among the 59 bread wheat genotypes. Significant differences were observed between the photosynthesis rates (A) of wheat genotypes with higher expressions of TaPEPC_5, TaNADP-ME_1, and TaMDH_7 at heading and middle grain-filling stages and those with intermediate and low expressions. Our results also indicated that the four C4enzymes showed activity in the flag leaves and were obviously different among the 59 wheat genotypes. The activities of PEPcase and PPDK decreased at anthesis and slightly increased at grain-filling stage, while NADP-ME and MDH exhibited a decreasing trend at the three stages. The results of the current study could be very valuable and useful for wheat researchers in improving photosynthetic capacity of wheat.
State Key Laboratory of Crop Stress Biology for Arid Areas, College of Agronomy, Northwest A&F University, Yangling, Shaanxi, 712100, China.
Daoura Goudia
DG
Bachir
State Key Laboratory of Crop Stress Biology for Arid Areas, College of Agronomy, Northwest A&F University, Yangling, Shaanxi, 712100, China; NIFA, PO BOX 446, Tarnab, Peshawar, KP, Pakistan.
Iqbal
I
Saeed
State Key Laboratory of Crop Stress Biology for Arid Areas, College of Agronomy, Northwest A&F University, Yangling, Shaanxi, 712100, China.
Quanhao
Q
Song
State Key Laboratory of Crop Stress Biology for Arid Areas, College of Agronomy, Northwest A&F University, Yangling, Shaanxi, 712100, China.
Tay Zar
TZ
Linn
State Key Laboratory of Crop Stress Biology for Arid Areas, College of Agronomy, Northwest A&F University, Yangling, Shaanxi, 712100, China.
Liang
L
Chen
State Key Laboratory of Crop Stress Biology for Arid Areas, College of Agronomy, Northwest A&F University, Yangling, Shaanxi, 712100, China; Institute of Water Saving Agriculture in Arid Regions of China, Northwest A&F University, Yangling, Shaanxi, 712100, China. Electronic address: huyingang@nwsuaf.edu.cn.
Yin-Gang
YG
Hu
D032461:Chromosomes, Plant / Q000235:genetics; D018506:Gene Expression Regulation, Plant / Q000235:genetics / Q000502:physiology; D005838:Genotype; D010788:Photosynthesis / Q000235:genetics / Q000502:physiology*; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism; D015398:Signal Transduction / Q000235:genetics / Q000502:physiology; D014908:Triticum / Q000235:genetics / Q000378:metabolism* / Q000502:physiology*
D010940:Plant Proteins
C(4) enzyme activity; C(4) pathway; Gene expression; Photosynthetic efficiency; Wheat