四甲基戊二酸对夏玉米光合生产特征的调控效应

为研究四甲基戊二酸(TGA)对夏玉米光合特征和产量的调控效应, 2018、2019年在中国农业科学院新乡试验基地开展大田试验,以中单909 (ZD909)和京农科728 (JNK728)为试验材料,设置5个TGA施用梯度(0、75、150、225和300 g hm~(–2))。结果表明,适宜剂量的TGA处理可提高玉米产量、延缓玉米生育期内功能叶的衰老速率,增强灌浆期的净光合速率,试验条件下TGA的最佳施用量为150 g hm~(–2)。在TGA最佳施用量下, ZD909和JNK728的产量相比对照2年平均分别增加8.7%和11.7%。2个品种玉米生育期内叶绿素含量、可溶性蛋白含量和光合势相比对照平均分别增加14.3%和19.7%、18.7%和22.7%、10.9%和16.9%;而叶片衰老速率相比对照平均降低了55.9%和56.5%;灌浆期的净光合速率相比对照平均分别增加44.0%和58.4%。相关性分析表明,玉米产量与生育期内叶片衰老速率呈显著负相关,而与灌浆期净光合速率呈显著正相关。综上, TGA处理能够提高叶片叶绿素和可溶性蛋白含量,延缓玉米叶片衰老速率,并提高了灌浆期净光合速率,进而实现玉米增产。

Effect of tetramethyl glutaric acid on summer maize photosynthesis characteristics

In this study, we explore the effect of tetramethyl glutaric acid (TGA) photosynthesis characteristics and yield in summer maize. Field experiments were conducted in Xinxiang experimental station of Chinese Academy of Agricultural Sciences in 2018 and 2019. Two widely planted maize cultivars were planted, and five TGA application gradients (0, 75, 150, 225, and 300 g hm^-2) were carried out. The results showed that the appropriate TGA treatment could increase maize yield, delay functional leaf senescence rate during the whole growth stage, and enhanced net rate during the grain-filling stage, respectively. The optimal TGA dosage was 150 g hm^-2, the yield of Zhongdan 909 (ZD909) and Jingnongke (JNK728) respectively increased by 8.7% and 11.7% compared to the control treatment in two experimental years under the optimal TGA treatment. Furthermore, chlorophyll content, soluble protein content and leaf area duration of ZD909 and JNK728 increased by 14.3% and 19.7%, 18.7% and 22.7%, 10.9% and 16.9%, respectively, in contrast, leaf senescence rate decreased by 55.9% and 56.5%, respectively during the experimental years. In addition, net photosynthetic increase by 44.0% and 58.4%, respectively, during the grain-filling stage. Correlation analysis indicated maize yield was significantly negatively correlated with leaf senescence rate during the whole growth period, and significantly positively correlated with net photosynthetic rate during grain-filling stage. In conclusion, suitable TGA treatment could delay leaf senescence rate by increasing leaf chlorophyll and soluble protein content, and improve ear leaf net photosynthetic rate during the reproductive growth stage, and ultimately increased maize yield.