%A WU Bing-Hui, WANG Gui-Ping, WANG Yu-Bin, LI Zhao-Hu, ZHANG Ming-Cai %T Regulation of ACC treatment on nitrogen supply response of maize seedlings with different genotypes %0 Journal Article %D 2021 %J Acta Agronomica Sinica %R 10.3724/SP.J.1006.2021.03047 %P 799-806 %V 47 %N 5 %U {https://zwxb.chinacrops.org/CN/abstract/article_7091.shtml} %8 2021-05-12 %X

Ethylene plays an important role in the growth and morphological formation of maize, while little research is involved in the regulatory effects of ethylene on the nitrogen absorption and accumulation in maize, which limits the application of ethylene in high yield and efficient cultivation of maize production. In this study, three maize varieties (Zhengdan 958, Ruifuer 1, and Demeiya 3) were used as experimental materials to study the response of maize varieties with different nitrogen absorption efficiency under different nitrogen levels condition. Combined with the addition of the precursor of ethylene synthesize 1-aminocyclopropane-1-carboxylic acid (ACC), the regulation effects of ethylene on nitrogen uptake of different genotypes were analyzed in maize. The results showed that nitrogen-sensitive varieties (Ruifuer 1 and Demeiya 3) had more obvious phenotype of nitrogen deficiency than Zhengdan 958 under low nitrogen condition, and were more sensitive to ACC treatment. Moreover, ACC treatment repressed the growth and dry matter accumulation in the shoot and root of maize plants. ACC treatment decreased the chlorophyll content of leaves under low nitrogen, reduced the accumulation of soluble protein in leaves, and promoted the premature aging of maize leaves. Among them, the contents of chlorophyll and soluble protein in Zhengdan 958 leaves with ACC treatment were significantly higher than those of Ruifuer 1 and Demeiya 3. Furthermore, low nitrogen treatment inhibited the expression of key enzymes (ZmACS7 and ZmACO15) in ethylene synthesis, while decreased the ethylene release rate. Thus, ACC treatment promoted the expression of ZmACS7 and ZmACO15 and enhanced ethylene release rate under low nitrogen treatments. Low nitrogen treatment inhibited the expression of ZmNRT2.1 in maize roots, but ACC treatment promoted the expression of ZmNRT2.1 in maize roots. In addition, the expression of ZmNRT2.1 in roots of Zhengdan 958 was significantly higher than those of Ruifuer 1 and Demeiya 3 under low nitrogen treatments. The results showed that ethylene regulated the uptake and distribution of nitrogen by regulating the key enzyme genes of ethylene synthesis and the expression of ZmNRT2.1 in maize which affected plants growth , and nitrogen-sensitive varieties were more sensitive to ethylene than green-holding variety.