Journal of Tianjin Agricultural University ›› 2026, Vol. 33 ›› Issue (3): 6-12.doi: 10.19640/j.cnki.jtau.2026.03.002

Previous Articles     Next Articles

Heterosis of photosynthetic production capacity in single-cross maize hybrids and their response to nitrogen fertilizer

Yang Jing1, Qu Yimin1, Zhang Zhongdong2, Yu Shaobo1,Corresponding Author, Zhang Lei1,Corresponding Author   

  1. 1. Department of Biology, Xinzhou Normal University, Xinzhou 034000, Shanxi Province, China;
    2. Institute of Maize Research, Shanxi Agricultural University, Xinzhou 034000, Shanxi Province, China
  • Received:2024-10-28 Online:2026-06-30 Published:2026-06-30

Abstract: The relationship between the heterosis of photosynthetic capacity and yield heterosis in drought-resistant maize is very close. Investigating the photosynthetic heterosis of maize is of great significance for the selection and breeding of high-efficiency varieties and high-yield and efficient cultivation. This study used typical drought-resistant maize varieties ‘Xianyu 335' and ‘Zhengdan 958' and their parents as experimental materials to explore the intrinsic relationship between the heterosis of photosynthetic production capacity indicators and yield heterosis in single-cross maize under two nitrogen supply levels. The results showed that at 0 kg/hm² nitrogen level, the SPAD, Pn, Gs, Ci, and Tr of drought-resistant maize leaves did not show heterosis compared to inbred lines, while yield exhibited a relatively low heterosis(51.89%). After nitrogen application, the heterosis of photosynthetic indicators such as SPAD, Pn, Gs, Ci, and Tr appeared(4.03%, 35.90%, 51.00%, 15.60%, and 30.20%), and the yield heterosis(94.34%)increased by 42.45% compared to the no-nitrogen treatment. Under the condition of 0 kg/hm2 nitrogen, the heterosis of yield mainly comes from crop dry matter accumulation and LAI, but the photosynthetic performance index of leaves does not have heterosis. After nitrogen application, the dry matter accumulation and LAI still have heterosis, and the photosynthetic production capacity of dry corn leaves shows obvious heterosis(especially Gs and Pn). The results show that nitrogen application can significantly improve the heterosis of photosynthetic capacity of leaves of dry-land maize single cross, and nitrogen application is the main reason for the significant improvement of heterosis of maize single cross yield.

Key words: maize, hybrids, photosynthetic characteristics, heterosis, physiological basis

CLC Number: