Photosynthetic and yield responses of rotating planting strips and reducing nitrogen fertilizer application in maize-peanut intercropping in dry farming areas

Fei Han; Shuqing Guo; Song Wei; Ru Guo; Tie Cai; Peng Zhang; Zhikuan Jia; Sadam Hussain; Talha Javed; XiaoLi Chen; Xiaolong Ren; Mohammad Khalid Al-Sadoon; Piotr Stępień

doi:10.3389/fpls.2022.1014631

Photosynthetic and yield responses of rotating planting strips and reducing nitrogen fertilizer application in maize-peanut intercropping in dry farming areas

Front Plant Sci. 2022 Nov 16:13:1014631. doi: 10.3389/fpls.2022.1014631. eCollection 2022.

Authors

Fei Han^{1

2

3}, Shuqing Guo¹, Song Wei^{1

2}, Ru Guo^{1

2}, Tie Cai^{1

2

3}, Peng Zhang^{1

2

3}, Zhikuan Jia^{1

2

3}, Sadam Hussain^{1

2

3}, Talha Javed⁴, XiaoLi Chen^{1

2

3}, Xiaolong Ren^{1

2

3}, Mohammad Khalid Al-Sadoon⁵, Piotr Stępień⁶

Affiliations

¹ College of Agronomy, Northwest A&F University, Yangling, Shaanxi, China.
² Key Laboratory of Crop Physic-ecology and Tillage Science in Northwestern Loess Plateau, Ministry of Agriculture, Northwest A&F University, Yangling, Shaanxi, China.
³ State Key Lab of Soil Erosion and Dryland Farming on the Loess Plateau, Institute of Soil and Water Conservation, Northwest A&F University, Yangling, Shaanxi, China.
⁴ Department of Agronomy, University of Agriculture, Faisalabad, Pakistan.
⁵ Department of Zoology, College of Science, King Saud University, Riyadh, Saudi Arabia.
⁶ Wroclaw University of Environmental and Life Sciences, Institute of Soil Science, Plant Nutrition and Environmental Protection, Wroclaw, Poland.

Abstract

Improving cropping systems together with suitable agronomic management practices can maintain dry farming productivity and reduce water competition with low N inputs. The objective of the study was to determine the photosynthetic and yield responses of maize and peanut under six treatments: sole maize, sole peanut, maize-peanut intercropping, maize-peanut rotation-intercropping, 20% and 40% N reductions for maize in the maize-peanut rotation-intercropping. Maize-peanut intercropping had no land-use advantage. Intercropped peanut is limited in carboxylation rates and electron transport rate (ETR), leading to a decrease in hundred-grain weight (HGW) and an increase in blighted pods number per plant (N_BP). Intercropped peanut adapts to light stress by decreasing light saturation point (I_sat) and light compensation point (I_comp) and increasing the electron transport efficiency. Intercropped maize showed an increase in maximum photosynthetic rate (Pn_max) and I_comp due to a combination of improved intercellular CO₂ concentration, carboxylation rates, PSII photochemical quantum efficiency, and ETR. Compare to maize-peanut intercropping, maize-peanut rotation-intercropping alleviated the continuous crop barriers of intercropped border row peanut by improving carboxylation rates, electron transport efficiency and decreasing I_sat, thereby increasing its HGW and N_BP. More importantly, the land equivalent ratio of maize-peanut rotation-intercropping in the second and third planting years were 1.05 and 1.07, respectively, showing obvious land use advantages. A 20% N reduction for maize in maize-peanut rotation-intercropping does not affect photosynthetic character and yield for intercropped crops. However, a 40% N reduction decreased significantly the carboxylation rates, ETR, I_comp and Pn_max of intercropped maize, thereby reducing in a 14.83% HGW and 5.75% lower grain number per spike, and making land-use efficiency negative.

Keywords: N reducing; dry farming areas; light adaptation; maize-peanut intercropping; rotation of crop planting strip.