Solar Radiation Effects on Dry Matter Accumulations and Transfer in Maize

Yunshan Yang; Xiaoxia Guo; Guangzhou Liu; Wanmao Liu; Jun Xue; Bo Ming; Ruizhi Xie; Keru Wang; Peng Hou; Shaokun Li

doi:10.3389/fpls.2021.727134

Solar Radiation Effects on Dry Matter Accumulations and Transfer in Maize

Front Plant Sci. 2021 Sep 16:12:727134. doi: 10.3389/fpls.2021.727134. eCollection 2021.

Authors

Yunshan Yang^{1

2}, Xiaoxia Guo², Guangzhou Liu¹, Wanmao Liu², Jun Xue¹, Bo Ming¹, Ruizhi Xie¹, Keru Wang¹, Peng Hou¹, Shaokun Li^{1

2}

Affiliations

¹ Key Laboratory of Crop Physiology and Ecology, Ministry of Agriculture and Rural Affairs/Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing, China.
² The Key Laboratory of Oasis Eco-Agriculture, Xinjiang Production and Construction Corps/College of Agronomy, Shihezi University, Shihezi, China.

Abstract

Solar radiation is the energy source for crop growth, as well as for the processes of accumulation, distribution, and transfer of photosynthetic products that determine maize yield. Therefore, learning the effects of different solar radiation amounts on maize growth is especially important. The present study focused on the quantitative relationships between solar radiation amounts and dry matter accumulations and transfers in maize. Over two continuous years (2017 and 2018) of field experiments, maize hybrids XY335 and ZD958 were grown at densities of 4.5 × 10⁴ (D1), 7.5 × 10⁴ (D2), 9 × 10⁴ (D3), 10.5 × 10⁴ (D4), and 12 × 10⁴ (D5) plants/ha at Qitai Farm (89°34'E, 44°12'N), Xinjiang, China. Shading levels were 15% (S1), 30% (S2), and 50% (S3) of natural light and no shading (CK). The results showed that the yields of the commonly planted cultivars XY335 and ZD958 at S1, S2, and S3 (increasing shade treatments) were 7.3, 21.2, and 57.6% and 11.7, 31.0, and 61.8% lower than the control yields, respectively. Also, vegetative organ dry matter translocation (DMT) and its contribution to grain increased as shading levels increased under different densities. The dry matter assimilation amount after silking (AADMAS) increased as solar radiation and planting density increased. When solar radiation was <580.9 and 663.6 MJ/m², for XY335 and ZD958, respectively, the increase in the AADMAS was primarily related to solar radiation amounts; and when solar radiation was higher than those amounts for those hybrids, an increase in the AADMAS was primarily related to planting density. Photosynthate accumulation is a key determinant of maize yield, and the contributions of the vegetative organs to the grain did not compensate for the reduced yield caused by insufficient light. Between the two cultivars, XY335 showed a better resistance to weak light than ZD958 did. To help guarantee a high maize yield under weak light conditions, it is imperative to select cultivars that have great stay-green and photosynthetic efficiency characteristics.

Keywords: density; dry matter accumulation and translocation; leaf area duration; maize; photosynthates; solar radiation.