Exogenous DCPTA Treatment Increases Mung Bean Yield by Improving Carbon Metabolism Pathway and Up-Regulating Photosynthetic Capacity and Antioxidants

Yuling Gao; Xiaolin Zhang; Xin Wang; Qi Zhang; Huarong Tang; Tian Qiu; HuiLai Zhang; Bingxin Zhao; Hao Wang; Xilong Liang; Yongxia Guo

doi:10.3389/fpls.2022.796694

Exogenous DCPTA Treatment Increases Mung Bean Yield by Improving Carbon Metabolism Pathway and Up-Regulating Photosynthetic Capacity and Antioxidants

Front Plant Sci. 2022 Apr 12:13:796694. doi: 10.3389/fpls.2022.796694. eCollection 2022.

Authors

Yuling Gao^{1

2

3

4}, Xiaolin Zhang⁵, Xin Wang^{1

2}, Qi Zhang^{1

2}, Huarong Tang^{1

2}, Tian Qiu^{1

2}, HuiLai Zhang^{1

2}, Bingxin Zhao^{1

2}, Hao Wang^{1

2}, Xilong Liang^{1

6}, Yongxia Guo^{1

2

3

4}

Affiliations

¹ College of Agriculture, Heilongjiang Bayi Agricultural University, Daqing, China.
² National Coarse Cereals Engineering Research Center, Daqing, China.
³ Heilongjiang Provincial Key Laboratory of Crop Pest Interaction Biology and Ecological Control, Daqing, China.
⁴ Heilongjiang Province Cultivating Collaborative Innovation Center for The Beidahuang Modern Agricultural Industry Technology, Daqing, China.
⁵ Dalian Customs Technology Center, Dalian, China.
⁶ Heilongjiang Plant Growth Regulator Engineering Technology Research Center, Daqing, China.

Abstract

Mung bean is characterized by having a good edible and medicinal value, while its flowers and pods have low production. Being a tertiary amine, DCPTA [2-(3,4-dichlorophenoxy) triethylamine] substantially regulates the growth and development of crops, maintaining production. Yet it is still limited in terms of the regulation of DCPTA on growth and development, including the yield and sugar metabolism of mung bean. In this study, DCPTA was sprayed at the beginning of mung flowering through a two-season cultivation, to assess its effects on the yield, leaf area per plant, plant height, seed setting rate, photosynthesis, chlorophyll content, and endogenous protective enzymes. Experimental results illustrated that relative to the control (CK), the DCPTA application significantly (p < 0.05) improved the yield of Bailv 11 mung bean, which rose to 6.9% in 2020 and 7.8% in 2021, respectively. This effect positively corresponded to a significant (p<0.05) increase in the number of pods and grains per plant and pod setting rate, but a non-significant difference in 1,000-grain weight. DCPA application also increased the area and fresh weight of leaf, mung height, and its organ dry weight (i.e., leaf, branch, and stem). During plant growth over DCPTA application, the increased activities of SOD, POD, and CAT improved the net photosynthetic rate, stomatal conductance, and transpiration. In addition, transcriptome sequencing further demonstrated that DCPTA treatment significantly (p < 0.05) up-regulated the sucrose synthase, invertase, and fructose kinase in all organs (i.e., leaves, pod skins, and grains) of the plant. In particular, this effect was much greater in the sucrose synthesis (i.e., sucrose content) in leaves. Our study, therefore, concludes that DCPTA application promotes the yield of mung bean via likely enhancing its photosynthetic capacity and sucrose synthase, fructokinase, and beta-fructofuranosidase expression regulation.

Keywords: DCPTA; carbon metabolism; exogenous; growth and development; mung bean; regulation; yield.