Response of soybean to soil waterlogging associated with iron excess in the reproductive stage

Author(s)

Lapaz, Allan de Marcos ^[1] ; de Camargos, Liliane Santos ^[1] ; Pereira Yoshida, Camila Hatsu ^[2] ; Firmino, Ana Carolina ^[3] ; Monteiro de Figueiredo, Paulo Alexandre ^[3] ; Aguilar, Jailson Vieira ^[1] ; Nicolai, Artur Bernardeli ^[3] ; de Paiva, Wesller da Silva ^[1] ; Cruz, Victor Hugo ^[3] ; Tomaz, Rafael Simoes ^[3]

Affiliation

^[1] Sao Paulo State Univ UNESP, BR-15385000 Ilha Solteira, SP - Brazil

^[2] Univ Western Sao Paulo UNOESTE, BR-19067175 Presidente Prudente, SP - Brazil

^[3] Sao Paulo State Univ UNESP, BR-17900000 Dracena, SP - Brazil

• Document type: Journal article
• Source: PHYSIOLOGY AND MOLECULAR BIOLOGY OF PLANTS; v. 26, n. 8 JUL 2020.
• Web of Science Citations: 0

Abstract

Soil waterlogging is a common problem in some agricultural areas, including regions under soybean (Glycine max) cultivation. In waterlogged soils, soil O(2)depletion occurs due to aerobic microorganisms and plants, affecting the metabolic and physiological processes of plants after suffering anoxia in their root tissue. Another harmful factor in this situation is the exponential increase in the availability of iron (Fe) in the soil, which may result in absorption of excess Fe. The present study sought to evaluate the response mechanisms in soybean leaves `Agroeste 3680' by physiological and biochemical analyses associating them with the development of pods in non-waterlogged and waterlogged soil, combined with one moderate and two toxic levels of Fe. Gas exchange was strongly affected by soil waterlogging. Excess Fe without soil waterlogging reduced photosynthetic pigments, and potentiated this reduction when associated with soil waterlogging. Starch and ureide accumulation in the first newly expanded trifoliate leaves proved to be response mechanisms induced by soil waterlogging and excess Fe, since plants cultivated under soil non-waterlogged soil at 25 mg dm(-3)Fe showed lower contents when compared to stressed plants. Thus, starch and ureide accumulation could be considered efficient biomarkers of phytotoxicity caused by soil waterlogging and excess Fe in soybean plants. The reproductive development was abruptly interrupted by the imposition of stresses, leading to a loss of pod dry biomass, which was largely due to the substantial decrease in the net photosynthetic rate, as expressed by area (A), the blockage of carbohydrate transport to sink tissues and an increase of malondialdehyde (MDA). The negative effect on reproductive development was more pronounced under waterlogged soil. (AU)

• FAPESP's process: 18/17380-4 - Evaluation of soybean varieties physiological and agronomic traits under different iron concentrations and under ideal hydric conditions and waterlogging
• Grantee: Allan de Marcos Lapaz
• Support Opportunities: Scholarships in Brazil - Master