Characterization of two Peruvian maize landraces differing in boron toxicity tolerance

Plant Physiol Biochem. 2022 Aug 15:185:167-177. doi: 10.1016/j.plaphy.2022.06.003. Epub 2022 Jun 6.

Abstract

Boron (B) toxicity is a major agricultural problem that causes a considerable decrease in crop yield and quality. The soil in arid and semi-arid areas is often subjected to excessive B content. Southwestern Perú (department of Tacna) is characterized by high B levels in its agricultural land and irrigation water. This work analyzes the response of two local maize (Zea mays) landraces (Pachía and Sama) from Tacna to B toxicity. Both landraces were, therefore, grown in hydroponic media under control and B toxicity conditions, and after 10 days, seedlings were harvested and B content, B-transporter gene expressions, and several morphological and physiological parameters were determined. The leaf and root soluble B content was lower in Sama than in Pachía when both landraces were subjected to high B concentrations, which could be explained by its higher expression levels of B-efflux transporters. The capacity of Sama to maintain reduced levels of soluble B in its leaves and roots led to decreased leaf damage and higher photosynthetic and growth parameters under B toxicity conditions. These results support the proposal that Sama would perform better than Pachía under excessive B conditions, thus making it a more suitable landrace to be used in soils with toxic levels of B.

Keywords: Aquaporins; Boron toxicity; Boron transporters; Photosynthesis; Zea mays.

MeSH terms

  • Boron* / metabolism
  • Boron* / toxicity
  • Peru
  • Photosynthesis
  • Plant Leaves / metabolism
  • Plant Roots / metabolism
  • Soil
  • Zea mays* / metabolism

Substances

  • Soil
  • Boron