Phosphite as an inductor of adaptive responses to stress and stimulator of better plant performance

Abstract

Phosphite (Phi) is emerging as a novel molecule that can be used as a biostimulant to enhance plant performance in limiting environments. In addition, Phi is effective against some pathogenic bacteria, oomycetes, fungi, and nematodes that significantly affect crop production and productivity. As a biostimulant, Phi may improve the yield and quality of a number of important crop species and can induce better performance of plants exposed to abiotic stress factors. In conventional agricultural systems, Phi cannot be used as a nutrient source and hence cannot substitute or complement inorganic phosphate (Pi) fertilizers. Instead, novel genetic engineering approaches are currently allowing its use as an alternative Pi fertilizer and herbicide, although it is not yet widely used on a commercial basis. This innovative biotechnology is addressing the challenges of Pi reserve depletion and multiple herbicide tolerance in weeds. In terms of biostimulation and induction of better plant performance, the beneficial effects of Phi on plant metabolism are more evident in conditions of Pi sufficiency. Additionally, Phi applications are more efficient when properly timed to match plant requirements, which in turn depend on the genotype of the crop plant used, type of soil and climate where plants are grown, cultural practices, as well as the dose, rate, and Phi source to be used. This chapter outlines the recent research advances on the effects of Phi as a potential biostimulator, pesticide, and a dual fertilizer and herbicide in agriculture and discusses potentialities and challenges of its use, especially those related to its utilization as an inductor of adaptive responses to stress in plants.