BIOSTIMULATION OF CHAYOTE [Sechium edule (Jacq.) Sw.] IN RESPONSE TO THE APPLICATION OF PHOSPHITE

Abstract

Phosphite (Phi; H₂PO₃^-) is considered a new biostimulant in horticulture, which can improve crop yield and quality, in addition to stimulating tolerance to environmental stress. In this study, the effect of the application to the roots and leaves of 0, 5, 10, 15, 20 and 25 μM Phi on plant height, leaf length, leaf width, stem diameter, root length, root volume, as well as on the concentrations of proteins, chlorophylls glycine betaine and proline was evaluated in chayote [Sechium edule (Jacq.) Sw.] var. virens levis. Treatments were applied weekly for four weeks. The experiments were carried out under greenhouse conditions in pots containing a mixture of peat and agricultural soil (1:1; v:v) as substrate. The treatments did not cause leaf damage, but the highest dose (25 μM Phi) negatively affected some growth traits. When applying 20 μM Phi, the root volume was higher, while with 5 μM Phi a higher stem dry biomass production was observed compared to the control. The 15-25 μM Phi range increased proline concentration. In general, the application of doses equal to or lower than 15 μM Phi improved some attributes of growth and metabolism, while doses higher than 15 μM Phi had some negative affects on those attributes. It is conclude that Phi may play a crucial role as an inorganic biostimulant in chayote cultivation, when applied properly.