Gas exchange and leaf area of banana plants under salt stress inoculated with growth-promoting bacteria

Marlos A Bezerra,Ana J O Rodrigues,Cynthia M R Nogueira,Christiana De F B Da Silva,Alan B O De Sousa,Beatriz De A Araújo

doi:10.1590/1807-1929/agriambi.v25n11p779-786

Abstract

ABSTRACT Banana orchards in arid and semiarid regions require the use of irrigation. However, the presence of high concentration of salts in water can impair the development of plants, requiring the evaluation of new technologies to mitigate the effects of stress. The objective of this study was to evaluate gas exchange and leaf area in banana seedlings of the cultivar Prata Catarina inoculated with strains of Bacillus spp. under different electrical conductivities of irrigation water. The experiment was carried out in a greenhouse at Embrapa Tropical Agroindustry, Fortaleza, Ceará state, Brazil. The design used was in randomized blocks, in a 4 × 4 factorial scheme, with the first factor being the inoculation treatments: without any application; slow-release fertilizer; Strain 186 and Strain 109, and the second factor being the electrical conductivity of irrigation water (0.5; 1.5; 3.0; 4.5 dS m-1), in five blocks and each plot consisting of three plants. The electrical conductivity of irrigation water negatively influenced the gas exchange of banana cv. Prata Catarina in the vegetative stage, during the 89 days of cultivation. The Bacillus spp. strains 186 and 109 did not improve the gas exchange and leaf area of plants under salinity conditions.

Highlights

The Brazilian Northeast has the largest area cultivated with banana in the country, with 177,300 ha, and the second largest production, with 2.2 million tons (Agrianual, 2019; IBGE, 2020)
An alternative to attenuate salt stress in plants may be the use of growth-promoting bacteria (PGPB)
Knowing that salinity severely affects younger banana plants, the present study aimed to evaluate the use of Bacillus sp. strains to reduce the effects of irrigationwater salinity on the gas exchange of seedlings of ‘Prata Catarina’ banana

Summary

Introduction

The Brazilian Northeast has the largest area cultivated with banana in the country, with 177,300 ha, and the second largest production, with 2.2 million tons (Agrianual, 2019; IBGE, 2020). In 2020, the mean annual banana production in the Southeast and Northeast regions exceeded 2300 million tons for both regions, with thousand fruits produced per hectare in the Southeast region and more than thousand produced per hectare in the Northeast region (IBGE, 2020). A possible disadvantage of this technology is the fragility of the seedlings, which require an acclimatization phase. This phase is very sensitive and the use of water with high concentrations of salts, a common condition in the Brazilian Northeast region, can cause varying degrees of stress in plants and reduction of production potential (Larcher, 2004). An alternative to attenuate salt stress in plants may be the use of growth-promoting bacteria (PGPB)

Objectives

Methods

Results