WATERCRESS AND CHINESE CABBAGE IN A HYDROPONIC SYSTEM USING GROUNDWATER

Raquele Mendes De Lira,Gerônimo Ferreira Da Silva,Hammady Ramalho E Soares,Ênio Farias De França E Silva,Pedro Róbinson Fernandes De Medeiros,Alexsandro Oliveira Da Silva

doi:10.1590/1983-21252019v32n420rc

Abstract

ABSTRACT Groundwater with high salt concentrations is common in the semiarid region of Brazil. It often makes them inappropriate to conventional agricultural production of vegetables. Therefore, the objective of this work was to evaluate watercress and Chinese cabbage crops under a nutrient film technique (NFT) hydroponic system using brackish groundwater. The experiment was carried out in the Poço do Boi region, in Ibimirim, Pernambuco, Brazil (8º32'15"S, 37º41'30"W, and altitude of 431 m). The treatments used were: public water (T1), calcium sulfate water (T2), magnesium chloride water S1 (T3), calcium chloride water (T4), sodium chloride water (T5), and magnesium chloride water S2 (T6). A completely randomized experimental design was used, with six treatments and four replications, totaling 24 plots for each crop. The fresh and dry shoot weights and rates of relative and absolute growths were analyzed. The different waters used affected negatively the growth and yield of the watercress and Chinese cabbage plants. The calcium chloride water was the most suitable for the watercress production. However, none of the groundwaters used could be recommended for production of Chinese cabbage. The lowest growth rates (5.88% to watercress and 0.75% to Chinese cabbage) of the fresh matter were found with the use of magnesium water.

Highlights

Water is a limiting factor for plant development in regions with low annual rainfall depths and high evapotranspiration, such as the semiarid region of Brazil; water scarcity in this region hinders agricultural production, causing economic and social losses that compromise the subsistence of the population (COSME et al, 2011).Groundwater is an alternative for water supply (LUNA et al, 2013; SILVA et al, 2014)
This can be attributed to the use of brackish water for the replenishing of the water lost by evapotranspiration and for preparation of the nutrient solution of each treatment, which caused an accumulation of salts in the solution as a function of the plant water consumption
Similar result was found by Lira et al (2015) who subjected Chinese cabbage to different salinity (NaCl) levels in the preparation and replenishing of the nutrient solution

Summary

Introduction

Water is a limiting factor for plant development in regions with low annual rainfall depths and high evapotranspiration, such as the semiarid region of Brazil; water scarcity in this region hinders agricultural production, causing economic and social losses that compromise the subsistence of the population (COSME et al, 2011).Groundwater is an alternative for water supply (LUNA et al, 2013; SILVA et al, 2014). Researches have evaluated the viability of using brackish water for crops in hydroponic systems (SOARES et al, 2007; SILVA, 2012; JESUS et al, 2015), since crops present higher salt tolerance when grown is this system than in conventional cultivation system. This is due to the greater and constant water availability in this system and to the little or no contribution of the matric potential to the total water potential, resulting in a greater absorption of water and nutrients by plants for the same amount of salts

Objectives

Methods

Results

Conclusion