Stress index, water potentials and leaf succulence in cauliflower cultivated hydroponically with brackish water

Abstract

The tolerance of crops to salinity is greater in hydroponic systems due to the low contribution of the matric potential to the total potential of the water. The objective of this study was to evaluate the use of brackish water, to prepare the nutrient solution and replace the evapotranspired volume, and rates of application of this solution on the water stress index, water potential, leaf succulence and water consumption of cauliflower cv. ‘Piracicaba Precoce’. The experimental design was completely randomized in a 6 x 2 factorial scheme, with six salinity levels used to prepare the nutrient solutions (0.2, 1.5, 2.5, 3.5, 4.5 and 5.5 dS m-1) and two application rates of these solutions (1.5 and 2.5 L min-1), with four replicates. Water stress index (WSI), water and osmotic leaf potentials, leaf succulence (LS) and water consumption were analyzed. The increase in water salinity reduced LS and increased WSI. Water salinity reduced the water and osmotic leaf potentials and water consumption of the crop; however, the effects were more pronounced at the rate of 2.5 L min-1. Application rate of 2.5 L min-1 led to the highest WSI and lowest LS.

Water yield and consumption of cauliflower plants grown in a hydroponic system using brackish waters and different flow rates

“…Similar results of water consumption were found by Cruz et al (2018) for cauliflower crops grown in NFT hydroponic system with different salinity levels; and by Soares et al (2010) and Paulus et al (2012) when evaluating the use of brackish waters in hydroponic lettuce crops.…”

“…Regarding the flow rates used, the best results were found for the lowest flow rate (1.5 L min -1 ); it was probably due to the greater water stress of plants in treatments with the highest flow rate, caused by the higher flow of salts in the rhizosphere of plants (Cruz et al, 2018).…”

The Assessment and the Within-Plant Variation of the Morpho-Physiological Traits and VOCs Profile in Endemic and Rare Salvia ceratophylloides Ard. (Lamiaceae)

“…Through these parameters, we also calculated the leaf mass per area (LMA, g LDW cm −2 LA), strongly related to photosynthetic rate [ 67 ], growth rate [ 68 ] and decomposition rate [ 69 ]; the leaf dry content (LDC, g dry weight/g fresh weight), strongly related with relative growth rate [ 70 ], flammability [ 71 ], and post-fire regeneration strategy [ 72 ]; and the leaf water content or leaf succulence (LWC, g H 2 O/cm 2 leaf area], directly correlated with the plant responses to abiotic stresses [ 73 ].…”

Salinity and flow rates of nutrient solution on cauliflower biometrics in NFT hydroponic system

“…The feasibility of using brackish waters to grow different leafy vegetables, especially in the context of hydroponic cultivation, is related to the absence of action of the matric potential, which has been widely proven by several studies (Soares et al, 2015;Cruz et al, 2018;Lira et al, 2018).…”