Nutrient Solution Strength Does Not Interact with the Daily Light Integral to Affect Hydroponic Cilantro, Dill, and Parsley Growth and Tissue Mineral Nutrient Concentrations

Abstract

Our objectives were to quantify the growth and tissue mineral nutrient concentrations of cilantro (Coriandrum sativum 'Santo'), dill (Anethum graveolens 'Fernleaf'), and parsley (Petroselinum crispum 'Giant of Italy') in response to nutrient solution electrical conductivity (EC) under low and high photosynthetic daily light integrals (DLI). Three-week old seedlings of cilantro, dill, and parsley were transplanted into nutrient-film technique hydroponic systems with one of five nutrient solution EC treatments (0.5, 1.0, 2.0, 3.0, or 4.0 dS·m −1 ) in greenhouses under a low (~7.0 mol·m −2 ·d −1 ) or high (~18.0 mol·m −2 ·d −1 ) DLI. The DLI, but not nutrient solution EC, affected culinary herb growth. For example, fresh mass increased by 21.0 (154%), 17.1 (241%), or 13.3 g (120%) for cilantro, dill, and parsley, respectively, for plants grown under high DLI compared to those grown under a low DLI; dry mass followed a similar trend. Tissue nutrient concentrations were generally affected by either DLI or EC. For those nutrients affected by DLI, concentrations increased with increasing DLI, except for potassium (K; all species) and manganese (Mn; dill). For those nutrients affected by EC, Ca and Mg decreased with increasing EC, while the remaining increased with increasing EC. When our tissue nutrient data are compared to recommended tissue concentrations, the vast majority of elements were either within or above recommended tissue ranges for cilantro, dill, and parsley. Our results demonstrate cilantro, dill, and parsley can be successfully grown across a range of EC, regardless of the light intensity of the growing environment.

Effects of Electrical Conductivity, pH, and Foliar Application of Calcium Chloride on Yield and Tipburn of Lactuca sativa Grown Using the Nutrient–Film Technique

“…Reduced macronutrients have contributed to reduced growth at EC levels, as reported previously in hydroponics lettuce (Fallovo et al, 2009;Samarakoon et al, 2019). In herbs (Ocimum spp., Coriandrum sativum, Anethum graveolens, and Petroselinum crispum) grown in NFT systems, yield was not influenced by EC changes between 0.5 to 4.0 mS • cm -1 (Currey et al, 2019;Walters and Currey, 2018). In those studies, EC adjustments were done every day or automatically, and the tank size for the nutrient solution was double compared with our study.…”

Historical, Current, and Future Perspectives for Controlled Environment Hydroponic Food Crop Production in the United States

“…chinensis) increased; however, plants were only irrigated three times per week, and the hydroponic production system type is unknown (Ding et al, 2018). Additionally, high-wire tomatoes grown with ECs ranging from 2.5 to 5.0 dS • m -1 irrigated daily and NFT-grown culinary herbs with ECs from 0.5 to 4.0 dS • m -1 and daily pH and EC adjustment had similar fresh weight among EC treatments (Currey et al, 2019;Walters and Currey, 2018;Wu and Kubota, 2008). The authors hypothesize that EC may not limit growth when adjusted continuously but may become a limiting factor when nutrient solutions are adjusted periodically in recirculating systems.…”

“…A more consistent trend is observed between crops regarding nutrient uptake. For example, as EC increased, N concentration increased in pakchoi (Ding et al, 2018) and culinary herbs (Currey et al, 2019;Walters and Currey, 2018) and lycopene, fructose, glucose, and total soluble solids increased in tomato (Wu and Kubota, 2008).…”

Morphological Responses of Viola Accessions to Nutrient Solution Application and Electrical Conductivity

“…Another study showed that greatest growth was recorded at N:K 40:30, which also had a positive effect of the flowering parameters of pansy [ 45 ]. Currey et al [ 46 ] demonstrated that cilantro, dill, and parsley can be grown successfully in different ranges of EC levels in hydroponic cultivation.…”