Effect of a Newly-Developed Nutrient Solution and Electrical Conductivity on Growth and Bioactive Compounds in Perilla frutescens var. crispa

Abstract

We evaluated the effect of a newly-developed nutrient solution of red perilla (NSP) with various electrical conductivity (EC) levels on plant growth, mineral content, and bioactive compounds. Four-week-old seedlings were grown in greenhouse nutrient solution as control (CT) (EC 1–3 dS m−1) or NSP (EC 1–6 dS m−1). NSP 1 dS m−1 induced better growth characteristics, whereas higher EC levels inhibited plant growth. Most of the macro-elements contents significantly decreased under NSP 6 dS m−1, whereas the micro-elements contents fluctuated according to EC levels. Total phenolic concentration in NSP was lower than that in CT, and total phenolic content was highest under NSP 1 dS m−1. Total anthocyanin and antioxidant concentrations and contents increased at lower EC levels. Rosmarinic and caffeic acids concentrations increased at higher EC levels, whereas there were no significant differences in these compound contents among the EC levels. No difference in perillaldehyde concentration was observed, whereas the content was higher at lower EC levels. Overall, these results suggest that NSP 1 dS m−1 is suitable for cultivating red perilla in plant factories.

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

“…Plants require large amounts of macronutrients to carry out cellular functions, K in one amongst these, and stands 3rd on the list of requirement and importance to plants [ 36 ]. Macronutrients play a key role in plant development and can be divided into two groups, primary macronutrients (P, K, and N) and secondary macronutrients (Ca, Mg, and S); among these nutrients, N, P, and K are the most crucial elements in plants [ 22 ]. K nutrition could optimize water use efficiency and photosynthesis [ 37 ].…”

“…Consistent with the present study results, previously, it was demonstrated that 6.5 ds m −1 EC reduced the leaf expansion and individual leaf area in tomato [ 47 ]. In a different study, treatment with nutrient solution at lower levels (1 and 2 dS m −1 ) had positive effects in the leaf area and number, whereas under higher nutrient solution (5 and 6 dS m −1 ) treatments a negative effect was observed in all growth characteristics of red perilla [ 22 ]. Similarly, treatment with EC 3 dS m −1 had a positive effect in the growth and development of red and green perilla, which may be due to the difference in nutrient solution formulas [ 48 ].…”

“…EC level is an important factor in nutrient solution and reflects the total content of macro—and microelements available for the plants [ 21 ]. High EC levels can inhibit the nutrient uptake by increasing osmotic pressure and salt stress, whereas low EC levels may lead to nutrient deficiencies and inhibition of growth and development of plants [ 22 ]. Salt stress can cause premature aging of the leaves and chloroplast and chlorophyll content reduction [ 23 ], which eventually leads to plant death [ 24 , 25 ].…”

Allelopathic Efficiency of Plant Extracts to Control Cyanobacteria in Hydroponic Culture

“…were sown in plug trays filled with fine perlite (GFC Co., Hongseong, Korea) and cultured under natural sunlight in a greenhouse. After 20 days since germination started, and when there were two pairs of true leaf appearance, seedlings of similar size were selected and transplanted into glass bottles containing 300 mL of Hoagland solution [27,28]. The electric conductivity of the solution was measured to 2.21 ± 0.1 mS cm −1 .…”

“…The mean values of EC exhibited 2.262 ± 0.01 and 2.195 ± 0.03 mS cm −1 on initial and harvest day, respectively. The EC values were included within a reasonable EC range for perilla growth [28]. In addition, the mean values of pH were 6.8 ± 0.02 and 7.1 ± 0.06 on initial and harvest day, respectively.…”