Horticulture Environment and Biotechnology 

About: Horticulture Environment and Biotechnology is an academic journal published by Springer Science+Business Media. The journal publishes majorly in the area(s): Shoot & Biology. It has an ISSN identifier of 2211-3452. Over the lifetime, 1841 publications have been published receiving 14625 citations.

Blue LED light enhances growth, phytochemical contents, and antioxidant enzyme activities of Rehmannia glutinosa cultured in vitro

Abstract: The objective of the current study is to determine the effect of light quality on enhancement of growth, phytochemicals, antioxidant potential, and antioxidant enzyme activities at in vitro cultures of Rehmannia glutinosa Libosch. In vitro-grown shoot tip explants were cultured on the plant growth regulator (PGR)-free Murashige and Skoog (MS) medium and cultured under a conventional cool white fluorescent light (control), blue light emitting diode (LED) light or red LED light. After four weeks, the growth traits along with total phenol content, total flavonoid content, free radical scavenging activities, and antioxidant enzyme activities were measured. Interestingly, the blue or red LED treatments showed a significant increase in growth parameters compared with the cool white florescent light. In addition, the LED treatments increased the total phenol and flavonoid levels in leaf and root extracts. Furthermore, data on the total antioxidant capacity, reducing power potential, and DPPH radical scavenging capacity also revealed the enhancement of antioxidant capacity under both blue and red LED treatments. Especially, the blue LED treatment significantly increased the antioxidant enzyme activities in both the leaf and root, followed by the red LED treatment. Modulation in the spectral quality particularly by the blue LED induced the antioxidant defense line and was directly correlated with the enhancement of phytochemicals. Therefore, the incorporation of blue or red LED light sources during in vitro propagation of R. glutinosa can be a beneficial way to increase the medicinal values of the plant.

Light intensity and photoperiod influence the growth and development of hydroponically grown leaf lettuce in a closed-type plant factory system

Abstract: Effect of light provided by various light intensities combined with different photoperiods on the growth and morphogenesis of lettuce (Lactuca sativa L.) ‘Hongyeom Jeockchukmyeon’ in a closed-type plant factory system were evaluated in this study. Four light intensity treatments, i.e., 200, 230, 260, and 290 μmol·m−2·s−1 PPFD, provided from light-emitting diodes (LEDs), with a combination of three different photoperiods 18/6 (1 cycle), 9/3 (2 cycles) or 6/2 (3 cycles) (light/dark) were used. The combination of 290-9/3 (light intensity-photoperiod) showed the highest plant height and fresh shoot weight, while plants grown at 290-18/6 exhibited the greatest root fresh weight, leaf dry weight, and longest root length. The greatest leaf width, maximum number of leaves, and greatest root dry weight were observed in the treatment combination of 290-6/2. Anthocyanin content was found to be highest in the 290-6/2 and lowest in the 200-6/2 treatment, whereas chlorophyll fluorescence was observed to be highest in the 260-6/2 and the lowest in the 290-9/3 treatment. Our data showed that providing a high light intensity of 290 μmol·m−2·s−1 PPFD with a shorter photoperiod of 6/2 (light/dark) resulted in good plant growth and development of lettuce, whereas growth at light intensities of 230 or 260 μmol·m−2·s−1 PPFD with longer photoperiods of 18/6 and 9/3 (light/dark) resulted in good growth as well as higher photosynthetic capacity.

Influence of silicon supplementation on the growth and tolerance to high temperature in Salvia splendens

Abstract: In this study, effects of silicon (Si) on the growth and activities of major antioxidant enzymes, such as superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX) and guaiacol peroxidase (GPX), and protein profile under high temperature stress were investigated. Salvia splendens ‘Vista Red’ and ‘Sizzler Red’ were grown in a glasshouse and potassium silicate (0 or 100 mg·L−1) was supplemented hydroponically. Overall important growth parameters, chlorophyll content, and biomass were significantly increased by Si application. In both cultivars, more Si deposition occurred in the root, followed by leaf and flower. In both normal and high temperature conditions, supplemented Si increased the activity of SOD, APX, and GPX, while it decreased the CAT activity. In the SDS-PAGE protein profile, three bands responding differentially to the Si treatment were observed. Especially in ‘Vista Red’ treated with Si, a protein band, approximately 46 kDa, was expressed strongly under the temperature stress. Results of this experiment showed that Si not only promoted the growth of salvia, but also played a vital role against temperature stress.

Optimizing levels of water and nitrogen applied through drip irrigation for yield, quality, and water productivity of processing tomato (Lycopersicon esculentum Mill.)

Abstract: The main goal of this study was to evaluate the effects of different levels of irrigation water and nitrogen on yield, quality, and water productivity of processing tomato grown in clay-loam soil. Three water levels of pan evaporation (Epan) replenishment applied via drip irrigation (1.00 × Epan, 0.75 × Epan, and 0.50 × Epan) and four N application rates with fertigation (0, 60, 120, and 180 kg N·ha−1) were tested in the sub-humid climate conditions of Turkey during the 2010 and 2011 growing seasons. The highest marketable yields were observed with full irrigation (1.00 × Epan) for each season. Decreasing irrigation rate generally improved dry matter, total soluble solids, total sugars, titratable acidity, lycopene and total carotene, and decreased fruit NO3-N content and fruit total protein content slightly. The highest water productivity was obtained with a moderate soil water deficit (0.75 × Epan). The 180 kg N·ha−1 fertilization rate produced the highest values for marketable yield, fruit size, total soluble solids yield, NO3-N, and total protein content. Increasing N rate also increased the values of fruit total sugars and titratable acidity. Increasing both irrigation and N levels increased the NO3-N and protein contents. The higher lycopene and total carotene values were obtained in the treatments of 60 and 120 kg N·ha−1. Increasing N supply improved the water productivity with the 3 irrigation application ratios. Considering the quantity and quality for the processing and water productivity, the 0.75 × Epan irrigation regime and a 120 or 180 kg·ha−1 nitrogen supply can considered optimal.

Silver nanoparticles and silver ions: Oxidative stress responses and toxicity in potato ( Solanum tuberosum L) grown in vitro

Abstract: Under in vitro conditions, we examined the effects of silver nanoparticles (AgNPs) and silver (Ag) ions on potato (Solanum tuberosum L.) in terms of silver accumulation, production of reactive oxygen species (ROS), oxidative stress responses, and antioxidative defense systems. At all concentrations (except at 2 mg•L-1), the amount of Ag in the shoots and roots of Ag ion-treated plantlets was significantly higher than in plantlets treated with AgNPs. In both treatments, total ROS and superoxide anions were increased at concentrations greater than 2 mg•L-1. Damage caused by oxidative stress, such as ion leakage and cell death, was significantly higher in plantlets treated with AgNPs than those treated with Ag ions. Significant increases in the activities of superoxide dismutase, catalase, ascorbate peroxidase, and glutathione reductase (GR),were found in both AgNP-treated, and Ag ion-treated plantlets compared to the control. However, in AgNP-treated plantlets, GR activity was significantly decreased at 20 mg•L-1. A significant reduction in glutathione (GSH), ascorbate (ASA), and the ratios of GSH to oxidized glutathione (GSSG) and ASA to oxidized ascorbate (DHA)were observed in plantlets treated with both AgNPs and Ag ions at concentrations higher than 2 mg•L-1. Moreover, a greater decrease in GSH and ASA contents was seen in plantlets treated with AgNPs compared to those treated with Ag ions. The present study indicates that both AgNPs and Ag ion treatments impose oxidative stress on potato plantlets under in vitro conditions. Furthermore, based on plantlets’ responses to oxidative damage, the observed alteration in the activities of radical scavenging enzymes and the depletion of GSH and ASA, AgNPs seem to have higher toxicity than the equivalent mass of Ag ions.