PRODUCTIVITY AND QUALITY EVALUATION OF TARRAGON AND THYME GROWN UNDER ARTIFICIAL LIGHT

The research aimed at evaluation of productivity and quality of tarragon and thyme medicinal material was carried out on hydroponic installations during 2019-2020. The objects under study were Monarkh and Gudvin tarragon varieties as well as Medok and Zmeyka thyme varieties. The plants were grown in mineral cotton substratum. Fertikea Hydro complex fertiliser with microelements and calcium nitrate were used. The growing conditions: ambient temperature +22…+25℃, solution temperature +20℃, ambient humidity 55…65%. Experiment regimens: growing under white LEDs (luminous flux 8000 lm, color temperature 4000 K, PPF 165 mkmol/s/m2) and color LEDs (combination of red, blue and white LEDs (32:16:32), luminous flux 6573 lm, PPF 143 mkmol/s/m2), for 16-hour light regimen. We found that thyme grown on a vertical hydroponic system increase its biomass 2.0…3.5 times compared to the conventional growing. The highest productivity of Zmeyka thyme variety is reached under white light, while for both the tarragon varieties and Medok thyme variety it is reached under coloured LEDs. Chlorophyll-a content in green biomass is a little higher under coloured LEDs for Zmeyka thyme variety and Gudvin tarragon variety, while the reverse trend is observed for Monarkh tarragon variety. All the varieties show higher chlorophyll-b content under coloured LEDs. Combined chlorophyll-a and chlorophyll-b content increases under coloured LEDs for the thyme varieties and Gudvin tarragon variety. Monarkh tarragon variety shows the highest combined chlorophyll content under white LEDs. Carotenoid concentration in Medok thyme variety and Monarkh tarragon variety is higher under white LEDs and it is higher under color LEDs for the rest of the varieties. Flavonoids in the studied varieties accumulate statistically better (1.5…3.0 times) under white LEDs

Physiological responses of resistant and susceptible pepper plants to exogenous proline application under Phytophthora capsici stress

Phytophthora capsici Leon. is the main pathogen that limits the production of peppers. In this study, the effects of 1 and 10 mM proline (Pro), prior to exposure of resistant (CM-334) and susceptible (SD-8) pepper seedlings to P. capsici, on some physiological parameters were investigated. A lower Pro concentration (1 mM) was found to be more effective than 10 mM Pro in increasing the stress tolerance of the CM-334 cultivar. Namely, in CM-334 cultivar, the highest chlorophyll a, chlorophyll b, carotenoid, glucose and fructose content and 1,1-diphenyl-2-picrylhydrazyl (DPPH) scavenging activity percentage were detected on the seventh day after application of 1 mM Pro + P. capsici, while the lowest malondialdehyde (MDA) amount was measured on the third day in the same treatment. The highest ferric reducing antioxidant power (FRAP) increase was determined on the seventh day in the 10 mM Pro + P. capsici application. The effects of the same Pro treatments on the SD-8 cultivar somewhat differed; the highest amounts of chlorophyll a, chlorophyll b, anthocyanins, fructose, total protein and endogenous Pro were detected on the seventh day in the 1 mM Pro + P. capsici application, while the lowest MDA amount was measured on the third day after the 10 mM Pro + P. capsici application, the highest DPPH % and FRAP values were detected on the seventh day with 10 mM Pro + P. capsici application. Although some differences were detected between the cultivars, Pro application against the P. capsici stress in general resulted in a positive effect on photosynthetic pigments, soluble carbohydrates and antioxidant capacity in pepper. The exogenous application of Pro helped the non-resistant cultivar to overcome the stress.

EDTA and nitric acid responses on nickel uptake, translocation factor and pigments on Spinacia oleracea L. replanted seedlings in hydroponic solution

The effects of Na2EDTA and HNO3 on Ni2+ uptake by Spinacia oleracea seedlings replanted inhydroponic culture in a greenhouse was investigated. Eight week old seedlings, were exposed to various doses of Ni2+ (0, 1000, 2000, and 4000 mg/L) as NiSO4, at (0, 500 and 3000 mg/L) Na2EDTA and ( 0, 500 and 3000 mg /L) HNO3 in different combinations. There was a substantial increase in nickel uptake in chelated treatments (p < 0.05) compared to unchelated treatments of same concentrations of Ni2+. So, chelation enhanced Ni2+ uptake in S. oleracea. During the exposure, antioxidant defense system helped the plant to protect itself from the damage. Due to increasing nickel uptake by the plant, the photosynthetic pigments (i.e chlorophyll a, chlorophyll b and Caretenoids) gradually declined. In this study, Spinacia oleracea Seedlings and contents of the photosynthetic pigments (chlorophyll a, chlorophyll b and Caretenoids) of both chelated and unchelated hydroponic treatments were investigated. Changes in photosynthetic pigments was significant (p < 0.05) with respect to addition of EDTA and HNO3 at different concentration to different concentrations of Ni2+ compared to unchelated treatments of same concentrations of Ni2+. The Ni2+ induced translocation factor was also determined which increased significantly (P < 0.05) with increasing Ni2+ concentrations.

Effect of Selenium Application and Growth Stage at Harvest on Hydrophilic and Lipophilic Antioxidants in Lamb’s Lettuce (Valerianella locusta L. Laterr.)

Lamb’s lettuce (Valerianella locusta L. Laterr.) is a leafy green vegetable that is rich in various biological active compounds and is widely used in ready-to-eat salads. The cultivation conditions and growth stage could affect the secondary metabolism in plants and thereby modify their food value. In the present study, the effect of selenium (Se) application in various concentrations (5.0, 10.0, and 20.0 µM) on the contents of Se, phenolic compounds, vitamin C, carotenoids, chlorophylls, and antioxidant activity of hydrophilic and lipophilic extracts of lamb’s lettuce harvested at three growth stages (38, 52, and 66 days after sowing (DAS)) was studied. Se application significantly increased the Se concentration in the shoots (up to 124.4 μg g−1 dry weight), as well as the contents of chlorogenic acid, total flavonoids, total phenolics, ascorbic acid, chlorophyll b, and the antioxidant activity of hydrophilic and lipophilic extracts. A higher content of phenolic compounds and higher antioxidant activity of hydrophilic extracts was observed at the first growth stage (38 DAS). On the contrary, higher contents of lipophilic compounds (chlorophyll a, chlorophyll b, lutein, β-carotene) and higher antioxidant activity of lipophilic extracts were found for shoots harvested at later stages (52 and 66 DAS).

Salt-Induced Damage Alleviation in Tanacetum Balsamita L. by Foliar Application of Dobogen Biofertilizer, Glucose and KNO3

The effects of NaCl salinity stress and foliar application of KNO3, glucose and Dobogen were tested on Tanacetum balsamita. The results showed the significant interaction effects of salinity and foliar sprays on chlorophyll a, K+, Na+, Mg2+, Fe2+, Zn2+, Mn2+ and Si content, K/Na ratio and total phenolic and flavonoid contents. The highest phenolic content was acquired with 100 mM salinity and foliar spray of Dobogen and glucose, 50 mM NaCl × KNO3 application and 50 mM salinity× nonfoliar application. The highest K/Na ratio was observed in control plants and controls × KNO3 and/or Dobogen application. The greatest Si content was recorded with controls × Dobogen and KNO3 applications and no saline × no foliar control plants. Malondialdehyde, flavonoid and proline contents as well as catalase activity were influenced by the independent effects of treatments. Chlorophyll b and superoxide dismutase were affected by salinity. Total soluble solids and Ca2+ were influenced by foliar applications. Malondialdehyde and proline were the highest at 150 mM salinity. Salinity adversely affected the physiological responses of costmary. However, foliar treatments partially ameliorated the salinity effect, and the results would be advisable to the extension section and pioneer farmers.

Pigments in flower stems of lisianthus under different photoselective shade nets

The lisianthus culture is demanded to produce cut flowers and pot vases, grown in a greenhouse using advanced techniques. The present study aimed to evaluate the pigments of different lisianthus cultivars in different photoselective shade nets. The cultivars Flare Deep Rose (pink), Echo Blue BL (purple) and Allemande White BI (white) were cultivated under light-diffusing polyethylene film cover and blue and red color photoselective nets with a shading capacity of 30%, in addition to the control treatment, without the use of the net. The results showed higher values of chlorophyll b and total in the red photoselective net, independent of the cultivar. Leaf colorimetry showed the most intense shade of green was from the cultivar Echo Blue BL. On the other hand, the control showed more intensity, with no significant difference in the leaf green intensity on the blue and red shade nets. In the petals, the cultivar Echo Blue BL showed a more intense blue shade in the red net, however low grade of anthocyanin than in the blue one. In the anthocyanin pigment, this cultivar had lower levels in the treatment of the red net. The results indicate that the use of photoselective shade nets in the culture of lisianthus changes the content of the pigments studied, in varying intensity, depending on the cultivar.

Antioxidant properties of pepper (Capsicum annuum L.) depending on its cultivar and fruit colouration

Due to its nutritional, health-promoting and taste-related values, new cultivars are introduced every year. The aim of the study was to assess the biological value of Polish and Bulgarian cultivars of pepper grown in moderate climate conditions and collected at different degrees of maturity. Ascorbic acid, carotenoids, polyphenols, chlorophyll a, chlorophyll b, total chlorophyll and antioxidant activity (DPPH) were determined in air-dried fruit. The investigation included five Polish cultivars: Roberta, Marta Polka, Etiuda, Trapez, and Cyklon and five Bulgarian cultivars: Bulgarski Ratung, Sivriya, Kurtovska Kapiya, Delikates, and Dzuliunska Shipka. Its design involved randomised sub-blocks, with three replications comprising nine plants each. The area of a single plot was 1.44 m²(1.2 m × 1.2 m). The study confirmed the strong antioxidant properties of pepper grown in the field, without cover, and under temperate climate conditions. The vegetable is rich in vitamin C, polyphenols, carotenoids, chlorophyll pigments, and shows high antioxidant activity. However, the biological value of pepper is cultivar-dependent and is also determined by the fruit colouration degree. The coloured fruits are richer in vitamin C and carotenoids than the green ones, and when matured, they have greater antioxidant capacity. Green fruits contain more chlorophyll a, chlorophyll b and total chlorophyll than the coloured ones. The fruits of cv. Etiuda were the richest in vitamin C, of cv. Sivriya in polyphenols, of cv. Dzuliunska Shipka in carotenoids, and of cv. Trapez in total chlorophyll. Cv. Sivriya showed the strongest antioxidant properties.

Assessment of the effect of heavy metal salts on the photosynthetic activity of aquatic plants

The status of the photosynthetic pigments in the aquatic plants Lemna minor L. and Elodea canadensis Michx. under the action of Ni2+, Co2+, Cu2+ and Pb2+ acetate in concentrations 5.00, 2.50, 1.25, 0.62, 0.31, 0.15, 0.07, and 0.03 mg/L was assessed by changes in the fluorescence intensity of chlorophyll a and b and their ratio. It was established that nickel acetate in original solutions in all the above concentrations caused an increase in the fluorescence intensity of chlorophylls a and b in L. minor in relation to the control while the lead salt suppressed it. Co2+ acetate inhibits the fluorescence of chlorophyll a with concentrations in the initial solutions of 0.03 to 0.15 and 2.50 mg/L and that of chlorophyll b at all concentrations, except 0.62, 1.25 and 2.50 mg/L. For E. canadensis it was found that the salts of all metals at all concentrations caused a reduction of the fluorescence intensity of chlorophyll a relative to the control and increased it in the case of chlorophyll b. The exception is the effect of copper and lead acetates with a concentration of 1.25 mg/L, when the fluorescence intensity of chlorophyll b is maintained at the control level. The presence of Ni2+, Co2+, Cu2+, and Pb2+ acetates in all concentrations in the culture medium influences the quantitative and qualitative characteristics of chlorophyll a and b, which indicates a violation of the photosynthesis process. Our data on the change in the chlorophyll a / b ratio leads to a conclusion about degradation of chlorophyll a relative to chlorophyll b after the effect of heavy metals.

Interactive Impact of Biochar and Arbuscular Mycorrhizal on Root Morphology, Physiological Properties of Fenugreek (Trigonella foenum-graecum L.) and Soil Enzymatic Activities

Arbuscular mycorrhizal fungi (AMF) inoculation and biochar amendment has been reported to improve the growth of several crop plant; however, their role in stress amelioration individually as well as in combination has not been worked out. Limited information is available about the synergistic use of biochar and Arbuscular Mycorrhizal Fungi (AMF). Here, we investigated the synergistic effect of biochar and AMF on plant development, root architecture, the physiological performance of fenugreek (Trigonella foenum-graecum), and soil enzymatic activities. Biochar and AMF were shown to have a considerable effect on plant height, according to the data (53.3 and 66.6%, respectively), leaf number (22.5 and 45.1%), total root length (19.8 and 40.1%), root volume (32.1 and 71.4%), chlorophyll a content (26.0 and 17.8%), chlorophyll b content (50.0 and 28.9%), total chlorophyll content (30.0 and 18.1%), and carotenoid content (60.0 and 48.0%) over the control treatment. There was a considerable increase in plant height when biochar and AMF were combined together by 80.9%, total root length by 68.9%, projected area by 48.7%, root surface area by 34.4%, root volume by 78.5%, chlorophyll a content by 34.2%, chlorophyll b content by 68.4%, total chlorophyll content by 44.5%, and carotenoid content by 84.0% compared to the control. Our results recommend that the combination of biochar and AMF is advantageous in fenugreek growth, microbial biomass, and soil enzyme activities.

Paper Chromatographic Separation of Plant Pigments a New Approach by using Akshya-Swagatika Solvent and Mobile Chromatogram Detection System (MCDS)

Chromatography is a term that refers to a group of laboratory techniques for separating mixtures. Chromatography works on the premise of solute partitioning between two phases or solvents. The technique of paper chromatography is commonly used to separate plant pigments based on their molecular weight. Plant pigments include chlorophyll-b, chlorophyll-a, carotenoid, and xanthophyll, which all have various molecular weights, colours, and absorption maxima. In this study, an attempt was made to see how a new solvent (Akshya-Swagatika solvent) can be used to separate plant pigments using paper chromatography, as well as a new detection method developed by us known as Mobile chromatogram detection system (MCDS) that can be used for compound identification and photographing. As shown in the table and photograph, pigments are separated by molecular weight and band colour, with carotenoid having the highest RF value and chlorophyll-b having the lowest. It was obvious that the Akshya-Swagatika solution could be used to separate plant pigments in paper chromatography. Photograph taken with a mobile chromatogram detection system that is much clearer than normal one. In developing countries, both solvent and detection systems are useful in explaining paper chromatography in a cost-effective manner. The MCDS detection system is cost-effective fast method which replaces traditional sophisticated detection procedures.