Tag Archives: Lycopersicon esculentum

xxx S. Rakutko, A. Avotiņš, I. Alsina and K. Berzina
New assessment tool for artificial plant lighting: case of tomato (Lycopersicon Esculentum Mill.)
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New assessment tool for artificial plant lighting: case of tomato (Lycopersicon Esculentum Mill.)

S. Rakutko¹, A. Avotiņš², I. Alsina³ and K. Berzina²

¹Federal Scientific Agroengineering Center VIM, branch in Saint Petersburg, Tyarlevo, Pushkinsky distr., RU196625 St. Petersburg, Russia
²Riga Technical University, Faculty of Power and Electrical Engineering, Kalku street 1, LV-1658 Riga, Latvia
³Latvia University of Life Sciences and Technology, Faculty of Agriculture, Institute of Plant and Soil Science, Liela street 2, LV-3001 Jelgava, Latvia

Abstract:

Growing crops under artificial conditions need a very favourable environment, especially the spectral composition of radiation influencing the plant biometry greatly. The study objective was to find how to assess the closeness of real growing conditions to the optimal ones using a single coefficient, which would reflect several time dependencies of individual growth indicators. The plant growth friendliness factor (KG)was proposed for this purpose. Tomato transplants (Lycopersicon Esculentum Mill., ‘Polonaise F1’) were grown in a peat substrate under two lighting systems with different light quality.One system consisted of eight fluorescent lamps OSRAM L58W / 840 LUMILUX Cool White and eight lamps L58W / 77 FLUORA mounted on the standard frame, alternating the lamp types (Type I spectrum).In the other lighting system, the PCB Star LEDs with wavelengths of red 630 nm and far-red 735 nm were added(Type II spectrum). The irradiance level was maintained at 140 μmol m-2 s-1, the photoperiod was 16 h. The ratio of long-wave flux to the total flux KL was calculated for these lighting systems (0.37 rel.units for Type I spectrum and 0.50 rel.units for Type II spectrum) and KG factor was determined by the proposed formula. The value of KG was found to be twice as small for Type I spectrum than for Type II spectrum. The significant difference in biometric parameters of tomato transplants grown under Type I and Type II spectra was revealed. The plants grown in the environment characterized by higher KG, were higher; they had more significant wet mass and stem neck diameter.

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343–348 I. Alsina, L. Dubova, M. Duma, I. Erdberga, A. Avotiņš and S. Rakutko
Comparison of lycopene and β-carotene content in tomatoes determined with chemical and non-destructive methods
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Comparison of lycopene and β-carotene content in tomatoes determined with chemical and non-destructive methods

I. Alsina¹*, L. Dubova¹, M. Duma², I. Erdberga¹, A. Avotiņš³ and S. Rakutko⁴

¹Latvia University of Agriculture, Faculty of Agriculture, Institute of Plant and Soil Science, Liela street 2, LV-3001 Jelgava, Latvia
²Latvia University of Agriculture, Faculty of Food Technology, Department of Chemistry, Liela street 2, LV-3001 Jelgava, Latvia
³Riga Technical University, Faculty of Power and Electrical Engineering, Kalku street 1, LV-1658 Riga, Latvia
⁴Institute for Engineering and Environmental Problems in Agricultural Production, Tyarlevo, Pushkinsky distr., RU196625 St. Petersburg, Russia
*Correspondence: ina.alsina@llu.lv

Abstract:

Tomatoes are one of the most popular vegetables due of their wide use as food. Tomatoes are not only tasty fruit, but one of its benefits – high carotenoids content is well-known. Non-destructive analyses methods are used more and more in different industries. It is cheaper, faster and environmentally friendly way of analyse than traditional chemical methods. But these methods need references to the traditional ones. The aim of this study was to find the correlation between lycopene and β-carotene content in tomatoes determined with reflectance spectrometer and extraction of pigments. Content of two carotenoids (lycopene and β-carotene) was determined in 27 varieties of tomatoes. Red, pink, orange, yellow and brown fruits were included in experiment. Reflectance spectrums of tomatoes fruits were obtained with remote sensing portable spectroradiometer RS-3500 (Ltd.Spectral Evolution). Tetrahydrofuran was used for extraction of pigments. Absorption spectra of extract were obtained by spectrophotometer UV-Vis -1800 (Ltd. Shimadzu). Linear regression analyses were performed to correlate spectral data with lycopene and β-carotene concentrations measured by pigment extraction. The best reflectance region for lycopene spectral detection was 570 ± 5 nm, but for β-carotene 487 ± 5 nm. Reflectance indexes for both pigments were worked out. High linear correlation (R2 > 0.9) between spectral parameters and lycopene concentration was detected. Correlation between results obtained with methods used for β-carotene determination was lower and depended of colour of tomatoes fruits.

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712-718 A. Radzevičius, R. Karklelienė, P. Viškelis, Č. Bobinas,R. Bobinaitė and S. Sakalauskienė
Tomato (Lycopersicon esculentum Mill.) fruit quality and physiological parameters at different ripening stages of; Lithuanian cultivars
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Tomato (Lycopersicon esculentum Mill.) fruit quality and physiological parameters at different ripening stages of; Lithuanian cultivars

A. Radzevičius, R. Karklelienė, P. Viškelis, Č. Bobinas,R. Bobinaitė and S. Sakalauskienė

Lithuanian Institute of Horticulture. LT-54333, Babtai, Kauno 30, Kaunas distr., Lithuania;e-mail: a.radzevicius@lsdi.lt

Abstract:

Four cultivars (‘Neris’, ‘Svara’, ‘Vytėnų didieji’, ‘Jurgiai’) and one hybrid (‘Vaisa’) of tomato (Lycopersicon esculentum Mill.) were investigated at the Lithuanian Institute of Horticulture from 2007─2008.During this investigation fruit quality and physiological parameters were evaluated: thelycopene and β-carotene contents, colour indices (CIE L*a*) and hue angle (h°) with chroma (C) at four different fruit ripening stages (I stage – green, II stage – beginning of ripening, III – not fully ripened, IV – fully ripened)A significant increase in lycopene and β-carotene content at each successive ripeningstage of tomato fruit was recorded. Tomato fruit colour became darker and the ratio of red to green colour increased during the ripening process. Chroma value increased with a change of tomato colour from green to light red, and subsequently declined at the red fruit stage, but chroma of the hybrid ‘Vaisa’ increased at all ripening stages.External colour was expressed in terms of hue angle. All the analyzed tomato cultivarsdeveloped a similar colour when mature, with average hue angles generally being close to 40 degrees, but the cultivar ‘Neris’ had lower hue value (32 degrees).

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