Pigment Complex Research Articles

Influence of the Systematic Position at the Family Level on the Leaf Functional Traits of Steppe Plants

The significance of the systematic position for the traits of a leaf, mesophyll, chloroplasts, and pigment complex in steppe plants has been examined for three families (Asteraceae, Poaceae, and Rosaceae) from different geographical regions of Russia and Mongolia. The species belonging to a particular family affects, first of all, the parameters of the whole leaf–its thickness and density–as well as the size and number of mesophyll cells. In contrast, mesophyll parameters and pigment content independent of the taxon, and both reflect the convergent response of plants belonging to different taxa to climate.

Reaction of pigment complex in meadow clover leaves to weather conditions and macronutrients

In the field studies of 2018…2019, the influence of macronutrients and weather conditions on pigment complex of leaves of meadow clover (Trifolium pratense L.) Dymkovsky variety was assessed. The study was carried out in grainfallow-grass crop rotation in the conditions of Kirov region. Leaf samples (fully developed second or third leaf from above) were taken in the flowering phase, and the chlorophyll and carotenoids content were measured spectrophotometrically under laboratory conditions. It has been found that the content of pigments in the leaves of meadow clover depended mostly on weather conditions of the year of cultivation. The concentration of green pigments (Chl a+b) in clover leaves was in the range of 15.34...19.05 in the conditions of warmer and dry 2018 and 11.47...14.10 mg/g dry matter in colder and humid year of 2019. Chl a accounted for 9.64...11.36 and 6.67...7.98 mg/g (2018 and 2019, respectively). Colder conditions promoted an increase in the ratio of Chl a associated with light-harvesting complexes (from 69…78 up to 89…96 %). Weight content of carotenoids was 2.69...3.12 and 1.52…1.88 mg/g in 2018 and 2019, respectively, and correlated with the content of a total chlorophyll (r = 0.53…0.82). The weight ratio of chlorophylls a/b (1.54... 1.75 in 2018 and 1.18... 1.47 in 2019) indicates a lack of insolation in the conditions of mutually shading of leaves of the created phytocenosis. However, the weight ratio of the sum of chlorophylls to carotenoids (5.7... 6.7 in 2018 and 6.86... 9.65 in 2019) suggests that this abiotic factor has not led to disorders in the structure of the photosynthetic leaf apparatus. Weather conditions considerably modified influence of fertilizers on pigment synthesis: in 2018, nitrogen fertilizers reduced the content of chlorophylls by 11…22 %, full mineral fertilizer on acid soil background led to decrease in the content of pigments by 6.7…11.7 %. In colder conditions of 2019 nitrogen fertilizers did not influence the content of pigments, full mineral fertilizer increased the content of Chl a by 14.1…17.8 %, carotinoids – by 18.2…25.4 %. In the conditions of 2019 the content of Chl a significantly depended on nitrogen content in leaves (r = 0.52…0.92) and correlated with phosphorus level in the soil: for Chl a – r = 0.74 and 0.54, for Chl b r = 0.73 and 0.75 (acid soil background and soil background with lime application, respectively).

The pigment complex and photosynthetic activity in the annual cycle of Polytrichum commune in the forest belt of the Khibiny Mountains on the Kola Peninsula of Russia

This paper presents data on the content and ratio of pigments, photosynthesis rate, and assimilation number throughout the annual cycle of Polytrichum commune in the forest belt of the Khibiny Mountains. It is shown that the activity of the pigment complex in the photosynthetic organs of P. commune is preserved and maintained over 2 years. The highest content of plastid pigments in this year’s shoots was recorded in fall, in the past year’s shoots in the summer. In winter, the content of chlorophylls in the photosynthetic organs of this year’s shoots decreased in 1.5 times relative to the summer maximum, and carotenoids - in 1.4 times. In the past year’s shoots, no significant changes in the content of the pigments were noted. During the active vegetation period, the photosynthetic intensity in this year’s shoots is in 1.5 times as high as that in the past year’s shoots. At the end of the growing season in the past year’s shoots the value of LHC (76%) due to their immersion deep into the moss clumps and shading them with this year’s shoots. Chlorophyll’s efficiency (assimilation number) in P. commune shoots of different ages in early spring (April) is in 2 times as high as that in fall (October).

The content of photosynthetic pigments in the leaves of Chrysanthemum×hortorum Bailey

The article presents data on the content of the main photosynthetic pigments in the leaves of various varieties of Chrysanthemum×hortorum, depending on the methods of cultivation. The efficiency of the photosynthetic apparatus is one of the most important parameter of the adaptive potential of plants in limiting environmental conditions. It’s linked with the peculiarities of the development and functioning of the pigment complex. The purpose of the work is to study the features of the content of photosynthetic pigments in the leaves of various Chrysanthemum×morifolium varieties to expand the assortment in the humid subtropics of Russia. The studies were conducted on model varieties of large-flowered (‘Sevan’ control, ‘Gilbert Leigh Purple’, ‘Gagarin’) and small-color chrysanthemums (‘Golden Niva’ control, ‘Tigerrag’, ‘Vesuvio’, ‘Dante’) cultivated in open and closed ground. It was found that relative humidity and illumination are higher in open ground throughout the year (average annual values in open ground are 65.4 % and 28 563 lx, in closed ground 61.8 % and 18 763 lx), while the temperature regime is higher in closed ground (average values in open and closed ground +18.6 °C and +20.8 °C, respectively). This favorably affects the preservation of the roots of chrysanthemum in winter when grown indoors in an unregulated microclimate (average temperature in the winter months in the open ground is +9.1 °C, in the closed +11.0 °C), but it negatively affects vegetative plants in the summer period (average temperature indicators in open and closed ground are +26.8 °С and +28.8 °С, respectively). The content of photosynthetic pigments in the leaves of Chrysanthemum×hortorum was studied in the period of the budding and flowering vegetation 2018-2019. Varietal differences were noted in the quantitative composition of pigments and their ratio, as well as differences depending on growing conditions in open ground and in protected ground (in glass greenhouses under solar heating).

Assessment of the pigment complex of some woody introducers of the family Rosaceae Juss. in a culture condition

The article presents the results of a study of the adaptation mechanisms of wood introducers of the family Rosaceae Juss. It was shown that a high content of photosynthetic pigments Nbi, Chl, Flv falls on the period of flowering and fruit ripening in plants. Pigment composition of leaves Padus maakii and Sorbaria sorbifolia indicates their high physiological status and adaptability in culture conditions.

Seasonal Dynamics of the Chlorophyll and Carotenoid Content in the Leaves of Steppe and Forest Plants on Species and Community Level

The content of chlorophylls (Сhl) a and b and carotenoids (Сar) during the growing season was studied in the leaves of 31 species of steppe and forest plants. In contrast to forest plants, steppe plants possessed less chlorophylls and carotenoids per leaf mass (2 and 1.5 times, respectively), a low Сhl/Сar ratio, a greater (1.5 times) content of carotenoids per leaf area, and a high Сhl a/b ratio. In spite of the low chlorophyll content per leaf mass in steppe plants, their content per leaf area was similar to forest species (3–4 mg/dm2) owing to their thicker and denser leaves. This suggests that the plants of steppe and forest communities have the same potential ability to intercept solar energy in this locality. In the period of active vegetation (mid-June -early August), parameters of the pigment complex were stable both in steppe and forest communities. However, steppe plants demonstrated the modified in content of Car and Сhl b, as well as Сhl/Сar and Chl a/b ratios, in the beginning and at the end of the season that indicated a reorganization of the light-harvesting complex. Intraspecific variation of parameters during the season was two or three times lower than interspecific. High interspecific variation in forest plants were achieved due to the presence of species with thick long-lived leaves. It was concluded that the chlorophyll content per leaf area reflects the adaptation of plants to climatic conditions of the geographic region, whereas pigment contents per leaf mass shows adaptation to local irradiation in plant community (forest or steppe).

Impact of mineral fertilizers, growth stimulators, pH regulators, vitamins and pigment supplements on the vitality of entomopathogenic nematodes of Steinernematidae and Heterorhabditidae families

Parasites of agricultural crops cause significant losses of quality and decrease in the profitability of agricultural production. Complex measures against pests are aimed both at termination of parasites and prevention of repeated infection of plants. One of the most progressive ways of protecting plants against harmful insects is the use of entomopathogenic nematodes. This method is most expedient in the conditions of organic arable farming. The results of our study reveal the impact of the fertilizers in various concentrations on the vitality of nematode larvae (L3) of four species (Steinernema feltiae, S. kraussei, S. carpocapsae and Heterorhabditis bacteriophora) and the possibility of their combined application for the treatment of plants. Mineral fertilizers and stimulators of growth of plants in 1% concentration insignificantly reduced the vitality of larvae, allowing them to be applied at the same time. We determined the tolerance of invasive larvae to pH for S. carpocapsae equaling рН = 0.9–13.4; optimum values of рН without reliable increase in the mortality during 24 h – рН = 1.3–12.8. Increase in the vitality of larvae (L3) of entomopathogenic nematodes was studied. The survivability of the cultures of larvae increased during the use of solutions of vitamins С, В1, В6, В12. We determined the influence of 21 pigment colourings on larvae (L3), the lowest effect on the vitality of nematode larvae was exerted by pigment bases Abrikos (7.0–10.8% mortality during 24 h), Zolotoi Pesok (6.0–11.8%), Pudra Ananasa (7.7–13.4%), and complex DMAE (7.6–17.4%). The results we obtained allow development of recommendations for agriculturalists for combined use of entomopathogenic nematodes with various substances and also improving the vitality of invasive nematodes.

Time-dependent enhancement of fluorescence from Rhodobacter capsulatus SB1003 and its critical dependence on concentration temperature and static magnetic field.

Continuous exposure of 395 nm light increases the fluorescence emission intensity of photosynthetic purple non-sulphur bacteria, Rhodobacter capsulatus (SB1003). We show that such an increase in fluorescence emission of extracellular pigment complexes (PC) from these photosynthetic bacteria depends on the concentration of the pigment and temperature and can also be modulated by the static magnetic field. The time-dependent enhanced emission disappears either at or below 300K or below a threshold sample concentration (0.1mg/ml). The enhanced emission reappears at this condition (T < 278K) if a static magnetic field (395mT) is introduced during fluorescence measurement. The time dependence of emission is expressed in terms of a first-order rate constant, k = dF/(Fdt). The sign of k shifts from positive to negative as PC concentration is lowered than a threshold value, implying onset of fluorescence decay (k < 0) rather than amplification (k > 0). At PC concentration higher than a threshold, k becomes negative if the temperature is lowered. But, surprisingly, at low temperature, a static magnetic field reverts the k value to positive. We explain the logical nature of k-switching and photo-dynamics of the aforesaid microbial fluorescence emission by aggregation of protoporphyrin rings present in the PC. While the simultaneous presence of decay in fluorescence and susceptibility to static magnetic field suggests the dominance of triplet states at low temperatures, the process is reversed by SMF-induced removal of spin degeneracy. At higher temperatures, the optical excitability and lack of magnetic response suggest the dominance of singlet states. We propose that the restructuring of the singlet-triplet distribution by intersystem crossing may be the basis of this logical behaviour. In context with microbial function, time-dependent enhancement of fluorescence also implies relay of red photons to the neighbouring microbes not directly exposed to the incident radiation, thus serving as an indirect photosynthetic regulator.

Influence of Pollution on Photosynthesis Pigment Content in Needles of Picea abies and Picea pungens in Conditions of Development of Iron Ore Deposits

Abstract We studied photosynthetic pigments in needles of Pісеа аbies and P. pungens in plantings exposed to aerotechnogenic influence of various levels in the big industrial center of steppe zone of Ukraine (Kryvyi Rih). We analyzed the pigment content in needles of the second year of life sampled from 30 to 40-year-old trees of both species in 6 monitoring sites for 5 months. For the needles of P. аbies and P. pungens from all the sites, we noticed the decreasing content of chlorophyll a (to 27.2 and 25.0%, respectively) and chlorophyll b (to 17.9 and 20.0%, respectively) from May till September, in comparison with background territory. At the same time, the content of carotenoids performing the protective function in photosynthetic reactions increased up to 26.1 and 24.0%, respectively. For P. аbies and P. pungens growing in conditions of intensive technogenic pressure, we ascertained that, during investigations, the sum of chlorophylls (a + b) rate decreased to 24.4 and 23.6%, respectively; ratio (a/b) decreased to 11.4 and 12.3%, respectively; ratio (chlorophylls [a + b]/carotenoids) also decreased to 30.1 and 38.0%, respectively, in comparison with plants from the least polluted site. It is shown that the most intensive negative influence on plantings is caused by industrial pollution and exhaust gases: the minimum or, more rarely, the maximum rates of pigment content appeared in needles of the plants exactly from these sites. Our research results demonstrate the feasibility of using the pigment complexes of P. аbies and P. pungens, with the assimilative apparatus sensitive to air pollution damage, as indicators of air environmental conditions.

Status of the Photosynthetic Apparatus of Wood Plants Damaged by Gall Mites

Журнал принимает на русском и английском языках статьи, представляющие результаты научных исследований в различных областях теоретической и прикладной экологии. Приоритет отдается научным статьям, основанным на явно сформулированных гипотезах.

Growth and development of Tagetes patula grown on vermisubstrate in closed ground

To study the growth and development of Tagetes patula on substrates of various composition, looking for vermicompost in a closed ground, we studied the biometric indicators and characteristics of the pigment complex (nitrogen balance Nbi, flavonols – Flv and chlorophyll – Ch). In the obtained results, the differences were statistically significant when comparing the median morphometric indices of plants on substrates BK-3a; and BK-2 for both periods of vermicomposting. It was established for substrates f vermicomposting for 90 days that there was a statistically significant difference between (P< 0.05) the compared samples of the Nbi index in the BK-2a; and BK-3a;, in chlorophyll when comparing the control with BK-3a;. It was noted that in vermisubstrates for a period 150 days, statistically significant differences were found in Flv in the BK-2б and BK-3б variants, with the Wilcoxon criterion P = 0.01; control with BK-2б, at P = 0.02. This indicates a significant effect of these substrates on the development of Tagetes patula. In this experiment we failed to prove a similar effect for the remaining soil types (P > 0.05).

Dependence of pigment content in meadow clover leaves on soil phosphorus level

In 2018-2019, the effect of different levels of soil phosphorus on the pigment complex of the clover (Trifolium pratense L.) leaves was assessed. Total chlorophyll content was 15.34-19.05 and 11.47-14.10 mg g- 1 dry matter, of which Chl a accounted for 9.64-11.36 and 6.67-7.98 mg g-1 (2018 and 2019 respectively). Carotenoids content varied within 2.69-3.12 and 1.52-1.88 mg g-1 in 2018 and 2019 respectively. Weight ratio of total chlorophyll/carotinoids (5.7-6.7 in 2018 and 6.8-9.6 in 2019) gives the grounds to consider that there was not disorders in structure of the pigment complexes of leaves in both year. There were statistically significant linkage of level of soil phosphorus with Chl a (r = 0.536-0.743) and Chl b (r = 0.725-0.748) in cooler conditions of 2019. In wormer 2018, these links were insignificant (Chl a = -0.146 to -0.286 and Chl b = -0.257 to -0.275). Correlation between phosphorus content in soil and carotenoids content in leaves was insignificant in all cases. Chl pigments showed a polynomial second order relationship with level of soil phosphorus. In 2019, these relations was statistically significant at p ≤ 0.05 (R2 = 0.68-0.76) for both chlorophylls. Under conditions of 2018 these relations was insignificant (R2 = 0.10-0.43).

Water-soluble complexes of orange pigments from Monascus sp. with HP-β-CD: Preparation, inclusion mechanism, and improved stability

Monascus pigments (Mps) have been utilized as natural food colourants in Asia for centuries. However, the poor water-solubility and photo-instability greatly restrict their applications in food industry. As a kind of orange Mps, monascorubrin (denoted as O1) is easy to react with substances containing amino groups (named amination reactions) and turn to red colour consequently. In this study, to maintain the original colour, solid inclusion complexes of O1 with hydroxypropyl-β-cyclodextrin (HP-β-CD) were prepared using freeze-drying method, and then investigated by SEM, FT-IR, PXRD, 1HNMR as well as molecular simulation method. Obtained results indicated that water solubility of O1 is significantly improved and its orange colour is successfully maintained at pH 3.5–9.0 upon complexation with HP-β-CD. Structural analysis suggested that O1 is encapsulated into the cavity of HP-β-CD, probably preventing it from amination reactions. Moreover, the pH and photo stability of Mps are markedly enhanced by complexation. This study provides an effective method for preparing water-soluble orange Mps that might be applicable in the beverage industry.

Вплив донора гідроген сульфіду на пігментний комплекс і продуктивність рослин пшениці (Triticum aestivum L.)

Вплив донора гідроген сульфіду на пігментний комплекс і продуктивність рослин пшениці (Triticum aestivum L.)

Grape skins as supplements for color development in Pinot noir wine

A particular challenge to making wine from Pinot noir grapes is the delicate flavor, light color and poor ageing potential of the wine. Conventional Pinot noir must preparations were compared with those made using a skin-based supplement to assess the impact on non-bleachable (sulfur resistant) pigments in the wine. When supplemented with either fresh grape pomace of Pinot noir, Pinot gris or Chardonnay grapes; Pinot noir grape marc or a commercial liquid grape skin extract, the additional seeds and pulp from the supplements were shown to compromise the development of stable pigments in the wine. To compare the relative merits of tannin derived from grape skins and seeds, the supplements used in a parallel experiment were the skins alone of the same three grape varieties and at six months bottle age, the stable pigment concentration was found to exceed the amount attributable to the supplement. A third experiment used fermented grape skins as the supplement, with 85% of the supplementary anthocyanin recovered as stable pigment complexes in the wine. Notably, this series of experiments showed that supplements containing grape seeds appeared to compromise non-bleachable pigment formation in the wine while skin only supplements stimulated their development.

CROP YIELD AND CONCENTRATION OF PHOTOSYNTHETIC PIGMENTS IN THE LEAVES OF THE SPRING WHEAT WHEN THEM SUFFERING FROM SEPTORIA BLIGHT

The authors explore the varieties and perspective breeding lines of the North-East Federal State Budgetary Scientific Institution with varying degrees of resistance to Septoria by yield and composition of the pigment complex in the leaves under the conditions of the Kirov region, were studied . Under the conditions of the growing season in 2017, characterized by excessive moisture, the strong development of a fungal infection (the degree of damage to the leaf is 22.0-62.3%) led to a decrease in the overall productivity of plants. The correlation coefficient between the defeat of Septoria and cereal and biological yields took average negative values (r = -0.43 and -0.44). The difference among the average parameters in the groups of moderately stable and susceptible varieties was 0.23 t/ha for grain yield and 0.49 t/ha for aboveground biomass. From the exit phase into the tube to heading an increase in the content of chlorophilic pigments and a decrease in the content of carotenoids per unit d ry mass of the leaf were observed in all varieties. However, in the group of susceptible varieties, the increase in chlorophyll a + b was less significant, and the content of carotenoids decreased more dramatically. In 2018, with a lower infectious load (the degree of damage was 9.5-47.0%), there were no significant differences in yield and the number of chlorophylls a and b in varieties of different resistance groups. In most cases, the content of chlorophylls a + b and carotenoids decreased by the flowering phase. C-64 and C-65 selection lines, tolerant to septoria, maintained a consistently high level of pigments. The correlation analysis reflects that the content of photosynthetic pigments in the exit phase into the tube was reliably associated with the development of the vegetative mass of plants, and with grain yield it happened in the flowering phase. No significant connection between the defeat of Septoria and the number of chlorophylls a and b in the flowering phase was found, but there was a decrease in the percentage of carotenoids in the total amount of pigments, depending on the extent of injury.

Biochemical markers of vital biodestruction in common oak (Quercus robur)

The wood of the common oak (Quercus robur L.) has high mechanical strength, elasticity and resistance to fracture. However, constitutional stability is not always able to provide the plants with reliable protection from wood-decay fungi, and the initial stages of biodegradation are difficult to determine. Therefore, this study concerns research on appropriate biochemical markers for early diagnostics of wood defects. The total content of phenolic compounds in leaves and wood was determined by a spectrophotometer Optizen Pop using Folin &amp; Ciocalteu’s phenol reagent; the flavonoid content in leaves – by adding solutions of aluminum chloride and sodium acetate to methanolic extracts; catechins content – by the reaction with vanillin reagent; the concentration of phenolic antioxidants – by Brand Williams; chlorophyll and carotenoids’ contents in leaves – by the formula for methanol extracts; the qualitative composition of phenolic compounds – by high performance liquid chromatography and highly effective thin-layer chromatography. During the planned felling of oak trees on the territory of the Boyar Forest Research Station, trees were found with signs of brown streak and biodestruction of wood. Brown streak in wood is caused by a polycondensation of phenolic compounds, which are deposited on the internal surfaces of tracheal elements. In cases of an increase in the total amount of oxidized polyphenols, the cell walls are also stained. Active oxidation processes in wood have a systemic nature for the plants and affect the physiological state of the assimilation apparatus. We determined that in leaves of the trees with signs of brown streak the total phenol content increases in comparison with the control by 1.6 times, as well as flavonoid and catechin content. Our research has shown that the complex of plastid pigments in common oak leaves does not significantly change in the early stages of destructive processes. Increase of brown streak and appearance of rot in wood are associated with slight increase in chlorophyll a to b ratio in leaves. Chromatographic profiling of the leaves showed that the presence of brown streak changes the content of individual phenolic compounds. The trees with brown rot have more substances with UV spectrum characteristic for kaempferol glycosides compared to the control. The results have shown that the biochemical profiles of the trees with signs of brown streak and brown rot differ from the control by the composition of low and medium polar compounds. The absence or presence of some individual phenolic components and their ratio in the leaves are considered as biochemical markers of hidden wood defects.

The Distribution of Chlorophyll a in the Bottom Sediments of Aniva Bay (Sea of Okhotsk)

This paper reports the first data on the content of plant pigments in the upper bottom sediment layer of Aniva Bay (Sea of Okhotsk) located in the temperate-monsoon climatic zone. A positive relationship was found between the concentration of sedimentary chlorophyll a and its total content in the water column, which reflects a prevalent role of phytoplankton in the formation of the sedimentary pigment complex. A significant variability of the spatial distribution of the pigments in the bay is shown to be caused by the hydrological–hydrochemical parameters and characteristics of the bottom sediments. The contents of chlorophyll a and phaeopigments in sediments showed values of the oligotrophic category and averaged 6.5 ± 0.7 μg/g of dry sediment or 0.47 ± 0.06 mg/g of organic matter.

Various antioxidant responses to hyperthermia in anatomically different species of the genus Rosa

The heat and drought resistance of plants depend on their anatomical and biochemical features. In the present study, the adaptive features of three species of wild rose (Rosaceae, Rosales) under the short-term impact of high-temperature stress have been characterized. Plants of the species Rosa donetzica Dubovik, R. reversa Waldst. et Kit. and R. spinosissima L. were exposed to a temperature of 40 degrees C for 3 hours, following which peroxidase and superoxide dismutase activity, photosynthetic pigments and flavonoids’ content, and lipid peroxide oxidation level in the leaf were determined. In our investigation, the anatomical structure of leaves and drought resistance of three species of Rosa were studied. Xeromorphic features are the most expressed for R. reversa and R. spinosissima and almost absent for R. donetzica. It has been established that R. spinosissima is photophilous whereas R. donetzica is shade-tolerant. The relatively lower development of epidermic tissue in R. donetzica could probably contribute to more active destruction of the pigment complex under high temperature stress. The obtained data about changes in activity of peroxidase, superoxide dismutase, content of photosynthetic pigments and flavonoids, and level of lipid peroxidation indicate the low heat resistance of R. donetzica in comparison with the other two species. R. reversa, R. spinosissima were more tolerant to short-term hyperthermia. They showed faster antioxidant response, mainly due to the induction of peroxidase activity under stress. The species with the most expressed xerophytic features of anatomical structures have rapid antioxidant response and are more resistant to short-term hyperthermia. The induction of some activity of antioxidant enzymes "in reserve" is a less effective form of adaptation in wild roses. Such activation of enzymes is observed in plants with a more mesophytic structure. Flavonoids and superoxide dismutase were thermolabile to short-term influence of high temperature; therefore they play an insignificant role as antioxidants in the protecton against oxidative stress caused by high temperature stress in wild roses.

Leaf pigment complex of spring soft wheat cultivars of different maturity groups under different moisture regimes

Creation of new higher productive cultivars of cereal crops is often linked with straightening of degree of resistance to abiotic environmental factors. Indirectly this degree of resistance could be estimated on quantitative change in leaf pigment composition. There is practical interest to compare the activity of pigment complex of flag leaves of wheat cultivars belonging to different maturity groups that could give information on direction of breeding improvement of plant physiological-and-genetic traits under different ecological conditions. Plants of nine breeding lines and two standard cultivars grew in 20162018 at the experimental field of FARC of North-East (Kirov) under continental climate conditions with moderately cold winter and warm summer. The study of flag leaves pigment complex allows to discover differences between early and middle-ripening cultivars on investigated parameters in different hydrothermal conditions. During the study years, middle-ripening cultivars accumulated more chlorophyll a than the early ones. On average this excess was about 10%. The studied cultivars were differed on distribution of pigment between structural parts of photosystems: middle-ripening cultivars had more chlorophyll a in reaction centers whereas the amount of the pigment in light-harvesting complexes was not differed. Hydrothermal conditions significantly influenced the differences between cultivar groups. Thus, under dry conditions the content of chlorophyll b and carotenoids in flag leaves of cultivars belonging to both group of maturity had no significant differences. Under normal or moist conditions middle-ripening cultivars contained 11,012,6% more chlorophyll b and 7,623,1% more carotenoids than the early cultivars. Under dry conditions the two groups of cultivars significantly differed on mass ratio chlorophyll a/b: in the middle-ripening cultivars it was 5,0% higher than in the early ones. Based on chlorophyll a and b content at flowering stage breeding lines С-64, С-65, С-103, and С-129 were selected. The amount of chlorophyll in these genotypes was significantly higher than in Margarita standard cultivar. Within the group of early cultivars, no one exceeded Bazhenka standard by the pigment content. The cultivars of this group reacted on abiotic growing conditions change very much (the amount of precipitations and air temperature): the coefficients of chlorophyll a content variation were 6,516,3%, of chlorophyll b content 26,929,7%, of carotenoids content 4,117,2%.