Influence of ecological conditions of various habitats on individual morpho-biological and physiological features of Hedysarum grandiflorum pall seeds

The large-flowered sweetvetch (Hedysarum grandiflorum Pall.) is a perennial beautiful-flowering plant with a narrow ecological amplitude, promising for introduction and cultivation. Under controlled conditions using the LI-6800 instrument, LI-COR, USA, the dynamics of indicators of photosynthesis intensity, transpiration and accompanying physiological processes related to gas exchange in H. grandiflorum seedling leaves under different light levels (1500, 1000, 500, 200, 100, 50, 0 µM/m2/s) in saline conditions was studied. It has been established that photosynthetic apparatus of H. grandiflorum seedlings adapts well enough to saline conditions and significant photosynthesis suppression by 17.4 % is observed only at PAR level of 300 µM/m²/s¹. At the same time, a significant decrease in the rate of water evaporation by the surface of cotyledon leaves under the influence of salinity conditions — by 36.5–54.3 % is observed. The obtained data indicate a potentially high adaptive capacity of H. grandiflorum seedlings due to self-regulation of gas exchange processes.

Introduction Issues: Influence of Salinity on Gas Exchange Processes of Seedlings Hedysarum Grandiflorum Pall.

Dumacheva,

USOL'CEVA,

MAKSIMOVA

et al. 2024

Comparative Analysis of the Rate of Co2 Assimilation in Annual Trifolium Species at the Juvenile Stage of Ontogenesis

Dumacheva,

Kostenko,

Chernyavskih

et al. 2024

The parameters of photosynthesis, dark respiration and intercellular CO2 concentration were studied in three species of annual clovers: Trifolium resupinatum, T. alexandrinum, T. incarnatum. Significant differences in the parameters of the rate of carbon dioxide assimilation between the studied species were established in the experiment. The maximum value of dark respiration and CO2 assimilation rate was observed in the seedling leaves of T. alexandrinum seedlings. The equations of light curves of CO2 assimilation and intercellular CO2 concentration were calculated. High approximation coefficients were found: from 0.945 to 0.989 for photosynthesis light curves; from 0.683 to 0.983 for intercellular CO2 concentrations.

Mobilizations of Genetic Resources of Perennial and Annual Grasses in the Cretaceous South of the Central Russian

Dumacheva,

GONChAROVA,

KALAShNIKOVA

et al. 2024

The article discusses the results of joint research by scientists and graduate students of the V. R. Williams Federal Scientific Centre for Forage Production and Agroecology and Belgorod State National Research University on the search and selection of valuable sources of breeding traits and mobilization of plant genetic resources. V. R. Williams and Belgorod State National Research University on search and selection of valuable sources of breeding traits and mobilization of plant genetic resources on the territory of the Cretaceous south of the Central Russian Upland. As a result, the sources of valuable economic traits of annual and perennial grasses (alfalfa sickle, large-flowered sweetvetch, oriental goats-rue grass, strawberry clover, phacelia tansy-leaved and others) were identified in terms of seed productivity and productivity of aboveground phytomass, cladding, duration of flowering period.