Temperature and salinity are important abiotic factors for aquatic invertebrates. We investigated the influence of different salinity regimes on thermotolerance, energy metabolism and cellular stress defense mechanisms in amphipods Gammarus lacustris Sars from two populations. We exposed amphipods to different thermal scenarios and determined their survival as well as activity of major antioxidant enzymes (peroxidase, catalase, glutathione S-transferase) and parameters of energy metabolism (content of glucose, glycogen, ATP, ADP, AMP and lactate). Amphipods from a freshwater population were more sensitive to the thermal challenge, showing higher mortality during acute and gradual temperature change compared to their counterparts from a saline lake. A more thermotolerant population from a saline lake had high activity of antioxidant enzymes. The energy limitations of the freshwater population (indicated by low baseline glucose levels, downward shift of the critical temperature of aerobic metabolism and inability to maintain steady-state ATP levels during warming) was observed, possibly reflecting a trade-off between the energy demands for osmoregulation under the hypo-osmotic condition of a freshwater environment and protection against temperature stress.

The vertical distribution and abundance of Gammarus lacustris in the pelagic zone of two fishless meromictic lakes, L. Shira and L. Shunet, in Southern Siberia (Russia), was studied with the underwater video recording system and using vertical hauls. In both lakes, during summer stratification, Gammarus was distributed non-homogenously, with a stable peak in the metalimnion. The average depth of Gammarus population in the pelagic zone was significantly correlated with the depth of the thermocline. Gammarus abundances obtained using vertical plankton hauls with net were quite comparable with those obtained from video records. The peak abundance of Gammarus in the pelagic zone of the lakes observed with underwater video amounted up to 400 individuals m -2 , while the peak animal densities in the metalimnion reached 50 ind. m -3 . The data are compared with previously published abundances of Gammarus in the littoral of Lake Shira. Both littoral and pelagic can be equally important habitats for amphipods in meromictic lakes. The absence of fish in the pelagic zone, high oxygen concentration, low water temperature, increased seston concentration, elevated water density in the metalimnion and the anoxic hypolimnion can be the most probable combination of factors that are responsible for the peak of Gammarus in the metalimnion of these lakes.

Abstract. The authors present the results of a study of the genetic characteristics of Carum carvi seeds (Carum carvi) in the northern forest-steppe of the Tyumen region. The purpose of the work is to study the genetic resources of medicinal and spicy – aromatic plants of the Northern Trans-Urals, to distinguish endemic forms from Carum carvi populations with valuable economic and biological characteristics. The area of priority areas is the study of this culture with a subsequent increase in the production of medicinal raw materials for the pharmaceutical and food industries. The novelty lies in the fact that for the first time in the northern forest-steppe of the Tyumen region at the Scientific Research Institute of Agricultural Sciences of the Northern Trans-Urals, a branch of the Federal Research Center of the Tyumen Scientific Center of the SB RAS, the feed production department, endemic forms from Carum carvi populations were studied. The variety Aromatnyy was used as a standard. Methods. Counts and observations were carried out according to the experimental technique. The collection nursery contains 200 samples of endemic forms of the 2nd year of life, of which 12 samples of this species were isolated. Of the forms previously introduced and adapted to local conditions, there were 150 plants of the same species of the 2nd year of life planted in 2017, of which 12 plants were isolated. The plot size is 9 m2. Results. In a collection nursery 350 samples of Carum carvi seeds of ordinary endemic and introduced forms of plants were studied. With the high seed yield and the highest content of essential oils in relation to the standard Aromatnyy variety, in the study of endemic forms, two samples of the second year of life, No. 1-2-2, and No. 1-4-2, were distinguished, and when studying introduced samples by seed productivity, the following were distinguished: No. 12-1-2 and No. 2-4-1 – 27.0 g per plant. The selected population samples for economically useful traits are a valuable genetic source for the yield of raw materials and the accumulation of essential oils.

The results of study of yield and protein content in grains of chaffy and naked barley in the experiment with the increasing rates of mineral fertilizers were described. The relationship between the nitrogen content in the leaves of barley plants and protein content in grains were calculated. For the Acha variety the optimal fertilizer rate was based on the yield of 3.0 t/ha. Higher fertilizer rates were needed to realize yield potential of the Philadelphia and Nudum 95 varieties based on the yield of 5.0 t/ha. The highest protein content in the barley grain was formed in the options with the calculated rate of fertilizers for the yield of 5 t/ha: Acha-15%; Philadelphia-13.5%; Nudum 95-18%. A positive relationship was established between the nitrogen content in the leaves and the amount of protein in the grain: r = 0.934; 0.880; 0.877 for the Acha, Philadelphia, Nudum 95 varieties, respectively. In collecting protein from the area unit, the Acha variety has shown the best results, the advantage of which was 131 kg/ha compared to the Philadelphia variety, and 95-127 kg/ha compared to Nudum 95.

The research was conducted in 2011-2013 in the northern forest-steppe of the Tyumen region. The vegetation period of hulless barley samples ranged from 63 to 80 days. The samples with the length of stages-seedling-heading-38-42 days and heading-ripening-29-33 days produced the yield higher than the standard Omsk bare-grain 1 by 2.9-60.6%. The largest number of samples (56.6%) formed the eighth group where protein content was 15.1-17.0%; 30.2% of the samples appeared to be in the ninth group (17.1-20.1%), and 13.2%-in the seventh (14.0-14.9%). The highest average 1000 grain weight was observed in barley samples of the ninth group (42.8 g). The samples of the eighth group showed a lower characteristic value (40.3 g) while the samples of the seventh group where protein content was 14.0-14.9% had the lowest value (39.9 g). The average starch content in the samples of all groups was at the level of 58.8-60.5%. The limits of starch variations in barley samples were higher in the seventh group with high protein content. In the same group, the variation range of a trait was much higher (14.2%). The grain-unit g/cm 3 increased on average from 6.5 (seventh group) to 6.7 (ninth group). The largest variation range was in the eighth group (2.0). A reliable positive correlation with yielding properties was found in the group with very high protein content (17.1-20.1%). The highest correlation coefficients were found by interrelations with: protein content (r=0.400), 1000 grain weight (r=0.687) and grain-unit g/cm 3 (r=0.656). A reliable negatively-associated relationship was found between the starch content and the yield (r=-0.382). The following samples showed high resistance to stem rust (Puccinia graminis Pers), namely: Local (k-3115, Tajikistan), Local (k-3170, Tajikistan), Local (k-3772, Dagestan), Local (k-19709, Denmark), Local (to-21747, Dagestan). By lodging resistance at the level of 9 points, the following samples were distinguished, namely: Local (k-3038, Turkmenistan), Local (k-3165, Tajikistan), Local (k-3938, Mongolia), Buck CDC (k-30173, Canada). In the ninth group with high protein content (17.1-20.1) the local sample from Tajikistan (K-3770) formed standard starch content (60.8%). The local cultivars from Iran (k-3082) and Georgia (k-838) had the highest 1000 grain weight (52.7-55.5 g).