The article describes the influence of different cultivation backgrounds on the yield structure and productivity in soft spring wheat of the zoned variety «Svirel» in the steppe of the Krasnoyarsk territory. It was found that the productive tillering and grains number in the ear from the crop structure elements in spring wheat variety «Svirel» had the best reaction to the using of fertilizers and chemical protection. The maximum average yield increase was observed when wheat was sown on a fertilized background with using of a full range of plant protection products, the minimum after previous grain without using of intensification agents.

Green spaces such as parks and street trees represent a key component of urban ecosystems. Planting trees and shrubs in cities provides a number of environmental, economic, social and health benefits and also preserves biodiversity in highly urbanized areas. The key problem of the ecological landscaping in Central Siberia is to select plants species resistant both to high level of pollutants and to large variations in temperature. Basing on the comparative study of growth characteristics and physiological state of plants in natural and urban ecosystems we recommend 31 plants species of 16 families for ecological landscaping. Recommended species for ecological landscaping in Central Siberia are Abies sibirica, Acer platanoide, Amorpha fruticosa, Berberis thunbergii, Berberis vulgaris, Cornus alba, Cotoneaster lucidus, Crataegus sanguine, Dasiphora spp., Forsythia spp., Juglans mandshurica, Juniperus Sabina, Larix sibirica, Philadelphus spp., Physocarpus opulifolius, Picea obovata, Picea pungens, Pinus sibirica, Pinus sylvestris, Ribes aureum, Rosa rugosa, Salix alba, Salix ledebouriana, Salix purpurea, Sorbaria sorbifolia, Sorbus aucuparia, Spiraea salicifolia, Syringa josikaea, Tamarix ramosissima, Tilia cordata, Viburnum opulus. Coniferous plants are presented with 7 species of 5 genera. Deciduous plants are presented with 24 species of 21 genera. The list of recommended plants species includes both trees and shrubs.

The aim of the work was to study the ecological plasticity of soft spring wheat. To achieve this goal the following tasks were defined: to evaluate varieties of soft spring wheat by yield, elements of environmental plasticity and stability, using the principle of ranking varieties, to evaluate their adaptability to environmental conditions. Varieties of soft spring wheat «Altaiskaya 70», «Kanskaya», «Novosibirskaya 15», «Novosibirskaya 29», «Novosibirskaya 31», «Novosibirskaya 41», «Omskaya 32» and «Vavenkov’s memory» were the objects of research. The parameters of ecological plasticity and stability (bi, σ) were calculated using the method of S. A. Eberhart and W. A. Russell, the homeostatic index (Hom) was calculated using the formula of V. V. Khangildin, and stability parameters of spring wheat were calculated using the method of E. D. Nettevich. The varieties «Kanskaya», «Omskaya 32», «Altaiskaya 70»realized their yield potential in the conditions of the variety testing area to a greater extent. Comparison of different methods for evaluating varieties for stability and plasticity showed that their resolution was not the same. The most complete information is provided by the use of several methods, while it is more convenient to use the principle of ranking varieties by all parameters and to evaluate them by the sum of points. Under contrasting growing onditions, the varieties showed different adaptive properties in terms of yield. It responded to improvements in growing conditions well and reduced yields in adverse conditions to a lesser extent.

The effects of previous crop, fertilizers and pesticides on the wheat yield and the cost efficiency of wheat production in Siberia were studied in two-year field experiment. It was found that the yield mostly depends on the previous crop and pesticides, whereas the fertilizer demonstrated relatively slight effect in the year favourable for wheat growth and no effect in the year unfavourable for wheat growth. Cost-effectiveness analysis showed that the most effective way to reduce the environmental impact of wheat production in Siberia is the use of fallow in crop rotation scheme. Usage of fallow without chemical fertilisers provides higher yield than variants with fertilisers and pesticides where wheat was used as a previous crop. Cost efficiency of variant with fallow was 20.8% what is comparable with cost efficiency of the most cost effective variants (fallow as a as a previous crop + pesticides with cost efficiency of 36.6% and wheat as a previous crop + fertilizers with cost efficiency of 30.4%).

Improvement of dendrochronological crops yield reconstruction by separate application of earlywood and latewood width chronologies succeeded in rain-fed semiarid region. (1) Background: Tree-ring width chronologies have been successfully applied for crops yield reconstruction models. We propose application of separated earlywood and latewood width chronologies as possible predictors improving the fitness of reconstruction models. (2) Methods: The generalized yield series of main crops (spring wheat, spring barley, oats) were investigated in rain-fed and irrigated areas in semiarid steppes of South Siberia. Chronologies of earlywood, latewood, and total ring width of Siberian larch (Larix sibirica Ledeb.) growing in forest-steppe in the middle of the study area were tested as predictors of yield reconstruction models. (3) Results: In the rain-fed territory, separation of earlywood and latewood allowed increasing variation of yield explained by reconstruction model from 17.4 to 20.5%, whereas total climatic-driven component of variation was 41.5%. However, both tree-ring based models explained only 7.7% of yield variation in the irrigated territory (climate inclusion increased it to 34.8%). Low temperature sensitivity of larch growth was the main limitation of the model. A 240-year (1780–2019) history of crop failures and yield variation dynamics were estimated from the actual data and the best reconstruction model. (4) Conclusions: Presently in the study region, breeding of the environment-resistant crops varieties compensates the increase of temperature in the yield dynamics, preventing severe harvest losses. Tree-ring based reconstructions may help to understand and forecast response of the crops to the climatic variability, and also the probability of crop failures, particularly in the rain-fed territories.