Fruit growing
and viticulture of South Russia
Management of soil fertility
The results of the study of microbial communities of the arable layer of two types of zonal soils under the peach tree in the Southern Region are presented. The substantiation of relevance of carrying out system monitoring of microbiological diversity under the conditions of garden monoculture is made. The main purpose of the work is a comparative assessment of changes in microbiological indicators of brown forest slightly unsaturated soil and leached chernozem in anthropogenically transformed ecosystems. The experimental plots were located in the plantations of fruitbearing peach of high-yielding varieties zoned in the region in the humid subtropical climate of the Black sea coast and the Central zone of the Krasnodar territory. The microflora features of upper (arable) soil layer were analyzed. Based on the climatic feature of region the soil for research was selected in the winter period in the first decade of December. For microbiological studies, the main groups of soil microorganisms reducers of plant residues that form a microbial complex were selected . The main morphological groups (bacteria, actinobacteria, and micromycetes) of soil microorganisms were accounted for using traditional methods. The analysis of the number of microorganisms was carried out in relation to agrochemical indicators of soils and weather conditions during the sampling period. The structure of the microbocenosis was quantitatively dominated by the physiological group of saprophytic bacteria. On average, the number of actinobacteria and micromycetes was 1-2 orders of magnitude lower. The arable layer of leached black soil under the peach orchard was characterized by higher values of saprotrophic aerobic bacteria in comparison with brown soil. The content of producers of antibiotic substances actinobacteria in leached chernozem was 2.4 times lower. The population of the upper layer of two types of soil containing the bulk of plant residues differed slightly. Some excess of the content of soil fungi in the borozem is probably due to higher soil acidity. The revealed features of the composition of the microbocenosis of two types of soils are the basis for continuing the biomonitoring, which allows using agricultural methods to develop the possible ways of rational use of microorganisms activity to increase in soil fertility.
It is presents the results of study of the effect of turfing the row spacing of an apple orchard with legumes-cereals grass mixtures on the water penetration of the soil, as well as on the accumulation in the soil of detritus organic substance. The research carried out found that in the row spacing of apple orchards with the sowing of legumes and cereals, the productivity of biomass depended on the ratio of red clover and Timothy meadow. When the ratio of red clover Timothy meadow 1: 1, the mass of dry matter in the soil of row spacing on average for 3 years was 6.52 t/ha. An increase in the cenosis of red clover to 70 % increased in the amount of dry matter for 3 years up to 7.10 t/ha. The most amount of labile organic matter in the form of detritus is formed in the row spacing soil in the variant with clover and Timothy meadow in the ratio of 7:3. On average, over 3 years, the amount of detritus in the row spacing soil was 0.25%, which is almost 2 times higher than its quantity in the control variant. Studies carried out have shown that the composition of herbaceous vegetation used in the drawing of row spacing also affects the water penetration of the soil. The amount of absorbed water with natural turf was minimal and for the first hour of 1089 ml, for the second hour 961 ml, and the third hour 578 ml. In case of sowing in the rows spacing of garden the clover-Timothy meadow grass mixture the amount of soil absorbed water was greater. The maximum amount of water was absorbed by soil in the variant with sowing of clover and Timothy grass in the ratio of 7:3.
As a result of studies of the myological composition of the ampelocenoses soils with a different content system, in 2019, eight genera of soil micromycetes (Mucor, Trichoderma, Penicillium, Aspergillus, Fusarium, Alternaria, Cladosporium, Vertecillium) were isolated. Soil microbiota was found to differ depending on the season and soil keeping system. The greatest variety of micromycetes was noted in the variants with the additional introduction of organic substances. In the spring, the species of the Trichoderma sp. genus dominated in the complex of isolated soil fungi with a soil system sodding and black fallow + organic fertilizers. In the version with a black fallow soil system in the spring, the dominant species were the species of the genus Penicillium sp. and Trichoderma sp oreover, the species of Trichoderma sp. was isolated only in the soil layer of 15-30 cm. In the summer, in the variants Sodding and black fallow + organic fertilizers, the species composition of soil micromycetes expanded, while the frequency of occurrence of the Trichoderma sp. species, dominated in spring, in the 0-15 cm layer was only 2,6%, and in the layer of 15-30 cm this species was not isolated. The fungus of the Trichoderma genus in the version with a black fallow soil + organic fertilizer system retained their dominant position, but their number decreased by 1.6 times. In the variant, black fallow in the soil layer of 0-15 cm the fungi of the Penicillium sp. genus dominates preserved, and in a layer of 15-30 cm, the composition was rearranged, to domination the genus Penicillium sp. and Aspergillus sp. species.
The prospects of soil metagenomics using to determine the soil quality of garden cenoses are discussed in this article. Soil quality, along with its fertility, is considered as the most important characteristic of any soil ecosystem, especially under intensification anthropogenic influence. The development of metagenomic studies of soil microorganisms is due to the fact that they are the basis for studying the ecosystems, especially for agricultural purposes. The emergence of new analysis tools contributes to the study of the structural and functional organization of soil microbial biocenoses. An important feature of metagenomic research is that there is no need for isolation and cultivation of microorganisms. This will make it possible to carry out a more complete analysis of the structure of the soil microbial community, to identify the features of the structure of the rhizosphere microflora depending on the duration of growing the perennial plants in a monoculture, and to identify new bioindicators of soil fatigue. The necessary approaches for a complete structural and functional assessment of the soil microbiome are presented, and the goals and objectives of metagenomic analysis are outlined in the article. It is shown that the study of metagenomic analysis of soils makes it possible to move to a new system level of research on the biodiversity of soil ecosystems. This transition leads to a paradigm shift and opens the way to understan the processes that occur in the soils under intensive agricultural use. The available developments in the field of soil metagenome indicate the possibility of using this information as an integral indicator of soil quality in the garden agrocenoses and their functioning, as well as the prospects for use the research results to further improving the methods of biologization and ecologization of agricultural production and fruit growing in particular.
The problems of transformation of chernozem soils properties of garden cenoses during drip irrigation with mineralized water are considered. The widespread introduction of drip irrigation with the mineral fertilizers to cultivate fruit plantations using intensive technologies has created a number of environmental problems. The forced use of mineralized water for irrigation due to limited resources contributes to changes in the properties of chernozem soils, in recent years. It is manifested fruit plants oppression against the background of the constant use of fertigation in the intensive fruit plantations. It was found that drip irrigation of apple orchards with mineralized water contributed to the accumulation of water-soluble salts in the main zone of soil moisture. The use of long-term drip the irrigation in fruit plantations led to the gradual leaching of calcium ions from the zones of local soil moisture. The proportion of magnesium in the soil-absorbing complex as a result of irrigation increased in 20.8-32.8 % of the amount of absorbed bases. On the plot with oppressed apple-trees, a higher content of exchangeable magnesium in the soil was noted in comparison with apple plantations under a satisfactory condition. The increased content of sodium in irrigation water led to a significant increase in its concentration in the places of localization of irrigation water in areas with both depressed and apple trees in satisfactory condition. The content of exchangeable sodium in the soil layer 0-30 cm under the droppers increased in 0.94-1.74 mg-eq./100 g. of soil. The share of exchangeable sodium in the soil absorbing complex in the zone of local soil moisture increased in 3.1-5.3 % of the amount of absorbed bases, which indicates a weak degree of soil salinity. Analysis of apple varieties productivity indicates the influence of tree growth conditions the yield and fruit quality, the share of the influence of soil conditions was 81.8-93.6 %.