Oilseeds as a resource base for biofuel production

The indicators of oilseeds and oils obtained from them characterizing the possibility of their use in the production of biofuel are analyzed. The results of the study of oilseed radish as a crop, which is a potential resource base for biofuel production, are presented. Chromatographic studies of the oil obtained from oilseed radish are performed, and its viscosity, density and calorific v alue aredetermined.

Influence of the sowing time and mineral fertilizers on the productivity of annual grass mixtures

The productivity of annual feed grass mixtures (vetch + oats, Sudan grass + white mustard, Sudan grass + oilseed radish), sown after the winter rye harvesting during the “shooting” phase (the 1st time of sowing), during the “heading” phase (the 2nd time of sowing), and during the phase of complete ripeness (the 3d time of sowing), was studied in the conditions of forest-steppe soils of the Volga Region (the Republic of Mordovia). The experiment was carried out in 2018-2020 on heavy loamy soils against the background of three doses of mineral fertilizers use (without fertilizers, N16P16K16 + N30, N16P16K16 + N60). It has been established that the duration of vegetation of feed mixtures according to the time of sowing when harvesting for green mass was: at the first the time of sowing - 63-85 days, at the second - 63-76 days, at the third - 56-62 days. The highest height of the plant was at the first time of sowing with the use of fertilizers at a dose of N16P16K16 + N60, the lowest - at the third time of sowing. The highest growth was achieved by Sudan grass (48-116 cm), the lowest - by the mixture of vetch and oats (18-67 cm). The highest yield of green mass (14.0 t/ha) was observed when cultivating Sudan grass mixed with oilseed radish on the background of N16P16K16 + N60 at the first time of sowing. For mixture of Sudan grass with white mustard, the yield was 2-7 % lower, and for vetch + oats mixture - 32-45 % lower. The same was observed according to the yield of dry matter and feed units. As to the protein content, mixtures of Sudan grass with cruciferous crops exceeded the vetch + oats mixture by 7-26 %. The fiber content in the grass mixtures was decreasing from the first time of sowing to the last. The greatest amount of fiber (28.11-28.72 %) was observed during the second time of sowing. The economic assessment showed that the cultivation of annual grass mixtures after winter rye without mineral fertilizers was the most cost-effective (29-208 %). The highest efficiency (202-208 %) was provided by the mixture of Sudan grass with oilseed radish and white mustard.

​The Impact of Growing Legume Plants under Conditions of Biologization and Soil Cultivation on Chernozem Fertility and Productivity of Rotation Crops

Background: The combined use of green manure and legumes in binary legume-crop mixtures allows farmers to efficiently produce a sufficient amount of human food and animal feed. The purpose of this study is examine how biologization and the use of different soil cultivation techniques in legume cropping affects chernozem soil fertility and productivity of rotation crops. Methods: The studies were conducted between 2017 and 2019 in 3 crop rotations. The first (control) crop rotation comprised of a clean fallow phase, winter wheat, barley and sunflower. The second crop rotation was that of green-manure fallow (clover), winter wheat, barley, sunflower and clover with oilseed radish as green manure. The third crop rotation included alfalfa, winter wheat combined with alfalfa, followed by barley, followed by sunflower and alfalfa with oilseed radish as green manure. Result: The three-year data indicated that there was an improvement in the physical properties of soil. The water resistance of soil aggregates increased by 9.7 per cent. There was a steady tendency towards an increase in detritus content (1.5 times), the amount of soil aggregates (one-third) and water resistance of the soil aggregates (9 per cent).

Impact of Cover Crop Monocultures and Mixtures on Organic Carbon Contents of Soil Aggregates

Cover crops are considered an integral component of agroecosystems because of their positive impacts on biotic and abiotic indicators of soil health. At present, we know little about the impact of cover crop types and diversity on the organic carbon (OC) contents of different soil aggregate-size classes. In this study, we investigated the effect of cover plant diversity on OC contents of different soil aggregates, such as macro- (<2000–500 μm), meso- (<500–250 μm), and micro-aggregates (<250 μm). Our experiment included a total of 12 experimental treatments in triplicate; six different monoculture treatments such as chickling vetch (Vicia villosa), crimson clover (Trifolium incarnatum), hairy vetch (Vicia villosa), field peas (Pisum sativum), oilseed radish (Raphanus sativus), and mighty mustard (Brassica juncea), and their three- and six-species mixture treatments, including one unplanted control treatment. We performed this experiment usingdeep pots that contained soil collected from a corn-soybean rotation field. At vegetative maturity of cover plants (about 70 days), we took soil samples, and the soil aggregate-size classes were separated by the dry sieving. We hypothesized that cover crop type and diversity will improve OC contents of different soil aggregate-size classes. We found that cover plant species richness weakly positively increased OC contents of soil macro-aggregates (p = 0.056), whereas other aggregate-size classes did not respond to cover crop diversity gradient. Similarly, the OC contents of macroaggregates varied significantly (p = 0.013) under cover crop treatments, though neither monoculture nor mixture treatments showed significantly higher OC contents than the control treatment in this short-term experiment. Interestingly, the inclusion of hairy vetch and oilseed radish increased and decreased the OC contents of macro- and micro-aggregates, respectively. Moreover, we found a positive correlation between shoot biomass and OC contents of macroaggregates. Overall, our results suggest that species-rich rather than -poor communities may improve OC contents of soil macroaggregates, which constitute a major portion of soil systems, and are also considered as important indicators of soil functions.

Soil Carbon, Glomalin, And Aggregation in Onion Crop Under No-Tillage with Cover Crops or Conventional Tillage Systems for Eight Years

Crop systems using cover crops affect soil physical, chemical, and biological attributes, including aggregate formation. This work aims to evaluate winter cover crop species' effect on soil total organic carbon, glomalin, and aggregation in areas with onion crops in a no-tillage vegetable production system (NTVS) and conventional tillage system (CTS) for eight years. The experiment treatments were: control, with natural vegetation(NV); black oats (Avena strigosa); rye(Secale cereale);oilseed radish(Raphanus sativus);intercropped black oats and oilseed radish; intercropped rye and oilseed radish; and a conventional tillage systems area. A 33-year old adjacent secondary forest was evaluated as a reference for undisturbed conditions. We assessed soil total organic carbon, total glomalin, and easily extractable glomalin in three soil layers (0-5, 5-10, and 10-20 cm depth). Undisturbed samples were used to quantify soil aggregate stability, aggregation indexes (weighted mean diameter; geometric mean diameter), aggregate mass distribution (macroaggregates, mesoaggregates), and macroaggregate carbon contents. The conventional tillage areas had the lowest weighted mean soil aggregate diameter, geometric mean diameter, and macroaggregate mass. Those areas also had the lowest bulk soil and aggregate organic carbon contents and the lowest total and easily extractable glomalin. Winter cover crops' use resulted in a 10% higher aggregate weighted mean diameter and geometric mean diameter. Areas with cover crops had 13% higher organic carbon contents in aggregates and 17% higher macroaggregate mass than conventional tillage areas. The highest values of total and easily extracted glomalin occurred in plots with black oats. Winter cover crops, single or intercropped, improved physical attributes of soils with onion crops under not-tillage compared to conventional tillage areas.

On the participation of heterotrophic microorganisms in initial soil formation on waste from iron ore agglomeration

The results of studies of the development of heterotrophic microorganisms in embryosemes formed on the sand waste of iron ore agglomeration in Western Siberia are presented. At the initial stage of soil for-mation, low values of actual acidity and very low humus values were found in the initial embryosemes. It is established that such habitats are phytiotoxic, which is confirmed by data on the germination of seeds and the growth of seedlings: oats, oilseed radish and white mustard. It is proved that heterotrophic micro-organisms are adapted to life in embryos. Azotobacteria retain vital activity, thanks to toxin and mucus formation, and actively multiply. Micromycetes exhibit dimorphism-yeast and mycelial growth types, which expands the possibilities of their vegetative reproduction and population preservation. It was re-vealed that organo-accumulative embryos are the most viable for plants and microorganisms. For the first time, the glow of mold fungi and Azotobacter under cereal plants and pine plantations was recorded. It is suggested that the emission of light energy, the presence of oxidases of microorganisms and plant lignin contribute to humification in an oligotrophic environment

Soil phosphorus availability and uptake by mycorrhizal and non-mycorrhizal plants in an onion no-tillage system

ABSTRACT: Onion is an important vegetable crop, predominantly grown under conventional tillage system management. Alternatively, the vegetable no-tillage system uses cover crops to form a residue layer, which improves soil physical, chemical, and biological attributes. Aiming to understand the interaction of mycorrhizal and non-mycorrhizal cover crops, phosphatase activity, and soil phosphorus availability and uptake by plants, a no-tillage vegetable production system experiment with onion was carried out in Ituporanga, Southern Brazil. The treatments were black oats (Avena strigosa); rye (Secale cereale); oilseed radish (Raphanus sativus); rye + oilseed radish; black oats + oilseed radish, and a control with spontaneous plants. Additionally, two plots, a conventional tillage system area and a forest, both adjacent to the experiment, were evaluated. We measured cover crop biomass, onion yield, acid phosphatase activity, and resin-extracted phosphorus in the soil, shoot and root phosphorus content, and root colonization in cover crops, spontaneous plants, and onions. The treatments with cover crops had the highest plant biomass in winter and onion yield. Available soil phosphorus and acid phosphatase activity were higher in no-tillage plots than in the conventional tillage system area. The presence of non-mycorrhizal oilseed radish was associated with decreased colonization of rye and onion roots by arbuscular mycorrhizal fungi. No-tillage areas with cover crops or spontaneous plants in winter accumulated more phosphorus than conventional tillage system areas. The conventional tillage system showed adverse effects on most soil attributes, as shown by a Principal Component Analysis.