Marked Changes in Biochar’s Ability to Directly Immobilize Cd in Soil: Implication for Biochar Remediation of Cd Contaminated Soil

To investigate the change in biochar’s ability to directly immobilize Cd in soil ，a successive wheat cultivation with experiment was conducted. Three biochar with different Cd adsorption mechanisms were added into soils and a mesh bag was used to separate the soil particles (> 1 μm) from biochar. The results showed that the ash contents and anionic contents (CO 3 2- and PO 4 3- ) of the biochar decreased with the cultivation time, while the oxygen-containing functional groups content and CEC of the biochar increased. Resultly, the Cd concentration on biochar decreased, highly decreased by 68.9% for WBC300, while unstable Cd species (acid soluble and reducible fraction of Cd) on biochar increased with successive cultivation, increasing from 3% to 17% for WBC300 in FS. Correspondingly, the ability of biochar to inhibit Cd accumulation in wheat decreased. The results of this study illustrated that the ability of biochar to directly immobilize Cd in soil is not permanent, it gradually decreases with aging in soil. The adsorption mechanism of Cd on biochar changed from precipitation to complexation and ion exchange processes could be the main reason.

Farmyard Manure as K-Fertilizer Modulates Soil Biological Activities and Yield of Wheat Using the Integrated Fertilization Approach

Potassium fertilization is often ignored by assuming alluvial soils have sufficient K reserves in the North West Plain Zone of India under cereal-based cropping systems. There is scanty information on the impact of integrated K fertilization on soil enzymes, nutrients availability, microbial population, and wheat yield cultivated in the corn–wheat cropping system. The current study exhibits that treatment (T7) applied with a dose of 90 kg K ha−1 [30 kg K by farmyard manure (FYM) and 60 kg K by muriate of potash (MOP)] significantly enhances the various microbial populations from 48.00 to 123.10% and 39.00 to 124.00%, soil enzymatic activities from 70.31 to 180.00% and 102.42 to 175.68%, and available nutrients from 2.43 to 8.44% and 14.79 to 22.87% for the first and second years of wheat cultivation, respectively. It also improved various yield parameters (12.39–41.71% and 18.24–41.14%) during both the consecutive years of cultivation. Statistical analyses revealed that the treatments (T4, T5, and T7) applied with integrated fertilization of wheat cultivation through FYM and MOP were more promising for improving soil enzymatic activities (11.59–57.22%), microbial populations (5.14–15.70%), available nutrients in soil (7.60–16.54%), and crop yield (1.06–5.85%) during the second year of cultivation as compared to the first year of cultivation. This study might be helpful to reclaim soil health and reduce chemical fertilizers used in agricultural lands.

Tillage and Plant Density as Measures of Adaptation to Climate Change

The article presents the results of research of the South-Ukrainian branch of UkrNDIPVT L. Pogoriloho on the adaptation of winter wheat cultivation technologies in grain and steam crop rotations to increase the aridity of the climate by optimizing the density of standing plants, methods and depth of basic tillage. The purpose of research is to adjust the seeding rate by changing the width of the rows when growing winter wheat, as an agro-technological measure of accumulation and rational use of soil moisture (agro-technological direction of adaptation to climate change). Determining the influence of sowing rate, with different methods of tillage, on the productivity and economic efficiency of growing winter wheat in crop rotations on non-irrigated lands of southern Ukraine. Methods and Materials: field, quantitative-weight, visual and laboratory methods. Mathematical and statistical methods were used to systematize and generalize the obtained results. Research results. It has been experimentally established that the replacement of plowing to a depth of 28-30 cm for winter wheat crops with shallow (10-12 cm) disc tillage and reduction of the sowing rate of winter wheat variety «Kherson-99» to 2.25 million pieces similar seeds per hectare, by increasing the width between rows, provided an increase in grain yield by 16.7 % in 2020 and 7.7% in 2021. The profit per 1 hectare with this technology amounted to UAH 13280,5 in 2020 and UAH 28484,9 in 2021, which is 18.4 % and 9.3 % more than similar indicators in deep plowing and 31.3 % and 8.9 % more than the classic sowing rate (4.5 million units/ha). Conclusions. The efficiency of replacing deep plowing with shallow disc loosening and reducing the sowing rate to 2.25 million units/ha in the cultivation of winter wheat Kherson-99 in grain and steam crop rotation of the South of Ukraine was confirmed. A regularity in the size of the effect of reducing the seeding rate under drier conditions of the growing season was revealed.

RESOURCE-SAVING MODELS OF SPRING WHEAT CULTIVATION TECHNOLOGIES IN THE CONDITIONS OF THE FOREST-STEPPE OF THE MIDDLE VOLGA REGION

Studies to study the effectiveness of various resource-saving models of spring wheat cultivation, which allow forming stable yields with the lowest costs, were carried out in Ulyanovsk region in a stationary field experiment in 2017-2019. The soil of the experimental site is leached chernozem, medium-sized with a humus content of 6.35 %, mobile P2O5 and K2O (according to Chirikov) – 225 and 119 mg/kg, respectively, pHsalt - 6.8, the sum of absorbed bases - 48.6 mg.-eq./100 g. The scheme of the experiment provided for the study of variants of technologies for spring wheat, differing in the main tillage, the number of operations in the technological process against the background of the use of mineral fertilizers and plant protection products: traditional technology-plowing to a depth of 23 ... 25 cm (control); resource-saving technology − non-fall processing at 23 ... 25 cm; minimum technology-without autumn main processing, sowing was carried out on treated stubble in spring. The yield of spring wheat in wet 2017 according to the traditional technology was 4.21 t/ha, according to the resource − saving one – 4.15 t/ha, according to the minimum one-4.12 t/ha, or 0.09 t/ha lower than according to the traditional one. In the dry year of 2018, the yield for the resource – saving technology was 2.72 t/ha, for the traditional one – 2.08 t/ha, for the minimum one – 2.03 t/ha, which is 0.64 and 0.69 t/ha lower than for the resource-saving one. In a moderately dry 2019, according to traditional and resource-saving technologies, the wheat yield was the same-3.39 and 3.40 t/ha, and at the minimum it was lower by 0.14 and 0.15 t/ha. The developed models of resource-saving and minimal agricultural technologies allow to preserve soil fertility, reduce costs by 3.0...5.5%, reduce the cost of grain by 2.5...8.4 %, increase the efficiency and profitability of spring wheat grain production by 65 ... 75%

Reduction of Nitrogen Losses in Winter Wheat Grown on Light Soils

Two 16-year-old series of experiments with winter wheat grown in rotation after winter oilseed rape were used in the study. The experiments were located in the cold temperate dry and moist climate zones on light soils. Wheat was fertilized with nitrogen in the doses of 40, 80, 120, 160, and 200 kg N·ha−1 per year. Through the several years of the experiment, critical N rates for maximum yield and gross margin from the linear-plus plateau regressions were 149 ± 23.9 and 112 ± 23.6 kg N·ha−1, respectively. The estimated nitrogen indicators for these doses were as follows: nitrogen use efficiency (NUE) 93 and 108%, N surplus (Ns) 6.8 and −10.1 kg·N·ha−1, yield-scaled Ns, N2O, and NH3 3.5 and −0.2; 0.35 and 0.30; 0.31 and 0.25 kg N·Mg−1, respectively. Experiments have shown that two strategies for reducing nitrogen losses on light soils under wheat cultivation are possible: by limiting the N dose to the critical values due to the yield requirements, or due to the gross margin. The analysis of the 11-year data for 2300 farm fields with winter wheat grown on light soils showed that only 10% of them were implementing the first strategy, and as much as 90% chose the second strategy.

Long-term straw returning improve soil K balance and potassium supplying ability under rice and wheat cultivation

The aims of the present study were to provide scientific bases for rational use of crop straw to substitute chemical potassium (K) input. The effects of potassium fertilization and straw incorporation on soil K balance and K supplying in a long-term (14 years) field experiment. Five treatments were examined: (1) no fertilization (CK); (2) mineral fertilizing (NPK); (3) straw 6000 kg h m−2 (S); (4) NPK with straw 3000 kg h m−2 (NPK1/2S); and (5) NPK with straw 6000 kg h m−2 (NPKS). K composition, K balance and quantity-intensity (Q/I) relationship were studied. Under no fertilization or low straw returned conditions, soil K was unbalanced and deficienct seriously. Straw return at 6000 kg h m−2 per season with fertilization improved the soil potassium supply and K balance. Long-term K surplus (4 or 5 years), compared with NPK, the NPKS significantly increased non-special K adsorption (Knsa) and non-exchangeable K (Kne) by 5.7–11.2 mg kg−1 and 65.7–128.1 mg kg−1, respectively. Q/I relationship showed cropping without straw K or without fertilizer K resulted in lower quantity (nonspecifically and specifically held K i.e. – ∆K0 and Kx) and intensity (equilibrium activity ratio i.e. CR0K) of K in tested soils. K-fertilization with straw maintain higher exchangeable K (EK0) and a higher difference between EK0 and minimum exchangeable K(EKmin), and would help to prevent depletion in non-exchangeable pool of soil K under intensive cropping. Additionally, The straw return mainly decreased potential buffering capacity for exchangeable pool (PBCKn), 43.92–48.22% of added K in soil might be converted to exchangeable pool while it was 25.67–29.19% be converted to non-exchangeable pool. The contribution of exchangeable K towards plant K uptake would be higher in the soil with straw than the soil without straw and the non-exchangeable K would be the long-term fixed K as a supplement to the potassium pool. K fertilizer with 6000 kg h m−2 straw return in each crop season increased soil available K and slowly available K. The findings underlined importance of the straw return and contribution for sustain K supplying ability of soils.

Global cultivation of wheat crops induces considerable shifts in the range and niche of species relative to their wild progenitors

Species’ range and niche play key roles in understanding ecological and biogeographical patterns, especially in projecting global biotic homogenization and potential distribution patterns of species under global change scenarios. However, few studies have investigated the ability of crop cultivation to influence potential range sizes and niche shifts of species. Wheat and its wild progenitors share the same origin and evolutionary history, and thus provide an excellent system to explore this topic. Using ensembled ecological niche models and niche dynamic models, we studied the potential range sizes of wheat and its wild progenitors, as well as their niche dynamics. Our results showed that wheat had larger range size and niche breadth than its wild progenitors, suggesting that wheat cultivation is a more powerful driver of range and niche expansion than natural niche evolution. Additionally, wheat and its wild progenitors occupied different niche positions, and the former did not conserve the niches inherited from the latter, implying that wheat cultivation considerably induces niche shifts. The niche dynamics between wheat and its wild progenitors were not only closely associated with cultivation but were also modified by the niche conservatism of its wild progenitors. In contrast to most invasive plants, wheat, as a global staple crop species, did not conserve the niche space inherited from its wild progenitors, suggesting that compared with most plant invasions, cultivation may have a stronger effect on niche shifts. Therefore, global niche shifts induced by crop cultivation need much more attention, though the underlying mechanisms require further study.

Productivity, quality and efficiency of spring durum wheat cultivation when treating crops with a biological product

The production experiments were carried out based on the farm “Yaroslav the Wise” of the Starooskol district of the Belgorod region. The article studies the effect of the biological product Biogor KM during the pre-sowing treatment of grain in combination with double spraying of growing plants of spring durum wheat Dar Chernozemya 2. One of the experiments provides for grain processing with the period of “germination-ripening” of its wheat plants reduced by 8 days. The second variant, in addition to processing the grain, had two sprayings carried out during the growing season. The second experiment lasted even less by 12 days in comparison with the control variant. The article establishes the positive influence of the biological product on the formation of the productivity structure of spring durum wheat plants. Grain processing in combination with spraying during the growing season led to the formation of the best productivity structure: plant height was 39% higher, the number of spikelets was 41.8% higher, the number of spikelets was higher by 35.3%, and the grain weight per spike was 39.2%. versus the control variant. The yield in the experiment was in direct proportion to the method of application of the biological product and the conditions of the growing season. The largest increase in yield - 0.40 t / ha or 14.5% was obtained in the variant with grain processing in combination with double spraying of plants during the growing season, the average yield for the studied period was 3.14 t / ha and was maximum, indicators of economic and bioenergy efficiency was also the best.

Fungi Inhabiting the Wheat Endosphere

Wheat production is influenced by changing environmental conditions, including climatic conditions, which results in the changing composition of microorganisms interacting with this cereal. The group of these microorganisms includes not only endophytic fungi associated with the wheat endosphere, both pathogenic and symbiotic, but also those with yet unrecognized functions and consequences for wheat. This paper reviews the literature in the context of the general characteristics of endophytic fungi inhabiting the internal tissues of wheat. In addition, the importance of epigenetic regulation in wheat–fungus interactions is recognized and the current state of knowledge is demonstrated. The possibilities of using symbiotic endophytic fungi in modern agronomy and wheat cultivation are also proposed. The fact that the current understanding of fungal endophytes in wheat is based on a rather small set of experimental conditions, including wheat genotypes, plant organs, plant tissues, plant development stage, or environmental conditions, is recognized. In addition, most of the research to date has been based on culture-dependent methods that exclude biotrophic and slow-growing species and favor the detection of fast-growing fungi. Additionally, only a few reports of studies on the entire wheat microbiome using high-throughput sequencing techniques exist. Conducting comprehensive research on the mycobiome of the endosphere of wheat, mainly in the context of the possibility of using this knowledge to improve the methods of wheat management, mainly the productivity and health of this cereal, is needed.