Increased Winter Wheat Research Articles

The Synergistic Production Effect of Water and Nitrogen on Winter Wheat in Southern Xinjiang.

Water and nitrogen management are crucial for food security and the efficient use of water and fertilizer, especially in arid regions. Three irrigation levels, namely, 80% crop water requirement (ETC) (W1), 100% ETC (W2), and 120% ETC (W3), and three nitrogen application levels, namely, 0 kg/ha (N1), 207 kg/ha (N2), and 276 kg/ha (N3), were used as the experimental treatments, and a control group, denoted as CK, was created. The results show that the maximum height achieved was 82.16 cm under W3N3. There was a single-peak variation trend throughout the growth stages of SPAD. It peaked at 58.44 under W3N3 and then at 27.9 under W2N2. The net photosynthetic and transpiration rates displayed bimodal peaks and the phenomenon of a "photosynthetic midday depression". And the prominent peaks in leaf water use efficiency occurred at 14:00 and 18:00, alongside noteworthy enhancements observed under the W3 treatment. Water and nitrogen and their interactions significantly affected the dry matter (DM) of winter wheat, with the spike accounting for the highest percentage. The W2N2 treatment demonstrated superior effectiveness in enhancing winter wheat water use efficiency, offering the potential to decrease irrigation requirements by 20% and nitrogen application by 25%. Moreover, the maximum PFPN attained under W2N2 reached 60.13, representing a noteworthy 35.25% increase compared to the control group (CK), but the HI of the W2N2 treatment only reached 0.56. The highest HI was achieved with W3N2 (0.73), and the nitrogen application of 207 kg/ha was more conducive to obtaining a higher HI. The highest yield was achieved under W3N3 (13.599 t/ha), followed by W2N2 (12.447 t/ha), and the spike proportion exceeded 60% with W2N2, and its production cost and economic benefit ratio of under 0.31 were superior to those for other treatments. Multiple regression analysis revealed that the maximum yield reached 12.944 t/ha with an irrigation amount of 3420.1 m3/ha and a nitrogen application of 251.92 kg/ha. Overall, our study suggests using an optimal water-nitrogen combination, specifically an irrigation level of 2829 m3/ha and a nitrogen application rate of 207 kg/ha, leading to increased winter wheat yields and economic benefits. These research results provide a pragmatic technique for improving winter wheat production in southern Xinjiang.

Effects of climactic warming on the starch and protein content of winter wheat grain under conservation tillage in the North China Plain

Climate warming is expected to affect global food security and nutritional quality, particularly winter wheat grain protein content. No-tillage (NT) agriculture may be an effective option to mitigate the effects of climate warming; however, the associated mechanism remains unclear. Therefore, this study investigated the effects of warming under NT and conventional tillage (CT) treatments on the physiological growth processes, yield, yield components, plant nitrogen metabolism, as well as grain protein content and fractions of winter wheat in the North China Plain for four consecutive years (2021–2022). The results showed that temperature increases under the NT and CT systems significantly impacted winter wheat growth and development, prolonged the effective reproductive period, and increased the leaf area index, photosynthesis rate, and aboveground dry matter mass in the pre-flowering stage. Hence, the temperature increase and tillage treatment affected the components and yield of winter wheat. The number of fruiting spikelets decreased significantly, and the number of grains and thousand-grain weight increased under the CT and NT systems. Meanwhile, the elevated temperature significantly increased the winter wheat yield by 11.4% (CT) and 62.3% (NT) compared with the control group. Temperature increases also significantly increased winter wheat seed protein content by 10.88% and 30.91% under CT and NT, respectively. The effects of warming and tillage treatments on seed protein fractions were more complex, with warming under CT reducing the albumin, globulin, and glutenin contents, whereas warming under NT increased the contents of all four protein fractions. This study provides a scientific basis for the mechanism underlying climate warming effects on protein content and fractions of winter wheat grains.

Increasing winter wheat yield and nitrogen utilization, and reducing residual soil nitrogen in semi-humid areas: A study matching deep fertilizer application with regional water scenarios

The deep fertilizer application (DF) has been recommended as an effective strategy for promoting crop growth and yield formation. However, the controversial discussion revolves on the challenge of effectively using DF to simultaneously increase crop nitrogen (N) uptake and minimize residual nitrate contents to enhance N utilization efficiency. Based on a precipitation manipulation experiment conducted during 2019–2022 in a semi-humid area, we examined how annual precipitation amount during wheat growing season (125 mm = dry year; 200 mm = normal year; 275 mm = wet year) and the soil water storage before sowing (500 mm, SWSS500; 400 mm, SWSS400; 300 mm, SWSS300) variability affected the N uptake, N utilization efficiency, yield, and residual soil nitrate content in wheat fields treated with N fertilization at different depths (conventional surface fertilization depth of 5 cm: D5; 15 cm: D15; 25 cm: D25; 35 cm: D35). A complementary field experiment was also performed under natural rainfall condition using the 15N tracer technique to quantify the fate of fertilizer-N and 15N use efficiency (15NUE). 15N analyses showed that DF (D15, D25 and D35) significantly increased 15NUE by improving wheat 15N uptake (5.8–15.3%) and reducing potential 15N loss (9.6–12.3%) compared with D5, but the residual soil 15N in the 0–1.0 m layer increased (13.2–26.3%) as the fertilization depth increased (p < 0.05). The simulated precipitation experiment showed that compared with D5, DF significantly increased wheat N uptake, N utilization efficiency and yield by 1.4–16.4%, 1.4–14.0% and 3.3–21.5%, respectively, in the dry and normal years. In the wet year, N uptake, N utilization efficiency and yield under D15 increased by 1.9–9.8%, 2.1–11.1% and 2.2–13.4% compared to other fertilization depth treatments (p < 0.05). SWSS500 and SWSS400 significantly increased the N uptake (9.8–65.0%) and yield (0.6–69.3%) under all fertilization depth treatments irrespective of the annual precipitation amount than SWSS300 (p < 0.05). DF increased the residual NO3–-N concentration (0–2.0 m soil layer) by 2.2–7.3% compared to D5 across all annual precipitation amounts and SWSS levels, and D35 increased the maximum downward movement of NO3–-N to 1.4 m under wet year within SWSS500. DF at the depth of 14–20 cm effectively improved wheat N uptake and yield as well as minimizing the residual soil NO3–-N content. Applying moderate DF can enhance sustainable wheat production with high efficiency and yields in semi-humid regions.

Combining conservation tillage with nitrogen fertilization promotes maize straw decomposition by regulating soil microbial community and enzyme activities

Straw return can effectively improve farmland soil microenvironment and fertility. However, excessive straw in the topsoil adversely affects seed germination and crop growth. At present, the characteristics and key driving factors of straw decomposition in dry farmlands are unclear. Based on the interactions between tillage practices including zero tillage (ZT), chisel tillage (CT), and plow tillage (PT) and nitrogen (N) fertilization, i.e., low N (N1, 180 kg ha-1), normal N (N2, 240 kg ha-1), and high N (N3, 300 kg ha-1), quantitative polymerase chain reaction technology and an enzymatic detection kit were used to investigate the effects of key straw C-degrading enzyme activities and microbial abundance in soil on maize straw decomposition during the growth period of winter wheat in the winter wheat/summer maize double cropping system in a dry farmland of the Loess Plateau, China. Between 2018 and 2020, ZT and CT significantly increased winter wheat yield (by 10.94% and 12.79%, respectively) and straw decomposition velocity (by 20% and 26.67%, respectively), compared with PT. Compared to N1 and N3, N2 significantly increased wheat yield (by 4.65% and 5.31%, respectively) and straw decomposition velocity (by 26.33% and 13.21%, respectively). The partial least squares pathway modelling showed significant positive direct effects of soil moisture, NO3-, NH4+, total N, bacteria, and cellulase, laccase, and xylanase activities on straw decomposition, while soil pH, fungi, and Actinomycetes had significant negative direct effects. Overall, conservation tillage (ZT and CT) combined with N2 was beneficial for straw decomposition in the drylands of the Loess Plateau and improved straw resource utilization and basic soil fertility. The results of the study clarified the key drivers of straw decomposition in dry farmlands and provided new ideas for developing updated soil management practices and adaptive N application strategies to promote the resource utilization of straw and achieve the goals of carbon peaking and carbon neutrality.

Linear dependency of winter wheat yield and nitrogen use efficiency on the pre-anthesis temperature in the lower reach of the Yangtze River

Global warming is expected to enhance the nitrogen (N) absorption capability of crops, which causes a change in nitrogen fertilizer input. However, the impacts of warming and nitrogen application on crop growth, yield and nitrogen use efficiency (NUE) are still unclear. Here, we conducted a 4-year field experiment of nighttime warming before winter wheat anthesis to explore the response of winter wheat yield to warming and the variation in nitrogen use efficiency under different nitrogen application levels (N150: 150 kg·ha−1, N225: 225 kg·ha−1, and N375: 375 kg·ha−1). The results showed that warming shortened the winter wheat vegetative growth period (VGP) by 8.3 days, while it prolonged the reproductive growth period (RGP) by 6.7 days. However, there was no significant difference in the growth period of winter wheat between nitrogen treatments. Meanwhile, warming increased winter wheat yield by increasing the number of effective spikes and grains per spike. Every 1 °C increase in pre-anthesis temperature increased winter wheat yield by 45.48, 55.78 and 60.88 g·m−2 for the N150, N225 and N375 treatments, respectively. There was no significant difference in yield between the N225 and N375 treatments, but the nitrogen partial factor productivity (PFPN) and the nitrogen utilization efficiency (NUtE) of N225 were significantly higher than those of N375. PFPN and NUtE were positively correlated with pre-anthesis air temperature under different nitrogen treatments. Multiple linear regression showed that a 1.0 °C increase enhanced NUtE by 11.62%, 9.75% and 7.85% for the N150, N225 and N375 treatments, respectively, and enhanced the PFPN by 7.77%, 8.94% and 9.81% respectively. Therefore, we suggest that 225 kg·ha−1 is an appropriate amount of nitrogen application in the lower reach of the Yangtze River under future climate warming.

Increasing Winter Wheat Grain Yield by Replicating the Management Adopted in High-Yielding Commercial Fields in Kansas during 2021–2022

Increasing Winter Wheat Grain Yield by Replicating the Management Adopted in High-Yielding Commercial Fields in Kansas during 2021–2022

Optimized border irrigation improved soil water content, increased winter wheat grain yield and water productivity

Border irrigation is still the main irrigation method in the Huang-Huai-Hai Plain of China (HPC), we aimed to find a suitable border length to reduce the quantity of irrigation water through a traditional border irrigation system to alleviate groundwater depletion. A 2-year experiment (2017–2019) was conducted with four border lengths: 20 m (L20), 30 m (L30), 40 m (L40) and 50 m (L50); supplementary irrigation was implemented during jointing and anthesis. The results showed that compared with the L20 and L30 treatments, the L40 treatment did not significantly increase the total water consumption. Compared with the L50 treatment, the L40 treatment significantly reduced the water consumption of ineffective tillers from jointing to anthesis. There was no significant difference in flag leaf net photosynthetic rate (Pn) between L40 treatment and L50 treatment at 14–28 days after anthesis, which was 12.36% and 21.31% higher than L30 and L20 treatments respectively, and significantly increased dry matter accumulation after anthesis. Grain yield were the higher in the L40 and L50 treatments, while the water productivity (WP) was highest in the L40 treatment, which was 3.98%, 4.54% and 7.94% higher than L50, L30, and L20 treatments, respectively. Hence, the irrigation field treatments with a border length of 40 m were considered the most efficient, which provides a theoretical basis for optimizing the traditional irrigation border length in HPC.

Plastic mulching significantly improves soil enzyme and microbial activities without mitigating gaseous N emissions in winter wheat-summer maize rotations

Plastic mulching is an important agricultural practice to increase crop yield by increasing soil temperature and moisture. Plastic mulching can also affect soil greenhouse gas emissions [e.g., N 2 O emissions and NH 3 volatilization] and soil characteristics such as soil enzyme and microbial activities, but the simultaneous effects of plastic mulching on these parameters and the potential links between them are rarely evaluated. Here, we conducted a field study to investigate the concurrent responses of N 2 O emissions, NH 3 volatilization, soil enzyme and microbial activities, soil dissolved organic C (DOC) and N (DON), and crop yield to plastic mulching (mulching) and no mulching (ambient) under consecutive winter wheat–summer maize rotation cycles in China’s Loess Plateau. The mulching treatment significantly increased soil water-filled pore spaces (WFPS) and soil temperature during growing cycle 1 (2018–2019 winter wheat and 2019 summer maize) and cycle 2 (2019–2020 winter wheat and 2020 summer maize). Averaged across both growing cycles, the mulching treatment significantly increased winter wheat yield by 31.8 %, summer maize yield by 36.4 %, soil NO 3 – -N content by 18.2 %, NH 4 + -N content by 27.4 %, cumulative N 2 O emissions by 34.0 % and NH 3 volatilization by 50.6 %, relative to the ambient treatment. Moreover, the mulching treatment significantly enhanced soil alkaline phosphatase, invertase, catalase, and urease activities and soil microbial biomass C and N contents in the 0–10 cm soil layer across both growing cycles. This study revealed a tradeoff, with plastic mulching significantly improving crop yields and soil enzyme and microbial activities but not mitigating N 2 O emissions or NH 3 volatilization. Our results highlight that simultaneously documenting gaseous N emissions and changes in soil properties under plastic mulching can advance the understanding of sustainable agriculture in semi-arid areas. • Soil water-filled pore spaces and soil temperatures differed highly in plastic mulching and no mulching. • Plastic mulching had higher grain yield and soil mineral N content than no mulching. • Plastic mulching significantly improved soil enzyme and microbial activities. • Plastic mulching increased NH 3 volatilization and N 2 O emissions.

Humic Acids Incorporated into Urea at Different Proportions Increased Winter Wheat Yield and Optimized Fertilizer-Nitrogen Fate

Humic acids (HAs) incorporated into urea fertilizers are highly effective at increasing yield and decreasing fertilizer-derived nitrogen (N) loss from soil, but reports of the optimal proportion in fertilizers remain widely inconsistent. In this study, we examined the effects of urea enhanced with 0.2–5.0% HAs (UHAs) on the yield, biomass production, N uptake, and N residue in fluvo-aquic soil in winter wheat cultivated over two growing seasons from 2018 to 2020 in the North China Plain. UHAs application significantly enhanced wheat grain yield, aboveground dry biomass, total and fertilizer-derived N uptake by wheat, and residue in soil, while reducing the loss of fertilizer-derived N. Additionally, UHAs treatments increased fertilizer-N residues in soil, especially in the top 30 cm soil layer, which increased with the proportion of added HAs. These positive effects were attributed to a higher spike number under UHAs treatments compared to conventional urea. Clustering analysis of the different treatments showed that 0.2% HAs were more similar to conventional urea, while 0.5% had similar effects to HAs at higher proportions. UHAs application significantly enhanced wheat grain yield, mainly via increasing spike number, and optimized the fertilizer-N fate. Among UHAs treatments, 0.5% HAs showed the highest increase in economic benefit.

Agronomic Performance of Soybean with Bradyrhizobium Inoculation in Double-Cropped Farming

Land degradation is a serious problem in arid regions, including in Central Asian countries. Soybean symbiosis with rhizobia microbes has an essential role in improving crop productivity and sustaining soil fertility in an arid environment. An experiment was conducted in light straw-colored sierozem soils in the Syrdarya region of Uzbekistan (41.4° N, 64.6° E) under arid conditions over the 2016–2017 and 2017–2018 growing seasons. This study aimed to assess the beneficial N fixation (BNF) ability of soybean in association with the Bradyrhizobium R6 strain and the Bradyrhizobium japonicum USDA110 strains and their combined effect on soil fertility and crop yield. The residues of winter wheat and soybean improved soil structure, i.e., soil humus and N and P contents, significantly differing from those on the soybean followed by summer fallow treatment. Furthermore, soybean in association with dual inoculation had the highest N derived from the atmosphere (Ndfa) (62.9 kg N ha−1), followed by individual soybean treatments with the R6 and USDA110 strains at 51.9 and 40.6 kg N ha−1, respectively. Improved soil quality positively impacted crop output, increasing winter wheat and soybean yields by 36.5% and 34.6%, respectively. Likewise, the yield parameters, i.e., the number of pods, weight of grain per pods, and 1000 seeds were significantly higher in the inoculated treatment with the highest value observed in the dual-inoculated treatment. These results suggest the insertion of soybean with symbiotic bacteria into the cropping system has considerable potential to contribute to sustainable land management practices in arid zones.

Increasing Winter Wheat Grain Yield by Replicating the Management Adopted in High-Yielding Commercial Fields

Large winter wheat yield gaps between farmer yields and yield potential in the southern Great Plains indicate the need to improve recommendations of best management strategies to profitably bridge this gap. Many studies have been completed on individual management factors pre-determined by the individual researcher, but we are not aware of studies comparing combination of practices that producers are currently using, which would be more relevant for real-world scenarios. Our objective was to determine the yield gains resulting from management intensification using combination of practices currently adopted in commercial wheat fields. Four management intensities (i.e., Low, Average, High, and Top) were derived from a survey of 656 commercial fields, and replicated in trials conducted in four and six locations in western and central Kansas. Management intensities were tested factorially on two adapted varieties. Grain yield in central Kansas ranged from 45.5 bu/a in the Low management intensity to 69.3 bu/a in the High and Top intensities, with the Average management increasing yields by 30% as compared to the Low intensity, and the High management increasing yields 18% from the Average. The variety WB4269 outyielded Zenda (63.2 and 58.7 bu/a) across central environments. In western Kansas, there was a significant variety by management interaction, where wheat yield increased from the Low and Average intensities to the High and Top intensities (72.8–78.9 to 90.7–96.0 bu/a). The WB-Grainfield and KS Dallas varieties produced similar yields in the western environments. Using similar management practices as the producers with high-yield results in central and western Kansas narrowed the yield gap, and further increases in management intensification were not warranted. Variety selection played an important role either by increasing attained yields or by interacting with management practices.

Effects of mulching on soil temperature and yield of winter wheat in the semiarid rainfed area

• Mulching significantly increased winter wheat productivity. • The cooling effect may be beneficial to vegetative growth and yield formation. • Mulching reduced the daily variable amplitude of soil temperature. • Mulching showed the warm effect in the season with lower air temperature. Mulching is a major production mode with highly effective use of water in the hydrothermal deficient area of northwest China. However, given the differences in environments and crop species among regions, it is important to further understand whether the mulching-induced changes in soil temperature are beneficial to crop production. Here, we used winter wheat to study the effect of mulching on soil temperature, soil water content, dry matter and yield. Two 3-year field experiments were conducted at two sites over 6 consecutive years (2012–2015 at site 1, and 2015–2018 at site 2) in the semiarid rainfed thermal deficient areas of northwest China. In each experiment, three mulching treatments, including straw strip mulching (SSM), plastic film mulching (PFM) and non-mulching (CK), were tested in a replicated randomized block design. Compared with CK, SSM and PFM significantly increased grain yield by 18.6–69.1 % and 35.5–61.3 % in 2012–2017 growing seasons, except that there was no significant difference in the wet year (2017–2018). In the SSM treatment, soil temperature generally decreased at different growth stages, resulting in a slight decline of 0.9–1.9 ℃ in the 0–25 cm soil layer, whereas in the PFM treatment, soil temperature increased before the jointing stage and decreased subsequently. SSM reduced the daily variable amplitude of soil temperature by decreasing the maximum soil temperature, whereas PFM produced the same effect by decreasing the maximum soil temperature and increasing the minimum soil temperature, which could promote the winter wheat vegetative growth and yield formation in the six experimental years. SSM and PFM decreased accumulated soil temperature from the overwintering stage to maturity stage by 60.1–234.6 ℃ and 30.5–148.5 ℃, respectively. The beneficial effect of the change in soil temperature in SSM and PFM plots expanded the storage capacity of winter wheat. Overall, the moderately cooling effect of mulching was conductive to promoting vegetative growth and expanding storage capacity, ultimately improving crop yield. Our results suggest that SSM can be adopted for sustainable winter wheat production in semiarid rainfed areas under thermal deficient conditions.

СТРУКТУРА ПРОДУКТИВНОСТИ ОЗИМОЙ ПШЕНИЦЫ СОРТА МОСКОВСКАЯ 39 В ЗАВИСИМОСТИ ОТ ВНЕКОРНЕВОЙ ОБРАБОТКИ БИО- И ГУМИНОВЫМИ ПРЕПАРАТАМИ

As a result of the research, the influence of biological products recommended for foliar fertilization of crops on winter wheat productivity structure in the conditions of the Republic of Mordovia was revealed. Comparison of the effectiveness of different treatment times of plants is made. The appropriate combination of application time and biological product type has been established, which has a positive effect on winter wheat productivity structure. Appropriately selected elements of cultivation technology play a significant role in increasing crop yields. Research shows that growth stimulators have a positive effect on crops, increasing their yield and grain quality. On average, over the years of our research, the maximum yield of Moskovskaya 39 winter wheat variety in OOO “Lunga” was observed on the variant with two-fold treatment of plants with Potassium Humate in autumn and spring. The increase in comparison with the control variant (without treatments with biological products) was 1.1 t / ha. All products under study significantly increased winter wheat grain yield from 11.6 to 42.6%, but this also depended on the treatment time. The maximum yield parametres were observed on the variants where the crops were double-treated: in autumn and spring. A smaller increase was noted on the variant with spring treatment of crops. In comparison with the control, the number of survived plants by the harvesting time increased by 5.8–10.4% (by 15–27 pcs / m2) under the influence of bio- and humic products; the total number of stems - by 11–74 pcs / m2 or 2.4–16.0%; the number of productive stems - by 20–85 pcs / m2 or 5.5–23.4%. The number of grains per spike in the variants treated with biological products significantly changed in comparison with the control by 1–2 pcs. The change of 1000 grain mass was 36.3–38.2 g. The smallest value was observed on the control variant, the largest - on the variant with double treatment of crops in autumn and spring with the biological product albite.

Growth and Phenology of Vulpia Myuros in Comparison with Apera Spica-Venti, Alopecurus Myosuroides and Lolium Multiflorum in Monoculture and in Winter Wheat.

Vulpia myuros has become an increasing weed problem in winter cereals in Northern Europe. However, the information about V. myuros and its behavior as an arable weed is limited. Field and greenhouse experiments were conducted in 2017/18 and 2018/19, at the Department of Agroecology in Flakkebjerg, Denmark to investigate the emergence, phenological development and growth characteristics of V. myuros in monoculture and in mixture with winter wheat, in comparison to Apera spica-venti, Alopecurus myosuroides and Lolium multiflorum. V. myuros emerged earlier than A. myosuroides and A. spica-venti but later than L. multiflorum. Significant differences in phenological development were recorded among the species. Overall phenology of V. myuros was more similar to that of L. multiflorum than to A. myosuroides and A. spica-venti. V. myuros started seed shedding earlier than A. spica-venti and L. multiflorum but later than A. myosuroides. V. myuros was more sensitive to winter wheat competition in terms of biomass production and fecundity than the other species. Using a target-neighborhood design, responses of V. myuros and A. spica-venti to the increasing density of winter wheat were quantified. At early growth stages “BBCH 26–29”, V. myuros was suppressed less than A. spica-venti by winter wheat, while opposite responses were seen at later growth stages “BBCH 39–47” and “BBCH 81–90”. No significant differences in fecundity characteristics were observed between the two species in response to increasing winter wheat density. The information on the behavior of V. myuros gathered by the current study can support the development of effective integrated weed management strategies for V. myuros.

Effects of the long‐term fertilization on pore and physicochemical characteristics of loess soil in Northwest China

AbstractLong‐term applications of inorganic and organic fertilizers have great effects on soil characteristics and crop yields. However, it is limited to quantify the influence of long‐term fertilization on soil micro‐pore structure. In this study, we investigated the effect of long‐term fertilizer application on soil pore characteristics using X‐ray computed tomography. Loess soil cores were collected from four 25‐yr fertilization treatments in Guanzhong Plain, Northwest China, including no fertilization (CK), nitrogen alone (N), nitrogen + phosphorus + potassium (NPK) and organic manure + chemical fertilizer NPK (OMNPK). The results indicated that, compared with other treatments, OMNPK treatment significantly increased winter wheat (Triticum aestivum L.) yield, total porosity, soil organic carbon and total nitrogen, and decreased soil bulk density. Notably, there is greater soil pore connectivity (EuN, Euler number) and lower fractal dimension in OMNPK than other treatments. Pore size distribution showed a significant difference with different diameters in &lt;50, 50–100, 100–1000, and &gt;1000 μm. In contrast, pore shape distribution of soil core differed little among different treatments, while elongated shape pores were appropriately 99.5% at OMNPK with more frequency than other treatments. Co‐application of organic and inorganic fertilizers improved soil pore structure and soil physical‐chemical properties, which is beneficial for preventing soil degradation.

Glyphosate-Resistant Canada Fleabane Control in Winter Wheat with Postemergence Herbicides

In recent years, there has been a rapid increase in the number of herbicide-resistant weeds, including glyphosate-resistant (GR) biotypes in Ontario, Canada. A total of six field experiments were conducted over a two-year period (2018 and 2019) to determine the control of GR Canada fleabane (Conyza canadensis (L.) Cronq.) with currently available herbicides for winter wheat in Ontario. Winter wheat was not injured with any of the herbicides evaluated. Among herbicides evaluated, pyrasulfotole/bromoxynil (preformulated), 2,4-D ester, halauxifen, fluroxypyr/halauxifen (preformulated) + MCPA, pyrasulfotole/bromoxynil/fluroxypyr (preformulated), pyrasulfotole/bromoxynil/thiencarbazone (preformulated), pyrasulfotole/bromoxynil/thiencarbazone + MCPA, and fluroxypyr/halauxifen + pyroxsulam + MCPA controlled GR Canada fleabane 94–100% at 8 weeks after application (WAA) and reduced density 95–100% and biomass 97–100%. Reduced GR Canada fleabane interference with pyrasulfotole/bromoxynil/thiencarbazone + MCPA increased winter wheat yield 27% compared to the weedy control. GR Canada fleabane interference had no adverse effect on winter wheat yield with all other treatments. Based on these results, herbicide treatments that include 2,4-D, pyrasulfotole, or halauxifen can adequately control GR Canada fleabane in winter wheat.

Strip rotary tillage with subsoiling increases winter wheat yield by alleviating leaf senescence and increasing grain filling

Sustainable agriculture in the Huang–Huai–Hai Plain of China is threatened by subsoil compaction and the decline of winter wheat productivity induced by inappropriate tillage regimes. We investigated the effects of optimizing the tillage regime on grain filling and its relationship with flag leaf senescence post-anthesis in winter wheat. Four treatments were compared: rotary tillage, strip rotary tillage, strip rotary tillage with a 2-year subsoiling interval (STS), and conventional plowing tillage. STS produced higher chlorophyll content and leaf area indexes than other treatments, resulting in a greater photosynthetically active radiation capture ratio. The net photosynthesis rate of flag leaves from 14 to 28 days after anthesis and dry matter accumulation at maturity were higher in STS than in other treatments. Sucrose content and sucrose phosphate synthase activity of flag leaves first increased and then decreased during grain filling and were highest in STS. STS increased superoxide dismutase activity, increased soluble protein content, and reduced malondialdehyde concentrations in flag leaves after the middle grain-filling stages, resulting in reduced premature senescence. This consequence extended the active grain filling period and increased grain weight. The highest yields were observed in STS, reaching 10,451 kg ha−1 in 2014–2015 and 10,074 kg ha−1 in 2015–2016, owing to increased spike numbers and 1000-kernel weight. Overall, our study suggested that STS could substantially increase photosynthetic capacity and delay leaf senescence, thus promoting grain filling rate and increasing winter wheat yields.

Efficiency of Application of Mineral Fertilizers for Winter Wheat on Leached Black Chernozem

The article considers the issue of productivity and economic efficiency of the use of slow-acting nitrogen fertilizers obtained using the ”Si” technology of winter wheat. The studies were carried out in 2014–2017 in the northern forest-steppe zone of the Tyumen region on the experimental field of the Agrotechnological Institute of the GAU of the Northern Trans-Urals. increased winter wheat grain yield. Winter wheat productivity according to the studied options on average over the years of research ranged from 3.36–3.41 t/ha, which is higher than the control about the option of 0.27–0.32 t/ha. The economic efficiency of the fertilizers used was determined by the cost of increasing the crop and the cost of obtaining it. Analysis of economic efficiency showed that when sowing the nitrogen fertilizer, urea encapsulated by Si technology (30 kg/ha d.v.) received the highest profitability – 81.68 %. The resulting conditionally net income in this option amounted to 1663.4 rub/ha. In the sixth version of the experiment (encapsulated urea according to the ”Si” technology (60 kg/ha a.v.) + KCl (30 kg/ha a.a.) + P2O5 (40 kg/ha a.a.)) profitability – 76.0 %. Obtained conditionally net income in this embodiment amounted to 1222 rubles/ha. The return on fertilizer use ranged from 4 to 85 %.

EFFECTS OF PLANTING SYSTEMS AND STRAW MULCHING ON CARBON EMISSIONS AND WINTER WHEAT GRAIN YIELD IN THE NORTH CHINA PLAIN

SUMMARYTo explore effective ways to decrease soil CO2 emission and increase winter wheat grain yield in the North China Plain, a field experiment was conducted using two planting systems (wide-precision planting and conventional-cultivation planting) and two straw mulching rates (0 and 0.6 kg m−2) to study carbon emission, carbon cumulative emission flux, grain yield and yield carbon utilization efficiency. In the 2013–2014 and 2014–2015 winter wheat growing seasons, CO2 emission rate and cumulative CO2-C fluxes following straw mulching treatment were significantly lower than those following non-mulching treatments, whereas the yield carbon utilization efficiency was significant higher following straw mulching treatment. Straw mulching significantly reduced winter wheat grain yield, which was mainly due to the significant decrease in spike numbers and 1000-kernel weight. However, wide-precision planting system significantly increased winter wheat grain yields by increasing spike numbers under straw mulching conditions. Therefore, wide-precision planting system could compensate for the reduction in winter wheat grain yield under carbon sequestration conditions in the North China Plain.

Comment on “Tillage effects on certain physical and hydraulic properties of a loamy soil under a crop rotation in a semi-arid region with a cool climate.” by Z. Gozubuyuk, U. Sahin, I. Ozturk, A. Celik, M. Cemal Adiguzel

The influence of different tillage practices (conventional tillage, reduced tillage, and no-till on bulk density, total porosity, penetration resistance, field capacity, field water content and infiltration rate) on samples of loamy soil in a semi-arid region were investigated by Gozubuyuk et al. (2014). There is need to further discuss some of the main issues raised in Gozubuyuk et al. (2014) study. One of such issues is the consideration of pore size distribution into two classes of micro-pores and macro-pores. In this paper, the basic classes of soil pores were not taken into consideration, including aeration pores/macro-pores (>30μm diameter), capillary pores/medium-pores (0.2 to 30μm diameter) and micro-pores (<0.2μm diameter), in order to discuss field capacity; especially, plant available water content. Another problem deals with the conclusion where authors stated that “the no-till system increased winter wheat germination due to higher water content”. The paper did not analyze the effective role of biological activity and plant nutrition, above all, organic input (mulch effect on temperature) effect was ignored. Therefore, it could not be concluded that the increased winter wheat germination under no-till practice is only due to higher water content. The discussion is inconsistent about the probable reasons of higher infiltration in no-tillage. Moreover, while the infiltration rate is increased under no-tillage, a problem was raised during interpretation regarding the concept of infiltration improvement, especially in a semi-arid region. This commentary elaborates on the earlier mentioned issues.