Narrowing row spacing and adding inter-block promote the grain filling and flag leaf photosynthetic rate of wheat under enlarged drip tube spacing system.

Enlarging the lateral space of drip tubes saves irrigation equipment costs (drip tubes and bypass), but it will lead to an increased risk of grain yield heterogeneity between wheat rows. Adjusting wheat row spacing is an effective cultivation measure to regulate a row's yield heterogeneity. During a 2-year field experiment, we investigated the variations in yield traits and photosynthetic physiology by utilizing two different water- and fertilizer-demanding spring wheat cultivars (NS22 and NS44) under four kinds of drip irrigation patterns with different drip tube lateral spacing and wheat row spacing [① TR4, drip tube spacing (DTS) was 60 cm, wheat row horizontal spacing (WRHS) was 15 cm; ② TR6, DTS was 90 cm, WRHS was 15 cm; ③ TR6L, DTS was 90 cm, WRHS was 10 cm, inter-block spacing (IBS) was 35 cm; and ④ TR6S, DTS was 80 cm, WRHS was 10 cm, IBS was 25 cm]. The results showed that under 15-cm equal row spacing condition, after the number of wheat rows served by a single tube increased from four (TR4, control) to six (TR6), NS22 and NS44 exhibited a marked decline in yield. The decline of NS22 (9.93%) was higher than that of NS44 (9.04%), and both cultivars also showed a greater decrease in grain weight and average grain-filling rate (AGFR) of inferior grains (NS22: 23.19%, 13.97%; NS44: 7.78%, 5.86%) than the superior grains (NS22: 10.60%, 8.33%; NS44: 4.89%, 4.62%). After the TR6 was processed to narrow WRHS (from 15 to 10 cm) and add IBS (TR6L: 35 cm; TR6S: 25 cm), the grain weight per panicle (GWP) and AGFR of superior and inferior grains in the third wheat row (RW3) of NS22 and NS44 under TR6L increased significantly by 26.05%, 8.22%, 14.05%, 10.50%, 5.09%, and 5.01%, respectively, and under TR6S, they significantly increased by 20.78%, 9.91%, 16.19%, 9.28%, 5.01%, and 4.14%, respectively. The increase in GWP and AGFR was related to the increase in flag leaf area, net photosynthetic rate, chlorophyll content, relative water content, actual photochemical efficiency of PSII, and photochemical quenching coefficient. Among TR4, TR6, TR6L, and TR6S, for both NS22 and NS44, the yield of TR6S was significantly higher than that of TR6 and TR6L. Furthermore, TR6S showed the highest economic benefit.

Drip Fertigation Enhances the Responses of Grain Yield and Quality to Nitrogen Topdressing Rate in Irrigated Winter Wheat in North China.

Conventional water and nitrogen (N) management practice in north China, comprising flood irrigation and N fertilizer broadcast (FB), limits sustainable wheat production. Drip fertigation (DF) has been widely adopted in wheat production in recent years and has effectively improved yields. However, the responses of the yield and quality to the N topdressing rate (NTR) under DF are still unclear. This study determined the responses of the wheat yield and quality to NTR under DF, as well as assessing whether DF could synergistically increase the yield and quality. A field experiment was conducted in north China for two seasons (2021-2023) using a split-plot design with three replicates. The main plot used the management practice (FB and DF) and the sub-plot had N treatment (no N applied, and NTRs of 0, 40, 80, 120, and 160 kg ha-1 with 150 kg N ha-1 as basal fertilizer, denoted as N0, T0, T40, T80, T120, and T160, respectively). Our results showed that high and saturated wheat yields (12.08 and 11.46 t ha-1) were obtained under DF at T80, and the highest yields were produced at T160 (11.71 and 11.30 t ha-1) under FB. Compared with FB, the greatest yield increase of 10.4-12.6% was achieved at T80 under DF. A higher spike number due to the increased effective stem percentage and a greater grain weight because of enhanced post-anthesis biomass production (BPpost) explained the improved yield under DF. The enhanced post-anthesis radiation use efficiency (RUE) led to the greater BPpost under DF. The enhanced specific leaf N, antioxidant capacity, and stomatal conductance under DF explained the higher light-saturated photosynthesis rate of flag leaves, which partly led to the increased post-anthesis RUE. NTR higher than 80 kg ha-1 did not enhance the yield, but it significantly improved the gliadin and glutelin contents, thereby leading to a higher total protein content, better gluten characteristics, and superior processing quality. Therefore, drip fertigation is a practical strategy for increasing both yield and quality with reduced water input and appropriate N input in irrigated winter wheat in north China. Applying 80 kg ha-1 of NTR under drip irrigation produces a high yield, but further gain in grain quality needs a higher NTR.

The Concurrent Application of Phosphogypsum and Modified Biochar as Soil Amendments Influence Sandy Soil Quality and Wheat Productivity.

Sandy soil covers a significant portion of Egypt's total land area, representing a crucial agricultural resource for future food security and economic growth. This research adopts the hypothesis of maximizing the utilization of secondary products for soil improvement to reduce ecosystem pollution. The study focuses on assessing the impact of combining phosphogypsum and modified biochar as environmentally friendly soil amendments on loamy sand soil quality parameters such as soil organic carbon, cation exchange capacity, nutrient levels, and wheat yield. The treatments were T1: the recommended NPK fertilizer (control); T2: 2.5 kg phosphogypsum m-2 soil; T3: 2.5 kg rice straw biochar m-2 soil; T4: 2.5 kg cotton stalk biochar m-2 soil; T5: 2.5 kg rice-straw-modified biochar m-2 soil; T6: 2.5 kg cotton-stalk-modified biochar m-2 soil; and T7 to T10: mixed phosphogypsum and biochar treatments. The results revealed that the combined use of phosphogypsum and modified cotton stalk biochar (T10) significantly enhanced soil organic carbon (SOC) by 73.66% and 99.46% in both seasons, the soil available N both seasons by 130.12 and 161.45%, the available P by 89.49% and 102.02%, and the available K by 39.84 and 70.45% when compared to the control treatment. Additionally, this treatment led to the highest grain yield of wheat (2.72 and 2.92 Mg ha-1), along with a significant increase in straw yield (52.69% and 59.32%) compared to the control treatment. Overall, the findings suggest that the combined use of phosphogypsum and modified biochar, particularly cotton-stalk biochar, holds promise for improving loamy sand-soil quality and wheat productivity.

Clear effects on root system architecture of winter wheat cultivars (Triticum aestivum L.) from cultivation environment and practices.

Roots play a pivotal role in the adaption of a plant to its environment, with different root traits adapting the plant to different stresses. The environment affects the Root System Architecture (RSA), but the genetic factors determine to what extent, and whether stress brought about by extreme environmental conditions is detrimental to a specific crop. This study aimed to identify differences in winter wheat RSA caused by cultivation region and practice, in the form of preceding crop (precrop), and to identify if modern cultivars used in Sweden differ in their reaction to these environments. This was undertaken using high-throughput phenotyping to assess the RSA. Clear differences in the RSA were observed between the Swedish cultivation regions, precrop treatments, and interaction of these conditions with each other and the genetics. Julius showed a large difference between cultivars, with 9.3-17.1% fewer and 12-20% narrower seminal roots. Standardized yield decreased when grown after wheat, 23% less compared to oilseed rape (OSR), and when grown in the Southern region, 14% less than the Central region. Additionally, correlations were shown between the root number, angle, and grain yield, with different root types being correlated depending on the precrop. Cultivars on the Swedish market show differences that can be adapted to the region-precrop combinations. The differences in precrop effect on RSA between regions show global implications and a need for further assessment. Correlations between RSA and yield, based on root-type × precrop, indicate different needs of the RSA depending on the management practices and show the potential for improving crop yield through targeting genotypic and environmental conditions in a holistic manner. Understanding this RSA variance, and the mechanisms of conditional response, will allow targeted cultivar breeding for specific environments, increasing plant health and food security.

Assessing the quality and grain yield of winter wheat in the organic farming management under wheat-legume intercropping practice.

Intercropping is an alternative farming method that maximizes crop yield and resource usage effectiveness, especially in low-input agricultural systems. Legume-based intercropping systems can effectively boost the quality and wheat yield by promoting soil functions and microbial activities. However, changes in the types of legumes and field management can alter the response of crop functions. A three-year field study was conducted on intercropping cultivation of winter wheat variety (Butterfly and Lorien) and legume species (faba bean, incarnate clover, spring pea, winter pea) to assess grain yield and wheat quality in organic farming. Based on the results, Butterfly showed higher grain quality but lower grain yield and yield components than Lorien. Mixtures of legume crops with winter wheat did not significantly differ in wheat grain yield, but grain quality variables were significantly affected. Protein content (PC) was significantly higher in wheat and legume mixtures than in sole wheat by 4 %. PC in wheat + winter pea (Wheat + Wi) and wheat + faba bean (Wheat + Fa) were higher than wheat sown alone. Wet gluten (WG) was higher in Wheat + Wi than in sole wheat and wheat + incarnate clover mixtures (Wheat + In). The rheological parameters evaluated by the Mixolab showed greater wheat quality in Butterfly and legume mixtures. Mixed and row-row intercropping of wheat and legume species did not significantly influence rheological properties. To conclude, customizing wheat yield and grain quality under the effect of winter wheat and legume mixtures requires considering the optimal solution based on different cultivates, wheat varieties and legume species to achieve the desired response.

Higher Seed Rates Enlarge Effects of Wide-Belt Sowing on Canopy Radiation Capture, Distribution, and Use Efficiency in Winter Wheat.

The optimized winter wheat sowing method comprising wide-belt sowing (WBS) can improve the ears number and biomass to increase the grain yield, compared with conventional narrow-drill sowing (NDS). The seed rate and the interaction between the sowing method and seed rate also affect yield formation. However, the effects of the sowing method and seed rate, as well as their interaction on biomass production, particularly the interception of solar radiation (ISR) and radiation use efficiency (RUE), are unclear. A field experiment was conducted for two seasons in southern Shanxi province, China, using a split-plot design with sowing method as the main plot (WBS and NDS) and seed rate as the sub-plot (100-700 m-2). Our results showed that while WBS had a significant and positive effect, increasing the yield by 4.7-15.4%, the mechanism differed between seed rates. Yield increase by WBS was mainly attributed to the increase in total biomass resulting from both the promoted pre- and post-anthesis biomass production, except that only the increase in post-anthesis biomass mattered at the lowest seed rate (100 m-2). The higher biomass was attributed to the increased ISR before anthesis. After anthesis, the increased ISR contributed mainly to the increased biomass at low seed rates (100 and 200 m-2). In contrast, the increased RUE, resulting from the enhanced radiation distribution within canopy and LAI, contributed to the higher post-anthesis biomass at medium and high seed rates (400 to 700 m-2). The greatest increases in total biomass, pre-anthesis ISR, and post-anthesis RUE by WBS were all achieved at 500 seed m-2, thereby obtaining the highest yield. In summary, WBS enhanced grain yield by increasing ISR before anthesis and improving RUE after anthesis, and adopting relatively higher seed rates (400-500 m-2) was necessary for maximizing the positive effect of WBS, and thus the higher wheat yield.

High- or Low-Yielding F2 Progeny of Wheat Is Result of Specific TaCKX Gene Coexpression Patterns in Association with Grain Yield in Paternal Parent.

Members of the TaCKX gene family (GFM) encode oxidase/dehydrogenase cytokinin degrading enzymes (CKX), which play an important role in the homeostasis of phytohormones, affecting wheat development and productivity. Therefore, the objective of this investigation was to test how the expression patterns of the yield-related TaCKX genes and TaNAC2-5A (NAC2) measured in 7 days after pollination (DAP) spikes and the seedling roots of parents are inherited to apply this knowledge in the breeding process. The expression patterns of these genes were compared between parents and their F2 progeny in crosses of one mother with different paterns of awnless cultivars and reciprocal crosses of awned and awnless lines. We showed that most of the genes tested in the 7 DAP spikes and seedling roots of the F2 progeny showed paternal expression patterns in crosses of awnless cultivars as well as reciprocal crosses of awned and awnless lines. Consequently, the values of grain yield in the F2 progeny were similar to the pater; however, the values of seedling root mass were similar to the mother or both parents. The correlation analysis of TaCKX GFMs and NAC2 in spikes and spikes per seedling roots reveals that the genes correlate with each other specifically with the pater and the F2 progeny or the mother and the F2 progeny, which shape phenotypic traits. The numbers of spikes and semi-empty spikes are mainly correlated with the specific coexpression of the TaCKX and NAC2 genes expressed in spikes or spikes per roots of the pater and F2 progeny. Variable regression analysis of grain yield and root mass with TaCKX GFMs and NAC2 expressed in the tested tissues of five crosses revealed a significant dependency of these parameters on the mother and F2 and/or the pater and F2 progeny. We showed that the inheritance of yield-related traits depends on the specific cooperative expression of some TaCKX GFMs, in some crosses coupled with NAC2, and is strongly dependent on the genotypes used for the crosses. Indications for parental selection in the breeding of high-yielding lines are discussed.

A framework for assessing the impacts of land-use/cover change and climate change on wheat productivity under 1.5 and 2.0 °C warming at watershed scale.

BACKGROUND: Irrigation is used extensively to enhance grain production and ensure food security. Many studies have used crop models and global climate models to study the variation of irrigated crop yield in the context of climate change. But most considered the influence of direct climate change but neglected the influence of irrigation water availability, which is affected by land-use/cover change (LUCC) and indirect climate change, on irrigated crop yield. This study therefore developed a framework including Patch-generating Land Use Simulation model, Soil and Water Assessment Tool, Agricultural Production Systems sImulator Model, and global climate models for exploring the impacts of LUCC, direct climate change, and indirect climate change on wheat yield in a typical watershed. RESULTS: Both LUCC and climate change caused increased runoff from October to May, and thus increased the irrigation water availability, by 51.6 and 30.7 mm per growing season under 1.5 and 2.0 °C warming, respectively. The combined influence of LUCC, direct, and indirect climate change increased wheat yield by about 18.5% and 15.5% in the context of 1.5 and 2.0 °C warming, respectively. The relative contribution of LUCC, indirect climate change and direct climate change to yield was 4.7%, 41.2%, and 54.1% under 1.5 °C warming, and 13.1%, 28.7%, and 58.2% under 2.0 °C warming, respectively. CONCLUSION: We suggest that changes in irrigation water availability should be considered from a watershed perspective when simulating the influence of climate change on crop yield, especially regional crop production estimation. © 2023 Society of Chemical Industry.

Effects of Biochar Applied in Either Rice or Wheat Seasons on the Production and Quality of Wheat and Nutrient Status in Paddy Profiles.

In a rice-wheat rotation system, biochar (BC) applied in different crop seasons undergoes contrast property changes in the soil. However, it is unclear how aged BC affects the production and quality of wheat and the nutrent status in a soil profile. In the present soil column experiment, the effects of no nitrogen (N) fertilizer and BC addition (control), N fertilizer (N420) and BC (5 t ha-1) applied at rice [N420 + BC(R)], or wheat [N420 + BC(W)] seasons at a same rate of N fertilizer (420 kg ha-1 yr-1) on yield and quality of wheat as well as the nutrient contents of soil profiles (0-5, 5-10, 10-20, 20-30, 30-40, and 40-50 cm) were observed. The results showed that N420 + BC(W) significantly reduced NH4+-N content in 5-10 and 10-20 cm soils by 62.1% and 36.2%, respectively, compared with N420. In addition, N420 + BC(W) significantly reduced NO3--N contents by 17.8% and 40.4% in 0-5 and 20-30 cm profiles, respectively, but N420 + BC(R) slightly increased them. The BC applied in wheat season significantly increased the 0-5 and 40-50 cm soil total N contents (24.0% and 48.1%), and enhanced the 30-40 and 40-50 cm soil-available phosphorus contents (48.2 and 35.75%) as well as improved the 10-20 and 20-30 cm soil-available potassium content (38.1% and 57.5%). Overall, our results suggest that N420 + BC(W) had stronger improving effects on soil fertility than N420 + BC(R). Compared to N420, there was a significant 5.9% increase in wheat grain yield, but no change in total amino acids in wheat kernels in N420 + BC(W). Considering the responses of soil profile nutrient contents as well as wheat yield and quality to BC application in different crop seasons, it is more appropriate to apply BC in wheat season. Our results could provide a scientific basis for the ideal time to amend BC into the rice-wheat rotation system, in order to achieve more benefits of BC on crop production and soil fertility.

Enhancing wheat production and quality in alkaline soil: a study on the effectiveness of foliar and soil applied zinc.

Cultivation of high-yield varieties and unbalanced fertilization have induced micronutrient deficiency in soils worldwide. Zinc (Zn) is an essential nutrient for plant growth and its deficiency is most common in alkaline and calcareous soils. Therefore, this study aimed to evaluate the effect of Zn applied either alone or in combination with foliar application on the quality and production of wheat grown in alkaline soils. Zn was applied in the form of zinc sulfate (ZnSo4) to the soil and as a foliar spray during the sowing and tillering stages, respectively. Results showed that Zn fertilization of wheat, irrespective of modes of application, significantly increased grain and biological yield, grain per spike, and 1,000 grains weight over control; however, its effect was more noticeable when applied as 7.5 kg ha-1 of soil Zn combined with foliar Zn at 2.5 kg ha-1. Zn application significantly increased the grain protein content from 9.40% in the control to a maximum of 11.83% at soil Zn of 10 kg ha-1. Similarly, Zn application improved Zn, phosphorus (P), and potassium (K) concentrations in wheat grains. Moreover, correlation analysis showed that the grain Zn concentration was positively correlated with the grain P concentration. The correlation between P concentration in wheat grains and 1,000 grain weight was not significant. A total of 1,000 grains weight was positively correlated with tillers per plant, grain yield, and biological yield. There were positive correlations between protein content, biological yield, grain yield, and tillers per plant. Therefore, soil-applied Zn + foliar application in alkaline soils with limited Zn availability is crucial for improving wheat yield and grain quality.

Global evaluation of key factors influencing nitrogen fertilization efficiency in wheat: a recent meta-analysis (2000-2022).

Improving nitrogen use efficiency (NUE) without compromising yield remains a crucial agroecological challenge in theory and practice. Some meta-analyses conducted in recent years investigated the impact of nitrogen (N) fertilizer on crop yield and gaseous emissions, but most are region-specific and focused on N sources and application methods. However, various factors affecting yield and N fertilizer efficiency in wheat crops on a global scale are not extensively studied, thus highlighting the need for a comprehensive meta-analysis. Using 109 peer-reviewed research studies (published between 2000 and 2022) from 156 experimental sites (covering 36.8, 38.6 and 24.6% of coarse, medium, and fine texture soils, respectively), we conducted a global meta-analysis to elucidate suitable N management practices and the key factors influencing N fertilization efficiency in wheat as a function of yield and recovery efficiency and also explained future perspectives for efficient N management in wheat crop. Overall, N fertilization had a significant impact on wheat yield. A curvilinear relationship was found between N rates and grain yield, whereas maximum yield improvement was illustrated at 150-300 kg N ha-1. In addition, N increased yield by 92.18% under direct soil incorporation, 87.55% under combined chemical and organic fertilizers application, and 72.86% under split application. Site-specific covariates (climatic conditions and soil properties) had a pronounced impact on N fertilization efficiency. A significantly higher yield response was observed in regions with MAP > 800 mm, and where MAT remained < 15 °C. Additionally, the highest yield response was observed with initial AN, AP and AK concentrations at < 20, < 10 and 100-150 mg kg-1, respectively, and yield response considerably declined with increasing these threshold values. Nevertheless, regression analysis revealed a declining trend in N recovery efficiency (REN) and the addition of N in already fertile soils may affect plant uptake and RE. Global REN in wheat remained at 49.78% and followed a negative trend with the further increase of N supply and improvement in soil properties. Finally, an advanced N management approach such as "root zone targeted fertilization" is suggested to reduce fertilizer application rate and save time and labor costs while achieving high yield and NUE.

Selenium-Containing Organic Fertilizer Application Affects Yield, Quality, and Distribution of Selenium in Wheat.

This study was designed to investigate the effect on wheat yield of applying organic fertilizers (OF) with five different selenium (Se) concentrations. The mineral nutrients, cadmium (Cd) content, and the distribution of Se in wheat plants were also measured. The results showed that wheat yields reached a maximum of 9979.78 kg ha-1 in Mengcheng (MC) County and 8868.97 kg ha-1 in Dingyuan (DY) County, Anhui Province, China when the application amount of selenium-containing organic fertilizer (SOF) was up to 600 kg ha-1. Among the six mineral nutrients measured, only the calcium (Ca) content of the grains significantly increased with an increase in the application amount of SOF in the two regions under study. Cd content showed antagonistic effects with the Se content of wheat grains, and when the SOF was applied at 1200 kg ha-1, the Cd content of the grains was significantly reduced by 30.1% in MC and 67.3% in DY, compared with under the Se0 treatment. After application of SOF, the Se content of different parts of the wheat plant ranked root > grain > spike-stalk > glume > leaf > stem. In summary, SOF application at a suitable concentration could increase wheat yields and significantly promote the Ca content of the grains. Meanwhile, the addition of Se effectively inhibited the level of toxic Cd in the wheat grains.

Moderate organic fertilizer substitution for partial chemical fertilizer improved soil microbial carbon source utilization and bacterial community composition in rain-fed wheat fields: current year.

Organic fertilizers can partially replace chemical fertilizers to improve agricultural production and reduce negative environmental impacts. To study the effect of organic fertilizer on soil microbial carbon source utilization and bacterial community composition in the field of rain-fed wheat, we conducted a field experiment from 2016 to 2017 in a completely randomized block design with four treatments: the control with 100% NPK compound fertilizer (N: P2O5: K2O = 20:10:10) of 750 kg/ha (CK), a combination of 60% NPK compound fertilizer with organic fertilizer of 150 kg/ha (FO1), 300 kg/ha (FO2), and 450 kg/ha (FO3), respectively. We investigated the yield, soil property, the utilization of 31 carbon sources by soil microbes, soil bacterial community composition, and function prediction at the maturation stage. The results showed that (1) compared with CK, organic fertilizer substitution treatments improved ear number per hectare (13%-26%), grain numbers per spike (8%-14%), 1000-grain weight (7%-9%), and yield (3%-7%). Organic fertilizer substitution treatments increased the total nitrogen, available nitrogen, available phosphorus, and soil organic matter contents by 26%, 102%, 12%, and 26%, respectively, compared with CK treatments. Organic fertilizer substitution treatments significantly advanced the partial productivity of fertilizers. (2) Carbohydrates and amino acids were found to be the most sensitive carbon sources for soil microorganisms in different treatments. Particularly for FO3 treatment, the utilization of ß-Methyl D-Glucoside, L-Asparagine acid, and glycogen by soil microorganisms was higher than other treatments and positively correlated with soil nutrients and wheat yield. (3) Compared with CK, organic fertilizer substitution treatments increased the relative abundance of Proteobacteria, Acidobacteria, and Gemmatimonadetes and decreased the relative abundance of Actinobacteria and Firmicutes. Interestingly, FO3 treatment improved the relative abundance of Nitrosovibrio, Kaistobacter, Balneimonas, Skermanella, Pseudomonas, and Burkholderia belonging to Proteobacteria and significantly boosted the relative abundance of function gene K02433 [the aspartyl-tRNA (Asn)/glutamyl-tRNA (Gln)]. Based on the abovementioned findings, we suggest FO3 as the most appropriate organic substitution method in rain-fed wheat fields.

Peanut-based Rotation Stabilized Diazotrophic Communities and Increased Subsequent Wheat Yield.

The introduction of legumes into rotations can improve nitrogen use efficiency and crop yield; however, its microbial mechanism involved remains unclear. This study aimed to explore the temporal impact of peanut introduction on microorganisms related to nitrogen metabolism in rotation systems. In this study, the dynamics of diazotrophic communities in two crop seasons and wheat yields of two rotation systems: winter wheat - summer maize (WM) and spring peanut → winter wheat - summer maize (PWM) in the North China Plain were investigated. Our results showed that peanut introduction increased wheat yield and biomass by 11.6% (p < 0.05) and 8.9%, respectively. Lower Chao1 and Shannon indexes of the diazotrophic communities were detected in soils that sampling in June compared with those sampling in September, although no difference was found between WM and PWM. Principal co-ordinates analysis (PCoA) showed that rotation system significantly changed the diazotrophic community structures (PERMANOVA; p < 0.05). Compared with WM, the genera of Azotobacter, Skermanella, Azohydromonas, Rhodomicrobium, Azospirillum, Unclassified_f_Opitutaceae, and Unclassified_f_Rhodospirillaceae were significantly enriched (p < 0.05) in PWM. Furthermore, rotation system and sampling time significantly influenced soil properties, which significantly correlated with the top 15 genera in relative abundance. Partial least squares path modeling (PLS-PM) analysis further showed that the diazotrophic community diversity (alpha- and beta-diversity) and soil properties (pH, SOC and TN) significantly affected wheat yield. In conclusion, legume inclusion has the potential to stabilize diazotrophic community structure at the temporal scales and increase subsequent crop yield.

Achieving high yield and nitrogen agronomic efficiency by coupling wheat varieties with soil fertility.

Wheat breeding has progressively increased yield potential through decades of selection, markedly increased the capacity for food production. Nitrogen (N) fertilizer is essential for wheat production and N agronomic efficiency (NAE) is commonly index used for evaluate the effects of N fertilizer on crop yield, calculated as the difference of wheat yield between N fertilizer treatment and non-N fertilizer treatment divided by the total N application rate. However, the impact of variety on NAE and its interaction with soil fertility remain unknown. Here, to clarify whether and how wheat variety contributes to NAE, and to determine if soil conditions should be considered in variety selection, we conduct a large-scale analysis of data from 12,925 field trials spanning ten years and including 229 wheat varieties, 5 N fertilizer treatments, and a range of soil fertility across China's major wheat production zones. The national average NAE was 9.57 kg kg-1, but significantly differed across regions. At both the national and regional scales, variety significantly affected NAE, and different varieties showed high variability in their performance among low, moderate, and high fertility soils. Here, superior varieties with both high yield and high NAE were identified at each soil fertility fields. The comprehensive effect of selecting regionally superior varieties, optimizing N management, and improving soil fertility could potentially decrease the yield gap by 67 %. Therefore, variety selection based on soil conditions could facilitate improved food security while reducing fertilizer inputs to alleviate environmental impacts.

Seed priming with essential oils for sustainable wheat agriculture in semi-arid region.

Drought is one of the major constraints to global crop production. A number of sustainable systems have focused on the development of environmentally friendly innovative biotechnological interventions to prevent yield losses. The use of essential oils as a seed priming agent can make an important contribution as a natural stimulant in increasing drought stress tolerance. This study focuses on the effects of seeds coated with different doses (D0 (0%), D1 (0.01%), D2 (0.05%), D3 (0.10%) and D4 (0.25%)) of sage, rosemary and lavender essential oils on wheat germination, seedling establishment and yield parameters. Turkey's local wheat genotype Köse was used as plant material. The impact of the seed priming on germination rate, coleoptile length, shoot length, root length, shoot fresh and dry weight, root fresh and dry weight, relative water content (RWC), proline, and chlorophyll contents was assessed in laboratory experiments. In addition, the effect of essential oil types on yield parameters and agronomic components (plant height, spike height, number of grains per spike, grain yield per spike, grain yield per unit area, thousand-grain weight) was evaluated in a field experiment during the 2019-2020 crop seasons in a semi-arid climate. According to laboratory results, the highest germination rate among all treatment doses was determined in the D2 treatment (rosemary 93.30%, sage 94.00% and lavender 92.50%), while the lowest germination rates for all essential oil types were determined in the D4 treatment (rosemary 41.70%, sage 40.90% and lavender 40.90%). Increasing treatment doses showed a similar suppressive effect on the other parameters. In the field experiment, the highest grain yield (256.52 kg/da) and thousand-grain weight (43.30 g) were determined in the rosemary treatment. However, the priming treatment has an insignificant on the number of grains per spike and the spike length. The light of these results, the effects of essential oil types and doses on yield parameters were discussed. The findings highlight the importance of using essential oils in seed priming methods for sustainable agricultural practices.

Matching N supply for yield maximization in salt-affected wheat agri-food systems: On-farm participatory assessment and validation.

Driven by the UN-SDGs of achieving food security and agricultural sustainability, it remains more challenging in degraded ecosystems to simultaneously improve the crop performance without creating unintended favour for excessive fertilization and associated environmental consequences. We assessed the N-use pattern of 105 wheat-growers in sodicity affected Ghaghar Basin of Haryana, India, and then experimented upon to optimize and identify indicators of efficient N use in contrasting wheat cultivars for sustainable production. The survey results revealed that majority of farmers (88%) have increased their reliance on N nutrition (∼18 % extra N), and even extended their duration of N scheduling (12-15 days) for better plant adaptation and yield insurance in sodicity stressed wheat; albeit to a greater extent in moderately sodic soils applying 192 kg N ha-1 in 62 days. The participatory trials validated the farmers' perception of using more than the recommended N in sodic lands. This could realize the transformative improvements in plant physiological [higher photosynthetic rate (Pn; 5 %) and transpiration rate (E; 9 %)] and yield [more tillers (ET; 3 %), grains spike-1 (GS; 6 %) and healthier grains (TGW; 3 %)] traits culminating in ∼20 % higher yield at 200 kg N ha-1 (N200). However, further incremental N application had no apparent yield advantage or monetary benefits. At N200, every additional kilogram of N captured by the crop beyond the recommended N improved grain yields by 36.1 kg ha-1 in KRL 210 and 33.7 kg ha-1 in HD 2967. Further, the varietal differences for N requirements, with 173 kg ha-1 in KRL 210 and 188 kg ha-1 in HD 2967, warrants the need of applying balanced fertilizer dose and advocate revision of existing N recommendations to cope up the sodicity induced agricultural vulnerability. Principal Component Analysis (PCA) and correlation matrix showed N uptake efficiency (NUpE) and total N uptake (TNUP) as the highly weighted variables illustrating strong positive association with grain yield, and potentially deciding the fate of proper N utilization in sodicity stressed wheat. Key insights suggested that combining participatory research with farmers' knowledge and local perspective could be decisive in better integration of technologies, and serving to adapt the real-time soil sodicity stress and sustaining wheat yields with economized farm profits.

Containment of Fusarium culmorum and Its Mycotoxins in Various Biological Systems by Antagonistic Trichoderma and Clonostachys Strains.

Prevention of fungal diseases caused by Fusarium species, including F. culmorum, and thus the accumulation of mycotoxins in wheat ears, is a constant challenge focused on the development of new, effective crop management solutions. One of the currently most ecologically attractive approaches is biological control using natural antagonistic microorganisms. With this in mind, the antagonistic potential of thirty-three Clonostachys and Trichoderma strains was assessed in this work. Screening tests were carried out in in vitro cultures, and the observed potential of selected Trichoderma and Clonostachys strains was verified in field and semi-field experiments with two forms of wheat: winter cv. Legenda and spring cv. Bombona. Three strains, namely C. rosea AN291, T. atroviride AN240 and T. viride AN430 were reported to be most effective in inhibiting the growth of F. culmorum KF846 and the synthesis of DON, 3AcDON and ZEN under both laboratory and semi-controlled field conditions. Observations of the contact zones of the tested fungi in dual cultures exposed their mycoparasitic abilities against KF846. In addition, studies on liquid cultures have demonstrated the ability of these strains to eliminate F. culmorum toxins. Meanwhile, the strains of T. atroviride AN35 and T. cremeum AN392 used as soil inoculants in the field experiment showed a different effect on the content of toxins in ears (grains and chaffs), while improved wheat yield parameters, mainly grain health in both wheat cultivars. It is concluded that the selected Trichoderma and Clonostachys strains have a high potential to reduce the adverse effects of F. culmorum ear infection; therefore, they can be further considered in the context of potential biocontrol factors and as wheat crop improvers.

Biocontrol and plant growth promotion by combined Bacillus spp. inoculation affecting pathogen and AMF communities in the wheat rhizosphere at low salt stress conditions.

Applying plant growth-promoting rhizobacteria (PGPR) improves the efficiency of soil-borne disease control and is considered a sustainable practice. However, the effect of PGPR on the fungal community, especially pathogenic fungi and arbuscular mycorrhizal fungi (AMF), remains unclear. In this study, we examined the effects of a compound microbial agent (consisting of Bacillus subtilis HG-15 and Bacillus velezensis JC-K3) on the incidence and yield of wheat under low salt stress, as well as compared the diversity and community composition of the rhizosphere fungal and AMF communities of wheat in the CK (not inoculated bacterial agent) and BIO (inoculated with a bacterial agent) groups. Chlorophyll relative content (SPAD), net photosynthesis rate (Pn), transpiration rate (Tr), leaf water use efficiency (WUE L), grains per spike and wheat yield in the BIO group increased more than in the CK group. The number of diseased plants and disease incidence was observed to be reduced. The relative efficacy reached 79.80%. We classified 1007 fungal operational taxonomic units (OTU) based on Miseq sequencing data: 11 phyla, 173 families, 319 genera, and 521 species. Fifty-four OTUs were classified from the AMF effective sequences, including 1 phylum, 3 families, 3 genera, and 17 species. The inoculation of bacterial agents reduced the relative abundance of pathogen genera such as Gibberella, Fusarium, Cladosporium, and Alternaria in wheat rhizosphere. It increased the relative abundance of AMF species such as Glomus-group-B-Glomus-lamellosu-VTX00193, Glomus-viscosum-VTX00063, and Glomus-Glo2-VTX00280. In addition, pH, EC, exchangeable K, available N, total N, organic matter, and olsen P were the main driving forces for shaping wheat rhizosphere fungi. The pH value was positively correlated with the relative abundance of fungal communities in soil, especially Gibberella, Cladosporium, Fusarium, and Alternaria. In summary, inoculation with Bacillus subtilis HG-15 and Bacillus velezensis JC-K3 affected wheat yield, incidence, rhizosphere soil chemical properties, rhizosphere fungi, and AMF fungal diversity and community. The findings may provide a theoretical foundation and strain support for constructing efficient PGPR-community and clarifying its mechanism of pathogenic bacteria inhibition.

Identification of beneficial Lebanese Trichoderma spp. wheat endophytes.

Wheat is one of the most important crops in the world. Its production can be influenced by a diversity of beneficial and pathogenic rhizospheric microbes, including fungi. Amongst them, beneficial Trichoderma spp. can be used as alternatives to chemical fertilizers, as they are cheap and harmless to the environment. Our study aimed to isolate, identify, and characterize Trichoderma spp. from Lebanon associated with wheat. Two Trichoderma strains belonging to T. afroharzianum, and T. guizhouense species, were isolated and found to be endophytes, enhancing root growth and producing Indole-3-acetic acid. Inoculation also improved seedling development, and increased plant growth and yield. Furthermore, the two strains inhibit Fusarium growth in vitro. These Trichoderma spp. have thus the capacity to be used as organic fertilizers for wheat.