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Trichothecenes are sesquiterpenoid toxins produced by diverse ascomycetes, including Fusarium. The trichothecene analog deoxynivalenol (DON) produced by the Fusarium head blight (FHB) pathogen Fusarium graminearum is a virulence factor on wheat and a major food and feed safety concern. In Fusarium, the trichothecene biosynthetic gene (TRI) cluster consists of 7–14 genes. Most TRI cluster genes are conserved and their specific roles in trichothecene biosynthesis have been determined. An exception is TRI14, which is not required for DON synthesis in vitro but is required for spread of F. graminearum in wheat heads. In the current study, gene expression analyses revealed that TRI14 was highly induced in infected wheat heads. We demonstrated that TRI14 was not only required for F. graminearum spread but also important for initial infection in wheat. Although a prior study did not detect DON in infected seeds, our analyses showed significantly less DON and fungal biomass in TRI14-mutant (designated ∆tri14)-inoculated heads than wild-type-inoculated heads. Gene expression comparison showed that the level of expression of TRI genes was similar in the wheat tissues infected with ∆tri14 or the wild type, indicating the reduced toxin levels caused by ∆tri14 may be due to less fungal growth. ∆tri14 also caused less lesion and grew less in wheat coleoptiles than the wild type. The growth of ∆tri14 in carboxymethylcellulose medium was more sensitive to hydrogen peroxide than the wild type. The data suggest that TRI14 plays a critical role in F. graminearum growth, and potentially protects the fungus from plant defense compounds. [ABSTRACT FROM AUTHOR]

Summary: How plants distribute biomass among organs influences resource acquisition, reproduction and plant–plant interactions, and is essential in understanding plant ecology, evolution, and yield production in agriculture. However, the genetic mechanisms regulating allocation responses to the environment are largely unknown.We studied recombinant lines of wheat (Triticum spp.) grown as single plants under sunlight and simulated canopy shade to investigate genotype‐by‐environment interactions in biomass allocation to the leaves, stems, spikes, and grains. Size‐corrected mass fractions and allometric slopes were employed to dissect allocation responses to light limitation and plant size.Size adjustments revealed light‐responsive alleles associated with adaptation to the crop environment. Combined with an allometric approach, we demonstrated that polymorphism in the DELLA protein is associated with the response to shade and size. While a gibberellin‐sensitive allelic effect on stem allocation was amplified when plants were shaded, size‐dependent effects of this allele drive allocation to reproduction, suggesting that the ontogenetic trajectory of the plant affects the consequences of shade responses for allocation.Our approach provides a basis for exploring the genetic determinants underlying investment strategies in the face of different resource constraints and will be useful in predicting social behaviours of individuals in a crop community. [ABSTRACT FROM AUTHOR]

The intermittent ozone (O3) exposure of crops to alternating high and low concentrations is common in fields, but its impact on crop production has not been thoroughly investigated. In this study, two widely planted and O3-sensitive crops, winter wheat and soybean, were intermittently exposed to elevated O3 concentrations in open-top chambers. The results showed that the winter wheat and soybean yields significantly decreased with O3 exposure (AOT40, cumulative hourly O3 concentration above 40 ppb) (p < 0.001). The relative yield losses were 0.99% per AOT40 for winter wheat and 1.2% per AOT40 for soybean, respectively. The responses of the crop biomasses to elevated O3 concentrations were lower than that of crop yield. Although the O3-induced crop yield and biomass losses under continuous O3 exposure were greater than those under intermittent O3 exposure, the differences were not statistically significant. Therefore, we can conclude that the effects of elevated O3 concentrations on crops are closely related to the exposure dose but not significantly related to the temporal distribution of elevated O3 concentrations. This study improves our understanding of how crop production responds to intermittent O3 exposure. [ABSTRACT FROM AUTHOR]

Climate change‐induced drought stress (DS) poses a significant threat to crop production, emphasizing the need for innovative strategies to mitigate its adverse effects. Prior studies have demonstrated the distinct capacities of salicylic acid (SA) and sodium hydrosulfide (NaHS) to augment plant resilience against drought‐related stressors. However, little is known about how they work together or the specific processes by which they increase DS tolerance. The purpose of this research was to determine how SA and NaHS affected the performance of wheat plants during the growing seasons of 2021–2022 and 2022–2023, when there was a drought. The research employed a block‐randomized experimental layout with split plots, where the primary factors included two irrigation levels: full irrigation (IW1, 100% of water requirement) and deficit irrigation (IW2, 50% of water requirement). Secondary factors included the application of mock control, 0.5 mM SA, and 0.3 mM NaHS, an H2S donor, either individually or in combination, administered before the onset of DS. The application of SA, NaHS, or their combination significantly enhanced wheat plant resistance to DS. Significant increases in a number of physiological markers, including proline content, relative water content (RWC), Fv/Fm, chlorophyll content, and antioxidant enzyme activity, demonstrated this improvement. Furthermore, in drought‐stressed wheat plants, SA and NaHS treatments decreased the amounts of hydrogen peroxide (H2O2), malondialdehyde (MDA) content, and electrolyte leakage (EL). In conclusion, our study highlights the possibility of SA and NaHS, whether applied individually or in combination, to improve drought resistance in wheat plants, presenting a viable approach to lessen the effects of climate change on agricultural yield. [ABSTRACT FROM AUTHOR]

Soil sodicity is a major constraint to seedling emergence and crop production, potentially reducing plant growth due to physical and chemical constraints. Studying responses to ion imbalances may help identify genotypes tolerant to chemical constraints in sodic soils, thereby improving productivity. We evaluated the performance of four wheat (Triticum aestivum L.) genotypes in solutions with five sodium adsorption ratios (SARs) ranging from 0 to 60. For all four genotypes, seedling emergence and shoot dry matter (DM) decreased significantly with increasing SARs. A significant positive correlation was observed between Ca concentration in roots as well as both root and shoot DM for all genotypes. At SAR values > 20, the more tolerant genotype (EGA Gregory) displayed higher Ca concentrations in root tissues, whereas the more sensitive genotype (Baxter) exhibited Na-induced Ca deficiency. Thus, the selection of genotypes that are able to accumulate Ca in roots in sodic conditions may be a useful trait for selecting genotypes tolerant of soils with high ESP values. However, for soils that restrict plant growth at ESP (SAR) values of 6–10%, it is likely that growth is restricted by physical constraints rather than by a Na-induced Ca deficiency. [ABSTRACT FROM AUTHOR]

Several biogeochemical models have been applied to understand the potential effects of management practices on soil organic carbon (SOC) sequestration, crop growth, and yield. In this study, the denitrification and decomposition (DNDC) model was used to simulate soil SOC dynamics and harvested C-biomass in rice–wheat rotation under organic/inorganic fertilization with conventional tillage (CT) and reduced tillage (RT). Before calibration, DNDC underpredicted harvestable grain C-biomass of rice where percent difference (PD) varied from 29.22% to 42.14%, and over-simulated grain C-biomass of wheat where PD was −55.01% with 50% nitrogen–phosphorus–potassium (NPK) and 50% animal manure applied under the CT treatment. However, after calibration by adjusting default values of soil and crop parameters, DNDC simulated harvestable grain C-biomass of both crops very close to observed values (e.g., average PD ranged from −2.81% to −6.17%). DNDC also predicted the effects of nutrient management practices on grain C-biomass of rice/wheat under CT/RT using d-index (0.76 to 0.96) and the calculated root mean squared error (RMSE of 165.36 to 494.18 kg C ha−1). DNDC simulated SOC trends for rice–wheat using measured values of several statistical indices. Regression analysis between modeled and observed SOC dynamics was significant with R2 ranging from 0.35 to 0.46 (p < 0.01), and intercept ranging from 0.30 to 1.34 (p < 0.65). DNDC demonstrated that combined inorganic and organic fertilization may result in higher C-biomass and more SOC sequestration in rice–wheat systems. [ABSTRACT FROM AUTHOR]

Selecting cultivars with greater biomass results in higher yields and greater carbon sequestration. Storage of atmospheric carbon in the plant/soil pool contributes not only to food security but also to mitigating climate change and other agroecological benefits. The objective of this study was to determine: (1) grain, residue, and root biomass yields; (2) harvest indexes; (3) residue-to-product ratio; (4) root-to-shoot ratio; (5) biomass carbon and nitrogen contents; and (6) C:N ratios for two new and two old winter wheat cultivars. The greatest yield difference was found between old Srpanjka (the lowest) and new Kraljica (the highest) cultivar where grain, residue, root, and total biomass yield was higher by 38%, 91%, 71%, and 64%, respectively. Total biomass was composed of 40–47% grain, 10–11% roots, 32–36% stems + leaves, 9–11% chaff, and 1–2% spindle. The range of HI was 0.45–0.53, RPR 0.91–1.25, and R:S ratio 0.12–0.13. For all cultivars, positive carbon and negative nitrogen balance within the plant pool was determined. Still, root biomass and rhizodeposition carbon remain open questions for a better understanding of agroecosystems' C dynamics. [ABSTRACT FROM AUTHOR]

Increasing biomass allocation to the root system may increase soil-organic carbon stocks and confer drought adaptation in water-limited environments. Understanding the genetic bases and inheritance of biomass allocation is fundamental for drought tolerance breeding and soil health. The objective of this study was to determine the general and specific combining ability, maternal effects and the mode of gene action controlling the major yield and biomass allocation related traits in wheat to identify good combiners for breeding and enhanced carbon sequestration. Ten selected wheat genotypes were crossed in a full diallel mating design, and 90 F2 families were generated and evaluated in the field and greenhouse under drought-stressed and non-stressed conditions. Significant differences were recorded among the tested families revealing substantial variation for plant height (PH), kernels per spike (KPS), root biomass (RB), shoot biomass (SB), total plant biomass (PB) and grain yield (GY). Additive gene effects conditioned PH, SB, PB and GY under drought, suggesting the polygenic inheritance for drought tolerance. Strong maternal and reciprocal genetic effects were recorded for RB across the testing sites under drought-stressed conditions. Line BW162 had high yield and biomass production and can be used to transfer favourable genes to its progeny. The parental line LM75 maintained the general combining ability (GCA) effects in a positive and desirable direction for SB, PB and GY. Early generation selection using PH, SB, PB and GY will improve drought tolerance by exploiting additive gene action under drought conditions. Higher RB production may be maintained by a positive selection of male and female parents to capture the significant maternal and reciprocal effects found in this study. [ABSTRACT FROM AUTHOR]

Phosphorus (P) management in wheat grown under saline soil conditions requires a better understanding of how P placement and salt stress affect spatial root distribution, plant agronomic performance, and nutrient utilization. A column culture experiment was conducted with two wheat genotypes, Alice and LX99, five P placements ('Top Dressed High P', TopHP; 'Top Dressed Reduced P', TopRP; 'Deep Banded High P', DeepHP; 'Deep Banded Reduced P', DeepRP; and 'No P added', −P), and two salt stress levels ('salt stress', +S; 'non-salt stress', −S) to investigate differences in biomass accumulation, nutrient utilization, and root distribution (0–20 cm, 20–40 cm, and 40–100 cm) among treatments. Deep P placement under non-salt stress increased root distribution at 20–40 cm soil depth for both genotypes compared to top P placement. P application under salt stress increased root weight at all three soil depths in both genotypes and P accumulation in aboveground plant parts (except for LX99 under TopRP). The highest P utilization efficiency occurred in Alice with TopRP and in LX99 with DeepRP under non-salt and salt stresses. Overall, a coordinated adaptation in allocating biomass between belowground and aboveground plant parts, along with altered nutrient utilization, was necessary to reach a growth compromise in response to P supply changes and salinity. Therefore, genotype, P placement depth, and soil salinity should be considered to improve wheat P utilization efficiency under saline conditions. [ABSTRACT FROM AUTHOR]

The effect of methyl jasmonate (MJ) (1 µM) on wheat (Triticum aestivum L. cv. Moskovskaya 39), seedlings and the fatty acid (FA) content of leaves under optimal and cadmium (Cd) (100 µM) stress conditions wasinvestigated. Height and biomass accumulation was studied traditionally; the netphotosynthesis rate (Pn) was studied using a photosynthesis system, FAs'profile—GS-MS. No effect on the height and Pn rate of the MJ pre-treatment wheat at optimum growth conditions was found. MJ pre-treatment led to a decrease in the total amount of saturated (about 11%) and unsaturated (about 17%) identified FAs, except α-linoleic FA (ALA), which is probably associated with its involvement in energy-dependent processes. Under Cd impact, the MJ-treated plants had a higher biomass accumulation and Pn rate compared to untreated seedlings. Both MJ and Cd caused stress-induced elevation of palmitic acid (PA) versus an absence of myristic acid (MA), which is used for elongation. It is suggested that PA participates in alternative adaptation mechanisms (not only as a constituent of the lipid bilayer of biomembrane) of plants under stress. Overall, the dynamics of FAs showed an increase in the saturated FA that is important in the packing of the biomembrane. It is supposed that the positive effect of MJ is associated with lower Cd content in plants and a higher ALA content in leaves. [ABSTRACT FROM AUTHOR]

AquaCrop is one of the dynamic and user-friendly models for simulating different conditions governing plant growth in the field. But this model requires many input parameters such as plant information, soil, climate, groundwater, and management factors. In this research, to solve this problem and develop a model with fewer input data, artificial neural network (ANN), support vector regression (SVR), and combined support vector regression with firefly algorithm (SVR-FFA) were used. For this purpose, 440 scenarios were created in 2 farms located in Iran, and the values of yield and biomass obtained by the AquaCrop model were compared with intelligent models. Also, consumable seed and irrigation were considered as inputs of intelligent models. The 99WestW2 farm in Miandoab had a seed yield of 6.588 t/ha, and the WestW10 farm in Mahabad had a seed yield of 5.05 t/ha. The results of this research showed that for both 99WestW2 and WestW10 farms, the SVR-FFA3 model was able to have the lowest amount of error so that for the amount of grain yield, the error values ​​for the farms were 0.033 and 0.069 t/ha, respectively. The error value of biomass was obtained for farms as 0.057 and 0.066 t/ha respectively. After SVR-FFA model, SVR and ANN models also showed good performance due to proper accuracy and saving time. Finally, SVR-FFA, SVR, and ANN models were able to predict yield and biomass values in the shortest time and with the highest accuracy with only two inputs. [ABSTRACT FROM AUTHOR]

In India, 700 million tons of agricultural waste generated annually is burned by farmers in the fields, which decreases biological activity in soil. The issue of handling the enormous amounts of crop residues that emerge from increased crop output might be resolved by composting. However, different crop residues improve soil physico-chemical and biological properties in different ways. Crop residue incorporation and fertilization (NPK) impact crop productivity due to changes in soil microbial biomass carbon, nitrogen, phosphorous, and the soil enzymatic activity. A field experiment was conducted for two years (2020–2021 and 2021–2022), which comprises five partially composted crop residues treatments viz., control, clusterbean straw, groundnut shell, pearlmillet husk, and sesame stover (added at rate of 5 t ha−1), and four fertilization (NPK) treatments viz., control, 75% RDF, 100% RDF, and 125% RDF. The microbial biomass carbon (MBC), microbial biomass nitrogen (MBN), microbial biomass phosphorus (MBP), enzymatic activities in soil and wheat yield were studied under a semi-arid environment (India). Data showed that the continuous application of crop residues and fertilizer significantly affected MBC, MBN, MBP, and soil enzymatic activity after two years of experimentation in a semi-arid region environment. The highest levels of microbial biomass (viz, MBC, MBN, MBP) and enzyme activities were noticed in the sesame stover and 125% recommended dose of fertilizer (RDF) treatments. Therefore, this study highlights the need for restoring crop residue for effective soil management. The crop residue and NPK fertilization are more efficient in improving the soil's microbial properties and the yield of wheat. [ABSTRACT FROM AUTHOR]

Winter wheat production is threatened by drought stress under rainfed conditions; thus, screening high- and stable-yielding wheat varieties to ensure the sustainable development of wheat production and food security in the Huang-Huai-Hai Plain (HHHP) is vital. In this research, four-year field experiments with twelve winter wheat varieties were conducted during the winter wheat-growing seasons between 2016 and 2020 in order to: (1) screen high- and stable-yielding winter wheat varieties under rainfed conditions, (2) investigate the mechanism of high-yielding wheat yield formation and the relationships among grain-yield formation traits, and (3) investigate the nitrogen utilization efficiency (NUtE) of high-yielding wheat. The results showed that high-yield level wheat varieties (HL; Yannong999, Taimai1918 and Yannong173) obtained a higher average grain yield than medium-yield level wheat varieties (ML) and low-yield level wheat varieties (LL) by 10.1% and 29.0%, respectively. Compared with ML and LL, HL had a higher biomass at anthesis, higher spike dry matter at anthesis, higher spike partitioning index and fruiting efficiency (grain set per unit of spike dry weight at anthesis), and the highest grain number per square meter (24.2 × 103 m−2). Simultaneously, HL maintained a higher leaf area index (LAI) at anthesis and a higher net photosynthesis rate (Pn) of flag leaves after anthesis, which contributed to a higher post-anthesis biomass; HL also had higher maturity biomass, harvest index (HI), and biomass remobilization in comparison to ML and LL. The above results demonstrated that HL improved grain yield by increasing grain number per square meter, post-anthesis biomass, biomass remobilization, maturity biomass, and HI. Additionally, HL also obtained higher NUtE by improving grain yield. Therefore, screening winter wheat varieties with traits such as HL can help achieve high and stable yields and high NUtE under rainfed conditions. [ABSTRACT FROM AUTHOR]

Source traits are currently of great interest for the enhancement of yield potential; for example, much effort is being expended to find ways of modifying photosynthesis. However, photosynthesis is but one component of crop regulation, so sink activities and the coordination of diverse processes throughout the crop must be considered in an integrated, systems approach. A set of 'wiring diagrams' has been devised as a visual tool to integrate the interactions of component processes at different stages of wheat development. They enable the roles of chloroplast, leaf, and whole-canopy processes to be seen in the context of sink development and crop growth as a whole. In this review, we dissect source traits both anatomically (foliar and non-foliar) and temporally (pre- and post-anthesis), and consider the evidence for their regulation at local and whole-plant/crop levels. We consider how the formation of a canopy creates challenges (self-occlusion) and opportunities (dynamic photosynthesis) for components of photosynthesis. Lastly, we discuss the regulation of source activity by feedback regulation. The review is written in the framework of the wiring diagrams which, as integrated descriptors of traits underpinning grain yield, are designed to provide a potential workspace for breeders and other crop scientists that, along with high-throughput and precision phenotyping data, genetics, and bioinformatics, will help build future dynamic models of trait and gene interactions to achieve yield gains in wheat and other field crops. [ABSTRACT FROM AUTHOR]

Development of low-nitrogen (N) tolerant and N-responsive durum wheat genotypes is required since nitrogen efficiency has emerged as a highly desirable trait from economic and environmental perspectives. Two hundred durum wheat genotypes were evaluated at three locations under optimum (ON) and low (LN) nitrogen conditions to screen genotypes for low-nitrogen tolerance and responsiveness to an optimum N supply. The results showed significant variations among the durum wheat genotypes for low-N tolerance and responsiveness. The average reduction in grain yield under the LN condition was 48.03% across genotypes. Only 17% of the genotypes tested performed well (grain yield reduction <40%) under LN conditions. Based on the absolute grain yield, biomass yield, and normalized difference vegetative index value, on average, 32, 14, 17, and 37% of the tested genotypes were classified as efficient and responsive, efficient and nonresponsive, inefficient and responsive, and inefficient and nonresponsive, respectively. Considering the absolute and relative grain yield, biomass yield, normalized difference vegetative index values, and stress tolerance indices as selection criteria, 17 genotypes were chosen for subsequent breeding. Among the screening indices, geometric mean productivity, stress tolerance index, yield index, and stress susceptibility index exhibited positive and significant correlations with grain yield under both N conditions; hence, either of these traits can be used to select low-N-tolerant genotypes. The common genotypes identified as LN-tolerant and responsive to N application in this study could be used as parental donors for developing N-efficient and responsive durum wheat varieties. [ABSTRACT FROM AUTHOR]

Successfully evaluating and improving the salt tolerance of genotypes requires an appropriate analysis tool to allow simultaneous analysis of multiple traits and to facilitate the ranking of genotypes across different growth stages and salinity levels. In this study, we evaluate the salt tolerance of 56 recombinant inbred lines (RILs) in the presence of salt-tolerant and salt-sensitive control genotypes using multivariate analysis of plant dry weight, measured at 75 (PDW-75) and 90 (PDW-90) days from sowing, biological yield (BY), grain yield (GY), and their salt tolerance indices (STIs). All RILs and genotypes were evaluated under the control and 15 dS m−1 for two consecutive years (2019/2020 and 2020/2021). Results showed significant main effects of salinity and genotype as well as their interactions on four plant traits. Significant genotypic differences were also found for all calculated STIs. STIs exhibited moderate to strong relationships with the four plant traits when measured under either the control or salinity conditions and between each other. The principal component analysis (PCA) showed that the most variation among all analyzed variables was explained by the first two PCs, with the PC1 and PC2 explained at 61.8–71.8% and at 28.0–38.2% of the total variation, respectively. The PC1 had positive and strong correlations with the four plant traits measured under salinity conditions and STI, YI, REI, SWPI, MRPI, MPI, GMPI, and HMPI. The PC2 had strong correlations with BY and GY measured under the control conditions and SSI, TOL, RSE, and YSI. The PC1 was able to identify the salt-tolerant genotypes, while the PC2 was able to isolate the salt-sensitive ones. Cluster analysis based on multiple traits organized 64 genotypes into four groups varied from salt-tolerant to salt-sensitive genotypes, with the salt-tolerant group attaining higher value for plant traits under salinity conditions and the STIs related to the PC1. In conclusion, the use of multivariate analysis together with the STIs that evaluated the performance of genotypes under contrasting environmental conditions will help breeders to distinguish salt-tolerant genotypes from salt-sensitive ones, even at the early growth stages of plant development. [ABSTRACT FROM AUTHOR]

Straw is a by-product from cereal cultivation. Using straw surplus as a biofuel is a popular means of its management. However, before being used for fuel purposes, straw can be successfully used as a sorbent. The present study investigated the sorption properties of wheat straw (Triticum aestivum L.) modified with ammonia water and epichlorohydrin against the reactive dye Reactive Black 5 (RB5). The tested sorbents were characterized based on FTIR, elemental analysis (C/N content), and pHPZC. The scope of the research included, among others, research on the effect of pH (pH 2–11) on the RB5 sorption efficiency, research on sorption kinetics, and determination of the maximum sorption capacity of the tested sorbents. The sorption efficiency of RB5 on the tested sorbents was the highest at pH 2–3. The experimental data from the research on the sorption kinetics of RB5 were best described by a pseudo-second-order model. The introduction of primary amine groups to the structure of sorbents significantly increased their sorption capacity towards RB5. The obtained sorption capacity of the aminated straw and the aminated straw pre-activated with epichlorohydrin was 24.12 mg RB5/g and 91.04 mg RB5/g, respectively, and it was higher by 44.3% and 444.5% compared to the unmodified straw. [ABSTRACT FROM AUTHOR]

Selenium (Se) biofortification by seed treatments has been poorly explored in wheat due to the difficulties in establishing seed treatments without compromising plant productive traits. We investigated the effects of Se seed soaking as a pre-sowing treatment in bread wheat. Five soaking periods and six Se concentrations were assessed on germination and seedling traits and compared to unsoaked seeds. Twelve hours of soaking was found beneficial for most tested Se concentrations. Then, we evaluated the effects of untreated, 0, 2.5 and 25 mM Se in 12 h seed soaking treatments along the wheat crop cycle under water-deficit (WD) and well-watered (WW) conditions in a pot experiment. Our results evidenced that 12 h of 2.5 mM Se soaking did not affect the germination percentage, and speed-up seedling emergence resulted in a considerable Se seed uptake. These plants also displayed enhanced antioxidant capacity and vegetative biomass accumulation, especially under WD. The treatment with 25 mM of Se negatively affected aerial biomass, suggesting potential toxicity. Physiological responses of Se-treated plants remained unchanged, as well as grain traits. Altogether, we propose that 12 h soaking with 2.5 mM Se is a promissory pre-sowing approach to enrich bread wheat grain and straw, particularly under water-limited environments. [ABSTRACT FROM AUTHOR]

The rapid and nondestructive determination of wheat aboveground biomass (AGB) is important for accurate and efficient agricultural management. In this study, we established a novel hybrid model, known as extreme gradient boosting (XGBoost) optimization using the grasshopper optimization algorithm (GOA-XGB), which could accurately determine an ideal combination of vegetation indices (VIs) for simulating wheat AGB. Five multispectral bands of the unmanned aerial vehicle platform and 56 types of VIs obtained based on the five bands were used to drive the new model. The GOA-XGB model was compared with many state-of-the-art models, for example, multiple linear regression (MLR), multilayer perceptron (MLP), gradient boosting decision tree (GBDT), Gaussian process regression (GPR), random forest (RF), support vector machine (SVM), XGBoost, SVM optimization by particle swarm optimization (PSO), SVM optimization by the whale optimization algorithm (WOA), SVM optimization by the GOA (GOA-SVM), XGBoost optimization by PSO, XGBoost optimization by the WOA. The results demonstrated that MLR and GOA-MLR models had poor prediction accuracy for AGB, and the accuracy did not significantly improve when input factors were more than three. Among single-factor-driven machine learning (ML) models, the GPR model had the highest accuracy, followed by the XGBoost model. When the input combinations of multispectral bands and VIs were used, the GOA-XGB model (having 37 input factors) had the highest accuracy, with RMSE = 0.232 kg m−2, R2 = 0.847, MAE = 0.178 kg m−2, and NRMSE = 0.127. When the XGBoost feature selection was used to reduce the input factors to 16, the model accuracy improved further to RMSE = 0.226 kg m−2, R2 = 0.855, MAE = 0.172 kg m−2, and NRMSE = 0.123. Based on the developed model, the average AGB of the plot was 1.49 ± 0.34 kg. [ABSTRACT FROM AUTHOR]

Genetic diversity is invaluable in developing climate-smart and drought-adapted wheat varieties. The aim of this study was to determine the extent of genetic variation present in wheat germplasm collections for biomass allocation and drought tolerance based on complementary phenotypic and root attributes and high-density single nucleotide polymorphism (SNP) markers to select breeding parents. A total of 97 bread wheat (Triticum aestivum L.) genotypes were evaluated in field and greenhouse trials under drought-stressed and non-stressed conditions. The molecular variance analysis showed that the intrapopulation variance was very high at 99%, with a small minimal inter-population variance (1%). The genetic distance, polymorphic information content and expected heterozygosity were 0.20–0.88, 0.24–1.00 and 0.29–0.58, respectively. The cluster analysis based on SNP data showed that 44% and 28% of the assessed genotypes maintained their genetic groups when compared to hierarchical clusters under drought-stressed and non-stressed phenotypic data, respectively. The joint analysis using genotypic and phenotypic data resolved three heterotic groups and allowed the selection of genotypes BW140, BW152, BW157, BW162, LM30, LM47, LM48, LM52, LM54 and LM70. The selected genotypes were the most genetically divergent with high root biomass and grain yield and are recommended for production or breeding. [ABSTRACT FROM AUTHOR]

Simple Summary: Nitrogen is one of the most important elements for plant growth and development. However, irrational fertilization causes many environmental problems: high rates of nitrogen fertilizers change the soil pH, encourage nitrate and nitrite accumulation in plants and the soil, leached nitrogen compounds cause water eutrophication and drinking water contamination, and gaseous losses of nitrogen contribute to global warming. The biological nitrogen fixation (BNF) process, in which atmospheric nitrogen is converted to ammonia by microorganisms, has a significant role in the global nitrogen cycle and agriculture. Nitrogen-fixing-bacteria inoculants could help to reduce the losses of consistently rising prices of mineral fertilizers and help to implement green revolution strategies. In this research, we found the bacteria strain Paenibacillus sp. MVY-024 that has a positive impact on nitrogen accumulation in spring wheat and was easily applied on an industrial scale. In this study, thirteen isolates, which were possibly expected to fix nitrogen, were isolated from soil and pea root nodules and identified by the gene analysis of 16S rDNA sequences. Two of these isolates that were able to form endospores and grow on nitrogen-free media were selected for spring wheat development research. The isolate Paenibacillus sp. S7 identified as Paenibacillus polymyxa was found to significantly increase the amount of ammonium and mineral N amounts in the soil. Furthermore, increased nitrogen accumulation in grains and a chlorophyll index were obtained after wheat treatment. Paenibacillus sp. S7 isolate was selected for further studies and the accession number MT900581 and strain name MVY-024 in NCBI nucleotide bank for this isolate were assigned. During the cultivation of Paenibacillus sp. MVY-024, sugarcane molasses and a yeast extract were determined as the most suitable carbon and nitrogen sources, whose optimal concentrations were 100 g L−1 and 10 g L−1, respectively. The optimal pH range for the cell culture was between 6.5 and 7.0, and the optimal air flow rate was 0.4 vvm. It was found that the air flow has an effect on biomass production and endospore formation. After Paenibacillus sp. MVY-024 biomass cultivation optimization, the cultured cell number was, on average, 2.2 × 109 cfu m L−1. [ABSTRACT FROM AUTHOR]

Six cycles of recurrent selection for early shoot vigour in wheat resulted in significant increases in leaf width and shoot biomass. Here, in replicated controlled-environment studies, the effect of early shoot vigour on root biomass, rhizosheath size, root hair length, and cell size in the roots and leaves was examined across different cycles of selection. Increased shoot vigour was associated with greater root biomass, larger rhizosheath size, and longer root hairs. Our findings demonstrate that rhizosheath size was a reliable surrogate for root hair length in this germplasm. Examination of the root epidermis revealed that the 'cell body' of the trichoblasts (hair-forming cells) and the atrichoblasts (non-hair-forming cells) decreased in size as shoot vigour increased. Therefore, in higher vigour germplasm, longer root hairs emerged from smaller trichoblasts so that total trichoblast volume (root hair plus cell body) was generally similar regardless of shoot vigour. Similarly, the sizes of the four main cell types on the leaf epidermis became progressively smaller as shoot vigour increased, which also increased stomatal density. The relationship between shoot vigour and root traits is considered, and the potential contribution of below-ground root traits to performance and competitiveness of high vigour germplasm is discussed. [ABSTRACT FROM AUTHOR]

The growth of leaves is subject to strict time regulation. Several genes influencing leaf growth have been identified, but little is known about how genes regulate the orderly initiation and growth of leaves. Here, we demonstrate that TaKLU/TaCYP78A5 contributes to a time regulation mechanism in leaves from initiation to expansion. TaKLU encodes the cytochrome P450 CYP78A5, and its homolog AtKLU has been described whose deletion is detrimental to organ growth. Our results show that TaKLU overexpression increases leaf size and biomass by altering the time of leaf initiation and expansion. TaKLU-overexpressing plants have larger leaves with more cells. Further dynamic observations indicate that enlarged wheat leaves have experienced a longer expansion time. Different from AtKLU inactivation increases leaf number and initiation rates, TaKLU overexpression only smooths the fluctuations of leaf initiation rates by adjusting the initiation time of local leaves, without affecting the overall leaf number and initiation rates. In addition, complementary analyses suggest TaKLU is functionally conserved with AtKLU in controlling the leaf initiation and size and may involve auxin accumulation. Our results provide a new insight into the time regulation mechanisms of leaf growth in wheat. [ABSTRACT FROM AUTHOR]

The large-scale industrial use of polysaccharides to obtain energy is one of the most discussed subjects in science. However, modern concepts of biorefinery have promoted the diversification of the use of these polymers in several bioproducts incorporating concepts of sustainability and the circular economy. This work summarizes the major sources of agro-industrial residues, physico-chemical properties, and recent application trends of cellulose, chitin, hyaluronic acid, inulin, and pectin. These macromolecules were selected due to their industrial importance and valuable functional and biological applications that have aroused market interests, such as for the production of medicines, cosmetics, and sustainable packaging. Estimations of global industrial residue production based on major crop data from the United States Department of Agriculture were performed for cellulose content from maize, rice, and wheat, showing that these residues may contain up to 18%, 44%, and 35% of cellulose and 45%, 22%, and 22% of hemicellulose, respectively. The United States (~32%), China (~20%), and the European Union (~18%) are the main countries producing cellulose and hemicellulose-rich residues from maize, rice, and wheat crops, respectively. Pectin and inulin are commonly obtained from fruit (~30%) and vegetable (~28%) residues, while chitin and hyaluronic acid are primarily found in animal waste, e.g., seafood (~3%) and poultry (~4%). [ABSTRACT FROM AUTHOR]

In order to realize the rapid and non-destructive monitoring of wheat biomass, field wheat trials were conducted based on different densities, nitrogen fertilizers and varieties, and unmanned aerial vehicle (UAV) was used to obtain RGB images in the pre-wintering stage, jointing stage, booting stage and flowering stage of wheat. The color and texture feature indices of wheat were obtained using image processing, and wheat biomass was obtained by manual field sampling in the same period. Then the relationship between different color and texture feature indices and wheat biomass was analyzed to select the suitable feature index for wheat biomass estimation. The results showed that there was a high correlation between image color index and wheat biomass in different stages, the values of r were between 0.463 and 0.911 (P<0.05). However, the correlation between image texture feature index and wheat biomass was poor, only 5 index values reached significant or extremely significant correlation level. Based on the above results, the color indices with the highest correlation to wheat biomass or the combining indices of color and texture features in different growth stages were used to construct estimation model of wheat biomass. The models were validated using independently measured biomass data, and the correlation between simulated and measured values reached the extremely significant level (P<0.01), and root mean square error (RMSE) was smaller. The R2 of color index model in the four stages were 0.538, 0.631, 0.708 and 0.464, and RMSE were 27.88, 516.99, 868.26 and 1539.81 kg/ha, respectively. The R2 of the model combined with color and texture index were 0.571, 0.658, 0.753 and 0.515, and RMSE were 25.49, 443.20, 816.25 and 1396.97 kg/ha, respectively. This indicated that the estimated results using the models were reliable and accurate. It also showed that the estimation models of wheat biomass combined with color and texture feature indices of UAV images were better than the single color index models. [ABSTRACT FROM AUTHOR]

Warming nights are correlated with declining wheat growth and yield. As a key determinant of plant biomass, respiration consumes O2 as it produces ATP and releases CO2 and is typically reduced under warming to maintain metabolic efficiency. We compared the response of respiratory O2 and CO2 flux to multiple night and day warming treatments in wheat leaves and roots, using one commercial (Mace) and one breeding cultivar grown in controlled environments. We also examined the effect of night warming and a day heatwave on the capacity of the ATP-uncoupled alternative oxidase (AOX) pathway. Under warm nights, plant biomass fell, respiratory CO2 release measured at a common temperature was unchanged (indicating higher rates of CO2 release at prevailing growth temperature), respiratory O2 consumption at a common temperature declined, and AOX pathway capacity increased. The uncoupling of CO2 and O2 exchange and enhanced AOX pathway capacity suggest a reduction in plant energy demand under warm nights (lower O2 consumption), alongside higher rates of CO2 release under prevailing growth temperature (due to a lack of down-regulation of respiratory CO2 release). Less efficient ATP synthesis, teamed with sustained CO2 flux, could thus be driving observed biomass declines under warm nights. [ABSTRACT FROM AUTHOR]

The study evaluated the variation of some physiological indices and productivity elements in wheat, in response to treatments with biodynamic preparations. Two preparations were used, applied singly and in combination, at the recommended dose (P500 and P501) or at half the dose (P500/2; P501/2), in five experimental variants (V1 - P5001; V2 - P500/2; V3 - P500; V4 - P500+P501; V5 - P500+P501/2). A control variant with untreated plants V6(Ct) was used for comparison. Plant height (PH, cm), biomass weight (BW, g) and grain number on ear (GNE, No) were evaluated. Plant height (PH) values ranged from 49 to 69 ±1.66 cm, biomass weight (BW) relative to one plant (mean values) ranged from 3.36 to 7.50 ±0.38 g, and grains number in ear (GNE) ranged from 20 - 38 ± 1.58. The GNE variation according to BW was described by a spline model, in conditions of 00162. 0 e = . The regression analysis facilitated the obtaining of an equation that described the variation of GNE as a function of PH and BW in statistical safety conditions, R2 = 0.998, p <0.001. According to PCA, PC1 explained 97.486% of the variance, and PC1 explained 2.0343% of the variance. It was found that in the case of variant V1 (product P501) there were negative increases, which shows that administered alone the product did not have a favourable effect on wheat plants, under the study conditions. The highest values of the increase in indices and the elements taken into account were recorded in the V4 variant, which was a combination of products (P500+P501). [ABSTRACT FROM AUTHOR]

Intercropping is the simultaneous cultivation of two or more crops species in the same space for a considerable proportion of the growth period. Intercropping has several advantages and is used in both traditional and sustainable agriculture. The objective of the present study was to study the interactions among different pea and wheat cultivars and the effect of water availability on wheat-pea mixtures and the competition between the two species. The experiment was conducted for two successive growing seasons using two different irrigation regimes and two cultivars from each species. The different treatments were evaluated using morphological and agronomic characteristics. Intercropping treatment, cultivars, and irrigation level affected most of the characteristics that were studied and the competition between the two species. Biomass was higher by 47% and leaf area index by 34% under irrigation compared to the rainfed conditions. The different cultivars showed different response under the two water regimes. Based on the intercropping indices, the mixture 'Yecora E' - 'Isard' is favoured under irrigation while the combination 'Elissavet' - 'Isard' under low water availability. There was interaction between cultivars and irrigation and using different cultivars in intercropping can have higher yield advantage than monocropping by exploiting the environmental resources more efficiently. Therefore, the use of appropriate cultivars in mixtures can affect the growth, biomass yield and competition between the two species leading to higher yield and greater economic return. [ABSTRACT FROM AUTHOR]

This research study evaluated the genetic variation in forage biomass yield, morphological characteristic, forage nutritional value and digestibility among five selected wheat genotypes. The five cultivars, namely, Pir Sabaq (PS)-15, Bakhtawar-92, PS-2000, National Agriculture Research Council (NARC)-11 and Zam-04 were grown in 12 replicate plots (6 m × 10 m), that were blocked in three fields according to Randomized Complete Block Design. Uniform field preparation, irrigation, weeds control and standard agronomic practices were applied to all plots. For forage yield, morphological and quality evaluation, samples were collected from randomly selected one-meter long strip of two consecutive rows of each plot at feekes stages 7 to 8, when the second last leaf was visible. The collected samples were immediately weighed, and 10 plants were subsampled from each sample for morphological evaluation. Ten plants were weighed and separated into stem and leaves portion, subsequently weighed and analysed for dry matter (DM) content. The remaining samples were air dried, ground and analysed for chemical composition and in vitro digestibility (IVDMD) and in vitro gas production (IVGP). The results revealed large variability (P < 0.001) in DM yield, ranging from 1943 to 2763 kg/ha. There was also greater variability (P = 0.001) in morphological characteristics among the wheat cultivars. The percentage of leaves varied from 0.33 to 0.45% and leaf to stem ratio varied from 0.47 to 0.84. There was also marked variation (P = 0.001) in the plant height, ranging from 68.7 to 79.3 cm. The chemical composition showed large range (P = 0.001) among the five wheat cultivars, the ash content varied from 6.01 to 7.90%, crude protein (CP) from 8.71 to 12.40% and crude fat (CFat) from 1.02 to 3.26%. The neutral detergent fibre (NDF) from 43.2 to 44.7%. The IVDMD varied from 48.4 to 58.9% and IVGP varied from 110 to 172 mL/g organic matter. Among the five wheat cultivars Bakhtawar-92 had maximum DM yield (2747 kg/ha), proportion of leaves (45%), CP (12.4%), IVDMD (58.9%) and IVGP (172 mL/g organic matter), and minimum portion of stem (55%) and NDF (43.2%), and thus supported greater yield of high quality wheat fodder. Other cultivars which combined similar desirable characteristic were ranked in order of merit as PS-15, PS-2000, NARC-11 and Zam-04. [ABSTRACT FROM AUTHOR]

Summary: Starch is the most abundant carbohydrate synthesized in plant chloroplast as the product of photosynthetic carbon assimilation, serving a crucial role in the carbon budget as storage energy. Phosphoglucose isomerase (PGI) catalyzes the interconversion between glucose 6‐phosphate (G6P) and fructose 6‐phosphate (F6P), which are important metabolic molecules in starch synthesis within chloroplasts and sucrose synthesis in cytosol.Here, we found that the specific activity of recombinantly purified PGI localized in cytosolic PGI (PGIc) was much higher than its plastidic isoenzyme counterpart (PGIp) originated from wheat, rice and Arabidopsis, with wheat PGIc having by far the highest activity. Crystal structures of wheat TaPGIc and TaPGIp proteins were solved and the functional units were homodimers.The active sites of PGIc and PGIp, constituted by the same amino acids, formed different binding pockets. Moreover, PGIc showed slightly lower affinity to the substrate F6P but with much faster turnover rates. Engineering of TaPGIc into chloroplasts of a pgip mutant of Arabidopsis thaliana (atpgip) resulted in starch overaccumulation, increased CO2 assimilation, up to 19% more plant biomass and 27% seed yield productivity.These results show that manipulating starch metabolic pathways in chloroplasts can improve plant biomass and yield productivity. [ABSTRACT FROM AUTHOR]

The circular economy is an approach that integrates the economy, the waste management system and protects the environment. The goal of the circular economy is to optimize the existing system and increase welfare. The growth trend of alternative fuels is evident in the world from year to year, thanks to the development of new technologies for processing biological waste into energy sources. Commercial production needs to be economically and environmentally friendly so that biofuels from renewable sources are an adequate substitute for fossil fuels. In this study, two winter grains, wheat and rye, were examined, during 2018/2019 and 2019/2020, in order to obtain biogas from plant biomass. The results showed that wheat had a statistically significantly higher production of biomass and biogas compared to rye. Based on the analysis of variance, it can be concluded that there are highly significant differences in biomass yield in regard to the genotype (Fexp=937.75**) and years (Fexp=28.07**) of investigation. There is a strong positive correlation between biomass and biogas yields. [ABSTRACT FROM AUTHOR]

The biomass-based soils are used in the ecological agriculture, being already proposed in sustainable organic production systems with reduced costs for assuring the good cropping productivity, and also high quality of the crops. For the elimination of the synthetic inorganic fertilizers' utilization on soil, the use of certain types of residual biomass in mixture with the reference soil was proposed as they have a positive impact on the adsorption and absorption of nutrients and water for the nutrition of plants. The aim of this paper is to present four mixtures of reference soil and residual biomass, considered as biosoil used as support for development of wheat seeds. These biosoils were characterized in terms of real density, actual and potential pH, content of total organic carbon, humus, exchangeable calcium, total and available nitrogen and phosphorus, and the trends of grain seeds germination and plants growth were registered in association with the evolution of soil pH for a period greater than a month. The results encourage the use of these biosoils (mixtures of soil with residual biomass) as support for plants cropping. [ABSTRACT FROM AUTHOR]

(Syringopais temperatella Led.) is a threat to wheat and barley. Resistant varieties are preferable due to environmental and human considerations and for their sustainability. However, no attention has been focused on resistant studies against cereal leafminer worldwide. Concomitantly, this study aimed at screening wheat and barley accessions as sources of S. temperatella resistance under semi-arid conditions of Karak-Jordan. It was also designed to evaluate the RAPD markers potential for identifying the accessions based on their resistance. The rank accessions order resulted from least to most according to infestation percentage and presence of larvae on leaves: Acsad 1245 (wheat), Acsad 1273 (wheat), 1614 (barley) and Umkais (wheat). The rank order of the same accessions from most to least according to grain yield and straw biomass: 1614, Acsad 1245, Umkais and Acsad 1273. Data on DNA (RAPD) markers revealed higher polymorphism level among accessions. Two hundred bands were noticed; and 199 were polymorphic. Total number of amplification products/primer ranged from 16 with primer (OPI-08) to 25 with primer (OPA-10), and the PCR size products ranged between 200-3500 bp. [ABSTRACT FROM AUTHOR]

With a possible reference to heat priming and to characterize the extent and variation in the heat stress responses in wheat, the effects of single vs. repeated heat stresses were examined by measuring the changes in morphological and grain yield-related traits and photosynthetic parameters. To achieve these objectives, 51 winter wheat cultivars of various geographic origins were included in two independent experiments covering different phenological stages. In Experiment I, a single heat stress event was applied at stem elongation (SE) and booting (B), and the repeated heat stress was applied at both of these stages (SE+B). In Experiment II, the single heat stress was applied at stem elongation (SE) and full heading (CH), while the repeated heat stress was applied at both stages (SE+CH). While genotype was a more important factor for determining the morphological and yield-related traits, it was the treatment effect that mostly influenced the photosynthetic parameters, with the exception of the chlorophyll content. The heading stage was more sensitive to heat stress than the booting stage, which was primarily due to the larger decrease in the average seed number. The importance of biomass in contributing to grain yield intensified with the heat stress treatments. There was a large variation between the wheat cultivars not only in yielding abilities under control conditions but also in sensitivities to the various heat stresses, based on which 7 distinct groups with specific response profiles could be identified at a highly significant level. The 7 wheat groups were also characterized by their reaction patterns of different magnitudes and directions in their responses to single vs. repeated heat stresses, which depended on the phenological phases during the second cycle of heat stress. The possible association between these findings and heat priming is discussed. [ABSTRACT FROM AUTHOR]

Wheat (Triticum aestivum L.) productivity is severely reduced by high temperatures. Breeding of heat-tolerant cultivars can be achieved by identifying genes controlling physiological and agronomical traits when high temperatures occur and using these to select superior genotypes, but no gene underlying genetic variation for heat tolerance has previously been described. We advanced the positional cloning of qYDH.3BL , a quantitative trait locus (QTL) on bread wheat chromosome 3B associated with increased yield in hot and dry climates. The delimited genomic region contained 12 putative genes and a sequence variant in the promoter region of one gene, Seven in absentia , TaSINA. This was associated with the QTL's effects on early vigour, root growth, plant biomass, and yield components in two distinct wheat populations grown under various growth conditions. Near isogenic lines carrying the positive allele at qYDH.3BL underexpressed TaSINA and had increased vigour and water use efficiency early in development, as well as increased biomass, grain number, and grain weight following heat stress. A survey of worldwide distribution indicated that the positive allele became widespread from the 1950s through the CIMMYT wheat breeding programme but, to date, has been selected only in breeding programmes in Mexico and Australia. [ABSTRACT FROM AUTHOR]

The introduction of the short arm of rye chromosome 1R (1RS) into wheat significantly increased grain yields. Studies have shown that 1RS carries a locus controlling root biomass and improves canopy water status under water-stressed conditions. The general genetic map location of the locus is known but allelic variation would facilitate precise mapping and identification of the responsible gene(s). To this end, six 1RS.1BL translocations from various sources in three wheat backgrounds were tested for root biomass and response to drought but no significant differences among different 1RS arms were observed. The behavior of the standard 1RS.1BL translocation in cv. Pavon 76 in various experiments suggested that wheat chromosome arm 1BS of Pavon 76 may carry a locus for root system plasticity. A set of single substitutions of chromosome 1B from 15 different sources, in the same genetic background of cv. Pavon 76, were tested for root biomass in various experiments. Again, no significant variation among the 1B substitution lines was observed. These results suggest that either no allelic variation at the targeted loci exists, or the sets of lines were biased. While various 1B chromosomes originated from a random sample of wheats, all 1RS arms were imported into wheat from various triticales, perhaps preselecting certain allelic combinations. [ABSTRACT FROM AUTHOR]

Antecedentes: la producción de forraje verde hidropónico (FVH) bajo invernadero es una alternativa que ha tomado importancia ante el cambio climático, porque en cortos períodos de tiempo se tiene producción sin la afectación de plagas y enfermedades que se presentan en cultivos a campo abierto. Objetivo: evaluar la dinámica de crecimiento de gramíneas como forraje verde hidropónicos bajo el sistema de bandejas para la alimentación animal en trópico alto. Métodos: se emplearon 5 gramíneas: maíz (Zea mays), raigrás (Lolium hybridum), avena (Avena sativa), trigo (Triticum sp.) y cebada (Hordeum vulgare) en hidroponía de bandejas, por un periodo de 18 días en el invernadero de la unidad experimental del semillero en el municipio de Chía, Cundinamarca. Se realizaron mediciones de altura (A) de la planta, número de hojas (NH), ancho de la hoja (AH) y biomasa (g FVH/bandeja). El diseño experimental empleado fue de bloques completos al azar distribuidos en 5 bloques, 5 tratamientos y 3 repeticiones, a los datos de las variables evaluadas se les hizo ANOVA y se empleó la prueba de Tukey para detectar diferencia significativa entre tratamientos en el paquete estadístico SAS. Se empleó el modelo de Gompertz para las curvas de crecimiento de cada una de las especies vegetales: altura al punto de inflexión (API), edad al punto de inflexión (EPI) y la tasa media de crecimiento (TMC). Resultados: se encontró diferencia significativa entre los tratamientos para todas las variables evaluadas. Las especies de mayor altura en promedio para el período evaluado fueron avena (14,66 cm), cebada (13,77 cm) y trigo (13,29 cm), el maíz tuvo mayor número y ancho de las hojas. La mayor biomasa fue para el raigrás y el trigo (7,8 vs 7,2 kg FVH/ bandeja). La mayor API fue para maíz 6,66 cm a los 20 días (EPI). La mayor TMC la tuvo la avena 2,0 cm/día. Conclusiones: el FVH raigrás y trigo ofertan la mayor biomasa, y la avena la mayor tasa de crecimiento, por lo cual estas especies se constituyen en una alternativa de alimentación como gramíneas para los animales. [ABSTRACT FROM AUTHOR]

• More accurate estimation of wheat biomass in regional to global scale. • Ability of this model to work even when the sky is overcast. • Enhancement of estimation using farmers-supplied auxiliary data. Assessment of the wheat biomass for yield prediction in regional to global scales is of particular importance, especially in food security. So far, many studies have been conducted in this subject where almost in all of them either satellite data or climatological data have been deployed. In the present study, first, some commonly used models including empirical and conventional Monteith models for wheat biomass estimate on have been evaluated where the results were found to be not quite satisfactory. Then a model named FABE, based on the farmer-provided auxiliary data along with the satellite and climatological data has been introduced. The uncertainty of the FABE model in estimating biomass was 193 (gm−2) with relative RMSE of about 0.31. This shows significant improvement compared to models such as Monteith (RMSE = 224 (gm−2) and relative RMSE = 0.36). It is shown that the biomass prediction improves if it benefits from farmer-supplied auxiliary data including wheat farms location, watering system, and digital photographs to fill up the gaps due to the satellite missing pixels/images. Accurate biomass estimation may improve the prediction of the yield. [ABSTRACT FROM AUTHOR]

The stimulated decomposition of farmyard manure (FYM) through soil amendments is considered to improve the nitrogen (N) availability and hence the crop biomass. With this view, the four soil amendments [i.e. No-amendments, Min-N (30 kg N ha-1), humic acid (2.5 kg ha-1) and effective microbes (200 L Mg-1 of FYM)] were added to five levels of FYM (i.e. 0, 5, 10, 15 and 20 Mg ha-1 ) and their impact were quantified in terms of wheat phenology, crop stand and biomass during two years studies (2016-17 and 2017-18). Min-N was provided from urea, humic acid from "humic plus" a commercial product having 40% humic acid, and effective microbes from "bioaab" a commercial product having beneficial microbes like bacteria, yeast and actinomycetes. Average over years, the maximum days to anthesis (126 days), physiological maturity (154 days) and enhanced emergence (9 days) were observed with 20 Mg FYM ha-1 . The emergence m-2 (126), leaf area tiller-1 (107 cm²), plant height (96.5 cm) and biomass (11783 kg ha-1 ) were improved with 20 Mg FYM but were non-significantly different from plots having 15 Mg FYM ha-1 over two years averaged data. Among the amendments, greater days to anthesis (126 days) and physiological maturity (154 days) was noted with effective microbes over two years. Similarly, the addition of effective microbes has increased the emergence m-2 (123), leaf area tiller-1 (105.6 cm²), plant height (96.6 cm) and biomass (11386 kg ha-1 ). The physiological maturity delayed when FYM increased from 0 to 20 Mg ha-1 and applied with effective microbes. However, using >10 Mg FYM ha-1 has no differences in emergence m-2 across the amendments. In conclusion, the addition of effective microbes can enhance crop stand and biomass when added with 15-20 Mg FYM ha-1 . [ABSTRACT FROM AUTHOR]

The development of crop varieties with higher nitrogen use efficiency is crucial for sustainable crop production. Combining high-throughput genotyping and phenotyping will expedite the discovery of novel alleles for breeding crop varieties with higher nitrogen use efficiency. Digital and hyperspectral imaging techniques can efficiently evaluate the growth, biophysical, and biochemical performance of plant populations by quantifying canopy reflectance response. Here, these techniques were used to derive automated phenotyping of indicator biomarkers, biomass and chlorophyll levels, corresponding to different nitrogen levels. A detailed description of digital and hyperspectral imaging and the associated challenges and required considerations are provided, with application to delineate the nitrogen response in wheat. Computational approaches for spectrum calibration and rectification, plant area detection, and derivation of vegetation index analysis are presented. We developed a novel vegetation index with higher precision to estimate chlorophyll levels, underpinned by an image-processing algorithm that effectively removed background spectra. Digital shoot biomass and growth parameters were derived, enabling the efficient phenotyping of wheat plants at the vegetative stage, obviating the need for phenotyping until maturity. Overall, our results suggest value in the integration of high-throughput digital and spectral phenomics for rapid screening of large wheat populations for nitrogen response. [ABSTRACT FROM AUTHOR]

This study focused on the legacy effects of 8-year application of N (in gradient of 0, 140, 280, 470, and 660 kg N ha−1 year−1) on the bacterial community diversity, interactions, and assembly processes in the wheat rhizosphere. The rhizosphere bacterial α-diversity increased with the rate of historical N input, while it did not change at N addition rates of over 280 kg N ha−1 year−1. Historical N input clearly shifted the rhizosphere bacterial community composition, and soils with more N input were more dissimilar to those without N input. The net relatedness index (NRI) and nearest taxon index (NTI) analysis revealed that the rhizosphere bacterial communities in most samples were phylogenetically clustered, and the treatments with high N (> 470 kg N ha−1 year−1) showed higher levels of clustering than those with low N (< 140 kg N ha−1 year−1), indicating more environmental selection stress in soil with higher historical N input. Increased co-occurrence network size and connectivity were accompanied by increased aboveground biomass of wheat. Overall, with the increase in historical N input, the resulting legacy effects forced the bacterial community in the rhizosphere to undergo higher environmental selection pressure, and indirectly affected the complexity of wheat rhizosphere assemblages during subsequent crop growth. [ABSTRACT FROM AUTHOR]

Strong early vigour plays a crucial role in wheat yield improvement by enhancing resource utilization efficiency. Synthetic hexaploid wheat (SHW) combines the elite genes of tetraploid wheat with Aegilops tauschii and has been widely used in wheat genetic improvement for its abundant genetic variation. The two SHWs Syn79 and Syn80 were derived from the crossing of the same tetraploid wheat DOY1 with two different Ae. tauschii accessions, AT333 and AT428, respectively. The Syn80 possessed better early vigour traits than Syn79, theretically caused by their D genome from Ae. tauschii. To dissect their genetic basis in a hexaploid background, 203 recombinant inbred lines (RILs) derived from the cross of Syn79 x Syn80 were developed to detect quantitative trait loci (QTL) for four early biomass related traits: plant height (PH), tiller number (TN), shoot fresh weight (SFW) and shoot dry weight (SDW) per plant, under five different environmental conditions. Determined from the data of SNP markers, two genome regions on 1DS and 7D were stably associated with the four early biomass related traits showing pleiotropic effects. Four stable QTLs QPh.saas-1DS, QTn.saas-1DS, QSfw.saas-1DS and QSdw.saas-1DS explaining 7.92, 15.34, 9.64 and 10.15% of the phenotypic variation, respectively, were clustered in the region of 1DS from AX-94812958 to AX-110910133. Meanwhile, QPh.saas-7D, QTn.saas-7D, QSfw.saas-7D and QSdw.saas-7D were flanked by AX-109917900 and AX-110605376 on 7D, explaining 16.12, 24.35, 15.25 and 13.37% of the phenotypic variation on average, respectively. Moreover, these genomic QTLs on 1DS and 7D enhancing biomass in the parent Syn80 were from Ae. tauschii AT428. These findings suggest that these two QTLs from Ae. tauschii can be expressed stably in a hexaploid background at the jointing stage and be used for wheat improvement. [ABSTRACT FROM AUTHOR]

The purpose of the study was to assess the relationships between physiological parameters and grain yield of different bread wheat genotypes. In the present research a total of 25 bread wheat genotypes were tested during the 2016-2017 seasons under rainfed conditions. The experiment was conducted in a randomized complete blocks design with four replications. Grain yield, days of heading, plant height, biomass (NDVI) from GS25 up to GS85 growth stage, chlorophyll content (SPAD) during the heading stage, canopy temperature (CT) at GS60 and GS75 growth stages, and glaucousness were investigated. The results of variance analyses showed that there were significant differences (p<0.01) among genotypes for yield. The mean grain yield was 7948 kg ha-1 and yield ranged from 7033 kg ha-1 to 8759 kg ha-1, the highest grain yield performed by TE6744-16 line. According to the results, significant differences among cultivars in terms of plant height, days of heading, biomass, chlorophyll content, canopy temperature, glaucousness were found. TE6627-6 line had the highest chlorophyll content and also, chlorophyll content positively affected grain yield. Canopy temperature is generally related to yield under drought stress condition in bread wheat. In the study early maturing (days of heading) genotypes had lower canopy temperature. An increase in biomass after the heading phase has positively affected grain yield. In the study, no correlation was found between grain yield and biomass at GS25 and GS45 growth phase. There was a negative correlation between glaucousness with biomass at GS60, GS75 and GS85 growth phase. These results showed that physiological parameters such as biomass (at GS75 and GS85), canopy temperature (at GS60 and GS75), and chlorophyll content (at GS60), and glaucousness could be used for selection parameters under rainfed conditions for yield in bread wheat. [ABSTRACT FROM AUTHOR]

Stem solidness in wheat is an important architectural trait to support the erect behavior of the plant. The varieties with high yield potential due to increased sink strength tend to lodge either because of poor anchorage or weak stem. The solid stem can partially counter the tradeoff between biomass driven yield gain irrespective of the plant height. Stem solidness being a complex trait with highly variable expressivity, understanding its genetic behavior in different genetic backgrounds is highly essential to integrate this trait in the breeding program. In this study, the expressivity of a solid stem in different internodes was investigated in nine F2 populations selected from 34 F1s (solid stem × hollow stem and hollow stem × hollow stem). The progeny of solid stem type F1 plants from hollow stem parents indicated the complementation of favorable alleles dispersed among the parents. Non-confirmation to digenic complementary (9:7) model of inheritance and polynomial distribution of the trait in all F2 populations indicates multiple factors complementation in the additive fashion for stem solidness. [ABSTRACT FROM AUTHOR]

Genome wide association studies (GWAS) are important in discerning the genetic architecture of complex traits such as biomass allocation for improving drought tolerance and carbon sequestration potential of wheat. The objectives of this study were to deduce the population structure and marker-trait association for biomass traits in wheat under drought-stressed and non-stressed conditions. A 100-wheat (Triticum aestivum L.) genotype panel was phenotyped for days to heading (DTH), days to maturity (DTM), shoot biomass (SB), root biomass (RB), root to shoot ratio (RS) and grain yield (GY). The panel was sequenced using 15,600 single nucleotide polymorphism (SNPs) markers and subjected to genetic analysis using the compressed mixed linear model (CMLM) at false discovery rate (FDR < 0.05). Population structure analysis revealed six sub-clusters with high membership ancestry coefficient of ≤0.65 to their assigned sub-clusters. A total of 75 significant marker-trait associations (MTAs) were identified with a linkage disequilibrium threshold of 0.38 at 5cM. Thirty-seven of the MTAs were detected under drought-stressed condition and 48% were on the B genome, where most quantitative trait loci (QTLs) for RB, SB and GY were previously identified. There were seven pleiotropic markers for RB and SB that may facilitate simultaneous selection. Thirty-seven putative candidate genes were mined by gene annotation on the IWGSC RefSeq 1.1. The significant MTAs observed in this study will be useful in devising strategies for marker-assisted breeding for simultaneous improvement of drought tolerance and to enhance C sequestration capacity of wheat. [ABSTRACT FROM AUTHOR]

The effect of increasing rates of potassium (K) fertiliser was studied on a soil with base exchangeable K values ≤ 0.1 cmol(+)/ kg by assessing biomass, feed quality, mineral concentration and grain yield for wheat, triticale and canola. The crops showed variable biomass response to K rates at early plant growth stages, however at anthesis there were significant positive biomass responses to increasing rates of K. A positive K rate effect was detected on feed quality with significant increases in metabolisable energy. Irrespective of sampling time, increasing K rate resulted in significant increases in crop K concentration and mineral ratios, such as the Tetany index, but significant decreases in Ca and Mg concentrations. Final grain yield was significantly increased by K rate and there were beneficial effects on grain quality (thousand grain weight). Overall, this study highlights the importance of K to production responses and implications for the health and productivity of grazing livestock. [ABSTRACT FROM AUTHOR]

A field experiment on wheat varieties was carried out at Agroforestry Research Centre, G.B. Pant University of Agriculture and Technology, Pantnagar. The experimental plots were laid out in randomized block design with two associate farming systems, open farming and poplar-based agroforestry system, and four varieties of wheat, viz. PBW-373, PBW-343, UP-262 and VL-907, with three replications. The average tree growth parameters, viz. plant height, diameter and crown width of poplar showed an increase at the rate of 8.43%, 12.36% and 17.91% respectively. Growth and yield attributes of wheat like germination count, leaf area index, plant height, dry matter accumulation, as well as yield of wheat were found higher in open farming compared to poplar-based agroforestry system. The yield characters of wheat, such as biological yield (112.01 q ha-1), grain yield (42.19 q ha-1), straw yield (69.93 q ha-1) and harvest index (39.82) were recorded maximum in VL-907 followed by PBW-343, except for straw yield. Among soil chemical properties, electrical conductivity, organic carbon, and available NPK were higher, whereas pH was lower under poplar-based agroforestry system compared to open farming system. Above-ground, below-ground and total biomass, carbon stock and carbon sequestration were significantly higher in agroforestry system (130.42, 17.75, 148.17, 65.20 and 239.27 q ha-1 respectively) compared to open farming. [ABSTRACT FROM AUTHOR]

Traditionally, the growth and physiological status of winter wheat (Triticum aestivum L.) is monitored in the fi eld by measuring different biophysical and biochemical variables such as Above Ground Biomass (AGB), Nitrogen content (N), N uptake, Leaf Area Index (LAI), Fraction of vegetation Cover (fCover), Canopy Chlorophyll Content (CCC), and fraction of Absorbed Photosynthetically Active Radiation (fAPAR). The objective of this study was to investigate the possibility of estimating these crop variables through statistical regression modelling and spectral vegetation indices derived by the Sentinel-2 satellites. Field data were collected over two growing seasons, 2016/2017 and 2017/2018, in test fi elds around Knezha, northern Bulgaria. A combination of spectral data from Sentinel-2 images and fi eld spectroscopy obtained through the fi rst growing season was used for model calibration and cross-validation. The models were further validated with Sentinel-2 image data from the second growing season. The accuracy of the models varied widely across crop variables. According to the cross-validation, the relative RMSE was below 25% for fAPAR, fCover, and fresh AGB, with particularly good result for fAPAR (13%). For N content and dry AGB the error was between 25% and 30%. The accuracy was low for CCC, LAI, and N uptake (error between 30% and 43%). The models' performance was worse when they were applied to the data from the second growing season, resulting in relative RMSE which were 3-8% higher in the general case. The cross-validation results suggested that the variety-specific models are more accurate than the generally calibrated models for most crop variables. The accuracy obtained in this study for the prediction of fAPAR, fCover and AGBf through VIs is promising. Future studies and incorporation of new fi eld data will be needed to better account for variety, season, and site variations in the modelled relationships and to improve their generalisation potential. [ABSTRACT FROM AUTHOR]

Organic and inorganic soil amendments are used to increase crop yields and fertilizer efficiency, as well as to improve the physical and biological properties of soil, increase carbon sequestration, and restore contaminated and saline soils. The present study aimed to evaluate the effect of various zeolite composites mixed with either lignite or leonardite on the biomass production of spring wheat and rapeseed and their root morphology. A pot experiment involved the application of the following treatments: zeolite-carbon, zeolite-vermiculite composites, both mixed with lignite or leonardite, and a control treatment with no amendments. Inorganic composites were applied in a dose of 3% and 6%. The study also included an analysis of the root morphometric parameters and aboveground biomass of spring wheat and rapeseed. The lowest productivity was observed when both crops were not enriched with fertilizers or other amendments, 24.92 g per pot and 29.83 g per pot for spring wheat and rapeseed, respectively. The application of mineral fertilizers in combination with zeolite-carbon composite gave the highest aboveground biomass of spring wheat, 110.11 g per pot. Both zeolite-carbon and zeolite-vermiculite composites modified the morphological parameters of roots, with the control treatment showing the lowest root length and dry matter. Although mineral fertilization was found to have a positive impact root development in relation to untreated control, the treatment amended with zeolite-carbon composite and leonardite exhibited the highest root length and biomass of spring wheat. No other soil amendments improved the properties of rapeseed roots. [Display omitted] • Organic/inorganic composites were applied in spring wheat and rapeseed. • The lowest yield were obtained for Control. • Highest productivity was for mineral fertilization with zeolite-carbon composite. • Zeolite-carbon and zeolite-vermiculite increased root length and biomass. • The highest root length was for zeolite-carbon with leonardite. [ABSTRACT FROM AUTHOR]

Summary: One of the major challenges for plant scientists is increasing wheat (Triticum aestivum) yield potential (YP). A significant bottleneck for increasing YP is achieving increased biomass through optimization of radiation use efficiency (RUE) along the crop cycle. Exotic material such as landraces and synthetic wheat has been incorporated into breeding programmes in an attempt to alleviate this; however, their contribution to YP is still unclear. To understand the genetic basis of biomass accumulation and RUE, we applied genome‐wide association study (GWAS) to a panel of 150 elite spring wheat genotypes including many landrace and synthetically derived lines. The panel was evaluated for 31 traits over 2 years under optimal growing conditions and genotyped using the 35K wheat breeders array. Marker‐trait association identified 94 SNPs significantly associated with yield, agronomic and phenology‐related traits along with RUE and final biomass (BM_PM) at various growth stages that explained 7%–17% of phenotypic variation. Common SNP markers were identified for grain yield, BM_PM and RUE on chromosomes 5A and 7A. Additionally, landrace and synthetic derivative lines showed higher thousand grain weight (TGW), BM_PM and RUE but lower grain number (GM2) and harvest index (HI). Our work demonstrates the use of exotic material as a valuable resource to increase YP. It also provides markers for use in marker‐assisted breeding to systematically increase BM_PM, RUE and TGW and avoid the TGW/GM2 and BM_PM/HI trade‐off. Thus, achieving greater genetic gains in elite germplasm while also highlighting genomic regions and candidate genes for further study. [ABSTRACT FROM AUTHOR]