Search Results (367)

As one of the world’s leading grain producers, Brazil stands out in soybean and corn production. Accurate estimation of key crop phenological stages is essential for agricultural decision-making, especially considering Brazil’s vast territory, climatic diversity, and increasing frequency of extreme weather events. This study investigated the applicability of the NDVI, EVI, WDRVI, and NDWI, derived from Harmonized Landsat Sentinel-2, to identify crop sowing and harvest dates at the field scale. We extracted the vegetative peak from each vegetation index time series and identified the left and right inflection points around the peak to delineate the crop season. A double-logistic function and a derivative approach were applied to identify the Start of Season, Peak of Season, and End of Season. For both soybeans and corn, the RMSE ranged from 5 to 8 days for sowing dates, while for harvest dates it ranged from 6 to 15 days for corn. Despite these differences, all vegetation indices exhibited robust performance, with Spearman correlation values between 0.56 and 0.84. Our findings indicate that the use of different indices does not have a significant impact on the results, as long as the adjustment of temporal parameters for the phenological metrics is appropriate for each index. Full article

Porcine reproductive failure (PRF) is a complex that affects reproductive parameters, leading to significant economic losses for intensive swine farms worldwide. The causes of PRF involve multiple infectious agents, classified into two main groups: primary or putative viruses, which include PCV2, PPV1, and PRRSV, and secondary or occasional viruses, such as PCV3, PCV4, and the new parvoviruses (nPPVs, PPV2 through PPV8). This review provides an updated overview of both viral groups, detailing their unique characteristics and the most commonly reported clinical signs and lesions linked to the putative viruses. While the impact of primary viruses on PRF is well established, the role of secondary viruses in PRF is still under investigation. PCV3 has been directly associated with PRF, characterized by proposed histopathological lesions. Although PCV4 has been identified in reproductive samples, its role in PRF remains unclear. Additionally, nPPVs have been found in reproductive tissues; however, a clear causal relationship with PRF has not been established. The sporadic presence of nPPVs raises questions about their direct impact on PRF and whether they may have synergistic effects when combined with other viruses. This review highlights the growing importance of viral coinfections in the context of PRF. To date, the most frequently reported coinfections are PCV2/PRRSV and PCV2/PPV1, along with emerging pairings such as PCV2/PCV3 and combinations of these two PCVs with nPPVs. Based on the existing literature and our recent findings, we propose a subclinical presentation of PRF, characterized by the presence of both primary and secondary viruses in asymptomatic sows with low viral loads. Furthermore, the synergistic effects of these viruses could contribute to a clinical form of the disease. Full article

Hemp (Cannabis sativa L.), as a valuable source of biomass, has been utilized for textile purposes, the production of environmentally friendly polymeric materials, modern composites, and paper. Moreover, hemp can be used for biofuel production. Therefore, optimal conditions for the cultivation of hemp varieties are essential. The aim of this study was to optimize agronomic practices—sowing date, row spacing, and mineral fertilization —to maximize straw and seed yield of the monoecious hemp cultivar ‘Henola’ under temperate climate conditions. Field experiments were conducted over three growing seasons using a randomized block design, testing five fertilization treatments, three sowing dates, and three row spacings. Statistical analysis revealed that high nitrogen doses (PK + 120 N) significantly increased both straw and seed yields. The optimal sowing period was from late April to early May. Narrower row spacings (0.2 m and 0.35 m) favored higher seed yields, while row spacing had no significant effect on straw biomass. These findings support the development of evidence-based recommendations for maximizing hemp yield depending on end-use objectives. Full article

High nighttime temperature (HNT) due to asymmetric diurnal warming threatens wheat productivity. This study evaluated the effect of HNT on wheat phenology, physiology, and yield through field and controlled environment experiments in Central Queensland, Australia. Two wheat genotypes, Faraday and AVT#6, were assessed under three sowing dates—1 May (Early), 15 June (Mid), and 1 August (Late)—within the recommended sowing window for the region. In a parallel growth chamber study, the plants were exposed to two nighttime temperature regimes, of 15 °C (normal) and 20 °C (high), with consistent daytime conditions from booting to maturity. Late sowing resulted in shortened vegetative growth and grain filling periods and increased exposure to HNT during the reproductive phase. This resulted in elevated floret sterility, lower grain weight, and up to 40% yield loss. AVT#6 exhibited greater sensitivity to HNT despite maturing earlier. Leaf gas exchange analysis revealed increased nighttime respiration (Rn) and reduced assimilation (A), resulting in higher Rn/A ratio for late-sown crops. The results from controlled environment chambers resembled trends of the field experiment, producing lower grain yield and biomass under HNT. Cumulative nighttime hours above 20 °C correlated more strongly with yield losses than daytime heat. These findings highlight the need for HNT-tolerant genotypes and optimized sowing schedules under future climate scenarios. Full article

Achieving food security for a growing population under a changing climate is a key concern in Senegal, where agriculture employs 77% of the workforce with a majority of small farmers who rely on the production of crops for their subsistence and for income generation. Moreover, due to the underproductive soils and variable rainfall, Senegal depends on imports to fulfil 70% of its food requirements. In this research, we considered four crops that are crucial for Senegalese agriculture: millet, sorghum, peanuts and rice. We used crop simulation models to explore existing yield gaps and optimal agronomic practices. Improving the N fertilizer management in sorghum and millet resulted in 40–100% increases in grain yields. Improved N symbiotic fixation in peanuts resulted in yield increases of 20–100% with highest impact in wetter locations. Optimizing irrigation management and N fertilizer use resulted in 20–40% gains. The best N fertilizer strategy for sorghum and millet included applying low rates at sowing and in early development stages and adjusting a third application, considering the expected rainfall. Peanut yields of the variety 73-33 were higher than Fleur-11 in all locations, and irrigation showed no clear economic advantage. The best N fertilizer management for rainfed rice included applying 30 kg N/ha at sowing, 25 days after sowing (DAS) and 45 DAS. The best combination of sowing dates for a possible double rice crop depended on irrigation costs, with a first crop planted in January or March and a second crop planted in July. Our work confirmed results obtained in field research experiments and identified management practices for increasing productivity and reducing yield variability. Those crop management practices can be implemented in pilot experiments to further validate the results and to disseminate best management practices for farmers in Senegal. Full article

Phacelia tanacetifolia Benth. is a species of annual plant that has been gaining importance in recent years. Initially, it was treated as an ornamental plant and valuable only to bees. Over the years, this species has become more widely known, and many more of its advantages have been discovered. The aim of this study was to learn about the contemporary economic importance of Phacelia tanacetifolia Benth. The extraordinary, rapid increase in the plant’s biomass means that it is valued as a fodder plant and at the same time is included in the group of leaders among catch crops. It is characterized by low requirements for soil quality. The main advantage of this plant is its high resistance to drought and frost. A great advantage of this plant is its high drought resistance. It is recommended for sowing both in monoculture and in mixtures with other species. In the light of current standards and assumptions, it fits perfectly into the framework of sustainable development. It is a valuable link in the biodiversity chain, as well as support for a number of ecosystem services such as CO₂ sequestration, retention of nutrients in the soil or protection of its structure. Phacelia is seen as having great potential as a plant that provides food for a number of pollinators. The latest research also focuses on assessing the possibility of using it for energy purposes (biogas). Efforts are being made to introduce phacelia on a wider scale to eliminate crop monocultures and significantly strengthen biodiversity in a given area. Phacelia plays an important role in various agronomic systems and effectively supports the protection of the natural environment. The contribution of this species to the development of ecosystem services to date is undeniable. It should be assumed that this plant will continue to significantly support a number of activities for sustainable development. Full article

Accurately estimating leaves’ relative chlorophyll contents (widely represented by Soil and Plant Analysis Development (SPAD) values) across growth stages is crucial for assessing crop health, particularly in regions characterized by varying sowing dates. Unlike previous studies focusing on high-resolution UAV imagery or specific growth stages, this research incorporates satellite-derived texture indices (TIs) into a SPAD value estimation model applicable across multiple growth stages (from tillering to grain-filling). Field experiments were conducted in Jiangsu Province, China, where winter wheat sowing dates varied significantly from field to field. Sentinel-2 imagery was employed to extract vegetation indices (VIs) and TIs. Following a two-step variable selection method, Random Forest (RF)-LassoCV, five machine learning algorithms were applied to develop estimation models. The newly developed model (SVR-RBF_VIs+TIs) exhibited robust estimation performance (R² = 0.8131, RMSE = 3.2333, RRMSE = 0.0710, and RPD = 2.3424) when validated against independent SPAD value datasets collected from fields with varying sowing dates. Moreover, this optimal model also exhibited a notable level of transferability at another location with different sowing times, wheat varieties, and soil types from the modeling area. In addition, this research revealed that despite the lower resolution of satellite imagery compared to UAV imagery, the incorporation of TIs significantly improved estimation accuracies compared to the sole use of VIs typical in previous studies. Full article

False cleavers (Galium spurium L.) is a broadleaf weed species that affects wheat productivity because of its strong competition for resources. It has developed resistance to acetolactate synthase (ALS) inhibitors, such as sulfonylureas and triazolopyrimidines, which are herbicides widely used in durum wheat. Integrated weed management programs can contribute to the control of this species and delay the evolution of herbicide resistance. Thus, a two-year field experiment was conducted to evaluate the effects of sowing time, variety, and herbicides on crop yield, density, and dry weight of a false cleavers population with resistance to ALS inhibitors. In both growing seasons, a split-split-plot design was used with three replicates. The sowing date was chosen as the main plot factor, durum wheat varieties as the subplot factor, and herbicides as the sub-subplot factor. The herbicide treatments were: (1) metsulfuron-methyl/bensulfuron-methyl (4/50 g a.i. ha⁻¹), (2) aminopyralid/florasulam (9.9/4.95 g a.i. ha⁻¹), (3) pyroxsulam and florasulam/2,4-D (18.75 + 4.725/225 g a.i. ha⁻¹), (4) 2,4-D/bromoxynil (633.15/601.2 g a.i. ha⁻¹), non-treated control, and hand-weeded control for the first season, while in the second season one more herbicide treatment (halauxifen-methyl/florasulam, 5.6/5.15 g a.i. ha⁻¹) was added. Herbicide application was performed on 10 March 2021 and 28 March 2022, when the crop was at the end of tillering and the beginning of stem elongation. The results showed that the density of false cleavers was not affected by the variety or sowing time. However, its dry weight was 17.3–23.4% higher in early sowing (16 November in 2020 and 8 November 2021) than in late sowing (24 December 2020 and 2 December 2021). Among the herbicides tested, 2,4-D/bromoxynil and halauxifen-methyl/florasulam effectively controlled false cleavers, showing greater efficacy in late sowing (>88%), which ultimately led to a higher yield. In conclusion, our two-year findings demonstrate that delayed sowing as part of an integrated weed management strategy can contribute to controlling resistant populations of false cleavers to ALS-inhibiting herbicides without affecting the quantity and quality of durum wheat yield in areas with a Mediterranean climate. Full article

Late sowing and spring low temperatures have a great impact on the growth and maturation of wheat in the rice–wheat rotation region. In order to analyze the impacts of cold stress in February in early spring on yield formation and agronomic traits of wheat on different sowing dates, a controlled pot experiment was performed using the widely promoted and applied spring-type wheat variety Yangmai23 (YM23). The yield of wheat treated with late sowing date II (SDII, 21 November) and overly late sowing date III (SDIII, 9 December) were both lower than that of wheat sown on the suitable date I (SDI, 1 November). The yield of late-sown wheat decreased by 40.82% for SDII and by 66.77% for SDIII, compared with SDI, and these three treatments of wheat all grew under the natural conditions as the control treatments. The plant height, stem diameter of the internode below the ear, flag leaf length and area, and total awn length of the spike, as well as the spike length of late-sown wheat, were all significantly lower than those of wheat in SDI treatment. Early spring low temperatures exacerbated the decline in yield of wheat sown on different dates, to some extent. Despite showing higher net photosynthetic rate, stomatal conductance, and transpiration rate in flag leaves of the SDIII treatment under low-temperature stress than those of the other treatments at anthesis, overly late sowing led to minimal leaf area, shorter plant height, fewer tillers, and smaller ears, ultimately resulting in the lowest yield. Our study suggested that additional focus and some regulation techniques are needed to be studied further to mitigate the combined negative impacts of late sowing and low-temperature stress in early spring on wheat production. Full article

The current study aimed to determine the optimum agronomic conditions—specifically sowing date and seeding density—for soybean cultivation in a temperate climate. A field experiment was conducted to evaluate three sowing dates based on soil temperature (S1—9 °C, S2—12 °C, S3—15 °C) and three seeding densities (D1—50, D2—70, D3—90 seeds·m⁻²). A field experiment was conducted in the years 2017–2019 in eastern Poland (Central Europe). Yields were strongly influenced by weather conditions. In 2019, the average yield was 2.61 Mg·ha⁻¹, making it the most favorable year, whereas 2018 was the least favorable, with an average yield of 1.41 Mg·ha⁻¹. Seeding density also affected soybean yields—the highest yield was obtained at the medium density (D2—2.36 Mg∙ha⁻¹). On the other hand, the highest thousand seed weight (159.30 g·m⁻²) was achieved at the lowest density (D1). Plant height and pod length depended on the sowing date. The tallest plants (69.96 cm) and the longest pods (4.55 cm) were obtained with early sowing (S1). The number of seeds per pod ranged from 1.8 to 2.7, with the highest values recorded in 2017, mainly with early sowing (S1) and low density (D1). It is recommended that sowing strategies be flexibly adjusted to the meteorological conditions of a given season. The findings indicate that appropriate selection of sowing parameters can significantly enhance the efficiency and stability of soybean yields under the variable climatic conditions of Poland. Full article

This work proposes an insight into the mycotoxins detected in wheat from the 2023 and 2024 harvests in Belgium and highlights the link between agronomic conditions and mycotoxin contamination. The study utilized samples from a Belgian trial network, covering nine locations in 2023 and eight in 2024, ensuring diverse pedoclimatic contexts and including 11 different varieties. Sowing and harvest dates, previous crops and meteorological data were collected for these locations. A validated UPLC-MS/MS multi-mycotoxin method able to detect 20 mycotoxins, regulated or not, was used. Deoxynivalenol, zearalenone, and enniatins B and B1 were detected in the 2023 and 2024 samples. Enniatin A1 was only detected in the 2024 samples. Mycotoxin contamination was higher in 2024 compared to 2023, in terms of both the number of contaminated samples and the contamination levels. Enniatins B and B1, non-regulated mycotoxins, were widely detected in the 2024 wheat samples, with enniatin B detected in 68 out 88 samples ranging from 12 to 488 µg/kg. Differences between the wheat varieties were observed, with some varieties showing significantly higher contamination. Additionally, geographic location appeared to influence contamination levels, which could be related to previous crops or meteorological events. In conclusion, this research provides a comprehensive analysis of mycotoxin co-contamination in wheat samples from diverse pedoclimatic contexts in Belgium based over 2 years. It shows the importance of weather conditions on mycotoxin contamination. It also emphasizes the importance of variety selection to manage mycotoxin contamination. Full article

Melon is a valuable crop that generates significant by-products during consumption and processing. Among these, seeds are rich in phenolic compounds and might be used to produce sprouts with increased content of these bioactive substances. This study evaluated phenolic compounds (PhCs) in sprouts of two melon cultivars, Thales and SV9424ML, obtained from seeds having different germination speeds, thus harvested at 6 and 14 days after sowing (DAS). A factorial combination of cultivar and harvest time was tested in a completely randomized design with four replicates. Thales produced more ready-to-eat sprouts at 6 DAS than SV9424ML (64.0% vs. 46.7%). Sprouting significantly increased total PhCs content, particularly flavonoids, with Thales showing higher values than SV9424ML (50.2 vs. 32.6 mg kg⁻¹ DW). Phenolic profiles significantly varied among cultivars and harvests. Sprouts at 6 DAS had more total hydroxybenzoic acids and flavonoids, while 14 DAS sprouts were richer in hydroxycinnamic acids. Significant differences between harvest dates were observed in the concentrations of protocatechuic, vanillic (VanA), p-coumaric (p-CouA), ferulic (FerA) acids, and orientin (Ori) for Thales, and of VanA, p-CouA, FerA, and Ori for SV9424ML. Results are encouraging, but future investigations are essential to understand whether these sprouts can be suitable for fresh consumption, food supplements, or phytochemical extraction. Full article

Sowing date significantly affects plant growth, development, and yield, holding a crucial role in soybean cultivation. This study was conducted in the southern coastal region of Korea under recent climate change conditions to investigate the effects of five different sowing dates on climatic characteristics, growth, and yield. Compared to historical data, the southern coastal region has experienced a consistent increase in average temperature during the soybean cultivation period, along with frequent abnormal summer climate events such as concentrated heavy rainfall and monsoons. These climate changes prolonged the vegetative growth period in earlier sowings, leading to an increased risk of lodging at maturity due to vigorous vegetative growth. Furthermore, earlier sowing delayed flowering and exposed plants to longer post-flowering photoperiods, consequently reducing the number of pods. Therefore, in the southern coastal region of Korea, it is crucial to re-evaluate conventional sowing practices and establish region-specific optimal dates, with careful consideration given to postponing the soybean sowing date to late June in order to enhance yield stability and improve the feasibility of double-cropping systems by shortening the growing period. Full article

The delayed sowing date and basal internode lodging caused by climate change are major constraints on wheat productivity. To investigate the effects of varying sowing dates and fertilization application regimes on wheat yield and lodging resistance, a two-year field experiment was conducted with two sowing dates and five fertilization application regimes. Results revealed that the T2 sowing period caused grain yield reductions of 43.82% and 29.82% over two consecutive years, accompanied by shortened second basal internode length and decreased plant height, although lignin content increased significantly. Among fertilization treatments, S4 effectively enhanced the mechanical strength of the second basal internode, achieving both higher yield and superior lodging resistance. We propose combining controlled-release nitrogen fertilizer (CRNF) with urea across different sowing dates to optimize productivity and stem stability. These strategies tackle climate-driven sowing delays and lodging while maximizing yield potential. Full article

Tartary buckwheat is an important characteristic multigrain crop, mainly planted in Sichuan, Guizhou, Yunnan and Tibet, and other alpine and remote ethnic mountainous areas. In order to clarify the effect of sowing date on the yield and quality of Tartary buckwheat and its relationship with meteorological factors The variety Jinqiao No. 2 was used for a two-year trial at Dingxiang Test Base in Shanxi Province on four sowing dates (15 June, 26 June, 6 July and 17 July 2022 and 19 June, 30 June, 10 July and 21 July 2023) starting from the bud stage. Responses to sowing date were investigated by examining the growth period structure, yield, yield component, quality, and their relationship to climatic factors. The results showed that meteorological factors during the grain grain-filling stage were different when the sowing date was different. Compared with other sowing times, the treatment with the sowing of early and mid-July had less than 13.5~27.9 h of sunshine, less than 28.8~48.5 mm of rainfall, more than 10.5~19 days of ≤15 °C days, but the most serious low-temperature stress (≤15 °C days up to 27 days). The yield of sowing in July was 69.8~77.0% and 69.9~79.1% lower than that of sowing in June in 2022 and 2023 respectively, and the later sowing had a lower yield. Delayed sowing is beneficial to the accumulation of flavonoids and protein in Tartary buckwheat grains, and the average value in 2022 and 2023 is 11.55% and 14.64% higher than that in the first sowing, but the content of fat and starch is significantly reduced. The result of path analysis showed that the low temperature (≤15 °C days up to 27 days) and less solar radiation duration were the key points for attaining high yield and quality, due to the mean daily temperature and ≤15 °C days from flowering to maturity had negative effect on 1000-seed weight, seed setting rate, starch and crude lipid content of Tartary buckwheat, and the direct effect of sunshine duration on the content of protein and flavonoid in Tartary buckwheat was the greatest. The yield of Tartary buckwheat sown in June was higher than that of other treatments, because of avoiding low-temperature stress and long rainy and sunless weather during the grain filling stage, which enabled the blossoming and grain filling normally and finally attained higher yield. Full article