Journal of Agronomy and Crop Science最新文献

Waterlogging affects a high proportion of cultivated land worldwide. Sunflower, soybean and sorghum growth and yield can be affected differently depending on the moment and duration of waterlogging stress. If stress conditions occur during the critical period for yield potential definition (flowering in, sunflower and sorghum and end of pod formation in soybean) they directly reduce grain number, but if the stress occurs during the grain-filling period, grain weight would be affected. The aim of this study focuses on determining the effects of the moment and duration of waterlogging stress on the yield and its components in sunflower, soybean and sorghum. This information will be useful to understand the effects of waterlogging on yield and to choose a suitable crop or sowing date based on predicted weather conditions for a certain place. To achieve this objective, four experiments were conducted at the Experimental Station of INTA (Reconquista, Santa Fe, Argentina). The effect of the waterlogging in terms of moment (vegetative, critical and grain-filling periods) and duration (3, 7 and 10 days) on the three crops was evaluated. Sunflower expressed the most negative impact of waterlogging during the vegetative stages (26, 78 and 98% of yield losses with 3, 7 and 10 days, respectively) while soybean suffered major reductions when the stress occurred during the critical period (5%–17% of yield loses). Sorghum did not express any negative responses for the moments and durations tested. This study suggests that the critical period for a waterlogging event differs, according to crops, from the critical period cited for other stresses. Moreover, the magnitude of the damage will mainly depend on the duration of the event. Further studies are needed to elucidate different physiological responses of the species during waterlogging stress.

Heat and drought are two important constraints to global wheat productivity; understanding the genotypic responses for quality parameters under harsh production conditions (drought and heat) is very important for developing nutrient-dense wheat varieties. A set of 15 modern bread wheat (Triticum aestivum L. subsp. aestivum) and durum wheat (Triticum turgidum subsp. durum) cultivars were tested in nine environments, including three different production conditions (normal, heat and drought) during 2020–21. Genotype stability performance for yield, nutrition and quality parameters is assessed using multienvironment trials through AMMI and GGE Biplot analysis. We discovered intriguing stress dynamics in grain zinc content (Zn) and grain iron content (Fe). Under heat stress, zinc concentration increases but decreases under drought stress, while iron does the opposite. Selecting zinc, starch and kernel weight under terminal heat stress can boost yield. Protein content and yield are inversely related, making it difficult for breeders to optimise both traits. G × E interactions and stability indices across all environments have found genotypes with high-yielding stable genotypes, G12 (MP1358) (42.09 ppm) and G5 (HI1544) (42.41 ppm) have high Fe content. G12 (MP1358) (14.98%) ranked highest in protein concentration. Meanwhile, for Zn content, G11 (MACS 4058) (45.23 ppm) and G15 (WH730) (42.44 ppm) were top performers across environments. G7 (HI 1636) and G12 (MP1358) stand out as a win-win genotype for their high potential and stability in yield, protein, Zn and Fe content. Our study shows the complex relationships and possible suggestions for targeted breeding programmes under heat and drought stress conditions to improve wheat grain quality and micronutrient profiles without yield loss.

A significant basis for winter wheat production in China is the North China Plain (NCP). However, winter wheat production is severely hampered by water shortages in this area. Transpiration co-occurs with photosynthesis, affecting crop water productivity (CWP). The purpose of this experiment is to use Root Zone Water Quality Model (RZWQM2) to study actual transpiration (AT) and evaporation (AE) under different irrigation schedules and then determine its impact on grain yield and CWP. In the 2019–2022 winter wheat growing seasons, four experimental treatments were set up: no irrigation during growth period (I0), irrigation at jointing stage (I1), irrigation at jointing and anthesis stage (I2) and irrigation at jointing, anthesis and filling stage (I3), and the RZWQM2 model was calibrated and verified in this experiment. A higher yield (7840.90 kg/ha for an average of 3 years) and the highest CWP can be obtained in I2 treatment (increased by 12.72%, 5.98% and 4.28% for an average of 3 years, respectively, compared to the other three treatments). The model has a good simulation effect on soil water dynamic change and plant physiological performance of the four treatments; the model showed that irrigation increased the simulated AE and AT; however, reduced AE/actual evapotranspiration. For the whole growth period, AT in I3, I2, I1 and I0 was 351.70, 317.30, 271.50 and 223.70 mm, respectively. Especially in the late growth stage of winter wheat, the AT in I3 was 65.20 mm for an average of 3 years, which was significantly higher than I2, I1 and I0 by 31.60, 13.50 and 10.00 mm, respectively. Thus, I3 increased AT at the late growth stage of winter wheat and resulted in an increase in grain yield; however, it did not significantly increase CWP. This study demonstrated that irrigation at winter wheat jointing and anthesis stages can improve the CWP to achieve the goal of stable grain yield and water saving.

The reduction of photosynthetically active radiation impacts the growth and productivity of soybean in agroforestry and intercropping systems. Thus, this report explored the responses of 16 soybean cultivars submitted to shade levels in field conditions. Multi-faceted and relative importance analyses revealed that the steam diameter and plant height are fundamental morphological markers for selecting shade-resilient cultivars, both were high and positively correlated to yield components. Moreover, the responses to shade varied among soybean cultivars, with certain genotypes demonstrating distinct tolerance levels, which allowed also the estimative of genetic variance that revealed strong participation of genetic components in responses to shade. Multivariate and clustering analysis using steam diameter and plant height in combination with two yield components resulted in the identification of four soybean cultivars more tolerant to shade environments and two sensible. Therefore, this report provides insights into soybean cultivation under varying light conditions, provides a robust foundation for the integration of morphological and yield markers in breeding programmes focused on shade tolerance and guides future endeavours in crop improvement for optimal and sustainable yield and resilience in the climate change context.

Agriculture plays an important part in the overall growth and development of a nation. Concerns about agriculture continue to be a recalcitrant obstacle in the path of upward movement. Although agricultural yields are increased, however, low- and middle-income countries still have difficulty in producing all of the required foods with the current state of agricultural technology. Smart agriculture is becoming increasingly important to the farmers as a means of ensuring optimal field growth and higher crop yield. This systematic study analysed and briefly explained the effects of using smart agriculture techniques (SATs) from a variety of countries, including China, the United States of America, Australia, India, the Philippine Islands, South Africa, Pakistan and Iran, among others. Increased climatic change resulting in abiotic stress and other harmful effects on plants have resulted in decreased productivity under traditional agricultural practices. Stats from the literature have shown that the launching of SATs has resulted in a significant increase in cotton–wheat and rice–wheat crop yields, resultantly increased incomes of the farmers. Application of SATs, including satellite remote sensing, drones, machine learning and image processing, monitoring, wireless sensor networks, IoT–based robotics, precision agriculture and agroforestry could be extremely useful in developing intelligent agricultural systems in underdeveloped and developing countries, with improved plant growth, high crop yield and ensuring food security. These technologies could help farmers by storing additional water, spraying pesticides with drones, practicing precision agriculture and employing sensors for assessing different environmental parameters. By making efficient use of these technologies, countries could be able to increase the yield of their crops, which, in turn, will contribute to the reduction of poverty and the elimination of food insecurity.

The lack of suitable genetic resources for saline regions and the complexity of the traits involved impede the progress in crop breeding for salt tolerance. The present investigation was carried out using 27 diverse barley genotypes chosen based on the assessment of salt tolerance potential within the barley mini-core collection at the National Genebank of India. The genotypes were exposed to salinity stress (200 mM NaCl) and were examined for morpho-agronomic, physiological traits and salt uptake parameters. Exposure to salt stress resulted in a significant decline in all parameters ranging from 5.94% in relative water content to 80.04% in shoot K⁺/Na⁺ ratio compared to the control in the evaluated accessions. Moreover, the grain yield and its key attribute hundred-grain weight decreased substantially by 65.35% and 48.62%, respectively, under saline treatment. The majority of the resilient accessions managed to uphold a higher K⁺/Na⁺ ratio ranging from 0.51 in EC0578359 to 1.19 EC0578251 in contrast to vulnerable germplasm (<0.56) under saline circumstances. The analysis of haplotype variants disclosed allelic diversity linked with two promising candidate genes, HVA1 and HvHKT2, recognised for conferring salt tolerance. Examination of nucleotide sequences revealed that the HVA1 remained considerably conserved among the evaluated genotypes as the majority of the SNPs (single-nucleotide polymorphisms) were synonymous. Conversely, for HvHKT2, a significant level of genetic variation led to the identification of two primary haplotypic clusters—Hap1 associated with sensitivity to salinity and Hap2 linked with tolerant traits. Hap2 predominantly consisted of In/Dels which caused a modification in the overall protein length alongside the phospho-variant allelic form of the HKT2 gene, further enhancing the biological specificity and functional stress response in a spatiotemporal fashion. These haplotype clusters correlated with favourable traits could be utilised for trait integration into breeding populations, thereby expediting the enhancement of superior salt-tolerant barley cultivars.

Biological nitrogen fixation (BNF) in legume crops is a crucial ecosystem service that enhances soil nitrogen and reduces the need for chemical fertilisers. This study evaluates the factors influencing the proportion of plant nitrogen derived from atmospheric fixation (Ndfa) in legume crops. We compiled a global dataset spanning from 1980 to 2018 and used the ¹⁵N method to assess the impacts of crop species, climatic conditions, stand composition and nitrogen fertilisation on Ndfa. The global meta-analysis reveals that the percentage of nitrogen derived from atmospheric fixation (Ndfa) in legumes ranges from 5% to 99%, with an average of 68%. Fodder legumes exhibited higher Ndfa, averaging 75%, while grain legumes showed more variability, ranging from 38% to 85%, depending on species and climatic conditions. The significant variability in Ndfa underscores the complexity of the process, which is influenced by species-specific traits, ecological conditions and competition in mixed stands. However, the current data is insufficient for precise Ndfa estimation in nitrogen balances and decision support tools. The study highlights the need for further research on the impact of nitrogen fertilisation and stand composition on Ndfa. These findings emphasise the potential of BNF to support sustainable agriculture by improving nitrogen availability and reducing dependence on synthetic fertilisers and particularly susceptibility to climate change challenges. To optimise the benefits of BNF, future research should focus on refining fertilisation regimes and exploring species-specific responses to various ecological conditions. Exploring adaptive strategies, like selecting drought-tolerant legumes and optimising irrigation, is essential. This will enhance the application of BNF in diverse agricultural systems, contributing to more sustainable and efficient farming practices.

Ridge–furrow cropping patterns, nitrogen fertilisation and seed rate regulation are popular management strategies for improving crop yields in the semi-arid areas of Northwest China, but their interactive effects on grain yield and water use efficiency remain poorly understood. In 2020–2021 and 2021–2022, a two-season field experiment was conducted on winter wheat. There were two cropping patterns (C), ridge–furrow cropping with film mulch (RC) and traditional cropping without mulch (TC), two nitrogen fertilisation rates (N), 0 and 200 kg N ha⁻¹ (N₀ and N₁) and three seed rates (S), 240, 360 and 480 plants m⁻² (S₁, S₂ and S₃). The study was conducted in a split–split design with three replications (randomised blocks) and a total of 24 experimental plots. It was found that the interactive effects of C × N, C × S and N × S were significant on soil temperature (ST), leaf area index (LAI), relative chlorophyll content (SPAD), photosynthetic parameters, grain yield (GY) and water use efficiency (WUE) (p < 0.05), while C × N × S was significant only for LAI, aboveground biomass (AGB), GY and WUE (p < 0.05). Compared with TC and N₀, RC and N₁ significantly increased SPAD value (2.4% and 15.8%), net photosynthetic rate (P_n) (19.8% and 32.8%), net photosynthetic rate (P_n), transpiration rate (T_r) (7.0% and 15.7%) and the effective PSII quantum production (ΦPSII) (10.7% and 5.0%). The highest GY (6773 kg ha⁻¹ over 2020–2021 and 8036 kg ha⁻¹ over 2021–2022) and WUE (20.03 kg ha⁻¹ mm⁻¹ over 2020–2021, and 21.77 kg ha⁻¹ mm⁻¹ over 2021–2022) of winter wheat were observed under RC + N₁ + S₂. The findings showed that the RC cropping pattern with fertilisation and seed rate regulation (360 plants m⁻²) of winter wheat, which is appropriate for ensuring the long-term sustainability of agricultural production in the semi-arid regions of Northwest China, enhanced plant growth, photosynthetic traits, yield and water use efficiency. The study might give useful information for enhancing the productivity and water use efficiency of winter wheat in this and other similar climate locations.

Antioxidant enzymes in plants are critical for protection against oxidative stress and for the overall health and resilience of plant systems. However, antioxidant responses of plants grown in shallow and saline groundwater are poorly understood. Therefore, understanding the biochemical responses of plants to shallow groundwater significantly affects food security and environmental conservation. With this aim, the present work was carried out for 2 years in drainable lysimeters to assess the effects of four different groundwater salinities (0.38, 2.0, 4.0 and 8.0 dS m⁻¹) on the temporal changes in antioxidant enzymatic activity in wheat plants under three different groundwater depths (30, 55 and 80 cm). Superoxide dismutase (SOD), glutathione S-transferase (GST) and catalase (CAT) activities varied significantly based on groundwater depth and salinity. CAT and GST enzyme levels increased curvilinearly with rising groundwater depth and salinity. Conversely, the GR enzyme activity showed no significant change with groundwater depths but increased linearly with higher salinity. SOD enzyme activity notably increased at a groundwater depth of 30 cm but decreased at a depth of 80 cm. Moreover, the peak activity of the GR enzyme was observed at a 6 dS m⁻¹ groundwater salinity under groundwater depths. Additionally, the GST and CAT enzyme activities were inhibited more when the groundwater depth was <55 cm and the groundwater salinity was >4.20 dS m⁻¹. Finally, identifying the peak levels of antioxidant enzymes could potentially serve as an indicator for determining the optimal timing for applying stress mitigation methods in areas with shallow and saline groundwater.