Rapeseed (Brassica napus L.) is often grown under high nitrogen (N) fertilization, increasing the risk of N losses and associated environmental impacts. Using a systematic literature search of Web of Science and Google Scholar (1995-2024) and predefined inclusion criteria, we synthesized 106 field studies to quantify rapeseed yield, nitrogen-use-efficiency (NUE), agronomic efficiency of nitrogen (AEN), and environmental responses to N rate. Across studies, yield responded nonlinearly to N, with rapid gains at low-moderate rates and diminishing returns thereafter; a linear-plus-plateau (LPP) fit indicated yield stabilization around ∼200-225 kg N ha−1 (mean yield ≈2.22 Mg ha−1). Region-specific dose-response functions showed distinct yield-maximizing tendencies: Asia (∼150), Australia (∼125), Europe (∼160-170), and an earlier saturation signal in North America. Both NUE and AEN declined consistently as N rate increased, with greater dispersion and a steeper efficiency erosion in developing-country datasets than developed-country datasets. Environmental context significantly modified the yield-N relationship: mean annual precipitation (MAP), soil pH, and soil organic matter (SOM) shifted response curvature and implied N optima, while yields were highest under intermediate precipitation (500-1000 mm), near-neutral pH (≈6.5-7.5), and higher SOM. Environmental indicators increased disproportionately at higher N supply: N2O and CH4 followed significant nonlinear trends, and soil NO3−-N and NH4+-N pools rose markedly under fertilized treatments. Integrating diminishing yield gains with accelerating environmental costs supports a balanced N management window of ∼100-150 kg N ha−1 for many systems, with rates above ∼150-200 kg N ha−1 requiring clear, site-specific justification and mitigation (e.g., split/variable-rate application, enhanced-efficiency fertilizers, and SOM-building soil management). This framework offers actionable pathways to reconcile agricultural productivity with environmental sustainability.

Soil salinization is a major environmental hazard, hindering rapeseed development due to sodium ion (Na+) toxicity and ionic imbalances in plant cells. Understanding tolerance mechanisms and categorizing reliable physiochemical indicators is vital for enhancing rapeseed tolerance. Herein, we aimed to enhance knowledge about the stress-responsive mechanism of ten rapeseed varieties (C71, C88, C91, C97, C123, C136, C196, C272, C280, and C320) exposed to five NaCl concentrations (0, 150, 200, 250, and 300 mM) through determining key factors related to salt tolerance at the seedling stage. Our results showed that salt stress significantly reduced seedling growth and biomass with increasing salt stress concentration in a similar pattern in all studied varieties, especially in sensitive seedlings. Furthermore, photosynthetic pigment, osmotic solutes, and MDA showed significant variations under salt treatment versus control in all studied varieties. Based on morpho-physiochemical trait analysis of ten rapeseed varieties, C71 and C272 were selected as tolerant and sensitive varieties to study stress responses during six weeks (weekly time points) in the leaf, petiole, stem, and root of seedlings under 250 mM NaCl. Current findings demonstrated superior osmotic adjustment of C71 through higher accumulation of total soluble sugars and protein, reflected in lower MDA levels, which contributed to maintaining cellular homeostasis and membrane integrity to improve resilience under salinity versus C272. Besides, total amino acid content was enhanced in C71 versus C272 seedlings, which was attributed to stress tolerance. In different tissues of C71 and C272, Na+ and K+ levels varied with increasing growing time, reaching the maximum increment at the 6th week under salt stress conditions. Moreover, Na+ initially accumulates in roots and enhances the K+ level in tolerant seedlings; besides, K+ was accumulated higher in the roots of tolerant seedlings, resulting in K+ homeostasis, thereby improving stress tolerance. Our results can be a great reference value for rapeseed plant breeders to develop salt-tolerant cultivars.

The rhizosphere microbiome underpins plant nutrition, health, and stress resilience, making it central to sustainable agriculture. Although soil physicochemical properties and environmental variability shape microbial communities, converging evidence shows that specific microbial taxa repeatedly associate with particular plant genotypes. This host-dependent stability implies that plant genomes impose selective filters on microbial assembly through root exudation, immunity, and developmental traits. This review outlines a mechanistic framework that partitions rhizosphere microbiome assembly into two components: (i) an environment-driven microbiome shaped predominantly by edaphic conditions, climate, and management practices, and (ii) a host genetics-driven microbiome structured by plant molecular and physiological determinants. We aim to disentangle the assembly rules governing each component and assess their potential for targeted manipulation in crop improvement. The environment-driven component arises from microbial responses to nutrient availability, pH, moisture (including drought and salinity-driven osmotic/ionic stress), and agronomic inputs, and is dominated by ecological filtering and resource competition. The host-genetics-driven component arises from genotype-specific traits, including root architecture, exudate chemistry, and immune signaling pathways, that modulate colonization and persistence. This distinction highlights complementary leverage points: agronomic strategies to steer environment-driven processes and genetic dissection of loci controlling microbial recruitment. Major challenges include strong context dependency across soil–genotype combinations, limited power to link plant alleles to microbiome functions, and the lack of predictive models integrating host genetics, environment, and microbial dynamics. A dual-strategy environmental optimization, combined with breeding to enhance the recruitment of beneficial microbes, offers a tractable route to microbiome-informed crop improvement and more resilient production systems.

Salinity stress severely impacts agricultural productivity by inhibiting seed germination in rice. Finding plant-derived products that can improve germination under salinity stress offers an environment-friendly approach. This study investigates the protective role of exogenous sulforaphane (SFN) in enhancing rice seed germination under salinity stress. We compared the responses of salt-sensitive (LLY-7108) and salt-tolerant (G-16) rice varieties to determine the effectiveness of SFN treatment with 150 mM NaCl stress, where LLY-7108 showed significantly higher germination inhibition under salt stress compared to G-16, while SFN application notably improved germination rate of LLY-7108 with minimal effects on G-16. Our investigation revealed that salt stress increased Na+ accumulation and Na+/K+ ratio in rice seeds, leading to elevated levels of reactive oxygen species (H2O2, O2-) and malonaldehyde (MDA). This ionic imbalance disrupted hormone homeostasis, decreasing gibberellic acid (GA) while increasing abscisic acid (ABA) levels, and inhibited α-amylase activity, thereby reducing starch hydrolysis. SFN treatment effectively mitigated these adverse effects by enhancing OsHKT1;1 and OsHKT1;5 expressions, which reduced Na+ uptake and improved ion balance. Additionally, SFN enhanced antioxidant enzyme activities (superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT), regulated ABA biosynthesis genes (OsNCED1, OsNCED3), improved α-amylase activity, and increased soluble sugar content; besides it improved the cell ultrastructure and chloroplast structure versus salt treatment. These findings highlight SFN's protective role in rice germination under salinity stress through ion homeostasis regulation, reactive oxygen species (ROS) scavenging, hormone balance restoration, and enhanced starch metabolism. SFN offers a practical solution for improving direct-seeded rice germination in saline soils.

Understanding tolerance mechanisms and categorizing reliable physiochemical indicators related to their mechanisms is important for enhancing rapeseed tolerance and sustainable agricultural development. Putrescine (Put), one of the important polyamines, plays a promising role in promoting the synthesis of bioactive compounds related to plant development, especially under stress conditions. Herein, the potential role of Put in alleviating salt stress in rapeseed has been thoroughly investigated via priming application with different concentrations (0.1, 0.3, 0.5, 0.7, and 1 mM). Seed germination-related parameters and hormone-related genes were studied during seed imbibition under 150 mM of NaCl. Additionally, morpho-physiochemical characteristics, ionic content, and ion exchange-related genes were investigated in the shoots and roots of 7-day-old seedlings under salinity stress. Our results showed that Put-priming improved germination parameters by regulating seed germination and hormone-related genes under salinity stress, especially at 0.3 and 0.5 mM Put, compared with unprimed and hydroprimed (HP) seeds. Besides, it significantly enhanced seedling growth by preventing the degradation of photosynthetic pigments and modulating the proline and soluble solute accumulation in shoots and roots. Moreover, MDA, H2O2, and O2 contents decreased with Put-priming, especially at 0.5 mM, indicating the significant role of Put in ROS scavenging and inhibiting lipid peroxidation upon stress. Put-priming alleviated salt-induced oxidative stress by enhancing the structure and function of the enzymatic and non-enzymatic antioxidative systems, which protect the integrity of cellular membranes in seedlings under stress conditions. Our study observed increased Na+ and decreased K+ contents under salt treatments versus control (Ctrl), whereas Put treatments not only reduced Na+ but also increased K+ accumulation, lowering the Na+/K+ ratio, especially at 0.3 and 0.5 mM Put versus unprimed and HP seedlings. Put-priming showed strikingly stronger effects on intracellular Na+ and K+ homeostasis by regulating ion exchange-related genes, which upregulated the gene expression of BnH+-ATPase, BnNHX6, BnSOS1, BnSKOR, BnHKT1, and BnHKT8 that modulated Na+ influx and K+ efflux under salinity stress. Our results provide an integrative understanding and scientific basis for the exogenous application of Put as a promising method for improving salt tolerance in rapeseed seedlings at morpho-physiochemical and molecular levels, which provides a convenient, fast, and environmentally friendly strategy to help crops adapt to be used for cultivation in saline soil.

Salt stress impairs plant growth by disrupting osmotic regulation, ion homeostasis, and oxidative stress management. Plants respond by activating defense mechanisms, including the biosynthesis of secondary metabolites (SMs) such as alkaloids, flavonoids, terpenoids, and glucosinolates (GSLs). Calcium (Ca2⁺) signaling is central to these responses, acting as an early stress signal. Ca2⁺ influx triggers calcium-dependent protein kinases (CDPKs) and other signaling molecules, which activate stress-responsive genes. SMs are pivotal in mitigating salt stress by promoting osmotic adjustment, maintaining cellular turgor, and modulating ion transporters to reduce Na⁺ uptake and enhance K⁺ retention. This ion homeostasis is closely regulated by Ca2⁺ signaling, which influences transport proteins like Na⁺/K⁺ transporters and vacuolar calcium exchangers (e.g., OsCAX1). The crosstalk between SMs and Ca2⁺ exhibited a critically important role in salt tolerance, as Ca2⁺ influx is an essential trigger for calcium-dependent signaling pathways. Additionally, Ca2⁺ signaling regulates the biosynthesis of SMs through transcription factors like MYB and WRKY. These SMs help detoxify reactive oxygen species (ROS) by regulating antioxidant enzymes such as superoxide dismutase (SOD) and catalase (CAT), aided by MAPK signaling cascades. SMs also interact with abscisic acid (ABA) signaling to regulate stomatal closure and stress-related gene expression, enhancing the plant’s resistance to salt stress. Recent meta-QTL analysis has identified key loci involved in SM biosynthesis and Ca2⁺ signaling pathways under saline conditions, providing promising targets for breeding salt-tolerant crops. This review explores the molecular mechanisms and regulatory networks of SMs and Ca2⁺ signaling in plant salt stress responses, with potential applications in sustainable agriculture.

Soil salinity, a critical environmental stressor, substantially impacts plant growth and productivity. It induces osmotic stress, disrupts ion homeostasis, and triggers the excessive production of reactive oxygen species (ROS), which can lead to oxidative damage within plant cells. To counteract these detrimental effects, plants have evolved sophisticated defense mechanisms, one of which involves the production of secondary metabolites (SMs). These SMs function as biostimulants that bolster antioxidative defenses and modulate signal transduction pathways, thus enhancing the plant's tolerance to salt stress. Recent evidence reveals SMs like sulforaphane (glucosinolate-derived) uniquely stabilize redox cofactors and reprogram stress-responsive miRNAs. Furthermore, they influence key signaling cascades, such as the mitogen-activated protein kinase (MAPK) pathway and various hormone-regulated pathways, which are instrumental in orchestrating adaptive responses to saline conditions. The regulation of SMs biosynthesis under salt stress is mediated by transcription factors like MYB, WRKY, and bHLH, which are essential for activating the genes involved in these metabolic pathways. Elucidating the intricate mechanisms by which SMs operate as biostimulants not only advances our understanding of plant stress responses but also paves the way for developing sustainable agricultural practices aimed at improving crop resilience in saline environments. This knowledge is instrumental for cultivating crops that can thrive under challenging soil conditions, ultimately contributing to global food security.

Traditional crop breeding techniques are not quickly boosting yields to fulfill the expanding population needs. Long crop lifespans hinder the ability of plant breeding to develop superior crop varieties. Due to the arduous crossing, selecting, and challenging processes, it can take decades to establish new varieties with desired agronomic traits. Develop new plant varieties instantly to reduce hunger and improve food security. As a result of the adoption of conventional agricultural techniques, crop genetic diversity has decreased over time. Several traditional and molecular techniques, such as genetic selection, mutant breeding, somaclonal variation, genome-wide association studies, and others, have improved agronomic traits associated with agricultural plant productivity, quality, and resistance to biotic and abiotic stresses. In addition, modern genome editing approaches based on programmable nucleases, CRISPR, and Cas9 proteins have escorted an exciting new era of plant breeding. Plant breeders and scientists worldwide rely on cutting-edge techniques like quick breeding, genome editing tools, and high-throughput phenotyping to boost crop breeding output. This review compiles discoveries in numerous areas of crop breeding, such as using genome editing tools to accelerate the breeding process and create yearly crop generations with the desired features, to describe the shift from conventional to modern plant breeding techniques.

Climate change adversely affects the pattern of temperature and distribution of rainfall, due to which sowing of wheat is delayed from mid-October to early December. This consequently lowers the quality of wheat crop. A study was carried out on grain quality, biochemical traits, and internal water status of elite Chinese wheat lines according to sowing interval under semiarid conditions during the winter season 2020–2021. The experimental design was randomized complete block with a split-plot arrangement and three replications. Treatments consisted of sowing date (1 November, 16 November, and 1 December 2020) and wheat lines (MY409‑4, MY1617, MY1416, MY291‑4, MY1501, MY1419, and MY902) with one local wheat check (PS-15). Sowing dates were assigned to the main plot and wheat lines to the subplot. Results indicated that wheat lines MY291‑4, MY409‑4, and MY902 resulted in higher chlorophyll content (54.7 SPAD value), carotenoids (11.7 mg g−1), grain protein content (12.8%), and amylose content (25.5%), with statistically similar values between the lines. Similarly, lines MY291‑4 and MY902 resulted in higher relative water content (78.6%) and wet gluten content (29.1%), statistically on par with each other, while the proline (43 mg g−1) and amylopectin contents (79.0%) were higher in local check PS-15. Moreover, water saturation deficit (30.3%) and dry gluten content (11.5%) were higher in line MY409‑4. Regarding sowing dates, sowing on 1 November resulted in maximum chlorophyll content (53.0 SPAD value), carotenoids (10.8 mg g−1), relative water content (76.2%), amylose content (24.3), wet gluten content (27.7%), and dry gluten content (11.4%) as compared to late sowing on 1 December, while water saturation deficit (27.9%), proline content (39.8 mg g−1), grain protein content (12.6%), and amylopectin content (77.9%) were higher with late sowing on 1 December. Conclusively, wheat lines MY291‑4, MY409‑4, and MY902 produced higher chlorophyll content, carotenoids, relative water content, water saturation deficit, grain protein content, amylose content, and wet and dry gluten content, while proline and amylopectin contents were higher in local cultivar PS-15. Likewise, plots sown earlier on 1 November resulted in increased in chlorophyll content by 7%, carotenoids by 17%, relative water content by 9%, amylose content by 10%, wet gluten content by 9%, and dry gluten content by 16% as compared to late sowing on 1 December, while water saturation deficit, proline content, grain protein content, and amylopectin content were 18%, 7%, 14%, and 8% higher than with early sowing on 1 November, respectively.

A field experiment was carried out at The Agronomy Research Farm, The University of Agriculture Peshawar, during rabi season 2020–2021 to evaluate levels of rock phosphate (100, 200, 300, 400 and 500 kg ha−1) and two consortium of phosphorus solubilizing bacteria including PSBc1 (Pantoea sp., Klebriella sp., Brevibacterium sp., Acinetobacter sp.) and PSBc2 (Cellulomonas sp., Alcaligenes sp. Pseudomonas sp.) on growth and yield components of chickpea variety Karak 1. The experiment was laid out in randomized complete block design with rock phosphate in main plot and phosphorus solubilizing bacteria in subplot. The analyzed data revealed that there was non-significant effect of the treatments on days to emergence. Emergence m−2 was significantly affected by phosphorus solubilizing bacteria while the impact of rock phosphate was non-significant. Physiological maturity showed significant response to rock phosphate while effect of phosphorus solubilizing bacteria was non-significant. Besides that, all other parameters including days to flowering appearance, nodules per plant, nodules weight per plant, plant height, number of pods per plant, seeds per pod, 1000-seed weight, biomass and grain yield were significantly affected by rock phosphate levels and phosphorus solubilizing bacteria except harvest index in which the effect of phosphorus solubilizing bacteria was non-significant. To sum up, the results show that rock phosphate application at the rate of 500 kg ha−1 enhanced days to flowering appearance (104), days to physiological maturity (152) increased nodules plant−1 (25), nodules weight plant−1 (1.86 g), plant height (59 cm), number of pods plant−1 (49), seeds pod−1 (1.79), 1000-seed weight (231 g), biomass (5507 kg ha−1), grain yield (1899 kg ha−1) and harvest index (34.48