Phenotypic, hydroponic performance assessment, and expression profiling of triple knockout negative regulator genes in rice (Oryza sativa L.)

PGPR-induced regulation of Zn and Fe transporters in wheat (Triticum aestivum L.) uncovered through integrated genome-wide analysis and functional validation.

Zinc (Zn) and iron (Fe) deficiencies affect more than two billion people globally, particularly in cereal-dependent regions where wheat, despite its high consumption, provides inadequate micronutrient levels. Conventional interventions such as genetic modification and mineral supplementation remain costly, unevenly accessible, and insufficient for large-scale nutritional improvement. Agronomic biofortification using plant growth-promoting rhizobacteria (PGPR) offers a promising yet underexplored alternative, especially for regulating metal homeostasis genes in wheat. This research integrates multi-season field trials of Zn-biofortified Akbar-19 and the local cultivar Khaista-17, conducted under reduced fertilizer conditions with PGPR consortia. Afterwards, genome-wide analyses including phylogenetic relationships, promoter elements, gene interaction networks, expression profiles, and conserved domains/motifs of the TaNAS (19 genes), TaNAAT (6), TaDMAS (3), and TaVIT (31) gene families was performed. This was followed by transcriptional expression (qPCR) of six candidate genes in wheat grown under hydroponic Zn/Fe stress in the presence of PGPR. Field evaluation showed that PGPR inoculation boosted yield by 15-18% and increased grain Zn/Fe by 15-20% in Akbar-19 and 25-28% in Khaista-17, consistently outperforming fertilizer-only controls across both seasons. The genome-wide analyses exhibited the phylogenetic relationship of wheat TaDMAS, TaNAAT, and TaNAS genes with barley, while TaVIT and TaVTL genes with rice and maize. Promoter analyses of these genes showed an enrichment of stress-responsive cis-elements, such as IDE1/2, ZDRE1/2, IRO2-binding sites, and metal-responsive elements suggesting coordinated regulation of micronutrient chelation, uptake, and homeostasis. qPCR results confirmed PGPR-induced upregulation of NAS1, NAS6, NAS9, NAAT2, DMAS1, and VIT2 under Zn/Fe stress, with stronger induction in Khaista-17. Overall, the results show that PGPR modulate metal‑transporter gene networks and improve micronutrient biofortification in wheat, providing a genotype‑responsive and sustainable approach to address micronutrient deficiency.

Elucidating the Growth-Promoting Mechanism of Bacillus safensis in Nipponbare Rice Through Integrated Phenotypic and Transcriptome Analysis.

A growing global demand for rice necessitates improvements in grain productivity to support sustainable agricultural developments. Bacillus safensis, a halophilic soil bacterium, has been shown to enhance crop growth, but its effects on rice (Oryza sativa L.) remain unclear. In this study, we tested how B. safensis affects rice yields and agronomic traits. We applied B. safensis to roots and panicles of rice and measured plant height, tiller number, panicle length, panicle weight, grain number per panicle, 1000-grain weight, grain setting rate and theoretical yield. The results showed that root treatment and root-panicle co-treatment increased theoretical yield by 4.33% and 2.78%, respectively, accompanied by significant improvements in plant height, tiller number, panicle length, and grain number per panicle. RNA-seq analysis revealed shifts in gene expression and alternative splicing associated with these agronomic improvements. KEGG pathway analysis showed B. safensis treatment regulated genes involved in stress tolerance, metabolic regulation, and secondary metabolite production. Field experiments further demonstrated that B. safensis application significantly increased tiller number, grain number per panicle, 1000-grain weight and grain setting rate, leading to an 8.98% increase in theoretical yield. Overall, this study suggests B. safensis is a promising biostimulant for sustainable rice farming and provides a reference for the application of B. safensis in rice production.

Disruption of OsGONST3 reduces grain cadmium accumulation without yield penalty in field-grown rice.

Cadmium (Cd) pollution in paddy soils threatens global food safety. Identifying molecular gateways controlling grain Cd accumulation is essential for breeding low-Cd rice. A field-based screen of a large-scale CRISPR/Cas9 mutant library identified OsGONST3, a Golgi nucleotide sugar transporter family member localized to the plasma membrane. After 1 μM Cd treatment for 7 d, OsGONST3 transcript abundance increased approximately 3.4-fold in root and 5.7-fold in shoot, accompanied by increased OsGONST3-GFP protein accumulation. Heterologous OsGONST3 expression increased yeast Cd content by approximately 23% relative to the empty-vector control. Under hydroponic exposure to 1 μM Cd for 7 d, two independent osgonst3 mutants contained 22-25% less Cd in root, approximately 13% less in shoot, and 16-21% less in xylem sap than Nipponbare. Conversely, OsGONST3-overexpressing lines contained 40-42%, 38-40%, and 28-37% more Cd in root, shoot, and xylem sap, respectively. Under tested field condition, OsGONST3 disruption reduced grain Cd by approximately 25-26% without a significant yield penalty and was associated with secondary transcriptional adjustments in Cd-homeostasis genes. These findings identify OsGONST3 as a plasma membrane-localized Cd influx-associated protein and a promising target for breeding low-Cd rice.

MicroRna268-Mediated Zinc Homeostasis in Rice (Oryza Sativa L.): Enhancing Growth and Yield Under Different Methods and Timing of Zinc Fertilizer Application

ABSTRACT Micro-RNA268 (miR268) plays an important role in modulating plant responses to different types of biotic and abiotic stresses. Zinc (Zn) has an essential physiological role in plants and is often deficient in crops. A study was conducted under controlled lowland (flooded) rice cultivation conditions to investigate the potential role of miR268 overexpression in modulating rice seedling resilience and yield in response to foliar Zn application. The rice seedlings were exposed to different Zn supplementation treatments: control (without zinc application), root dipping of seedlings in 0.5% zinc solution, basal application (30 kg ha−1), and foliar applications of Zn (0.5%) at 30, 45, 60, 75, and 90 days of transplantation. Different parameters such as growth characteristics, chlorophyll content, and yield metrics were systematically evaluated post-harvest. The study demonstrated that miR268 overexpression enhanced Zn uptake, with foliar Zn application (90 days) yielding the highest chlorophyll content (1.85%) and lowest oxidative stress (malondialdehyde, MDA: 1.25 nmol g−1 fresh weight, FW). Basal Zn application resulted in maximal Zn accumulation (roots: 29.6 µg g−1 dry weight, DW; shoots: 37.5 µg g−1 DW) and a 15.5% increase in 1000-kernel weight. These findings confirm miR268‘s central role in Zn homeostasis: foliar Zn at 90 days was most effective for enhancing photosynthesis and reducing oxidative stress, whereas basal application was superior for maximizing Zn accumulation and grains weight. Therefore, the optimal method depends on the target outcome, foliar application for stress protection or basal application for yield improvement-thus providing flexible management for Zn-deficient soils.

The free amino acid-rich biostimulant, Leafamine®, promotes cell division in tomato roots and alleviates heat stress effects

The COBRA-Like9 from Glycine tabacina enhanced salt tolerance in cultivated soybean