OsCYP51H9 integrates brassinosteroid biosynthesis and nitrogen sensing to enhance grain development and nitrogen utilization in rice.

StuPPO9 Enhances Drought Tolerance in Potato (Solanum tuberosum) by Coordinating Photosynthetic Stability and Secondary Metabolism Reprogramming

Drought stress is a primary abiotic constraint limiting potato productivity. While polyphenol oxidase (PPO) is known to participate in stress responses, the specific role of StuPPO9 in drought tolerance remains poorly understood. In this study, we generated StuPPO9-overexpressing (OE) and CRISPR/Cas9-mediated knockout (C4) lines in the potato cultivar ‘Atlantic’. Under sustained drought stress, OE lines exhibited significantly superior growth phenotypes compared to wild-type (WT) and C4 plants, characterized by increased leaf and root relative water content, root number and enhanced photosynthetic efficiency (Pn and Gs). OE plants also maintained lower levels of MDA and ROS through elevated antioxidant enzyme activities. Notably, transcriptomic analysis revealed that StuPPO9 triggers a global reprogramming of metabolic pathways. Key drought-responsive genes associated with phenylpropanoid biosynthesis (e.g., anthocyanin acyltransferase), terpenoid metabolism, and hormone signaling (e.g., HPt protein) were significantly upregulated in OE plants. These findings suggest that StuPPO9 confers drought resilience through a multi-layered network involving optimized carbon allocation, reinforced cell wall integrity, and enhanced ROS scavenging capacity. This study provides a promising genetic target and theoretical foundation for breeding drought-resistant potato varieties.

OsDUF3615 regulates grain size and quality traits by modulating cell proliferation and starch metabolism in rice

Domains of Unknown Function (DUFs) are widely distributed across diverse genomes and are increasingly recognized as important regulators of plant growth, development, and stress responses. DUF3615 is a highly conserved plant-specific protein motif; however, its biological function remains largely unknown. Previously, the gene OsGAPC3 , a key regulator of grain quality, was isolated and functionally characterized in rice. Transcriptome analysis during the dissection of the OsGAPC3 -mediated regulatory pathway revealed that OsDUF3615 is significantly upregulated in Osgapc3 mutants, suggesting its potential involvement in rice development and grain traits. In this study, we show that OsDUF3615 is constitutively expressed in rice and encodes a nucleus-localized protein. Functional analysis demonstrated that overexpression of OsDUF3615 significantly promotes cell proliferation and expansion in the lemma along the grain width axis, leading to increased grain width and thousand-grain weight. Moreover, OsDUF3615 modulates grain filling dynamics and alters the accumulation of major storage compounds, including starch and free fatty acids, thereby affecting both nutritional composition and eating quality traits, such as taste value. Collectively, our findings identify OsDUF3615 as a key regulator of rice grain development and quality formation, providing valuable genetic resources for the molecular breeding of high-quality rice varieties.

Unveiling GmCS1 Promote Branch Development by Regulating Plant Hormones in Soybean

Soybean (Glycine max (L.) Merr.) was originally domesticated in China and is a kind of significant leguminous crop, which can fix atmospheric nitrogen to bioavailable nitrogen in association with rhizobia. Ceramides, intermediates of sphingolipids, are crucial structural components in membrane formation and also function as signaling molecules, which play crucial roles in plant development and defense. Although Arabidopsis ceramide synthase genes AtLOH1 and AtLOH3 overexpression plants increased biomass compared to the wild type, the potential mechanism in plant growth was still unclear. A soybean ceramide synthase gene 1 (GmCS1) has a high expression level in the stem, and the protein is localized in the endoplasmic reticulum. Overexpression of GmCS1 promotes soybean lateral branch development for effective branch formation, significantly increasing the number of lateral branches and pods. Using transcriptomic profiles, we found that GmCS1 overexpression lines displayed the upregulation of plant hormone signal transduction pathway gene expression in developmental branches. Actually, Indole-3-acetic acid (IAA) induces bud outgrowth rather than initiation according to the determination of endogenous IAA and cytokinin (CKs) in soybean lateral branches. Collectively, these results suggest that GmCS1 may be a functional ceramide synthase gene in soybean, with the GmCS1-mediated regulatory network playing a crucial role in controlling branch development by IAA and CKs homeostasis. Exploring the regulation mechanisms by GmCS1 overexpression lines is essential for Ideal Soybean Architecture (ISA) innovation.

Nitrogen Deficiency Outperforms Water Stress in Triggering Strigolactone‐Dependent Responses in Maize

ABSTRACT Strigolactones (SLs) modulate multiple aspects of plant development and stress physiology. This study investigated their role in maize response to abiotic stress by comparing an SL‐biosynthesis mutant (zmccd8) with wild‐type (WT) seedlings grown for 4 weeks in vermiculite under nutrient and water limitation. Plant growth, time‐course pigment accumulation, targeted gene expression, and root transcriptomic profiles were analyzed. Our results showed that zmccd8 plants were largely unable to induce leaf senescence and efficient nutrient remobilization toward younger tissues under nitrogen (N) deficiency, a response previously associated with maize adaptation to low N availability. In parallel, the mutant developed a smaller root system, mainly due to limited adventitious root formation, particularly under N shortage. Root transcriptomic profiling revealed that N deficiency strongly affected WT plants, inducing extensive regulation of pathways involved in nitrogen metabolism and transport, secondary metabolism, ethylene and MAPK signaling, oxidative stress responses, and major transcription factor families. These responses were largely absent in the zmccd8 mutant, suggesting reduced transcriptional plasticity and compromised capacity to cope with stress‐associated oxidative imbalance. Conversely, despite inducing substantial physiological and molecular responses, water stress elicited only modest SL‐dependent regulation, with limited and heterogeneous changes between genotypes. Overall, our findings demonstrate that in maize, SLs act in a stress‐specific manner, playing a predominant role in acclimatisation to nitrogen deficiency through coordinated regulation of senescence, nutrient remobilization, root architecture, and gene expression, while contributing more marginally to water‐stress acclimatisation. These results provide new insights into SLs' role in shaping maize physiological plasticity under abiotic stress conditions.

GmHMGR6 enhances salt stress tolerance in soybean through modulation of nitrogen metabolism

These findings demonstrate that GmHMGR6 enhances soybean salt tolerance through coordinated regulation of nitrogen metabolism, nodulation, and photosynthetic performance.

NtWHY1 negatively regulates tobacco cold tolerance via interfering with flavonoid biosynthesis