Plant Physiology and Biochemistry最新文献

Plant male sterility (MS) is a fundamental model for studying reproductive development, yet a critical but often overlooked distinction exists between sporophytic male sterility (SMS) and gametophytic male sterility (GAMS). Unlike SMS, which is controlled by the sporophyte's genotype, GAMS is uniquely determined by the gametophyte's own genome, leading to subtle phenotypes that are challenging to identify. Here, we systematically classify 59 identified GAMS genes in Arabidopsis, rice, and maize into three functional categories based on their defective phenotypes during pollen development: Pollen Maturation Defects (PMD), Pollen Germination Defects (PGD), and Male-Female Communication Defects (MFCD). Leveraging the evolutionary conservation of these pathways, we employed a comparative genomics approach to identify 18 high-confidence candidate GAMS genes in maize. Functional validation of ZmCESA6 as a PGD-type GAMS gene confirms the effectiveness of our strategy. This study provides a comprehensive functional map of GAMS and offers valuable genetic resources for hybrid breeding in major crops.

Aspartic proteases represent a class of proteolytic enzymes widely implicated in plant growth regulation and abiotic stress responses. Our previous work identified an aspartic protease, GmAP1, whose expression is strongly correlated with flowering time in wild soybean populations. In this study, we further demonstrated that GmAP1 overexpression (OE) significantly delays flowering, whereas CRISPR/Cas9-mediated knockout (CR) accelerates this process. Specifically, OE lines exhibited suppressed expression of CONSTANS (CO) and FLOWERING LOCUS T (FT), along with elevated transcript levels of FLOWERING LOCUS C (FLC). Subcellular localization assays confirmed that GmAP1 is targeted to chloroplasts, where it downregulates the PHD-type transcription factor gene PTM without affecting GOLDEN2-LIKE 1/2 (GLK1/2). Notably, GmAP1 expression was strongly induced by salt stress. GmAP1-OE lines exposed to salt stress showed chlorophyll degradation and reduced net photosynthetic rate (Pn). Both in vivo and in vitro biochemical assays verified that GmAP1 interacts with and degrades the Rubisco large subunit (rbcL), a process correlating with decreased Pn and delayed flowering in OE lines under salt stress. Collectively, our findings reveal that GmAP1 coordinates photosynthetic energy supply and reproductive transition in soybean. Precise modulation of this gene holds substantial practical value for developing early-maturing, salt-tolerant soybean varieties well adapted to saline-alkali environments.

The extensive use and improper disposal of plastics have led to the accumulation of plastic debris in terrestrial ecosystems, where plastics gradually degrade into microplastics (MPs) and nanoplastics (NPs). While MPs are pervasive contaminants, NPs present greater agricultural risks due to their ultra-small size, high surface area, and colloidal stability, which enable them to enter plant tissues and threaten plant health and crop productivity. However, the underlying mechanisms remain unclear. This review aims to summarize recent advances in understanding NP uptake, translocation, and physiological impacts on crops, and to evaluate key tracking technologies. We highlight that NPs' behavior in plants is influenced by particle properties, cultivation systems, and plant traits. Fluorescence imaging and isotope labeling are effective for tracking NPs in plant systems. NPs enter plants primarily through root and foliar pathways, interfering with nutrient acquisition, hormone signaling, and oxidative stress responses, thereby affecting plant growth and development. By synthesizing current knowledge on NP-plant interactions, this review provides a timely overview to guide future research toward understanding the environmental fate and ecological risks of NPs in agricultural systems, ultimately supporting the sustainable development of modern agriculture.

This study investigated the mitochondrial response mechanisms of Syntrichia caninervis Mitt., a desiccation-tolerant moss from the Chinese Gurbantunggut Desert, to dehydration-rehydration stress at the subcellular level under three dehydration intensities: rapid drying (RD), slow drying (SD), and air drying (AD). The results showed that the moss maintained the structural integrity of mitochondrial membranes across treatments, demonstrating remarkable phenotypic plasticity. Rapid dehydration caused a pronounced decline in mitochondrial membrane potential (ΔΨm) and distortion of cristae, relying primarily on emergency antioxidant responses involving superoxide dismutase (SOD) and ascorbate peroxidase (APX) to scavenge reactive oxygen species (ROS). In contrast, slow dehydration activated a "pre-adaptive" antioxidant strategy characterized by sustained peroxidase (POD) activation, accumulation of reduced glutathione (GSH), and upregulation of alternative oxidase (AOX) activity. Principal component analysis confirmed that APX, SOD, and AOX were key contributors to drought adaptation. This study is the first to reveal dual-track adaptive mechanisms in desiccation-tolerant plants mediated through mitochondrial ultrastructure, membrane potential dynamics, and redox homeostasis regulation, and provides new targets for improving drought resistance in crops.