Photosynthesis research: a model to bridge fundamental science, translational products, and socio-economic considerations in agriculture

Physiological and Transcriptomic Dynamics in Mulberry: Insights into Species-Specific Responses to Midday Depression

Background/Objective: The midday depression of photosynthesis, a physiological phenomenon driven by environmental stress, impacts plant productivity. This study aims to elucidate the molecular and physiological responses underlying midday depression in two mulberry species, Ewu No. 1 (Ew1) and Husan No. 32 (H32), to better understand their species-specific stress adaptation mechanisms. Methods: RNA-seq analysis was conducted on leaf samples collected at three time points (10:00 a.m., 12:00 p.m., and 4:00 p.m.), identifying 22,630 differentially expressed genes (DEGs). A comparative Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis was performed to reveal the involvement of key metabolic and signaling pathways in stress responses. Results: Ew1 displayed enhanced stress tolerance by upregulating genes involved in energy management, water conservation, and photosynthetic processes, maintaining higher photosynthetic rates under midday stress. In contrast, H32 adopted a more conservative response, downregulating genes related to photosynthesis and metabolism, favoring survival at the expense of productivity. The KEGG analysis highlighted starch and sucrose metabolism and plant hormone signaling as critical pathways contributing to these species-specific responses. Conclusions: Ew1's adaptive molecular strategies make it more suitable for environments with variable light and temperature conditions, while H32's conservative approach may limit its productivity. These findings provide valuable insights for breeding programs aimed at improving stress tolerance and photosynthetic efficiency in mulberry and other crops, particularly under fluctuating environmental conditions.

Food system actor perspectives on future-proofing European food systems through plant breeding

Crop improvement is a key innovation area in the pursuit of sustainable food systems. However, realising its potential requires integration of the needs and priorities of all agri-food chain stakeholders. In this study, we provide a multi-stakeholder perspective on the role of crop improvement in future-proofing the European food system. We engaged agri-business, farm- and consumer-level stakeholders, and plant scientists through an online survey and focus groups. Four of each group's top five priorities were shared and related to environmental sustainability goals (water, nitrogen and phosphorus efficiency, and heat stress). Consensus was identified on issues including considering existing alternatives to plant breeding (e.g. management strategies), minimising trade-offs, and addressing geographical variation in needs. We conducted a rapid evidence synthesis on the impacts of priority crop improvement options, highlighting the urgent need for further research examining downstream sustainability impacts to identify concrete targets for plant breeding innovation as a food systems solution.

Endophytic nitrogen-fixing bacteria DX120E inoculation altered the carbon and nitrogen metabolism in sugarcane

Endophytic nitrogen-fixing bacteria are versatile and widely distributed in plants. Numerous strains of endophytic nitrogen-fixing bacteria are used as biofertilizers to minimize the utilization of chemical fertilizers, improve nutrient use efficiency, increase crop productivity, and reduce environmental pollution. However, the mechanism underlying the interaction between nitrogen-fixing bacteria and plants is still unclear. So, the present study was planned to assess the effects of endophytic nitrogen-fixing bacteria on sugarcane by analyzing the changes in physiological and biochemical activities. In the current study, Klebsiella variicola DX120E, an endophytic nitrogen-fixing bacterium, was inoculated on sugarcane varieties B8 and ROC22 to evaluate the effects on nitrogen and carbon metabolism-related enzymatic activity and biomass. Results showed that DX120E inoculation improved the enzymatic activities related to gluconeogenesis and nitrogen metabolism increased the sugarcane plant's height, cane juice Brix, biomass, chlorophyll, and soluble sugar content in sugarcane. Metabolomics analysis revealed that the metabolome modules were highly enriched in carbon and nitrogen metabolic pathways of strain-affected sugarcane than uninoculated control. The identified carbohydrates were associated with the glycolysis or gluconeogenesis and tricarboxylic acid (TCA) cycle in plants. Metabolomic profiling in the present investigation showed that carbohydrate metabolism is coordinated with nitrogen metabolism to provide carbon skeletons and energy to amino acid synthesis, and amino acid degradation results in several metabolites used by the citric acid cycle as an energy source. Moreover, differentially expressed metabolites of non-proteinogenic amino acids have a further complementary role to the action of endophytic nitrogen-fixing bacteria. Meanwhile, a significant difference in metabolites and metabolic pathways present in stems and leaves of B8 and ROC22 varieties was found. This study discovered the potential benefits of DX120E in sugarcane and suggested candidate regulatory elements to enhance interactions between nitrogen-fixing microbes and sugarcane.

Transcriptome-wide modulation by Sargassum vulgare and Acanthophora spicifera extracts results in a prime-triggered plant signalling cascade in tomato and sweet pepper

Seaweed extracts (SWEs) are becoming integrated into crop production systems due to their multiple beneficial effects including growth promotion and induction of defence mechanisms. However, the comprehensive molecular mechanisms of these effects are yet to be elucidated. The current study investigated the transcriptomic changes induced by SWEs derived from Sargassum vulgare and Acanthophora spicifera on tomato and sweet pepper plants. Tomato and sweet pepper plants were subjected to foliar treatment with alkaline extracts prepared from the above seaweeds. Transcriptome changes in the plants were assessed 72 h after treatments using RNA sequencing. The treated plants were also analysed for defence enzyme activities, nutrient composition and phytohormonal profiles. The results showed the significant enrichment of genes associated with several growth and defence processes including photosynthesis, carbon and nitrogen metabolism, plant hormone signal transduction, plant-pathogen interaction, secondary metabolite metabolism, MAPK signalling and amino acid biosynthesis. Activities of defence enzymes were also significantly increased in SWE-treated plants. Plant nutrient profiling showed significant increases in calcium, potassium, nitrogen, sulphur, boron, copper, iron, manganese, zinc and phosphorous levels in SWE-treated plants. Furthermore, the levels of auxins, cytokinins and gibberellins were also significantly increased in the treated plants. The severity of bacterial leaf spot and early blight incidence in plants treated with SWE was significantly reduced, in addition to other effects like an increase in chlorophyll content, plant growth, and fruit yield. The results demonstrated the complex effect of S. vulgare and A. spicifera extracts on the plants' transcriptome and provided evidence of a strong role of these extracts in increasing plant growth responses while priming the plants against pathogenic attack simultaneously. The current study contributes to the understanding of the molecular mechanisms of SWEs in plants and helps their usage as a viable organic input for sustainable crop production.

Leaf photosynthesis: do endophytes have a say?

Endophytes, both bacterial and fungal, constitute an integral component of the leaf ecosystem. Here we argue that the respiratory metabolism of endophytes in the intercellular spaces of leaves could have a significant role in enhancing leaf photosynthesis by enriching the internal CO₂ concentration, especially in C3 plants.

Systems-based rice improvement approaches for sustainable food and nutritional security

An integrated research approach to ensure sustainable rice yield increase of a crop grown by 25% of the world's farmers in 10% of cropland is essential for global food security. Rice, being a global staple crop, feeds about 56% of the world population and sustains 40% of the world's poor. At ~ $200 billion, it also accounts for 13% of the annual crop value. With hunger and malnutrition rampant among the poor, rice research for development is unique in global food and nutrition security. A systems-based, sustainable increase in rice quantity and quality is imperative for environmental and biodiversity benefits. Upstream 'discovery' through biotechnology, midstream 'development' through breeding and agronomy, downstream 'dissemination and deployment' must be 'demand-driven' for 'distinct socio-economic transformational impacts'. Local agro-ecology and livelihood nexus must drive the research agenda for targeted benefits. This necessitates sustained long-term investments by government, non-government and private sectors to secure the future food, nutrition, environment, prosperity and equity status.

Multidimensional analysis model of agricultural product supply chain competition based on mean fuzzy

Efficient and reliable fresh agricultural products supply chain is the key to meet the demand of consumers for fresh agricultural products, and also the guarantee for suppliers to realize their economic benefits. Therefore, a multi-dimensional analysis model of agricultural products supply chain competition based on fuzzy mean value is proposed. Firstly, the information distribution model of multi-dimensional analysis of agricultural product supply chain competition is proposed. On this basis, the multi-dimensional analysis information scheduling fusion of agricultural product supply chain competition is processed. Then, the application of mean value fuzzy in agricultural product supply chain is analyzed. According to the identification module of agricultural product information code, the fuzzy comprehensive evaluation model of supply chain and the mean fuzzy analytic hierarchy process, the competition of agricultural product supply chain is established Dimension analysis model. The experimental results show that the performance score of agricultural product supply chain is higher, the accuracy of supply chain information diagnosis is higher, and the clustering of agricultural product supply chain information diagnosis is better.

Improving crop yield and resilience through optimization of photosynthesis: panacea or pipe dream?

Increasing the speed of breeding to enhance crop productivity and adaptation to abiotic stresses is urgently needed. The perception that a second Green Revolution should be implemented is widely established within the scientific community and among stakeholders. In recent decades, different alternatives have been proposed for increasing crop yield through manipulation of leaf photosynthetic efficiency. However, none of these has delivered practical or relevant outputs. Indeed, the actual increases in photosynthetic rates are not expected to translate into yield increases beyond 10-15%. Furthermore, instantaneous rates of leaf photosynthesis are not necessarily the reference target for research. Yield is the result of canopy photosynthesis, understood as the contribution of laminar and non-laminar organs over time, within which concepts such as canopy architecture, stay-green, or non-laminar photosynthesis need to be taken into account. Moreover, retrospective studies show that photosynthetic improvements have been more common at the canopy level. Nevertheless, it is crucial to place canopy photosynthesis in the context of whole-plant functioning, which includes sink-source balance and transport of photoassimilates, and the availability and uptake of nutrients, such as nitrogen in particular. Overcoming this challenge will only be feasible if a multiscale crop focus combined with a multidisciplinary scientific approach is adopted.

Antioxidants in Plants: A Valorization Potential Emphasizing the Need for the Conservation of Plant Biodiversity in Cuba

Plants are phytochemical hubs containing antioxidants, essential for normal plant functioning and adaptation to environmental cues and delivering beneficial properties for human health. Therefore, knowledge on the antioxidant potential of different plant species and their nutraceutical and pharmaceutical properties is of utmost importance. Exploring this scientific research field provides fundamental clues on (1) plant stress responses and their adaptive evolution to harsh environmental conditions and (2) (new) natural antioxidants with a functional versatility to prevent and treat human pathologies. These natural antioxidants can be valorized via plant-derived foods and products. Cuba contains an enormously rich plant biodiversity harboring a great antioxidant potential. Besides opening new avenues for the implementation of sustainable agroecological practices in crop production, it will also contribute to new strategies to preserve plant biodiversity and simultaneously improve nature management policies in Cuba. This review provides an overview on the beneficial properties of antioxidants for plant protection and human health and is directed to the valorization of these plant antioxidants, emphasizing the need for biodiversity conservation.