Brazil, a major global rice producer outside Asia, has two key rice-growing regions: subtropical lowlands, where irrigated rice accounts for 78% of national production (1.2 Mha), and tropical uplands, covering 0.31 Mha of rainfed rice. This review provides a comprehensive analysis of rice-based cropping systems in Brazil, discussing agronomic management, sustainability challenges, and potential improvements. The integration of rice, soybean, and pasture systems has enhanced land-use efficiency, soil health, and productivity. Irrigation practices, soil fertility management, and pest control strategies play a crucial role in maximizing yield. Additionally, climate-smart agriculture and no-till adoption are emerging as key strategies for mitigating environmental impacts and improving resilience. Despite advancements, challenges such as climate variability, weed resistance, and water-use efficiency remain critical. This review highlights the importance of continued research and innovation in sustainable rice-based systems.

According to the geochemical niche hypothesis, different species have unique elemental compositions, but the elemental stoichiometry of cotton ( Gossypium genus) has not been systematically studied. The rich variation and patterns in elemental stoichiometry within cotton can indicate potential directions for breeding. We studied the concentrations of 15 elements (carbon, nitrogen, calcium, potassium, sulfur, phosphorus, magnesium, iron, silicon, manganese, boron, zinc, nickel, copper, and molybdenum) in the leaves of 18 different cotton species grown in a common garden and compared them with global plant averages. Compared with the global plant averages, the cotton had advantages in nitrogen, calcium, potassium, sulfur, phosphorus, boron, nickel, and molybdenum concentrations. Through redundancy analysis, we confirmed that the elemental stoichiometric variation in cotton was mainly influenced by ploidy level, domestication status, and genome type, which indicated that the elemental composition of cotton can be adjusted by changes in these aspects. Magnesium and calcium exhibited strong centrality in the elemental network of cotton, limiting the variation in the concentrations of sulfur, iron, zinc, nickel, and boron. These results enhance our understanding of cotton species and suggest that magnesium should be further enhanced in future breeding.

Drought priming is a promising strategy for enhancing plant tolerance to low temperature stress. However, the underlying stress memory mechanisms linking priming to subsequent stress responses remain understood. Here, we integrated physiological, transcriptomic, and metabolomic analyses to identify key stress memory genes or metabolites associated with priming-induced low temperature tolerance in wheat. Our results demonstrated that drought priming significantly improved cold tolerance by enhancing leaf photosynthesis, mitigating oxidative damage, and promoting osmolyte accumulation. These physiological advantages were tightly linked to transcriptional reprogramming of carbohydrate metabolism, antioxidant defense, and hormone signaling pathways, suggesting that drought priming establishes a long-term molecular and metabolic memory that enhances stress tolerance. During stress memory maintenance, primed plants sustained elevated expression of genes related to reactive oxygen species homeostasis, ethylene and brassinosteroid biosynthesis, and indole-3-acetic acid (IAA) catabolism, along with increased accumulation of abscisic acid glucosyl ester (ABA-GE). Additionally, primed plants exhibited higher expression of genes associated with carbon, nitrogen, and energy metabolism while downregulating secondary metabolite biosynthesis genes, optimizing their metabolic state for future stress adaptation. Upon stress retriggering, primed plants rapidly activated ABA, IAA, and Ca 2+ signaling pathways, upregulated antioxidant enzyme and sugar biosynthetic genes, and accumulated polyunsaturated fatty acids, lipids, and specific secondary metabolites, facilitating a swift and effective response to low temperature stress. These findings provide critical insights into the molecular and metabolic basis of stress memory in wheat, offering valuable genetic and biochemical targets for breeding climate-resilient crops and developing strategies to mitigate the impact of environmental stresses. • Drought priming enhances wheat tolerance to low-temperature stress. • It improves photosynthesis, reduces oxidative damage, and accumulates osmolytes. • Stress memory is mediated by specific genes involved in carbohydrate metabolism and hormonal regulation. • Maintenance mechanisms include ROS and hormone biosynthesis regulation. • Retriggering mechanisms involve ABA signaling and lipid accumulation.