Many efforts have been made to enhance rice photosynthesis for higher grain yields, although such knowledge has seldom been integrated into rice breeding programs. In this review, I first address the limitations and challenges of the theory that yield is controlled by photosynthesis, a concept rooted in the fact that carbon forms a significant part of plant mass, with photosynthesis acting as the fundamental pathway for carbon assimilation. Subsequently, the discussion covers photosynthesis indices, their measurement techniques, and the challenges in establishing correlations between photosynthesis indices and yields. The review then delves into recent advancements, including leveraging natural variations, enhancing the electron transport chain, augmenting the efficiency of ribulose bisphosphate carboxylase/oxygenase (Rubisco), increasing CO₂ concentration around Rubisco, initiatives like the C₄ rice project, strategies for photorespiration bypass, and non-leaf photosynthesis contributions. The conclusion emphasizes future research directions such as advocating for the incorporation of photosynthesis within broader organismic processes, unraveling the complex link between photosynthesis and grain yield, developing efficient and direct methods for photosynthesis phenotyping, and assessing photosynthetic performance under actual field conditions.

With global warming, crop plants are challenged by heat stress during reproductive growth, leading to male sterility and yield reduction. The balance between reactive oxygen species (ROS) generation and scavenging is disrupted by stress, resulting in oxidative stress which is harmful to crop growth. However, recent advances have shown that ROS signaling via proteins that sense the redox state is positive for plant performance under stress. ROS signaling is also involved in regulating anther development, such as timely tapetum degeneration. We summarize recent progress in uncovering the mechanism of heat stress effects on ROS homeostasis and discuss the relationship between oxidative stress and metabolic disorder, which is often observed during anther development under heat stress. We propose experimental and breeding strategies to improve field crop tolerance to heat stress.

Photosynthesis represents the most important biological process on earth and generates food and energy for most living organisms. Increasing photosynthetic efficiency in crops is a feasible strategy to enhance grain yield. Canopy photosynthesis, the integral of photosynthesis of all photosynthetic tissues of an entire plant canopy, is intrinsically linked to biomass production and crop yield and is influenced by both photosynthetic efficiency at the tissue level and canopy architecture, which determines the light environment at that tissue. This review summarizes current methodologies for measuring photosynthesis via gas exchange, fluorescence, and reflectance spectrum at the field, canopy, and leaf levels. Gas exchange techniques include eddy covariance, canopy gas exchange chambers, and organ-level gas exchange methods, which can measure CO₂ and H₂O fluxes. Chlorophyll fluorescence methods include solar-induced fluorescence (SIF), laser-induced fluorescence transient (LIFT), pulse amplitude modulated (PAM) fluorescence, and light induced chlorophyll a fluorescence rise (OJIP transient), which can be used to evaluate photosynthetic efficiency and plant stress responses. One of the commonly used reflectance spectrum methods for studying photosynthesis is the hyperspectral reflectance technique, which can estimate photosynthesis-related traits. High-throughput crop photosynthesis phenotyping can be performed with different combinations of these techniques. This review aims to provide a one-stop resource for researchers working in plant physiology, agronomy, and environmental science and working on either crop management or genetic enhancement to address either food security or the response of plants to global climate change.

Crop production stands as a pivotal pillar of global food security, but its sustainability faces complex challenges from plant diseases, which pose a substantial threat to agricultural productivity. Climate change significantly alters the dynamics of plant pathogens, primarily through changes in temperature, humidity, and precipitation patterns, which can enhance the virulence and spread of various plant diseases. Indeed, the increased frequency of extreme weather events, which is a direct consequence of climate change, creates favorable conditions for outbreaks of plant diseases. As global temperatures rise, the geographic range of many plant pathogens is expanding, exposing new regions and species to diseases previously limited to warmer climates. Climate change not only affects the prevalence and severity of plant diseases but also influences the effectiveness of disease management strategies, necessitating adaptive approaches in agricultural practices. This review presents a thorough examination of the relationship between climate change and plant pathogens and carefully provides an analysis of the interplay between climatic shifts and disease dynamics. In addition to insights into the development of effective strategies for countering the adverse impacts of climate change on plant diseases, these insights hold significant promise for bolstering global crop production resilience against mounting environmental challenges.