Search

Extreme events of climate change are increasing, such as droughts and heat waves, causing limitations on growth and yield in relevant food crops, as well as threatening global food security. Brassinosteroids (BRs) are natural or synthetic steroids with significant properties that promote plant growth and development. In the current world scenario, research and solutions that can improve plant tolerance to climate change are strategic to ensure food security. The distinctiveness and novelty of this review lie in its comprehensive and detailed approach to the role of BRs in plants under biotic and abiotic stresses. We consolidate information on the action mechanisms on specific organs, providing detailed experimental conclusions of these plant growth regulators, including also commercial products and concentrations tested aiming to mitigate the adverse effects of the stresses. This practical approach highlights the potential of BRs in agriculture and plant protection against stresses. Additionally, our review presents results with plant models and essential food crops, focusing on multidisciplinary approaches and using physiological, biochemical, nutritional, anatomical and agronomic tools to explain the mechanisms of action of brassinosteroids in plants exposed to abiotic and biotic stresses. [ABSTRACT FROM AUTHOR]

The synchronicity of rain and heat in the summer of China's monsoon region provides sufficient water and heat resources for maize growth. However, the intra-annual distribution of precipitation and the probability of extreme precipitation have been inevitably altered by the ongoing climate change, thus affecting the matching degree between precipitation and crop water requirements (MDPCWR). Evaluating the extent to which the MDPCWR will change in the future is of great importance for food security and the sustainable management of water resources. In this study, considering that different growth stages of crops have different sensitivities to water stress, the AquaCrop model was used to calculate the MDPCWR more accurately. In addition, a cumulative distribution function-transform (CDF-t) method was used to remove the bias of 11 global climate models (GCMs) under two typical emission scenarios (SSP2-4.5 and SSP5-8.5) from phase six of the Coupled Model Intercomparison Project (CMIP6). A comprehensive investigation was conducted on how maize growth, water consumption, and the MDPCWR will respond to future climate change with CO2 concentration enrichment in the Huang–Huai–Hai (3H) region in China by driving a well-tested AquaCrop model with the bias-corrected GCMs outputs. The results indicate the following: (1) The CDF-t method can effectively remove seasonal bias, and it also performs well in eliminating the bias of extreme climate events. (2) Under the SSP2-4.5 scenario, the average maximum temperature will increase by 1.31 °C and 2.44 °C in 2021–2050 and 2051–2080, respectively. The average annual precipitation will increase up to 96.8 mm/year, but it will mainly occur in the form of heavy rain. (3) The increased maize evapotranspiration rate does not compensate for the decreased crop water requirement (up to −32 mm/year), due to a shorter growth cycle. (4) The farmland cultivation layer is not able to hold a significant amount of precipitation, due to the increased frequency of heavy rains, resulting in increased irrigation water requirements for maize over the next two periods, with the maximum value of 12 mm/year. (5) Under different scenarios, the projected future MDPCWR will decrease by 9.3–11.6% due to changes in precipitation patterns and crop water requirements, indicating that it will be more difficult for precipitation to meet the water demand of maize growing in the 3H region. The results can provide comprehensive information to understand the impact of climate change on the agricultural water balance and improve the regional strategy for water resource utilization in the 3H region. [ABSTRACT FROM AUTHOR]

Legume-based livestock forage systems are widespread and socially relevant agroecosystems that are essential for delivering high-quality forage. Therefore, it is critical to determine how climate change and management might affect the functioning of forage agroecosystems. The objective of this study was to explore the potential of sainfoin swards under different management regimes by combining results from an experiment on species diversity effects on yield developed under extreme climatic conditions and a survey of sainfoin (Onobrychis viciifolia Scop.) swards and nutritive value in mountain regions in Catalonia, Western Mediterranean. Our results show that 12–59% of the variability in forage nutritive value parameters was accounted for by management. Young cattle-grazed swards showed higher nutrition quality that decreased faster than sheep-grazed or only mown swards. Mixing sainfoin with orchardgrass increased fiber content (e.g., +22% neutral detergent fiber) and decreased protein (−26%) and lignin (−11%) compared to sainfoin monocultures. However, under the extreme climatic conditions of the last three years, the only diversity effect found on yield was the identity of the species present. We propose that a combination of different sainfoin management regimes might be beneficial regionally for both quality forage production and overall biodiversity conservation, whereas traditional systems may be vulnerable to changing climatic conditions. [ABSTRACT FROM AUTHOR]