Rice Science最新文献

Simultaneous stresses of salinity and drought often coincide during rice-growing seasons in saline lands, primarily due to insufficient water resources and inadequate irrigation facilities. Consequently, combined salinity-drought stress poses a major threat to rice production. In this study, two salinity levels (NS, non-salinity; HS, high salinity) along with three drought treatments (CC, control condition; DJ, drought stress imposed at jointing; DH, drought stress imposed at heading) were performed to investigate their combined influences on leaf photosynthetic characteristics, biomass accumulation, and rice yield formation. Salinity, drought, and their combination led to a shortened growth period from heading to maturity, resulting in a reduced overall growth duration. Grain yield was reduced under both salinity and drought stress, with a more substantial reduction under the combined salinity-drought stress. The combined stress imposed at heading caused greater yield losses in rice compared with the stress imposed at jointing. Additionally, the combined salinity-drought stress induced greater decreases in shoot biomass accumulation from heading to maturity, as well as in shoot biomass and nonstructural carbohydrate (NSC) content in the stem at heading and maturity. However, it increased the harvest index and NSC remobilization reserve. Salinity and drought reduced the leaf area index and SPAD value of flag leaves and weakened the leaf photosynthetic characteristics as indicated by lower photosynthetic rates, transpiration rates, and stomatal conductance. These reductions were more pronounced under the combined stress. Salinity, drought, and especially their combination, decreased the activities of ascorbate peroxidase, catalase, and superoxide dismutase, while increasing the contents of malondialdehyde, hydrogen peroxide, and superoxide radical. Our results indicated a more significant yield loss in rice when subjected to combined salinity-drought stress. The individual and combined stresses of salinity and drought diminished antioxidant enzyme activities, inhibited leaf photosynthetic functions, accelerated leaf senescence, and subsequently lowered assimilate accumulation and grain yield.

Rice has a huge impact on socio-economic growth, and ensuring its sustainability and optimal utilization is vital. This review provides an insight into the role of smart farming in enhancing rice productivity. The applications of smart farming in rice production including yield estimation, smart irrigation systems, monitoring disease and growth, and predicting rice quality and classifications are highlighted. The challenges of smart farming in sustainable rice production to enhance the understanding of researchers, policymakers, and stakeholders are discussed. Numerous efforts have been exerted to combat the issues in rice production in order to promote rice sector development. The effective implementation of smart farming in rice production has been facilitated by various technical advancements, particularly the integration of the Internet of Things and artificial intelligence. The future prospects of smart farming in transforming existing rice production practices are also elucidated. Through the utilization of smart farming, the rice industry can attain sustainable and resilient production systems that could mitigate environmental impact and safeguard food security. Thus, the rice industry holds a bright future in transforming current rice production practices into a new outlook in rice smart farming development.

High-quality rice flour is the foundation for the production of various rice-based products. Milling is an essential step in obtaining rice flour, during which significant changes occur in the physicochemical and quality characteristics of the flour. Although rice flour obtained through mainstream wet milling methods exhibits superior quality, low production efficiency and wastewater discharge limit the development of the industry. Dry milling, on the other hand, conserves water resources, but adversely affects flour performance due to excessive heat generation. As an emerging powder-making technique, semi-dry milling offers a promising solution by enhancing flour quality and reducing environmental impact. This is achieved by minimizing soaking time through hot air treatment while reducing mechanical energy consumption to reach saturated water absorption levels. However, continuous production remains a challenge. This comprehensive review summarizes the effects of various milling technologies on rice flour properties and product qualities. It also discusses key control indicators and technical considerations for rice flour processing equipment and processes.

Excessive waste production has led to the concept of a circular bioeconomy to deliver valuable by-products and improve environmental sustainability. The annual worldwide rice production accounts for more than 750 million tons of grain and 150 million tons of husk. Rice husk (RH) contains valuable biomaterials with extensive applications in various fields. The proportions of each component depend primarily on rice genotype, soil chemistry, and climatic conditions. RH and its derivatives, including ash, biochar, hydrochar, and activated carbon have been placed foreground of applications in agriculture and other industries. While the investigation on RH’s compositions, microstructures, and by-products has been done copiously, owing to its unique features, it is still an open-ended area with enormous scope for innovation, research, and technology. Here, we reviewed the latest applications of RH and its derivatives, including fuel and other energy resources, construction materials, pharmacy, medicine, and nanobiotechnology to keep this versatile biomaterial in the spotlight.

The morphological development of rice (Oryza sativa L.) leaves is closely related to plant architecture, physiological activities, and resistance. However, it is unclear whether there is a co-regulatory relationship between the morphological development of leaves and adaptation to drought environment. In this study, a drought-sensitive, roll-enhanced, and narrow-leaf mutant (renl1) was induced from a semi-rolled leaf mutant (srl1) by ethyl methane sulfonate (EMS), which was obtained from Nipponbare (NPB) through EMS. Map-based cloning and functional validation showed that RENL1 encodes a cellulose synthase, allelic to NRL1/OsCLSD4. The RENL1 mutation resulted in reduced vascular bundles, vesicular cells, cellulose, and hemicellulose contents in cell walls, diminishing the water-holding capacity of leaves. In addition, the root system of the renl1 mutant was poorly developed and its ability to scavenge reactive oxygen species (ROS) was decreased, leading to an increase in ROS after drought stress. Meanwhile, genetic results showed that RENL1 and SRL1 synergistically regulated cell wall components. Our results revealed a theoretical basis for further elucidating the molecular regulation mechanism of cellulose on rice drought tolerance, and provided a new genetic resource for enhancing the synergistic regulation network of plant type and stress resistance, thereby realizing simultaneous improvement of multiple traits in rice.

Nostoc flagelliforme is a terrestrial cyanobacterium that can resist many types of stressors, including drought, ultraviolet radiation, and extreme temperatures. In this study, we identified the drought tolerance gene NfcrtO, which encodes a β-carotene ketolase, through screening the transcriptome of N. flagelliforme under water loss stress. Prokaryotic expression of NfcrtO under 0.6 mol/L sorbitol or under 0.3 mol/L NaCl stress significantly increased the growth rate of Escherichia coli. When NfcrtO was heterologously expressed in rice, the seedling height and root length of NfcrtO-overexpressing rice plants were significantly higher than those of the wild type (WT) plants grown on ½ Murashige and Skoog solid medium with 120 mmol/L mannitol at the seedling stage. Transcriptome analysis revealed that NfcrtO was involved in osmotic stress, antioxidant, and other stress-related pathways. Additionally, the survival rate of the NfcrtO-overexpression lines was significantly higher than that of the WT line under both hydroponic stress (24% PEG and 100 mmol/L H₂O₂) and soil drought treatment at the seedling stage. Physiological traits, including the activity levels of superoxide dismutase, peroxidase, catalase, total antioxidant capacity, and the contents of proline, trehalose, and soluble sugar, were significantly improved in the NfcrtO-overexpression lines relative to those in the WT line under 20% PEG treatment. Furthermore, when water was withheld at the booting stage, the grain yield per plant of NfcrtO-overexpression lines was significantly higher than that of the WT line. Yeast two-hybrid analysis identified interactions between NfcrtO and Dna J protein, E3 ubiquitin-protein ligase, and pyrophosphate-energized vacuolar membrane proton pump. Thus, heterologous expression of NfcrtO in rice could significantly improve the tolerance of rice to osmotic stress, potentially facilitating the development of new rice varieties.