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Summary: The chilling stress induced by the global climate change harms rice production, especially at seedling and booting stage, which feed half the population of the world. Although there are key quantitative trait locus genes identified in the individual stage, few genes have been reported and functioned at both stages.Utilizing chromosome segment substitution lines (CSSLs) and a combination of map‐based cloning and phenotypes of the mutants and overexpression lines, we identified the major gene Chilling‐tolerance in Geng/japonica rice 3 (COG3) of q chilling‐tolerance at the booting and seedling stage 11 (qCTBS11) conferred chilling tolerance at both seedling and booting stages.COG3 was significantly upregulated in Nipponbare under chilling treatment compared with its expression in 93‐11. The loss‐of‐function mutants cog3 showed a reduced chilling tolerance. On the contrary, overexpression enhanced chilling tolerance. Genome evolution and genetic analysis suggested that COG3 may have undergone strong selection in temperate japonica during domestication. COG3, a putative calmodulin‐binding protein, physically interacted with OsFtsH2 at chloroplast. In cog3‐1, OsFtsH2‐mediated D1 degradation was impaired under chilling treatment compared with wild‐type.Our results suggest that COG3 is necessary for maintaining OsFtsH2 protease activity to regulate chilling tolerance at the booting and seedling stage. [ABSTRACT FROM AUTHOR]

Abstract: To survive under cold temperatures plants must be able to perceive a cold signal and transduce it into downstream components that induce appropriate defense mechanisms. In addition to inducing adaptive defenses, such as the production of osmotic factors to prevent freezing and the reprogramming of transcriptional pathways, cold temperatures induce changes in plant growth and development which can affect the plant life cycle. In this review, we summarize recent progress in characterizing cold‐related genes and the pathways that allow transduction of the cold signal in plants, focusing primarily on studies in Arabidopsis thaliana and rice (Oryza sativa). We summarize cold perception and signal transduction from the plasma membrane to the nucleus, which involves cold sensors, calcium signals, calcium‐binding proteins, mitogen‐activated protein kinase cascades, and the C‐repeat binding factor/dehydration‐responsive element binding pathways, as well as trehalose metabolism. Finally, we describe the balance between plant organogenesis and cold tolerance mechanisms in rice. This review encapsulates the known cold signaling factors in plants and provides perspectives for ongoing cold signaling research. [ABSTRACT FROM AUTHOR]

A new photoresponsive bent‐core nematic (BCN) material, which exhibits flexoelectric domains (FDs) driven by electric field, is reported. Unexpectedly, it is found that the morphologies of FDs can be controlled by irradiation with light fields. This light tunability is ascribed to the photoisomerization effect of the azo moiety within the BCN molecules, where the ratio of trans and cis isomers changes according to the parameters of the light field, resulting in adjustable electric threshold and periodicity of FDs. Based on this principle, a prototype of controllable optical grating is assembeled, whose operation can be manipulated by the wavelength or intensity of light. Due to the easy, instant, and remote operation by light, this optical, contactless tunability has a great advantage over traditional electric control in tunable photonic devices. [ABSTRACT FROM AUTHOR]