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SUMMARY: Skin color is an important trait that determines the cosmetic appearance and quality of fruits. In cucumber, the skin color ranges from white to brown in mature fruits. However, the genetic basis for this important trait remains unclear. We conducted a genome‐wide association study of natural cucumber populations, along with map‐based cloning techniques, on an F2 population resulting from a cross between Pepino (with yellow‐brown fruit skin) and Zaoer‐N (with creamy fruit skin). We identified CsMYB60 as a candidate gene responsible for skin coloration in mature cucumber fruits. In cucumber accessions with white to pale yellow skin color, a premature stop mutation (C to T) was found in the second exon region of CsMYB60, whereas light yellow cucumber accessions exhibited splicing premature termination caused by an intronic mutator‐like element insertion in CsMYB60. Transgenic CsMYB60c cucumber plants displayed a yellow‐brown skin color by promoting accumulation of flavonoids, especially hyperoside, a yellow‐colored flavonol. CsMYB60c encodes a nuclear protein that primarily acts as a transcriptional activator through its C‐terminal activation motif. RNA sequencing and DNA affinity purification sequencing assays revealed that CsMYB60c promotes skin coloration by directly binding to the YYTACCTAMYT motif in the promoter regions of flavonoid biosynthetic genes, including CsF3′H, which encodes flavonoid 3′‐hydroxylase. The findings of our study not only offer insight into the function of CsMYB60 as dominantly controlling fruit coloration, but also highlight that intronic DNA mutations can have a similar phenotypic impact as exonic mutations, which may be valuable in future cucumber breeding programs. Significance Statement: Genome‐wide association study and map‐based cloning revealed that CsMYB60 regulates mature cucumber fruit skin coloring, which is promising for cucumber breeding. Two loss‐of‐function mutations of CsMYB60 provided color variations in the natural cucumber population. [ABSTRACT FROM AUTHOR]

SUMMARY: The formation of adventitious roots (ARs) derived from hypocotyl is the most important morphological adaptation to waterlogging stress in Cucumis sativus (cucumber). Our previous study showed that cucumbers with the gene CsARN6.1, encoding an AAA ATPase domain‐containing protein, were more tolerant to waterlogging through increased AR formation. However, the apparent function of CsARN6.1 remained unknown. Here, we showed that the CsARN6.1 signal was predominantly observed throughout the cambium of hypocotyls, where de novo AR primordia are formed upon waterlogging treatment. The silencing of CsARN6.1 expression by virus‐induced gene silencing and CRISPR/Cas9 technologies adversely affects the formation of ARs under conditions of waterlogging. Waterlogging treatment significantly induced ethylene production, thus upregulating CsEIL3 expression, which encodes a putative transcription factor involved in ethylene signaling. Furthermore, yeast one‐hybrid, electrophoretic mobility assay and transient expression analyses showed that CsEIL3 binds directly to the CsARN6.1 promoter to initiate its expression. CsARN6.1 was found to interact with CsPrx5, a waterlogging‐responsive class‐III peroxidase that enhanced H2O2 production and increased AR formation. These data provide insights into understanding the molecular mechanisms of AAA ATPase domain‐containing protein and uncover a molecular mechanism that links ethylene signaling with the formation of ARs triggered by waterlogging. Significance Statement: The AAA ATPase domain‐containing protein CsARN6.1 is required for waterlogging stress tolerance, where it regulates adventitious root (AR) formation. However, the functional relevance of this gene remained unknown. Our results reveal that in cucumber, a CsEIL3‐CsARN6.1 regulatory module confers AR formation through H2O2 production, mediated by CsPrx5. [ABSTRACT FROM AUTHOR]

A polarization modulated directional backlight autostereoscopic display is proposed and demonstrated. The system consists of the orthogonally polarized backlight, the Fresnel lens array, a light shaping diffuser film, and a liquid crystal display (LCD) with a microphase retardation film. The autostereoscopic image pair carried by the directional light with different polarization directions is simultaneously projected to different spatial directions. The simulation and experimental results show that the directional projection of parallax images is realized for a high‐quality autostereoscopic display with large viewing angle and continuous viewing volume, hence making it suitable for practical applications. [ABSTRACT FROM AUTHOR]

SUMMARY: Occupation of living space is one of the main driving forces of adaptive evolution, especially for aquatic plants whose leaves float on the water surface and thus have limited living space. Euryale ferox, from the angiosperm basal family Nymphaeaceae, develops large, rapidly expanding leaves to compete for space on the water surface. Microscopic observation found that the cell proliferation of leaves is almost completed underwater, while the cell expansion occurs rapidly after they grow above water. To explore the mechanism underlying the specific development of leaves, we performed sequences assembly and analyzed the genome and transcriptome dynamics of E. ferox. Through reconstruction of the three sub‐genomes generated from the paleo‐hexaploidization event in E. ferox, we revealed that one sub‐genome was phylogenetically closer to Victoria cruziana, which also exhibits gigantic floating leaves. Further analysis revealed that while all three sub‐genomes promoted the evolution of the specific leaf development in E. ferox, the genes from the sub‐genome closer to V. cruziana contributed more to this adaptive evolution. Moreover, we found that genes involved in cell proliferation and expansion, photosynthesis, and energy transportation were over‐retained and showed strong expression association with the leaf development stages, such as the expression divergence of SWEET orthologs as energy uploaders and unloaders in the sink and source leaf organs of E. ferox. These findings provide novel insights into the genome evolution through polyploidization, as well as the adaptive evolution regarding the leaf development accomplished through biased gene retention and expression sub‐functionalization of multi‐copy genes in E. ferox. Significance Statement: Through the separation, reconstruction and evolutionary dissection of the three sub‐genomes of Euryale ferox, we reveal that the three sub‐genomes have different origins, with one sub‐genome showing a closer phylogenetic relationship to Victoria cruziana, which shows a similar adult leaf development process as that in E. ferox. Further analysis revealed that while all three sub‐genomes promoted the evolution of the specific leaf development process in E. ferox, the genes from the sub‐genome closer to V. cruziana contributed more to this adaptive evolution. Moreover, we found that genes involved in cell proliferation and expansion, photosynthesis, and energy transportation were over‐retained in multi‐copies and showed strong expression association with the different leaf development stages in E. ferox. [ABSTRACT FROM AUTHOR]

Summary: Fruit neck length (FNL) is an important quality trait in cucumber because it directly affects its market value. However, its genetic basis remains largely unknown. We identified a candidate gene for FNL in cucumber using a next‐generation sequencing‐based bulked segregant analysis in F2 populations, derived from a cross between Jin5‐508 (long necked) and YN (short necked). A quantitative trait locus (QTL) on chromosome 7, Fnl7.1, was identified through a genome‐wide comparison of single nucleotide polymorphisms between long and short FNL F2 pools, and it was confirmed by traditional QTL mapping in multiple environments. Fine genetic mapping, sequences alignment and gene expression analysis revealed that CsFnl7.1 was the most likely candidate Fnl7.1 locus, which encodes a late embryogenesis abundant protein. The increased expression of CsFnl7.1 in long‐necked Jin5‐508 may be attributed to mutations in the promoter region upstream of the gene body. The function of CsFnl7.1 in FNL control was confirmed by its overexpression in transgenic cucumbers. CsFnl7.1 regulates fruit neck development by modulating cell expansion. Probably, this is achieved through the direct protein–protein interactions between CsFnl7.1 and a dynamin‐related protein CsDRP6 and a germin‐like protein CsGLP1. Geographical distribution differences of the FNL phenotype were found among the different cucumber types. The East Asian and Eurasian cucumber accessions were highly enriched with the long‐necked and short‐necked phenotypes, respectively. A further phylogenetic analysis revealed that the Fnl7.1 locus might have originated from India. Thus, these data support that the CsFnl7.1 has an important role in increasing cucumber FNL. [ABSTRACT FROM AUTHOR]

Waterlogging is a severe environmental stress that causes severe crop productivity losses. Cucumber (Cucumis sativus L.) survives waterlogging by producing adventitious roots (ARs) that enhance gas exchange. Little is known about the role of light and sugars in the waterlogging‐induced production of ARs. The role of these factors in AR production was therefore studied in cucumber seedlings grown in the absence or presence of waterlogging and different light conditions. The effect of photosynthesis was studied by removing the shoots of the seedlings and replacing them with exogenous applications of sucrose or stachyose. Shoot removal inhibited AR emergence and elongation. However, the exogenous application of sugars fully restored AR emergence and partially restored root elongation. The exogenous application of a synthetic auxin restored AR emergence but not AR elongation. Transcriptome profiling analysis was used to determine the effects of light on gene expression in the hypocotyls under these conditions. The levels of transcripts encoding proteins involved in auxin transport and signalling were higher in the light and following the exogenous application of sucrose and stachyose. These results show that the waterlogging‐induced emergence of ARs is regulated by the interaction between sugars and auxin, whereas AR elongation depends only on sugars alone. Cucumber (Cucumis sativus L.) survives waterlogging by producing adventitious roots to enhance gas exchange. However, the molecular mechanisms underlying waterlogging‐induced adventitious root formation is less studied. The present results indicate that waterlogging‐induced adventitious root formation is regulated by an interaction of sugars (especially stachyose and sucrose) and auxin signalling. Sugars act as molecular signals that are mediated by auxin transport and response signalling to induce the adventitious root emergence, and as energy resources for adventitious root elongation. [ABSTRACT FROM AUTHOR]

Imaging delivering to correct retina assisted with tracking technique is a common practice for autostereoscopic displays with stereo two‐view data format. Due to various latencies produced in camera buffering, computer processing, data transmission, and illumination refreshing, delayed image delivery will give rise to a substantial degradation of the 3D display experience. This is particularly obvious for directional backlight 3D displays where significant flickering is resulted as a result of the inherent latency. This work systematically analyzes the source of latency by quantitatively measuring the exact latency value in a typical directional backlight autostereoscopic display. Based on accurate measurement, a motion prediction solution is proposed to improve the synchronization between the backlight illumination and viewer's eye location. Motion prediction helps overcome the lag between the center of illumination and viewer's eye, providing a flicker‐free viewing experience for both a stationary and a moving viewer. [ABSTRACT FROM AUTHOR]

In order to solve the problem of the screen resolution degradation with the existing dual‐view technology, an improved solution is proposed and implemented Theoretical simulation and experimental results show that the display device have a wider viewport range and obtain better dual‐view display effect. It is worth mentioning that the resolution of the screen will not drop. The dual‐view display device is structured by LED backlight, light barrier, holographic diffuser and multi‐focus Fresnel lens. [ABSTRACT FROM AUTHOR]

A LCD as backlight is applied to build up a directional backlight auto‐stereoscopic display system. The greyscale images used to control LCD backlight are simulated and created efficiently. A real‐time auto‐stereoscopic display system is set up, providing a great extensibility for the stereomicroscopy. [ABSTRACT FROM AUTHOR]

with the development of virtual reality technology, a new system related to vision would have been proposed, which not only enable myope people to screen their vision independently but also makes it possible to improve people's vision. In addition, it will reduce labor and medical consumables in the visual acuity screening. [ABSTRACT FROM AUTHOR]

Development of adventitious roots (ARs) at the base of the shoot is an important adaptation of plants to waterlogging stress; however, its physiological mechanisms remain unclear. Here, we investigated the regulation of AR formation under waterlogged conditions by hormones and reactive oxygen species (ROS) in Cucumis sativus L., an agriculturally and economically important crop in China. We found that ethylene, auxin, and ROS accumulated in the waterlogged cucumber plants. On the other hand, application of the ethylene receptor inhibitor 1‐methylcyclopropene (1‐MCP), the auxin transport inhibitor 1‐naphthylphthalamic acid (NPA), or the NADPH oxidase inhibitor diphenyleneiodonium (DPI) decreased the number of ARs induced by waterlogging. Auxin enhanced the expression of ethylene biosynthesis genes, which led to ethylene entrapment in waterlogged plants. Both ethylene and auxin induced the generation of ROS. Auxin‐induced AR formation was inhibited by 1‐MCP, although ethylene‐induced AR formation was not inhibited by NPA. Both ethylene‐ and auxin‐induced AR formation were counteracted by DPI. These results indicate that auxin‐induced AR formation is dependent on ethylene, whereas ethylene‐induced AR formation is independent of auxin. They also show that ROS signals mediate both ethylene‐ and auxin‐induced AR formation in cucumber plants. In response to waterlogging, many plants develop adventitious roots (ARs) to enhance gas exchange and nutrient uptake. Auxin, ethylene, and reactive oxygen species (ROS) all take part in this process, but little is known about how they interact. In cucumber, we report that auxin‐induced AR formation is dependent on ethylene, whereas ethylene‐induced AR formation is independent of auxin. Both ethylene and auxin upregulated genes involved in ROS production, which finally lead to AR formation. These results demonstrate the importance of crosstalk among ethylene, auxin, and ROS and show that the crosstalk is generally different in different plants. [ABSTRACT FROM AUTHOR]

Summary: In plants, the formation of hypocotyl‐derived adventitious roots (ARs) is an important morphological acclimation to waterlogging stress; however, its genetic basis remains fragmentary. Here, through combined use of bulked segregant analysis‐based whole‐genome sequencing, SNP haplotyping and fine genetic mapping, we identified a candidate gene for a major‐effect QTL, ARN6.1, that was responsible for waterlogging tolerance due to increased AR formation in the cucumber line Zaoer‐N. Through multiple lines of evidence, we show that CsARN6.1 is the most possible candidate for ARN6.1 which encodes an AAA ATPase. The increased formation of ARs under waterlogging in Zaoer‐N could be attributed to a non‐synonymous SNP in the coiled‐coil domain region of this gene. CsARN6.1 increases the number of ARs via its ATPase activity. Ectopic expression of CsARN6.1 in Arabidopsis resulted in better rooting ability and lateral root development in transgenic plants. Transgenic cucumber expressing the CsARN6.1Asp allele from Zaoer‐N exhibited a significant increase in number of ARs compared with the wild type expressing the allele from Pepino under waterlogging conditions. Taken together, these data support that the AAA ATPase gene CsARN6.1 has an important role in increasing cucumber AR formation and waterlogging tolerance. [ABSTRACT FROM AUTHOR]

Flicker is one of the most prominent issues in directional backlight autostereoscopic displays. This work studies the flicker characterization over the entire screen with a high‐speed camera. The characterization method shows that it works well to adapt with the practical visual experience and it gives a global quantitative description of the flicker. An artificial intelligent scheme with motion prediction is established to reduce the flicker, which is proved to be effective. [ABSTRACT FROM AUTHOR]

Directional backlight autostereoscopic display (DBAD) is capable of separating the imaging source with the illumination source, hence providing a glasses‐free 3D display with viewing freedom, homogeneous illuminance, high resolution and low crosstalk [1]. DBAD forms an autostereoscopic pair by quickly refreshing the LCD and switching two responding light sources for full resolution display, giving rise to an additional temporal crosstalk because of the finite responding speed to retaining the former image during the refreshing process [2]. On the other hand, a polarizer barrier can be applied for autostereoscopy [3]. To realize simultaneous displaying of an autostereoscopic pair instead of quickly refreshing left and right parallax images, we combine the polarization modulation with DBAD, which can project backlight with different polarized directions to different spatial directions. An orthogonal‐polarized directional backlight‐based autostereoscopic display is then proposed and demonstrated with low crosstalk and high uniformity. [ABSTRACT FROM AUTHOR]

with the development of virtual reality technology, a new system related to vision would have been proposed, which not only enable myope people to screen their vision independently but also makes it possible to improve people's vision. In addition, it will reduce labor and medical consumables in the visual acuity screening. [ABSTRACT FROM AUTHOR]

An ultra‐thin directional backlight auto‐stereoscopic display system with double LCD is put forward. The system includes two display screens, among which one is used as backlight module and another as screen. Based on the directional backlight display system, a real‐time 3D display stereomicroscopy system is also presented. [ABSTRACT FROM AUTHOR]