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Cytoplasmic male sterility (CMS) is a crucial means for the utilization of heterosis, which is of great significance for improving the yield and quality of hybrids. Currently, fertility restorationhas been extensively investigated in crops, but fertility restoration of CMS wheat with Aegilops Juvenalis cytoplasm are poorly understood.Here, a backcross population BC1F1derived from a cross between male sterile line Ju706A, its maintainer line 706B, and restorer line LK783, was used to map Rfd1locus by bulked segregant analysis and wheat 660K SNP genotyping.In which Ju706A displayedcomplete male sterility,and its fertility can be restored by LK783 with a pair of dominant genes Rfd1Rfd1. The locus was located to 2.4-Mb region on chromosome 1BS by markersAX-174254104 and AX-111201011.Combined with transcriptomic analysis and quantitative real-time PCR assay,TraesCS1B02G197400LC, the most likely candidate gene for Rfd1, encoded a pectinesterase which was localized in the cell wall, and was highly expressed in fertile anthers.The silencing of Rfd1 resulted in decreased fertility and heterogeneous expression of Rfd1 promoted pollen germination and affected the vegetative growth.It implies that Rfd1 is required for anther or pollen development and male fertility in CMS wheat with Aegilops Juvenalis cytoplasm. Further, a 7 bp deletion in Ju706A was employed to develop specific marker Xnwafu1 for molecular marker-assisted selection of restorers. Thestudy providesa new understanding for exploring the fertility restoration mechanism of CMS.

Whistle classification plays an essential role in studying the habitat and social behaviours of cetaceans. We obtained six categories of sweep whistles of two Tursiops aduncus individual signals using the passive acoustic mornitoring technique over a period of eight months in the Xiamen area. First, we propose a depthwise separable convolutional neural network for whistle classification. The proposed model adopts the depthwise convolution combined with the followed point-by-point convolution instead of the conventional convolution. As a result, it brings a better classification performance in sample sets with relatively independent features between different channels. Meanwhile, it leads to less computational complexity and fewer model parameters. Second, in order to solve the problem of an imbalance in the number of samples under each whistle category, we propose a random series method with five audio augmentation algorithms. The generalization ability of the trained model was improved by using an opening probability for each algorithm and the random selection of each augmentation factor within specific ranges. Finally, we explore the effect of the proposed augmentation method on the performance of our proposed architecture and find that it enhances the accuracy up to 98.53% for the classification of Tursiops aduncus whistles.

Male reproductive development in higher plants experienced a series of complex biological processes, which can be regulated by Gibberellins (GA). The transcriptional factor GAMYB is a crucial component of GA signaling in anther development. However, the mechanism of GAMYB in wheat male reproduction is less understood. Here, we found that the thermo-sensitive genic male sterilitywheat line YanZhan 4110S displayed delayed tapetum programmed cell death and pollen abortive under the hot temperature stress. Combined with RNA-Sequencing data analysis, TaGAMYB associated with fertility conversion was isolated, which was located in the nucleus and highly expressed in fertility anthers. The silencing of TaGAMYB in wheat displayed fertility decline, defects in tapetum, pollen and exine formation, where the abortion characteristics were the same as YanZhan 4110S. In addition, either hot temperature or GA3 treatment in YanZhan 4110S caused the downregulation of TaGAMYB at binucleate stage and trinucleate stage, as well as fertility decrease. Further, the transcription factor TaWRKY2 significantly changed under GA3-treatment and directly interacted with the TaGAMYB promoter by W-box cis-element. Therefore, we suggested that TaGAMYB may be essential for anther development and male fertility, and GA3 activates TaGAMYB by TaWRKY2 to regulate fertility in wheat.

Major fertility restorer locus for Aegilops kotschyi cytoplasm in wheat, Rfk1 , was mapped to chromosome arm 1BS. Most likely candidate gene is TraesCS1B02G197400LC , which is predicted to encode a pectinesterase/pectinesterase inhibitor. Cytoplasmic male sterility (CMS) is widely used for heterosis and hybrid seed production in wheat. Genes related to male fertility restoration in the presence of Aegilops kotschyi cytoplasm have been reported, but the fertility restoration-associated gene loci have not been investigated systematically. In this study, a BC1F1 population derived from a backcross between KTP116A, its maintainer line TP116B, and its restorer line LK783 was employed to map fertility restoration by bulked segregant RNA-Seq (BSR-Seq). A major fertility allele restorer locus for Ae. kotschyi cytoplasm in wheat, Rfk1, was mapped to chromosome arm 1BS, and it was contributed by LK783. Morphological and cytological studies showed that male fertility restoration occurred mainly after the late uninucleate stage. Based on simple sequence repeat and single-nucleotide polymorphism genotyping, the gene locus was located between Xnwafu_6 and Xbarc137 on chromosome arm 1BS. To further isolate the specific region, six Kompetitive allele-specific polymerase chain reaction markers derived from BSR-Seq were developed to delimit Rfk1 within physical intervals of 26.0 Mb. After searching for differentially expressed genes within the candidate interval in the anthers and sequencing analysis, TraesCS1B02G197400LC was identified as a candidate gene for Rfk1 and it was predicted to encode a pectinesterase/pectinesterase inhibitor. Expression analysis also confirmed that it was specifically expressed in the anthers, and its expression level was higher in fertile lines compared with sterile lines. Thus, TraesCS1B02G197400LC was identified as the most likely candidate gene for Rfk1, thereby providing insights into the fertility restoration mechanism for K-type CMS in wheat.

Thermo-sensitive cytoplasmic male sterility is of great significance to heterosis and hybrid seed production in wheat. Consequently, it is worthwhile to research the genes associated with male sterility. Although polygalacturonases (PGs) have been studied to play a crucial role in male reproduction of many plants, their functions in the reproductive development of wheat remain unclear. Here, TaPG (TraesCS7A02G404900) encoding a polygalacturonase was isolated from the anthers of KTM3315A, a wheat thermo-sensitive cytoplasmic male sterile with Aegilops kotschyi cytoplasm. Expression pattern analyses showed that TaPG was strongly expressed in fertile anthers and its protein was localized in the cell wall. Further verification via barley stripe mosaic virus revealed that the silencing of TaPG exhibited abnormal anthers, premature degradation of tapetum, pollen abortion, and defective pollen wall formation, resulting in the declination of fertility. Conclusively, our research suggested that TaPG contributed to the pollen development and male fertility, which will provide a novel insight into the fertility conversion of thermo-sensitive cytoplasmic male sterility in wheat.

Ocean noise in the western Clarion Clipperton Zone, Pacific Ocean was recorded for 5 min every hour during 2017 and 2018, at a depth of 300 m. The monthly and hourly mean spectrum levels in the 20-1000 Hz band were calculated, along with their skewness, kurtosis, percentile distributions, and spectral probability densities. The high noise levels at low frequencies generated from distant shipping and vocalizations of whales were found to range between 70 and 100 dB (100 Hz) and 64-93 dB (100-200 Hz), respectively. The noise levels at high frequencies (200 Hz), which are typically dominated by wind, were found to be low, ranging from 53 to 75 dB. At frequencies above 200 Hz, noise levels in winter were approximately 5 dB higher than those in summer, consistent with the seasonal variations in wind speed. Fin whales, blue whales, and fishes also potentially contributed to variations in the baseline of ambient noise.

Bioinformatic analysis identified the function of genes regulating wheat fertility. Barley stripe mosaic virus-induced gene silencing verified that the genes TaMut11 and TaSF3 are involved in pollen development and related to fertility conversion. Environment-sensitive genic male sterility is of vital importance to hybrid vigor in crop production and breeding. Therefore, it is meaningful to study the function of the genes related to pollen development and male sterility, which is still not fully understand currently. In this study, YanZhan 4110S, a new thermo-sensitive genic male sterility wheat line, and its near-isogenic line YanZhan 4110 were analyzed. Through comparative transcriptome basic bioinformatics and weighted gene co-expression network to further identify some hub genes, the genes TaMut11 and TaSF3 associated with pollen development and male sterility induced by high-temperature were identified in YanZhan 4110S. Further verification through barley stripe mosaic virus-induced gene silencing elucidated that the silencing of TaMut11 and TaSF3 caused pollen abortion, finally resulting in the declination of fertility. These findings provided data on the abortive mechanism in environment-sensitive genic male sterility wheat.

Background: Environment-sensitive genic male sterility is of vital importance to hybrid vigor in crop production and breeding, therefore, it is meaningful to identify and study the function of the genes related to pollen development and male sterility, which still not fully understanding currently. In this study, Yanzhan 4110S, a new thermo-sensitive genic male sterility (TGMS) wheat line, and its near isogenic line Yanzhan 4110 were carried out cytological features observation, bioinformatics analysis to investgate the abortion state and identified the genes involved in pollen development which have fertility regulation function. Barely stripe mosaic virus-induced gene silencing was used to verify the genes function.Results: Cytological analysis showed pollen abortion event of Yanzhan 4110S occur at the later uninucleate stage (Lun) under higher temperature induction (day/night temperatures of 22 °C/20 °C), when the anthers were collected and assessed for transcriptomic profiling through high-throughput sequencing. We then in-depth analyzed the differentially expressed genes (DEGs) by Gene Ontology, Kyoto Encyclopedia of Genes and Genomes, the results showed that the occurrence of Yanzhan 4110S male-sterility most likely related to metabolic pathway, including phenylpropanoid biosynthesis in the biosynthesis of other secondary metabolites, starch and sucrose metabolism in carbohydrate metabolism, carbon fixation in photosynthetic organisms as well as carbon metabolism in energy metabolism. The weighted gene co-expression network analysis in the transcriptome profiles further identified some hub genes, where the key genes involved in those pathways were intersection between the unique DEGs of Yanzhan 4110S in anther and hub genes, totally 228 genes, which were highly related to pollen development including TaMut11 and TaSF3. Moreover, further verification through barely stripe mosaic virus-induced gene silencing elucidated that the silencing of TaMut11 and TaSF3 caused pollen abortion, finally resulting in the declination of fertility. So, the genes TaMut11 and TaSF3 are related to fertility conversion of Yanzhan 4110S.Conclusion: Through comparative transcriptome bioinformatics analysis, the genes TaMut11 and TaSF3 associated with pollen development and male sterility induced by high temperature were identified in Yanzhan 4110S, and verificated by barely stripe mosaic virus-induced gene silencing. These findings provided researching the abortive mechanism in environment-sensitive genic male sterility wheat.

Four polygalacturonase gene family members were highlighted that contribute to elucidate the roles of polygalacturonase during the fertility conversion process in male-sterile wheat. Polygalacturonase (PG) belongs to a large family of hydrolases with important functions in cell separation during plant growth and development via the degradation of pectin. Specific expressed PGs in anthers may be significant for male sterility research and hybrid wheat breeding, but they have not been characterized in wheat (Triticum aestivum L.). In this study, we systematically studied the PG gene family using the latest published wheat reference genomic information. In total, 113 wheat PG genes were identified, which could be classified into six categories A–F according to their structure characteristics and phylogenetic comparisons with Arabidopsis and rice. Polyploidy and segmental duplications in wheat were proved to be mainly responsible for the expansion of the wheat PG gene family. RNA-seq showed that TaPGs have specific temporal and spatial expression characteristics, in which 12 TaPGs with spike-specific expression patterns were detected by qRT-PCR in different fertility anthers of KTM3315A, a thermo-sensitive cytoplasmic male-sterile wheat. Four of them specific upregulated (TaPG09, TaPG95, and TaPG93) or downregulated (TaPG87) at trinucleate stage of fertile anthers, and further aligning with the homologous in Arabidopsis revealed that they may undertake functions such as anther dehiscence, separation of pollen, pollen development, and pollen tube elongation, thereby inducing male fertility conversion in KTM3315A. These findings facilitate function investigations of the wheat PG gene family and provide new insights into the fertility conversion mechanism in male-sterile wheat.

LIM domain proteins were involved in organizing the cytoskeleton, adjusting the metabolism and gene expression, some of them were specific express in pollen. LIM gene family in plants were studied in sunflower, tobacco, foxtail millet, rape, rice and Arabidopsis thaliana, however, it has not been investigated in wheat to date. In the present study, we totally characterized 29 TaLIM genes through genome-wide analysis, which were divided into two categories and five subclasses according to phylogenetic analysis. RNA-Seq analysis indicated the expression patterns of TaLIM genes have specific temporal and spatial characteristics, especially TaLIM2 was highly expressed in fertility anthers. Phenotypic and cytological of BSMV: TaLIM2 showed that it had defects in the later stage of pollen development and germination, which further testified that TaLIM2 was closely related to fertility conversion. These findings will be useful for functional analysis of LIM genes in wheat fertility and contribute to hybrid wheat breeding.

Background: Polygalacturonase (PG) belongs to a large family of hydrolases with important functions in cell separation during plant growth and development via the degradation of pectin. The specific expression of PG genes in anthers may be significant for male sterility research and hybrid wheat breeding, but it has not been characterized in wheat (Triticum aestivum L.). Results: We systematically studied the PG gene family using the latest published wheat reference genomic information. In total, 113 wheat PG genes were identified and renamed as TaPG01–113 based on their chromosomal positions. The PG genes are unequally distributed on 21 chromosomes and classified according to six categories from A–F. Analysis of the gene structures and conserved motifs demonstrated that the Class C and D TaPGs have relatively short gene sequences and a small number of introns. Class E TaPGs are the least conserved and lack conserved domain III. Polyploidy and segmental duplications in wheat were mainly responsible for the expansion of the wheat PG gene family. Predictions of cis-elements indicate that TaPGs have a wide range of functions, including the responses to light, hypothermia, anaerobic conditions, and hormonal stimulation, as well as being involved in meristematic tissue expression. RNA-seq showed that TaPGs have specific temporal and spatial expression characteristics. Twelve spike-specific TaPGs were screened using RNA-seq data and verified by qRT-PCR in the sterile and fertile anthers of thermo-sensitive male-sterile wheat. Four important candidate genes were identified as involved in the male fertility determination process. In fertile anthers, TaPG09 may be involved in the separation of pollen. TaPG87 and TaPG95 could play important roles in anther dehiscence. TaPG93 may be related to pollen development and pollen tube elongation. Conclusions: We analyzed the wheat PG gene family and identified four important TaPGs with differential expression levels in the wheat fertility conversion process. Our findings may facilitate functional investigations of the wheat PG gene family and provide new insights into the fertility conversion mechanism in male-sterile wheat.

Background: Polygalacturonase (PG) belongs to a large family of hydrolases that undertake many important functions in cell separation during plant growth and development by degrading pectin. The specific expression of PG genes in pollen may have great significance for plant male sterile research and hybrid wheat breeding. However, it has not been reported in wheat ( Triticum aestivum L.). Results: Therefore, we systematically studied the PG gene family using the latest published wheat reference genomic information. A total of 113 PGs were identified and renamed as TaPG01 - 113 based on their position on the chromosome. They were unequally distributed on 21 chromosomes and were classified into six categories of A-F. Analysis of gene structures and conserved motifs revealed that the TaPGs of Class C and D had relatively short gene sequences and a small number of introns, and Class E TaPGs were the least conserved and all members did not have III conserved domain. Segmental duplication has been shown to be one of the major drivers of the expansion of the wheat PG gene family. The cis-element predictions indicate that wheat PGs had a wide range of functions, including response to light, hypothermia, anaerobic and hormonal stimulation, and also involved in meristematic tissue expression. In addition, twelve spike-specific expressions of TaPGs were screened using RNA-seq data, and finally three important genes were identified by expression analysis in the sterile and fertile anthers of thermo-sensitive male sterile wheat. TaPG93 was involved in the pollen development and elongation of pollen tubes, and TaPG87 and TaPG95 played important roles in the separation of pollen grains and the cracking of anthers dehiscence. Conclusions: This study, we performed a thorough analysis of the wheat PG gene family and finally obtained three TaPGs that affect wheat fertility. This will lay a solid foundation for the function exploration of wheat PG gene family and provide new enlightenment for the fertility conversion mechanism of male sterile wheat.