摘要：
Rice blast is a globally devastating fungal disease that affects the production of rice (Oryza sativa), and the screening of excellent biocontrol strains is an important direction for the biological control of the fungus that causes rice blast disease (Magnaporthe oryzae). The objectives were to obtain strains that were highly antagonistic to rice blast, analyze the genetic information of the antagonistic bacterium YN-917, and explore the resources of its antagonistic gene cluster. The antagonistic bacteria were isolated and identified by the plate confrontation method, morphological observation, physiological and biochemical identification, and molecular biology methods. In addition, the strains were subjected to whole-genome sequencing, and their sequences were analyzed. Strain YN-917 was screened from healthy rice plants of the variety Xiangzaoxian 24, which is susceptible to rice blast, and it inhibited M. oryzae by 72.63% +/- 1.30%. Additionally, the strain had different degrees of inhibitory effects on various plant pathogenic fungi and was highly resistant to stress. The morphological observation, analysis of physiological and biochemical features, 16S rRNA homology analysis, and wholegenome sequencing analysis revealed that the strain YN-917 was Bacillus cereus (GenBank No.: PRJNA687285). The total length of its whole genome was 5326162 bp, and its average G + C content was 35.37%. It was composed of one circular chromosome and one endoplasmic plasmid. There were 5483 genes encoded on average. They included 105 tRNA genes, 42 self-replicating RNA (sRNA), 178 tandem repeat sequences, three prophages, and nine genomic islands. The prediction of antagonistic gene cluster demonstrated that the genome sequence of YN-917 had six secondary metabolic gene biosynthetic clusters, including those for bacteriocins, siderophores, non-ribosomal peptide synthetases (NRPs), and terpene. This study provides a theoretical basis to further explore microbial resources and their metabolic gene clusters for agricultural biological control.
关键词：
Machine learning;Internet of Things;Green agricultural environment;Rape hyperspectral analysis modeling
摘要：
In recent years, China's agricultural Internet of Things technology has attracted great attention. Document No. 1 emphasizes that we will make every effort to use Internet of Things technology, big data, mobile Internet, cloud computing technology, etc. to promote the progress of "Internet + " modern agriculture. Government departments have taken the lead in accelerating the development of agricultural and animal husbandry technology, improving the infrastructure construction of the agricultural industry chain and upgrading the management decision-making management system, building a comprehensive logistics information management service platform, ensuring effective production scheduling in the agricultural and animal husbandry sales market, and improving the construction Agriculture and animal husbandry industry chain. WSN-based has many advantages over traditional solutions, such as long-term monitoring, accuracy, scalability, easy deployment, and low cost, making wireless sensors widely used in the environment and agriculture. Therefore, in the agricultural Internet of Things, a variety of sensor connection points can be arranged around the crops to form system software and a comprehensive monitoring website, which can help farmers deal with problems in a timely manner and propose corresponding solutions to this. Form an integrated production model based on the agricultural Internet of Things system that generates intelligent decisions.
摘要：
Chlorophyll is one of the key factors for photosynthesis and plays an important role in plant growth and development. We previously isolated an EMS mutagenized rapeseed chlorophyll-reduced mutant (crm1), which had yellow leaf, reduced chlorophyll content and fewer thylakoid stacks. Here, we found that crm1 showed attenuated utilization efficiency of both light energy and CO(2) but enhanced heat dissipation efficiency and greater tolerance to high-light intensity. BSA-Seq analysis identified a single nucleotide change (C to T) and (G to A) in the third exon of the BnaA01G0094500ZS and BnaC01G0116100ZS, respectively. These two genes encode the magnesium chelatase subunit I 1 (CHLI1) that catalyzes the insertion of magnesium into protoporphyrin IX, a pivotal step in chlorophyll synthesis. The mutation sites resulted in an amino acid substitution P144S and G128E within the AAA+ domain of the CHLI1 protein. Two KASP markers were developed and co-segregated with the yellow leaf phenotype in segregating F(2) population. Loss of BnaA01.CHLI1 and BnaC01.CHLI1 by CRISPR/Cas9 gene editing recapitulated the mutant phenotype. BnaA01.CHLI1 and BnaC01.CHLI1 were located in chloroplast and highly expressed in the leaves. Furthermore, RNA-seq analyses revealed the expression of chlorophyll synthesis-related genes were upregulated in the crm1 mutant. These findings provide a new insight into the regulatory mechanism of chlorophyll synthesis in rapeseed and suggest a novel target for improving the photosynthetic efficiency and tolerance to high-light intensity in crops. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s11032-023-01429-6.
通讯机构：
[Chunyun Guan; Mei Guan] A;Authors to whom correspondence should be addressed.<&wdkj&>College of Agriculture, Hunan Agricultural University, Hunan Branch of National Oilseed Crops Improvement Center, Southern Regional Collaborative Innovation Center for Grain and Oil Crops in China, Changsha 410128, China
关键词：
high-oleic-acid rapeseed;lncRNA–mRNA;lipid metabolism;seed development
摘要：
A high oleic acid content is considered an essential characteristic in the breeding of high-quality rapeseed in China. Long-chain non-coding RNA (lncRNA) molecules play an important role in the plant’s growth and its response to stress. To better understand the role of lncRNAs in regulating plant reproductive development, we analyzed whole-transcriptome and physiological data to characterize the dynamic changes in lncRNA expression during the four representative times of seed development of high- and low-oleic-acid rapeseed in three regions. We identified 21 and 14 lncRNA and mRNA modules, respectively. These modules were divided into three types related to region, development stages, and material. Next, we analyzed the key modules related to the oil content and the oleic acid, linoleic acid, and linolenic acid contents with physiological data and constructed the key functional network analysis on this basis. Genes related to lipid metabolism, such as 3-ketoacyl-CoA synthase 16 (KCS16) and acyl-CoA:diacylglycerol acyltransferase 1 (DGAT1), were present in the co-expression network, suggesting that the effect of these genes on lipid metabolism might be embodied by the expression of these lncRNAs. Our results provide a fresh insight into region-, development-stage-, and material-biased changes in lncRNA expression in the seeds of Brassica napus. Some of these lncRNAs may participate in the regulatory network of lipid accumulation and metabolism, together with regulated genes. These results may help elucidate the regulatory system of lncRNAs in the lipid metabolism of high-oleic-acid rapeseed seeds.
通讯机构：
[Yineng Chen; Guanghui Chen] C;College of Information Science & Engineering, Hunan Women’s University, Changsha, P. R. China<&wdkj&>College of Agronomy, Hunan Agricultural University, Changsha, P. R. China
摘要：
Rice variety identification is important for genetic breeding classification and crop yield estimation. Traditional identification methods are time-consuming and inaccurate. This paper proposes a method for rice variety identification based on the hyperspectral characteristics of leaves. Hyperspectral data of rice leaves were collected using a geophysical spectrometer imaging system. To reduce the redundance among the hyperspectral data and save the identification cost, locality preserving projections (LPP) is first applied to extract low-dimensional representative features from the leaf hyperspectral data. Then, support vector machine (SVM) is combined for conducting the identification of rice varieties. The experimental results show that the identification rate of 10 varieties of early rice was found to be 91.67% and the identification rate of 10 varieties of late rice was 97.33%.
作者机构：
[Guan, Chunyun; Zhang, Yin; Chen, Can; Huang, Huang; Xu, Ying] Hunan Agr Univ, Coll Agron, Changsha 410128, Peoples R China.;[Guan, Chunyun; Zhang, Yin; Chen, Can; Huang, Huang] Hunan Engn Res Ctr Rice Field Ecol Planting & Bree, Changsha 410128, Peoples R China.;[Li, Zhengyou] Fisheries Res Inst Guizhou Prov, Guiyang 550025, Peoples R China.;[Luo, Jun] Congjiang Agr & Rural Bur Guizhou Prov, Congjiang 557400, Peoples R China.;[Ren, Bo] Hunan Agr Univ, Coll Resources & Environm, Changsha 410128, Peoples R China.
通讯机构：
[Huang Huang] C;College of Agronomy, Hunan Agricultural University, Changsha 410128, China<&wdkj&>Hunan Engineering Research Center of Rice Field Ecological Planting and Breeding, Changsha 410128, China<&wdkj&>Author to whom correspondence should be addressed.
关键词：
rice-fish-duck symbiosis system;globally important agricultural heritage system;value;technology;challenge;countermeasure
摘要：
The Chinese rice-fish-duck symbiosis system is one of the globally important agricultural heritage systems, with a history of nearly a thousand years. It embodies the wisdom of the Chinese ancestors and has huge comprehensive value, which has extremely important references for the sustainable development of agriculture. The technological core for the rice-fish-duck symbiosis system lies in the selection of rice, fish, and duck varieties and the coupling of agricultural operation time. In the process of modern agriculture, many varieties with high comprehensive benefits have also been applied to the rice-fish-duck system, and the rice-fish-duck model has been further developed. What is worrying is that the transfer of rural labor, the promotion of modern agricultural technology, the low degree of marketization and industrialization, the weakening of cultural awareness, and the change in climate have posed huge threats and challenges to the traditional Chinese rice-fish-duck system. The protection and development of the system are urgently needed. Therefore, we recommend delimiting active protection areas, establishing scientific research bases, improving relevant systems, developing rural tourism markets, and innovating farming technology, which also provide guidance for protecting and developing other agricultural cultural heritages.
摘要：
Ramie (Boehmeria nivea [L.] Gaud.), a nutritious animal feed, is rich in protein and produces a variety of secondary metabolites that increase its palatability and functional composition. Ethylene (ETH) is an important plant hormone that regulates the growth and development of various crops. In this study, we investigated the impact of ETH sprays on the growth and metabolism of forage ramie. We explored the mechanism of ETH regulation on the growth and secondary metabolites of forage ramie using transcriptomic and metabolomic analyses. Spraying ramie with ETH elevated the contents of flavonoids and chlorogenic acid and decreased the lignin content in the leaves and stems. A total of 1076 differentially expressed genes (DEGs) and 51 differentially expressed metabolites (DEMs) were identified in the leaves, and 344 DEGs and 55 DEMs were identified in the stems. The DEGs that affect phenylpropanoid metabolism, including BGLU41, LCT, PER63, PER42, PER12, PER10, POD, BAHD1, SHT, and At4g26220 were significantly upregulated in the leaves. Ethylene sprays downregulated tyrosine and chlorogenic acid (3-O-caffeoylquinic acid) in the leaves, but lignin biosynthesis HCT genes, including ACT, BAHD1, and SHT, were up- and downregulated. These changes in expression may ultimately reduce lignin biosynthesis. In addition, the upregulation of caffeoyl CoA-O-methyltransferase (CCoAOMT) may have increased the abundance of its flavonoids. Ethylene significantly downregulated metabolites, affecting phenylpropanoid metabolism in the stems. The differential 4CL and HCT metabolites were downregulated, namely, phenylalanine and tyrosine. Additionally, ETH upregulated 2-hydroxycinnamic acid and the cinnamyl hydroxyl derivatives (caffeic acid and p-coumaric acid). Cinnamic acid is a crucial intermediate in the shikimic acid pathway, which serves as a precursor for the biosynthesis of flavonoids and lignin. The ETH-decreased gene expression and metabolite alteration reduced the lignin levels in the stem. Moreover, the HCT downregulation may explain the inhibited lignin biosynthesis to promote flavonoid biosynthesis. In conclusion, external ETH application can effectively reduce lignin contents and increase the secondary metabolites of ramie without affecting its growth and development. These results provide candidate genes for improving ramie and offer theoretical and practical guidance for cultivating ramie for forage.
通讯机构：
[Cui, GX ; Liu, XY ] H;Hunan Agr Univ, Sch Chem & Mat Sci, Changsha 410128, Peoples R China.;Hunan Agr Univ, Coll Agron, Changsha 410128, Peoples R China.
关键词：
Cannabidiol;Electrochemical sensing;Gold nanoparticles;Carbon black
摘要：
Cannabidiol (CBD), a significant secondary metabolite of Cannabis sativa L., has pharmacological effects for the treatment of a variety of health conditions, including nerve protection, epilepsy, anti-inflammatory, anti-anxiety, and cancer, which have garnered increasing interest in recent years. Herein, an electrochemical sensing platform was constructed for ultrasensitive determination of CBD, on the base of a glassy carbon electrode (GCE) chemically modified with carbon black (CB) and gold nanoparticles (AuNPs) (CB/AuNPs/GCE). The morphology, structure and electrochemical performance of prepared CB/AuNPs/GCE were characterized by scanning electron microscope (SEM), transmission electron microscopy (TEM), energy dispersive spectroscopy (EDS), Ultraviolet-visible spectroscopy (UV-vis), X-ray powder diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and electrochemical technologies. The effects of pH, scanning rate, enrichment time, enrichment potential and the speculated mechanism of cannabidiol reaction at modified electrode were studied in detail. Under the optimized conditions, the fabricated sensing platform exhibited a great linear response of 0.42 mu A mu M-1 in the concentration range of 0.25 similar to 50.0 mu M. The prepared CB/AuNPs/GCE showed long-term stability, good repeatability and high practicability in real samples of industrial hemp. The proposed sensor can be further enhanced for portable and rapid detection of plant secondary metabolites, providing a basis for food detection, agricultural development, and drug detection.
通讯机构：
[Christian Dubos] I;IPSiM, University Montpellier, CNRS, INRAE, Institut Agro, Montpellier, France<&wdkj&>Author to whom correspondence should be addressed.
摘要：
Iron (Fe) is an essential micronutrient for plant growth and development. Fe availability affects crops' productivity and the quality of their derived products and thus human nutrition. Fe is poorly available for plant use since it is mostly present in soils in the form of insoluble oxides/hydroxides, especially at neutral to alkaline pH. How plants cope with low-Fe conditions and acquire Fe from soil has been investigated for decades. Pioneering work highlighted that plants have evolved two different strategies to mine Fe from soils, the so-called Strategy I (Fe reduction strategy) and Strategy II (Fe chelation strategy). Strategy I is employed by non-grass species whereas graminaceous plants utilize Strategy II. Recently, it has emerged that these two strategies are not fully exclusive and that the mechanism used by plants for Fe uptake is directly shaped by the characteristics of the soil on which they grow (e.g., pH, oxygen concentration). In this review, recent findings on plant Fe uptake and the regulation of this process will be summarized and their impact on our understanding of plant Fe nutrition will be discussed.
摘要：
High oleic acid oilseed rape is a hot research area in the development of functional oilseed rape. At present, the model of predicting the oleic acid content in rapeseed at the early growth stage based on hyperspectral technology lacks a mechanistic explanation. In this study, based on the data collected at the 5-6 leaf stage of oilseed rape, a one-dimensional linear regression prediction model of the oleic acid content in leaves (x) and the oleic acid content in rapeseed (y) was constructed with the regression equation y = 1.83x + 75.26, and the R-2, RMSE, and RPD of the testing set were 0.96, 0.23%, and 4.86, respectively. Then, a support vector regression prediction model of the spectral standard normal transformed feature parameters and the oleic acid content in leaves was constructed, and the R-2, RMSE, and RPD of the testing set were 0.74, 0.21%, and 2.01, respectively. Finally, the sensitive parameter transfer model for the prediction of "spectral standard normal transform feature-oleic acid content in leaves-oleic acid content in rapeseed" was validated, and the R-2, RMSE, and RPD of the full sample test were 0.71, 0.54%, and 0.54, respectively. The results show that although the accuracy of the prediction model after the introduction of the agronomic parameters was reduced compared with the performance of direct prediction by using spectra, the oleic acid content in oilseed rape leaves, as an important intermediate variable, could better explain the relationship between the reflection spectrum of the leaf and the oleic acid content in rapeseed. This study provides a theoretical basis and technical support for hyperspectral remote sensing technology in the quality prediction of rapeseed.
作者机构：
[Dai, Lin Jian; Dai, LJ; Sun, Cheng Lin; Rang, Zhong Wen] Hunan Agr Univ, Coll Agr, Changsha 410128, Peoples R China.;[Zhang, Hui Lin; Cheng, Zhi Jun] China Tobacco Hunan Ind Co Ltd, Raw Mat Procurement Ctr, Changsha 410000, Peoples R China.;[Zhou, Dong Bo] China Tobacco Hunan Ind Co Ltd, Tech Ctr, Changsha 410000, Peoples R China.;[Xie, You] China Tobacco Corp Guizhou Prov Co, Tongren City Co, Jiangkou Branch, Tongren 554300, Peoples R China.
摘要：
To explore the influence of wind speed on the quality of tobacco in this study, we employed a heat pump-powered intensive curing barn and a three-stage curing process. By evaluating the influence of fan parameters on the quality of tobacco leaves at different curing stages, the optimal wind speed was determined. After adopting the optimized wind speed process, the degradation of macromolecular substances was faster, the accumulation of aroma substances was delayed to 55°C, and the accumulation was more complete. Among them, the contents of reducing sugar and total sugar in flue-cured tobacco leaves were 22.25% and 29.2%, respectively, which were lower than those in the control group. The sugar was converted into more aroma substances, and the total amount of neutral aroma substances was 48.82% higher than that of the control group. The content of related aroma substances increased significantly. The content of petroleum ether extract related to aroma substances increased by 0.93% compared with the control group. The macromolecular substances were degraded more fully than the control group, such as the starch content decreased to 1.56%. The results of metabolomics showed that the contents of aldehydes, heterocyclic compounds, alcohols, ketones and esters increased significantly in different degrees after this process. These results show that the optimization of wind speed parameters can significantly improve the baking quality of tobacco leaves. This study provides a reference for the optimization of the flue-cured tobacco baking process.
作者机构：
[Zhou, Yanbiao; Yang, Yuanzhu] Hunan Hybrid Rice Res Ctr, State Key Lab Hybrid Rice, Changsha 410125, Hunan, Peoples R China.;[Zhao, Xinhui; Tang, Qianying; Zhang, Zhihui; Fu, Jun; Liu, Lan; Zhou, Yanbiao; Yang, Runqiu; Yang, Yuanzhu; Tang, Xiaodan] Yuan Longping High Tech Agr Co Ltd, Key Lab Southern Rice Innovat & Improvement, Minist Agr & Rural Affairs, Changsha 410001, Hunan, Peoples R China.;[Zhou, Yanbiao] South China Agr Univ, Coll Life Sci, Guangzhou 510642, Peoples R China.;[Zhang, Zhihui; Yang, Yuanzhu] Huazhong Agr Univ, Coll Plant Sci & Technol, Wuhan 430070, Hubei, Peoples R China.;[Zhao, Xinhui; Yang, Yuanzhu] Hunan Agr Univ, Coll Agron, Changsha 410128, Hunan, Peoples R China.
通讯机构：
[Yang, Yuanzhu; Zhou, Yanbiao] S;State Key Laboratory of Hybrid Rice, Hunan Hybrid Rice Research Center, Changsha, 410125, Hunan, China.;Key Laboratory of Southern Rice Innovation and Improvement, Ministry of Agriculture and Rural Affairs, Yuan Longping High-Tech Agriculture Co., Ltd., Changsha, 410001, Hunan, China.;College of Life Sciences, South China Agricultural University, Guangzhou, 510642, China.;College of Life Sciences, Hunan Normal University, Changsha, 410081, Hunan, China.
关键词：
STK;Salt stress;Rice;ROS scavenging;ABA
摘要：
BACKGROUND: Soil salinization is a major abiotic environmental stress factor threatening crop production throughout the world. Salt stress drastically affects the growth, development, and grain yield of rice (Oryza sativa L.), and the improvement of rice tolerance to salt stress is a desirable approach for meeting increasing food demand. Receptor-like cytoplasmic kinases (RLCKs) play essential roles in plant growth, development and responses to environmental stresses. However, little is known about their functions in salt stress. Previous reports have demonstrated that overexpression of an RLCK gene SALT TOLERANCE KINASE (STK) enhances salt tolerance in rice, and that STK may regulate the expression of GST (Glutathione S-transferase) genes. RESULTS: The expression of STK was rapidly induced by ABA. STK was highest expressed in the stem at the heading stage. STK was localized at the plasma membrane. Overexpression of STK in rice increased tolerance to salt stress and oxidative stress by increasing ROS scavenging ability and ABA sensitivity. In contrast, CRISPR/Cas9-mediated knockout of STK increased the sensitivity of rice to salt stress and oxidative stress. Transcriptome sequencing analysis suggested that STK increased the expression of GST genes (LOC_Os03g17480, LOC_Os10g38140 and LOC_Os10g38710) under salt stress. Reverse transcription quantitative PCR (RT-qPCR) suggested that four stress-related genes may be regulated by STK including OsABAR1, Os3BGlu6, OSBZ8 and OsSIK1. CONCLUSIONS: These findings suggest that STK plays a positive regulatory role in salt stress tolerance by inducing antioxidant defense and associated with the ABA signaling pathway in rice.
通讯机构：
[Houxiang Kang] S;State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China<&wdkj&>Author to whom correspondence should be addressed.
关键词：
Cell division;CRISPR/Cas9 gene editing;Genetic architecture of rice leaf width;Genome-wide association study;Gibberellin;Rice leaf width;Vein width
摘要：
Rice leaf width (RLW) is a crucial determinant of photosynthetic area. Despite the discovery of several genes controlling RLW, the underlying genetic architecture remains unclear. In order to better understand RLW, this study conducted a genome-wide association study (GWAS) on 351 accessions from the rice diversity population II (RDP-II). The results revealed 12 loci associated with leaf width (LALW). In LALW4, we identified one gene, Narrow Leaf 22 (NAL22), whose polymorphisms and expression levels were associated with RLW variation. Knocking out this gene in Zhonghua11, using CRISPR/Cas9 gene editing technology, resulted in a short and narrow leaf phenotype. However, seed width remained unchanged. Additionally, we discovered that the vein width and expression levels of genes associated with cell division were suppressed in nal22 mutants. Gibberellin (GA) was also found to negatively regulate NAL22 expression and impact RLW. In summary, we dissected the genetic architecture of RLW and identified a gene, NAL22, which provides new loci for further RLW studies and a target gene for leaf shape design in modern rice breeding.
摘要：
Salicylic acid (SA) is an essential plant hormone that plays critical roles in basal defence and amplification of local immune responses and establishes resistance against various pathogens. However, the comprehensive knowledge of the salicylic acid 5-hydroxylase (S5H) in rice-pathogen interaction is still elusive. Here, we reported that three OsS5H homologues displayed salicylic acid 5-hydroxylase activity, converting SA into 2,5-dihydroxybenzoic acid (2,5-DHBA). OsS5H1, OsS5H2, and OsS5H3 were preferentially expressed in rice leaves at heading stage and responded quickly to exogenous SA treatment. We found that bacterial pathogen Xanthomonas oryzae pv. oryzae (Xoo) strongly induced the expression of OsS5H1, OsS5H2, and OsS5H3. Rice plants overexpressing OsS5H1, OsS5H2, and OsS5H3 showed significantly decreased SA contents and increased 2,5-DHBA levels, and were more susceptible to bacterial blight and rice blast. A simple single guide RNA (sgRNA) was designed to create oss5h1oss5h2oss5h3 triple mutants through CRISPR/Cas9-mediated gene mutagenesis. The oss5h1oss5h2oss5h3 exhibited stronger resistance to Xoo than single oss5h mutants. And oss5h1oss5h2oss5h3 plants displayed enhanced rice blast resistance. The conferred pathogen resistance in oss5h1oss5h2oss5h3 was attributed to the significantly upregulation of OsWRKY45 and pathogenesis-related (PR) genes. Besides, flg22-induced reactive oxygen species (ROS) burst was enhanced in oss5h1oss5h2oss5h3. Collectively, our study provides a fast and effective approach to generate rice varieties with broad-spectrum disease resistance through OsS5H gene editing.
摘要：
Graphical Abstract and Lay Summary The SPAD value is directly proportional to the nitrogen nutrition of crops. By analyzing the SPAD value, the growth status of plants can be understood, agricultural production management measures can be adjusted in a timely manner, and crop growth and development can be optimized. In this study, a widely used feature extraction method was introduced in finance and stock markets, namely MF‐DFA, to extract multifractal features of cotton canopy spectra, and introduced vegetation index for feature fusion. A hyperspectral feature fusion SPAD value inversion model and a recognition model with different fertilization rates was proposed, achieving excellent model performance. This provides more reference for crop parameter inversion and recognition research. Abstract Hyperspectral remote sensing technology is becoming increasingly popular in various fields due to its ability to provide detailed information about crop growth and nutritional status. The use of hyperspectral technology to predict SPAD (Soil and Plant Analyzer Development) values during cotton growth and adopt precise fertilization management measures is crucial for achieving high yield and fertilizer efficiency. To detect the nitrogen nutrition in cotton canopy leaves quickly, a non‐destructive nitrogen nutrition retrieval model was proposed based on the spectral fusion features of the cotton canopy. The hyperspectral vegetation index and multifractal features were fused to predict the SPAD value and identify the amount of fertilizer applied at different levels. The random decision forest algorithm was used as the model predictor and classifier. A method was introduced which was widely used in the fields of finance and stocks (MF‐DFA) into the field of agriculture to extract fractal features of cotton spectral reflectance. Comparing the fusion feature with multi‐fractal feature and vegetation index, the results showed that the fusion feature parameters had higher accuracy and better stability than using a single feature or feature combination. The R2 was as high as 0.8363, and the RMSE was 1.8767%. Our intelligent model provides a new idea for detecting nitrogen nutrition in cotton canopy leaves rapidly.
摘要：
Rice has an important position in China as well as in the world. With the wide application of rice hybridization technology, the problem of mixing between individual varieties has become more and more prominent, so the variety identification of rice is important for the agricultural production, the phenotype collection, and the scientific breeding. Traditional identification methods are highly subjective and time-consuming. To address this issue, we propose a novel locality preserved selective projection learning (LPSPL) method for non-destructive rice variety identification based on leaf hyperspectral characteristics. The proposed LPSPL method can select the most discriminative spectral features from the leaf hyperspectral characteristics of rice, which is helpful to distinguish different rice varieties. In the experiments, support vector machine (SVM) is adopted to conduct the rice variety identification based on the selected spectral features. The experimental results show that the proposed method here achieves higher identification rates, 96% for the early rice and 98% for the late rice, respectively, which are superior to some state-of-the-art methods.
通讯机构：
[Houxiang Kang; Houxiang Kang Houxiang Kang Houxiang Kang] S;State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
关键词：
3′-UTR;CRISPR/Cas9 technology;domestication;genome-wide association study;rice blast resistance;susceptibility genes
摘要：
Traditional rice blast resistance breeding largely depends on utilizing typical resistance (R) genes. However, the lack of durable R genes has prompted rice breeders to find new resistance resources. Susceptibility (S) genes are potential new targets for resistance genetic engineering using genome-editing technologies, but identifying them is still challenging. Here, through the integration of genome-wide association study (GWAS) and transcriptional analysis, we identified two genes, RNG1 and RNG3, whose polymorphisms in 3'-untranslated regions (3'-UTR) affected their expression variations. These polymorphisms could serve as molecular markers to identify rice blast-resistant accessions. Editing the 3'-UTRs using CRISPR/Cas9 technology affected the expression levels of two genes, which were positively associated with rice blast susceptibility. Knocking out either RNG1 or RNG3 in rice enhanced the rice blast and bacterial blight resistance, without impacting critical agronomic traits. RNG1 and RNG3 have two major genotypes in diverse rice germplasms. The frequency of the resistance genotype of these two genes significantly increased from landrace rice to modern cultivars. The obvious selective sweep flanking RNG3 suggested it has been artificially selected in modern rice breeding. These results provide new targets for S gene identification and open avenues for developing novel rice blast-resistant materials.
