作者机构：
[Jiajun Mao; Mingyao Yao; Li Liao; Bingqian Zhou; Dongfang Zhao; Xuepeng Wu; Junjie Wu; Bo Hong; Tao Chang; Hu Chen] College of Agriculture, Hunan Agricultural University, Changsha, 410128, China;[Jiajun Mao; Mingyao Yao; Li Liao; Bingqian Zhou; Dongfang Zhao; Xuepeng Wu; Junjie Wu; Bo Hong; Tao Chang; Hu Chen] Hunan Branch of National Oilseed Crops Improvement Center, Changsha, 410128, China;[Chunyun Guan] College of Agriculture, Hunan Agricultural University, Changsha, 410128, China. Guanmei@hunau.edu.cn;[Chunyun Guan] Hunan Branch of National Oilseed Crops Improvement Center, Changsha, 410128, China. Guanmei@hunau.edu.cn;[Chunyun Guan] Southern Regional Collaborative Innovation Center for Grain and Oil Crops in China, Changsha, 410128, China. Guanmei@hunau.edu.cn
通讯机构：
[Chunyun Guan; Mei Guan] C;College of Agriculture, Hunan Agricultural University, Changsha, China<&wdkj&>Hunan Branch of National Oilseed Crops Improvement Center, Changsha, China<&wdkj&>Southern Regional Collaborative Innovation Center for Grain and Oil Crops in China, Changsha, China<&wdkj&>College of Agriculture, Hunan Agricultural University, Changsha, China<&wdkj&>Hunan Branch of National Oilseed Crops Improvement Center, Changsha, China<&wdkj&>Southern Regional Collaborative Innovation Center for Grain and Oil Crops in China, Changsha, China
摘要：
Rapeseed (Brassica napus L.) is a major oilseed crop in the middle and lower reaches of the Yangtze River in China. However, it is susceptible to waterlogging stress. This study aimed to investigate the physiological characteristics, cellular changes, and gene expression patterns of rapeseed under waterlogging stress, with the goal of providing a foundation for breeding waterlogging-tolerant rapeseed. The results revealed that waterlogging-tolerant rapeseed exhibited higher levels of soluble sugars and antioxidant enzyme activity, particularly in the roots. Conversely, waterlogging-sensitive rapeseed displayed greater changes in malondialdehyde, proline, and hydrogen peroxide levels. Cellular observations showed that after experiencing waterlogging stress, the intercellular space of rapeseed leaf cells expanded, leading to disintegration of mitochondria and chloroplasts. Moreover, the area of the root xylem increased, the number of vessels grew, and there were signs of mitochondrial disintegration and vacuole shrinkage, with more pronounced changes observed in waterlogging-sensitive rapeseed. Furthermore, significant differences were found in the transcription levels of genes related to anaerobic respiration and flavonoid biosynthesis, and different varieties demonstrated varied responses to waterlogging stress. In conclusion, there are differences in the response of different varieties to waterlogging stress at the levels of morphology, physiological characteristics, cell structure, and gene transcription. Waterlogging-tolerant rapeseed responds to waterlogging stress by regulating its antioxidant defense system. This study provides valuable insights for the development of waterlogging-tolerant rapeseed varieties.
摘要：
<jats:p>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 R2, 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 R2, 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 R2, 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.</jats:p>
通讯机构：
[Guan, CY; Guan, M ] H;Hunan Agr Univ, Coll Agr, Changsha 410128, Peoples R China.;Hunan Branch Natl Oilseed Crops Improvement Ctr, Changsha 410128, Peoples R China.;Southern Reg Collaborat Innovat Ctr Grain & Oil Cr, Changsha 410128, Peoples R China.
关键词：
cadmium stress;rapeseed;selenium;yield traits;soil bacterial community
摘要：
<jats:p>Cadmium (Cd) stress greatly limits the growth of rapeseed, and selenium is a micronutrient that is essential for rapeseed growth, but whether and how selenium application alleviates Cd-induced inhibition remains poorly understood. The present study investigated the alleviating effects of exogenous selenium on rapeseed growth under cadmium (Cd) stress based on the aspects of agronomic traits and soil bacterial community structure and diversity. The results show that low-selenium treatment increased the rapeseed yield by 20.92% by increasing the number of pods per plant under Cd stress, but such effects were not prominent when the selenium application rate was high. Meanwhile, selenium application significantly reduced the cadmium content by 4.74–26.89% in different organs of rapeseed. Further analysis suggested that the benefits of selenium in alleviating Cd stress might be induced by changes in soil bacterial community structure and diversity. In addition, in the functional metabolism spectrum of rapeseed microorganisms treated with selenium, there were 5 primary metabolic pathways with significant differences, and there were 32 and 169 pathways for secondary and tertiary metabolic pathways, respectively. Therefore, selenium treatment in rapeseed soil can alter the composition and metabolic function spectrum of soil microbial communities, ultimately affecting plant growth and Cd tolerance.</jats:p>
通讯机构：
[Guan, M ] H;Hunan Branch Natl Oilseed Crops Improvement Ctr, Changsha, Peoples R China.;Hunan Agr Univ, Coll Agr, Changsha, Peoples R China.;Southern Reg Collaborat Innovat Ctr Grain & Oil Cr, Changsha, Peoples R China.
摘要：
<jats:p>Cytoplasmic male sterile system (CMS) is one of the important methods for the utilization of heterosisin <jats:italic>Brassica napus</jats:italic>. The involvement of long non-coding RNAs (lncRNAs) in anther and pollen development in <jats:italic>B</jats:italic>.<jats:italic>napus</jats:italic> has been recognized, but there is little data on the involvement of lncRNAs in pollen abortion in different types of rapeseed CMS. The present study compared the cytological, physiological and biochemical characteristics of <jats:italic>Nsa</jats:italic> CMS (1258A) and <jats:italic>Pol</jats:italic> CMS (P5A) during pollen abortion, and high-throughput sequencing of flower buds of different sizes before and after pollen abortion. The results showed that insufficient energy supply was an important physiological basis for 1258A and P5A pollen abortion, and 1258A had excessive ROS (reactive oxygen species) accumulation in the stage of pollen abortion. Functional analysis showed that Starch and sucrose metabolism and Sulfur metabolism were significantly enriched before and after pollen abortion in 1258A and P5A, and a large number of genes were down-regulated. In 1258A, 227 lncRNAs had <jats:italic>cis</jats:italic>-targeting regulation, and 240 <jats:italic>cis</jats:italic>-target genes of the lncRNAs were identified. In P5A, 116 lncRNAs had <jats:italic>cis</jats:italic>-targeting regulation, and 101 <jats:italic>cis-</jats:italic>target genes of the lncRNAs were identified. There were five lncRNAs <jats:italic>cis-</jats:italic>target genes in 1258A and P5A during pollen abortion, and <jats:italic>LOC106445716</jats:italic> encodes β-D-glucopyranosyl abscisate β-glucosidase and could regulate pollen abortion. Taken together, this study, provides a new perspective for lncRNAs to participate in the regulation of <jats:italic>Nsa</jats:italic> CMS and <jats:italic>Pol</jats:italic> CMS pollen abortion.</jats:p>
通讯机构：
[Chunyun Guan; Mei Guan] A;Authors to whom correspondence should be addressed.<&wdkj&>Southern Regional Collaborative Innovation Center for Grain and Oil Crops in China, Changsha 410128, China<&wdkj&>College of Agriculture, Hunan Agricultural University, Changsha 410128, China<&wdkj&>Hunan Branch of National Oilseed Crops Improvement Center, Changsha 410128, China
摘要：
The overuse of chemical fertilizers has caused various ecological problems in China, necessitating the development of organic alternative fertilizers. There are few studies on the rapidly emerging organic fertilizer rapeseed green manure, despite the importance of understanding its decomposition efficiency and impact on soil. In this study, using plant residue from 14 rapeseed cultivars, we examined the 30-day decomposition changes under conditions A and B (150 and 300 g of plant residue returned, respectively) and detected the effects of their decomposition on soil nitrogen, phosphorus, potassium, and microorganisms. Under condition B, the 30-day cumulative decomposition and nutrient release rates of rapeseed were higher than those under condition A, and the rapeseed decomposition rate exceeded 50% under both conditions, which is similar to results in legume green fertilizers. Moreover, the decomposition of rapeseed green manure significantly increased the soil nutrient content and effectively improved the soil bacterial community structure and diversity relative to the original soil, especially under condition B. Thiobacillus, Azotobacter, and Pseudomonas are bacteria that responded to plant decomposition, and the abundance of the three bacterial genera after plant decomposition was significantly correlated with the plant decomposition traits and soil nutrient content. In conclusion, rapeseed green manure has potential to offset the use of chemical fertilizers, promoting sustainable agricultural development, and this study provides a reference for such green fertilization measures.
作者机构：
[Wei Zhao] College of Agronomy,Hunan Agricultural University,Changsha,410128,China;[Wei Zhao] Key Laboratory of Biology and Genetic Improvement of Oil Crops,Ministry of Agriculture and Rural Affairs,Oil Crops Research Institute of the Chinese Academy of Agricultural Sciences,Wuhan,430062,China;[Lunwen Qian; Mei Guan; Chunyun Guan] 湖南农业大学;[Jun Liu] 中国农业科学院油料作物研究所
通讯机构：
[Wei Zhao; Chunyun Guan] C;College of Agronomy, Hunan Agricultural University, Changsha, 410128, China<&wdkj&>Key Laboratory of Biology and Genetic Improvement of Oil Crops, Ministry of Agriculture and Rural Affairs, Oil Crops Research Institute of the Chinese Academy of Agricultural Sciences, Wuhan, 430062, China<&wdkj&>College of Agronomy, Hunan Agricultural University, Changsha, 410128, China
关键词：
Brassica napus;Fatty acid desaturase;Genome;Evolution;Gene family
摘要：
Fatty acid (FA) desaturases, as the key enzymes in lipid metabolism, are responsible for biosynthesis of the unsaturated fatty FAs, which play important roles in maintaining cell membrane integrity and multiple stress responses. Although attention has been drawn to some plant FA desaturase genes, their global landscape in oil crops is still lacking. Here, we performed systematic characterization and phylogenomic synteny network analyses of the FA desaturase gene family in polyploid oil crop B. napus and other 54 species covering major streptophyte lineages. A total of 1653 FA desaturase genes were identified from these plant genomes. Based on the broad-scale family phylogeny and functional domains, we proposed a unified eight-group classification system for angiosperm FA desaturases, and found that the origin of genes responsible for FA desaturation evolved early and some genes were absent in different species. Phylogenomic analyses revealed deeply conserved syntenic relationships within each of the eight FA desaturase groups. B. napus contains up to 93 FA desaturase genes from the eight groups. Recurrent duplication events in Brassicaceae contributed to the expansion of FA desaturase genes in B. napus, leading to further functional diversification. These FA desaturase genes exhibited spatio-temporal specific expression patterns in different tissues of B. napus, and a set of FA desaturase genes seem to be orchestrated by key transcriptional factors during seed development, such as zf-HD, B3, GATA3, PEI1, NFYA7, YAB1 and YAB2. Altogether, our data have inferred the evolutionary trajectory of this important gene family across distinct plant lineages, providing theoretical basis for future manipulation of FA desaturase genes to improve the seed oil quality of B. napus.
摘要：
<jats:p>Environmental abiotic stresses limit plant growth, development, and reproduction. This study aims to reveal the response of <jats:italic>Brassica napus</jats:italic> to salt stress. Here, transcriptomics, metabolomics, and proteomics analysis were performed on 15 <jats:italic>Brassica napus</jats:italic> leave samples treated with salt at different times. Through functional enrichment analyzing the differentially expressed genes (DEGs), differential metabolites (DMs) and differentially expressed proteins (DEPs), the key factors that dominate <jats:italic>Brassica napus</jats:italic> response to salt stress were identified. The results showed that the two key hormones responding to salt stress were Abscisic acid (ABA) and jasmonic acid (JA). Salt stress for 24h is an important milestone. <jats:italic>Brassica napus</jats:italic> adjusted multiple pathways at 24h to avoid over-response to salt stress and cause energy consumption. The increased expression in <jats:italic>BnPP2C</jats:italic> is tangible evidence. In response to salt stress, JA and ABA work together to reduce the damage caused by salt stress in <jats:italic>Brassica napus</jats:italic>. The increased expression of all BnJAZs after salt stress highlighted the function of JA that cannot be ignored responding to salt stress. In addition, some metabolites, such as N-acetyl-5-hydroxytryptamine, L-Cysteine and L-(+)-Arginine, play a critical role in maintaining the balance of ROS. Proteins like catalase-3, cysteine desulfurase, HSP90 and P450_97A3 were the most critical differential proteins in response to salt stress. These findings of this study provide data support for <jats:italic>Brassica napus</jats:italic> breeding.</jats:p>
摘要：
To scientifically evaluate and utilize high-oleic acid rape germplasm resources and cultivate new varieties suitable for planting in the Hunan Province, 30 local high-oleic acid rape germplasms from Hunan were used as materials. The 12 personality indices of quality, yield, and resistance were comprehensively evaluated by variability, correlation, principal component, and cluster analyses. The results of variability showed that except for oleic acid, the lowest coefficient of variation was oil content, which was 0.06. Correlation analysis showed that oil content was positively correlated with main traits such as yield per plant and oleic acid, which could be used in the early screening of high-oleic rape germplasm. The results of principal component analysis showed that the 12 personality indicators were integrated into four principal components, and the cumulative contribution rate was 62.487%. The value of comprehensive coefficient 'F' was positively correlated with the first, second, and fourth principal components and negatively correlated with the third principal component. Cluster analysis showed that 30 high-oleic rape germplasms could be divided into four categories consisting of 9 (30%), 6 (20%), 7 (23%), and 8 (27%) high-oleic rape germplasms, each with the characteristics of "high disease resistance", "high yield", "high protein", and "more stability". This study not only provides a reference basis for high-oleic rape breeding but also provides a theoretical basis for their early screening.
摘要：
Oil-body-membrane proteins (OBMPs) are essential structural molecules of oil bodies and also versatile metabolic enzymes involved in multiple cellular processes such as lipid metabolism, hormone signaling and stress responses. However, the global landscape for OBMP genes in oil crops is still lacking. Here, we performed genome-wide identification and characterization of OBMP genes in polyploid crop Brassica napus. B. napus contains up to 88 BnaOBMP genes including 53 oleosins, 20 caleosins and 15 steroleosins. Both whole-genome and tandem duplications have contributed to the expansion of the BnaOBMP gene family. These BnaOBMP genes have extensive sequence polymorphisms, and some harbor strong selection signatures. Various cis-acting regulatory elements involved in plant growth, phytohormones and abiotic and biotic stress responses are detected in their promoters. BnaOBMPs exhibit differential expression at various developmental stages from diverse tissues. Importantly, some BnaOBMP genes display spatiotemporal patterns of seed-specific expression, which could be orchestrated by transcriptional factors such as EEL, GATA3, HAT2, SMZ, DOF5.6 and APL. Altogether, our data lay the foundations for studying the regulatory mechanism of the seed oil storage process and provide candidate genes and alleles for the genetic improvement and breeding of rapeseed with high seed oil content.
摘要：
为了实现单株油菜叶面积“无损、高精确度和高效率”的测量目标, 提出了一套综合运用图像处理法、叶面积仪法、系数回归法(叶长宽积, 以下缩写为L×W)和纸样称重法四种方法的单叶累加测量策略, 并开展了相应的实证研究。测量精确度分析结果表明, 图像处理法、叶面积仪法、系数回归法(L×W)均可实现油菜叶面积的田间无损精确测量, 其中测量精确度图像处理法最高, 叶面积仪法次之, 系数回归法(L×W)最低, 测量误差分别为2.94%、4.47%、6.01%。图像处理法测量叶面积, 对于因拍摄角度差异造成的测量误差不明显。同一方法不同生育期建立相应校正模型更有利于精确的测量。测量效率分析结果表明, 叶面积仪法测量效率最高, 系数回归法(L×W)次之, 图像处理法最低, 但在人力可接受范畴内。结合不同生育期叶数和叶形特点, 并科学处理“高精确度”和“高效率”之间的关系, 制订了一个测量方案, 叶宽大于12 cm的长柄叶主要通过图像处理法进行测量, 叶宽小于12?cm的短柄叶、无柄叶主要以叶面积仪法测量, 所有叶通过系数回归法(L×W)测量, 用于少数残缺或漏测叶片的补充及对其他方法测量结果作对比分析, 通过纸样称重法校正模型进行校正。该方案可为单株油菜叶面积田间无损测量提供技术支撑。 In order to achieve the measurement goal of “non-destructive, high-efficiency and high accuracy” individual rape leaf area, a set of single-leaf accumulative measurement strategies using four methods including image processing method, leaf area meter method, coefficient regression method which specifies leaf length and width product, hereinafter abbreviated “L×W”, and pattern weighing method are proposed, and carried out corresponding empirical research. The measurement accuracy analysis results showed that the image processing method, leaf area meter method, and coefficient regression method (L×W) can achieve field non-destructive and accurate measurement of rape leaf area. The image processing method has the highest measurement accuracy, followed by the leaf area meter method, the accuracy of coefficient regression method (L×W) is the lowest, and the measurement errors are 2.94%, 4.47%, and 6.01%, respectively. The measurement error caused by the difference of shooting angle is not obvious when the leaf area is measured by image processing. It is more conducive to accurate measurement to establish corresponding calibration models for different growth periods in the same method. The results of measurement efficiency analysis showed that the leaf area meter method had the highest measurement efficiency, followed by the coefficient regression method (L×W), and that of the image processing method was the lowest, whereas it is within the scope of manpower acceptable. Combined with the analysis of the number and shape of leaves in different growth periods, and scientifically dealt with the relationship between “high accuracy” and “high efficiency”, the measurement scheme was formulated that the long-petiole leaves with a width of more than 12 cm were mainly measured by image processing method, while short-petiole leaves with a width of less than 12 cm and sessile leaves were mainly measured by leaf area meter method, and all leaves were measured by the coefficient regression method (L×W), which was used to supplement the few incomplete or missed leaves, and to compare the measurement results of other methods, and the measurement scheme was corrected by the calibration model of the paper weighing method. This scheme can provide technical support for the field non-destructive measurement of individual rape leaf area.
