Leaves are the main places for photosynthesis and organic synthesis of cotton.  Leaf shape has important effects on the photosynthetic efficiency and canopy formation, thereby affecting cotton yield.  Previous studies have shown that LMI1 is the main gene regulating leaf shape. In this study, the LMI1 gene (LATE MERISTEM IDENTITY1) was inserted into the 35S promoter expression vector, and cotton plants overexpressing LMI1(OE) were obtained through genetical transformation.  Statistical analysis of the biological traits of T₁ and T₂ populations showed that compared to wild type (WT), OE plants had significant larger leaves, thicker stems and significantly increased dry weight.  Furthermore, plant sections of the main vein and petiole showed that the number of cell in those tissues of OE plants increased significantly.  In addition, RNA-seq analysis revealed differential expression of genes related to gibberellin synthesis and NAC gene family (genes containing the NAC domain) in OE and WT plants, suggesting that LMI1 is involved in secondary wall formation and cell proliferation, and promotes stem thickening.  Moreover, GO (Gene Ontology) analysis enriched the terms of calcium ion binding, and KEGG (Kyoto Encyclopedia of Genes and Genomes) analysis enriched the terms of fatty acid degradation, phosphatidylinositol signal transduction system, and cAMP signal pathway.  These results suggested that LMI1 OE plants were responsive to gibberellin hormone signals, and altered messenger signal (cAMP, Ca²⁺) which amplified this function, to promote the stronger above ground vegetative growth.  This study found the LMI1 soared the nutrient growth in cotton, which is the basic for higher yield.

Rapeseed (Brassica napus L.) is the second most widely grown premium oilseed crop globally, mainly for its vegetable oil and protein meal.  One of the main goals of breeders is producing high-yield rapeseed cultivars with sustainable production to meet the requirements of the fast-growing population.  Besides the pod number, seeds per silique (SS), and thousand-seed weight (TSW), the ovule number (ON) is a decisive yield determining factor of individual plants and the final seed yield.  In recent years, tremendous efforts have been made to dissect the genetic and molecular basis of these complex traits, but relatively few genes or loci controlling these traits have been reported thus far.  This review highlights the updated information on the hormonal and molecular basis of ON and development in model plants (Arabidopsis thaliana).  It also presents what is known about the hormonal, molecular, and genetic mechanism of ovule development and number, and bridges our understanding between the model plant species (A. thaliana) and cultivated species (B. napus).  This report will open new pathways for primary and applied research in plant biology and benefit rapeseed breeding programs.  This synopsis will stimulate research interest to further understand ovule number determination, its role in yield improvement, and its possible utilization in breeding programs. 

Banana is a significant crop, and three banana leaf diseases, including Sigatoka, Cordana and Pestalotiopsis, have the potential to have a serious impact on banana production. Existing studies are insufficient to provide a reliable method for accurately identifying banana leaf diseases. Therefore, this paper proposes a novel method to identify banana leaf diseases. First, a new algorithm called K-scale VisuShrink algorithm (KVA) is proposed to denoise banana leaf images. The proposed algorithm introduces a new decomposition scale k based on the semi-soft and middle course thresholds, the ideal threshold solution is obtained and substituted with the newly established threshold function to obtain a less noisy banana leaf image. Then, this paper proposes a novel network for image identification called Ghost ResNeSt-Attention RReLU-Swish Net (GR-ARNet) based on Resnet50. In this, the Ghost Module is implemented to improve the network's effectiveness in extracting deep feature information on banana leaf diseases and the identification speed; the ResNeSt Module adjusts the weight of each channel, increasing the ability of banana disease feature extraction and effectively reducing the error rate of similar disease identification; the model's computational speed is increased using the hybrid activation function of RReLU and Swish. Our model achieves an average accuracy of 96.98% and a precision of 89.31% applied to 13021 images, demonstrating that the proposed method can effectively identify banana leaf diseases.

Lilium are highly economically valuable ornamental plants that are susceptible to Fusarium wilt caused by Fusarium oxysporum. Lilium regale Wilson, a wild lily native to China, is highly resistant to F. oxysporum. In this study, a WRKY transcription factor, WRKY11, was isolated from L. regale, and its function during the interaction between L. regale and F. oxysporum was characterized. The resistance to F. oxysporum of LrWRKY11 ectopic expression tobacco increased, moreover, the transcriptome sequencing and UHPLC-MS/MS analysis indicated that the methyl salicylate and methyl jasmonate levels rose in LrWRKY11 transgenic tobacco, meanwhile, the expression of lignin/lignans biosynthesis related genes including a dirigent (DIR) were up-regulated. Moreover, the lignin/lignans contents in LrWRKY11 transgenic tobacco also significantly increased compared with the wild-type tobacco. In addition, the resistance of L. regale scales in which LrWRKY11 expression was silenced by RNAi evidently decreased, and additionally, the expression of lignin/lignans biosynthesis related genes including LrDIR1 was significantly suppressed. Therefore, LrDIR1 and its promoter (PLrDIR1) sequence containing the W-box element were isolated from L. regale. The interaction assay indicated that LrWRKY11 specifically bound to the W-box element in PLrDIR1 and activated LrDIR1 expression. Additionally, β-glucuronidase activity in the transgenic tobacco co-expressing LrWRKY11/PLrDIR1-β-glucuronidase was higher than that in transgenic tobacco expressing PLrDIR1-β-glucuronidase alone. Furthermore, the ectopic expression of LrDIR1 in tobacco enhanced the resistance to F. oxysporum and increased the lignin/lignans accumulation. In brief, this study revealed that LrWRKY11 positively regulated L. regale resistance to F. oxysporum through interaction with salicylic acid/jasmonic acid signaling pathways and modulating LrDIR1 expression to accumulate lignin/lignans.

Seed aging tolerance during storage is generally an important trait for crop production, yet the role of small auxin-up RNA genes in conferring seed aging tolerance is largely unknown in rice.  In this study, one small auxin-up RNA gene, OsSAUR33, was found to be involved in the regulation of seed aging tolerance in rice.  The expression of OsSAUR33 was significantly induced in aged seeds compared with unaged seeds during the seed germination phase.  Accordingly, the disruption of OsSAUR33 significantly reduced seed vigor compared to the wild type (WT) in response to natural storage or artificial aging treatments.  The rice OsSAUR33 gene promotes the vigor of aged seeds by enhancing their reactive oxygen species (ROS) level during seed germination, and the accumulation of ROS was significantly delayed in the aged seeds of Ossaur33 mutants in comparison with WT during seed germination.  Hydrogen peroxide (H₂O₂) treatments promoted the vigor of aged seeds in various rice varieties.  Our results provide timely theoretical and technical insights for the trait improvement of seed aging tolerance in rice.

The commercialization of genetically modified crops has increased food production, improved crop quality, reduced pesticide use, promoted changes in agricultural production methods, and become an important new productivity to deal with insect pests and weeds while reducing cultivated land area.  This article provides a comprehensive examination of the global distribution of genetically modified crops in 2023.  It discusses the internal factors that are driving this, such as the increasing number of genetically modified crops and the increased variety of commodities.  It also provides information support and application direction guidance for the new productivity of global agricultural science and technology.

Recently, increasing natural infection cases and experimental animal challenge studies demonstrated domestic cats are susceptible to multiple subtypes influenza A virus (IAV) infections.  Notably, some subtype IAV strains could circulate in domestic cats after cross-species transmission and even infected humans, posing a threat to public health.  Host factors related to viral polymerase activity could determine host range of IAV and acidic nuclear phosphoprotein 32 (ANP32) is the most important one among them.  However, role of cat-derived ANP32 on viral polymerase activity and host range of IAV is still unknown.  In the present study, a total of 10 feline ANP32 (feANP32) splice variants (including 5 feANP32A, 3 feANP32B, and 2 feANP32E) were obtained from domestic cats by RT-PCR.  Sequence alignment results demonstrated amino acid deletions and/or insertions occurred among feANP32 variants, but all feANP32 proteins were primarily localized to cell nucleus.  Minigenome replication systems for several representative IAV strains were established and the support ability of feANP32 on IAV polymerase activity was estimated.  The results indicated that most feANP32A and feANP32B splice variants were able to support all the tested IAV strains, though the support activity of a single feANP32 protein on polymerase activity varied among different IAV strains.  In addition, the role of feANP32 in supporting H3N2 canine influenza virus was determined by investigating viral replication in vitro.  Collectively, our study systematically investigated the support activity of feANP32 on IAV, providing a clue for further exploring the mechanism of susceptibility of cats to IAV.

Maize (Zea mays L.) is a monoecious grass species with separate male and female inflorescences which form the tassel and ear, respectively.  The mature ear inflorescences usually bear hundreds of grains, thus directly influence maize grain production and yield.  Here, we isolated a recessive maize mutant, tasselseed2016 (ts2016), which exhibits pleiotropic inflorescence defects and a reduction in grain yield.  These defects include loss of determinacy and identity in meristems and floral organs, as well as a lack of the lower floret abortion in maize ear, and the smaller grain size.  Using map-based cloning and allelic test, we identified and confirmed a microRNA gene MIR172e as the target gene controlling these related traits.  Furthermore, our evidence uncovered a new potential miR172e/ETHYLENE RESPONSIVE ELEMENT BINDING197 (EREB197) regulatory module which controls the abortion of lower floret in maize ear. Transcriptome analysis revealed that the mutation of MIR172e represses multiple biological processes, particularly the flower development and hormone-related pathways in maize ear.  Additionally, we found the mutation in the DNA sequence of MIR172e affects in RNA transcription, resulting in elongation blockage at the mutant site.  Our results reveal the function and molecular mechanism of MIR172e in maize inflorescences and grain yield, and this study deepens our knowledge of maize inflorescence development.

The practice of intercropping leguminous and gramineous crops is used for promoting sustainable agriculture, optimizing resource utilization, enhancing biodiversity, and reducing reliance on petroleum products.  However, promoting conventional intercropping strategies in modern agriculture can prove challenging.  The innovative technology of soybean maize strip intercropping (SMSI) has been proposed as a solution.  This system has produced remarkable results in improving domestic soybean and maize production for both food security and sustainable agriculture.  In this article, we provide an overview of SMSI and explain how it differs from traditional intercropping.  We also discuss the core principles that foster higher yields and the prospects for its future development.

Feed efficiency (FE) is a crucial economic trait that significantly impacts profitability in intensive sheep production, and can be evaluated by the residual feed intake (RFI) and feed conversion ratio (FCR). However, the underlying genetic mechanisms that underlie FE-related traits in sheep are not fully understood. Herein, we measured the FE-related traits of 1280 Hu sheep and conducted the phenotype statistics and correlation analysis, the result showcase that there was a large variation for FE-related traits, and RFI was significant positive correlation with average daily feed intake (ADFI) and FCR. Moreover, a genome-wide association study (GWAS) was conducted using whole-genome resequencing data to investigate the genetic associations of ADFI, FCR and RFI. For ADFI and FCR traits, two and one single nucleotide polymorphisms (SNPs) exceeded the genome-wide significance threshold, whereas ten and five SNPs exceeded the suggestive significance threshold. For RFI traits, only four SNPs exceeded the suggestive significance threshold. Finally, a total of eight genes (LOC101121953, LOC101110202, CTNNA3, IZUMO3, PPM1E, YIPF7, ZSCAN12 and LOC105603808) were identified as potential candidate genes for FE-related traits. Simultaneously, we further analyzed the effects of two candidate SNPs associated with RFI on growth and FE traits in enlarged experimental population, the results demonstrated that these two SNPs was not significantly associated with growth traits (P > 0.05), but significantly related to RFI traits (P < 0.05). These findings will provide valuable reference data and key genetic variants that can be used to effectively select feed-efficient individual in sheep breeding programs.

Crop improvement is crucial for addressing the global challenges of food security and sustainable agriculture.  Recent advancements in high-throughput phenotyping technologies and artificial intelligence (AI) have revolutionized the field, enabling rapid and accurate assessment of crop traits on a large scale.  The integration of AI and machine learning algorithms with high-throughput phenotyping data has unlocked new opportunities for crop improvement.  AI algorithms can analyze and interpret large datasets, extracting meaningful patterns and correlations between phenotypic traits and genetic factors.  These technologies have the potential to revolutionize plant breeding programs by providing breeders with efficient and accurate tools for trait selection, reducing the time and cost required for variety development.  However, further research and collaborations are needed to overcome the challenges and fully unlock the power of high-throughput phenotyping and AI in crop improvement.  By leveraging AI algorithms, researchers can efficiently analyze phenotypic data, uncover complex patterns, and establish predictive models that enable precise trait selection and crop breeding.  The aim of this review is to explore the transformative potential of integrating high-throughput phenotyping and AI in crop improvement.  The review will encompass an in-depth analysis of recent advancements and applications, highlighting the numerous benefits and challenges associated with high-throughput phenotyping and intelligence.

Bacteria play critical roles in regulating soil phosphorus (P) cycling.  The effects of interactions between crops and soil P-availability on bacterial communities and the feedback regulation of soil P cycling by the bacterial community modifications are poorly understood.  Here, six soybean (Glycinemax) genotypes with differences in P efficiency were cultivated in acidic soils with long-term sufficient or deficient P-fertilizer treatments.  The acid phosphatase (AcP) activities, organic-P concentrations and associated bacterial community compositions were determined in bulk and rhizosphere soils.  The results showed that both soybean plant P content and the soil AcP activity were negatively correlated with soil organic-P concentration in P-deficient acidic soils.  Soil P-availability affected the ɑ-diversity of bacteria in both bulk and rhizosphere soils.  However, soybean had a stronger effect on the bacterial community composition, as reflected by the similar biomarker bacteria in the rhizosphere soils in both P-treatments.  The relative abundance of biomarker bacteria Proteobacteria was strongly correlated with soil organic-P concentration and AcP activity in low-P treatments.  Further high-throughput sequencing of the phoC gene revealed an obvious shift in Proteobacteria groups between bulk soils and rhizosphere soils, which was emphasized by the higher relative abundances of Cupriavidus and Klebsiella, and lower relative abundance of Xanthomonas in rhizosphere soils.  Among them, Cupriavidus was the dominant phoC bacterial genus, and it was negatively correlated with the soil organic-P concentration.  These findings suggest that soybean growth relies on organic-P mineralization in P-deficient acidic soils, which might be partially achieved by recruiting specific phoC-harboring bacteria, such as Cupriavidus.

Identifying the factors that influence farmers' adoption of low-carbon technologies (FA) and understanding their impacts are essential for shaping effective agricultural policies aimed at emission reduction and carbon sequestration in China. Utilizing a meta-analysis of 122 empirical studies, this research delves into 23 driving factors affecting FA and tries to address the inconsistencies found in existing literature. This study systematically examines the effect size, source of heterogeneity, and time-accumulation effect of the driving factors on FA. Key findings are as follows: (1) There is a significant level of heterogeneity in the factors influencing FA, with the exception of farming experience, the sources of heterogeneity come from survey zone, methodology model, technological attributes, report source, financial support, and the sampling year. (2) Age, farming experience, adoption cost exhibit a negative correlation with FA, whereas educational level, health status, technical training, economic and welfare cognition, land contract, soil quality, terrain, information accessibility, demonstration, government promotion, government regulation, government support, agricultural cooperatives member, peer effect, and agricultural income ratio demonstrate a positive correlation. Especially, demonstration and age show a particularly strong correlation. (3) The effect of demonstration, age, economic and welfare cognition, farming experience, land contract, soil quality, information accessibility, government promotion, and support, as well as agricultural cooperative membership and peer effects on FA, are generally stable but exhibit varying degrees of attenuation over time. The effect of village cadre, family income, farm scale, gender, health status, technical training, and off-farm work on FA show notable temporal shifts and maintain a weak correlation with FA. This study plays a pivotal role in shaping China's current low-carbon agriculture policies across various regions. It encourages policymakers to comprehensively consider the stability of key factors, other potential factors, technological attributes, rural economic and social context and their interrelations.

Chinese cabbage is an important leafy vegetable crop with high water demand and susceptibility to drought stress.  To explore the molecular mechanisms underlying the response to drought, we performed a transcriptome analysis of drought-tolerant and -sensitive Chinese cabbage genotypes under drought stress, and uncovered core drought-responsive genes and key signaling pathways.  A co-expression network was constructed by a weighted gene co-expression network analysis (WGCNA) and candidate hub genes involved in drought tolerance were identified.  Furthermore, abscisic acid (ABA) biosynthesis and signaling pathways and their drought responses in Chinese cabbage leaves were systemically explored.  We also found that drought treatment increased the antioxidant enzyme activities and glucosinolate contents significantly.  These results substantially enhance our understanding of the molecular mechanisms underlying drought responses in Chinese cabbage.

Quality and yield are the primary concerns in kiwifruit breeding, but currently, research on the genetic mechanisms of fruit size, shape, and ASA (ascorbic acid) content is very limited, which restricts the development of kiwifruit molecular breeding. In this study, we obtained a total of 8.88 million highly reliable SNP (single nucleotide polymorphism) markers from 140 individuals from the natural hybrid offspring of Actinidia eriantha cv. ‘White’ using whole genome resequencing technology. A genome-wide association study was conducted on eight key agronomic traits, including single fruit weight, fruit shape, ASA content, and number of inflorescences per branch. A total of 59 genetic loci containing potential functional genes were located, and candidate genes related to single fruit weight, fruit length, ASA content, number of inflorescences per branch and other traits were identified within the candidate interval, such as AeWUSCHEL, AeCDK1 (cell cycle dependent kinase), AeAO1 (ascorbic oxidase) and AeCO1 (CONSTANS like 4). By constructing an RNAi vector for AeAO1 and injecting it into the fruit of cv. ‘Midao 31’ to interfere with the expression of the AeAO1 gene, the results showed that the activity of ascorbic oxidase in the fruit of ‘Midao 31’ significantly decreased, while the content of ASA significantly increased. Our study provides valuable insights into the genetic basis of variation in A. eriantha fruit traits, which may benefit molecular marker-assisted breeding efforts.

The sugar beet cyst nematode (Heterodera schachtii) is one of the most destructive pathogens in sugar beet production, which causes serious economic losses every year.  Few molecular details of effectors of H. schachtii parasitism are known.  We analyzed the genome and transcriptome data of H. schachtii and identified multiple potential predicted proteins.  After filtering out predicted proteins with high homology to other plant-parasitic nematodes, we performed functional validation of the remaining effector proteins.  37 putative effectors of H. schachtii were screened based on the Nicotiana benthamiana system for identifying the effectors that inhibit plant immune response, eventually determines 13 candidate effectors could inhibit cell death caused by Bax.  Among the 13 effectors, nine have the ability to inhibit GPA2/RBP1-induced cell death.  All 13 effector-triggered immunity (ETI) suppressor genes were analyzed by qRT-PCR and confirmed to result in a significant downregulation of one or more defense genes during infection compared to empty vector.  For in situ hybridization, 13 effectors were specifically expressed and located in esophageal gland cells.  These data and functional analysis set the stage for further studies on the interaction of H. schachtii with host and H. schachtii parasitic control.

EPSPS is a key gene in the shikimic acid synthesis pathway and has been widely used in breeding crops with herbicide resistance.  However, its role in regulating cell elongation is poorly understood.  Through the overexpression of EPSPS genes, we generated lines resistant to glyphosate that exhibited an unexpected dwarf phenotype.  A representative line, DHR1, exhibits a stable dwarf phenotype throughout its entire growth period.  Except for plant height, the other agronomic traits of DHR1 were similar to its transgenic explants ZM24.  Paraffin section experiments showed that DHR1 internodes were shortened due to reduced elongation and division of internode cells.  Exogenous hormones confirmed that DHR1 is not a classical BR- or GA-related dwarfing mutant.  Hybridization analysis and fine mapping confirmed that the EPSPS gene is the causal gene for dwarfism, and the phenotype can be inherited in different genotypes.  Transcriptome and metabolome analyses showed that genes associated with the phenylpropanoid synthesis pathway were enriched in DHR1 when compared with ZM24.  Flavonoid metabolites were enriched in DHR1, whereas lignin metabolites were decreased.  The enhancement of flavonoids likely resulted in differential expression of auxin signal pathway genes and altered the auxin response, subsequently affecting cell elongation.  This study provides a new strategy for generating dwarfs and will accelerate advancements in light simplification of cultivation and mechanized harvesting for cotton.

Phthalate esters (PAEs) are an emerging pollutant due to widespread distribution in environmental mediums that have attracted widespread attention over recent years.  However, there is little information about tea plantation soil PAEs.  A total of 270 soil samples collected from 45 tea plantations in the major high-quality tea-producing regions of Jiangsu, Zhejiang, and Anhui provinces in China were analyzed for seven PAEs.  The detection frequency of PAEs in tea plantation soil was 100%.  DBP, DEHP, and DiBP were the main congeners in tea plantation soil.  The PAEs concentrations in the upper soil were significantly higher than those in the lower soil.  The concentration of tea plantation soil PAEs in Jiangsu Province was significantly lower than those in Zhejiang and Anhui provinces.  Intercropping with chestnuts can effectively reduce the contamination level of PAEs in tea plantation soil.  Correlation analysis, redundancy analysis, partial correlation analysis, and structural equation modeling methods further confirmed the strong direct influence of factors such as chestnut–tea intercropping, temperature, and agricultural chemicals on the variation of PAEs in tea plantation soil.  The health and ecological risk assessments indicated that non-carcinogenic risk was within a safe range and that there was a high carcinogenic risk via the dietary pathway, with DBP posing the highest ecological risk. 

Blast disease caused by the hemibiotrophic ascomycete fungus, Magnaporthe oryzae is a significant threat to sustainable rice production worldwide. Studies have shown that the blast fungus secretes vast arrays of functionally diverse proteins into the host cell for a successful disease progression. However, the final destinations of these effector proteins inside the host cell and their role in advancing fungal pathogenesis remain a mystery. Here, we reported that a putative mitochondrial targeting non-classically secreted protein (MoMtp) positively regulates conidiogenesis and appressorium maturation in M. oryzae. Moreover, MoMTP gene deletion mutant strains triggered a hypersensitive response when inoculated on rice leaves displaying that MoMtp is essential for the virulence of M. oryzae. In addition, cell wall and oxidative stress results indicated that MoMtp is likely involved in the maintenance of the structural integrity of the fungus cell. Our study also demonstrates an upregulation in the expression pattern of the MoMTP gene at all stages of infection, indicating its possible regulatory role in host invasion and the infectious development of M. oryzae. Furthermore, Agrobacterium infiltration and sheath inoculation confirmed that MoMtp-GFP protein is predominantly localized in the host mitochondria of tobacco leaf and rice cells. Taken together, we conclude that MoMtp protein likely promotes the normal conidiation and pathogenesis of M. oryzae and might have a role in disturbing the proper functioning of the host mitochondria during pathogen invasion.

棉花不仅是重要的天然纺织纤维作物，也是一种重要的食用油来源。棉籽油中约含14%的油酸和59%的亚油酸。提高油酸含量有助于增强棉籽油的氧化稳定性和营养价值。磷脂酰胆碱:二酰基甘油胆碱磷酸转移酶(PDCT)是调控磷脂酰胆碱与二酰基甘油转化的关键酶。本研究克隆了四个棉花PDCT同源基因，分别命名为GhPDCT1-4。发现GhPDCT3和GhPDCT4几乎不表达，而GhPDCT1在棉籽油分积累时期显著上调。利用CRISPR/Cas9系统同时敲除序列高度相似的GhPDCT1和GhPDCT2基因后，ghpdct突变体种子中油酸含量从野生型的14.46%增加到16.49%，而亚油酸含量从59.98%减少到52.83%。此外，ghpdct种子中的棕榈酸和硬脂酸含量也有所增加。本研究获得了油酸含量提高的新型棉籽油种质，有望提升棉花作为油料作物的经济和营养价值，推动棉花产业的升级。

Avian infectious bronchitis (IB) is a highly contagious infectious disease caused by infectious bronchitis virus (IBV), which is prevalent in many countries worldwide and causes serious harm to the poultry industry.  At present, many commercial IBV vaccines have been used for the prevention and control of IB; however, IB outbreaks occur frequently.  In this study, two new strains of IBV, SX/2106 and SX/2204, were isolated from two flocks which were immunized with IBV H120 vaccine in central China.  Phylogenetic and recombination analysis indicated that SX/2106, which was clustered into the GI-19 lineage, may be derived from recombination events of the GI-19 and GI-7 strains and the LDT3-A vaccine.  Genetic analysis showed that SX/2204 belongs to the GVI-1 lineage, which may have originated from the recombination of the GI-13 and GVI-1 strains and the H120 vaccine.  The virus cross-neutralization test showed that the antigenicity of SX/2106 and SX/2204 was different from H120.  Animal experiments found that both SX/2106 and SX/2204 could replicate effectively in the lungs and kidneys of chickens and cause disease and death, and H120 immunization could not provide effective protection against the two IBV isolates.  It is noteworthy that the pathogenicity of SX/2204 has significantly increased compared to the GVI-1 strains isolated previously, with a mortality rate up to 60%.  Considering the continuous mutation and recombination of the IBV genome to produce new variant strains, it is important to continuously monitor epidemic strains and develop new vaccines for the prevention and control of IBV epidemics.

Enhancing photosynthetic efficiency is a major goal for improving crop yields under agricultural field conditions and is associated with chloroplast biosynthesis and development.  In this study, we demonstrate that Golden2-like 1a (BnGLK1a) plays an important role in regulating chloroplast development and photosynthetic efficiency.  Overexpressing BnGLK1a resulted in significant increases in chlorophyll content, the number of thylakoid membrane layers and photosynthetic efficiency in Brassica napus, while knocking down BnGLK1a transcript levels through RNA interference (RNAi) had the opposite effects.  A yeast two-hybrid screen revealed that BnGLK1a interacts with the abscisic acid receptor PYRABACTIN RESISTANCE 1-LIKE 1–2 (BnPYL1–2) and CONSTITUTIVE PHOTOMORPHOGENIC 9 SIGNALOSOME 5A subunit (BnCSN5A), which play essential roles in regulating chloroplast development and photosynthesis.  Consistent with this, BnGLK1a-RNAi lines of B. napus display hypersensitivity to the abscisic acid (ABA) response.  Importantly, overexpression of BnGLK1a resulted in a 10% increase in thousand-seed weight, whereas seeds from BnGLK1a-RNAi lines were 16% lighter than wild type.  We propose that BnGLK1a could be a potential target in breeding for improving rapeseed productivity.  Our results not only provide insights into the mechanisms of BnGLK1a function, but also offer a potential approach for improving the productivity of Brassica species.

The trade-off between yield and environmental effects caused by nitrogen fertilizer application is an important issue in wheat production.  A reduction in fertile florets is one of the main reasons for the lower yields under low nitrogen application rates.  Brassinosteroids (BRs) have been found to play a role in nitrogen-induced rice spikelet degeneration.  However, whether BRs play a role in wheat floret development and the mechanisms involved are not clear.  Therefore, a nitrogen gradient experiment and exogenous spraying experiment were conducted to investigate the role and mechanism of BRs in wheat floret development under low nitrogen stress.  The results showed that as the nitrogen application decreased, the endogenous BRs content of the spikes decreased, photosynthesis weakened, and total carbon, soluble sugar and starch in the spikes decreased, leading to a reduction in the number of fertile florets.  Under low nitrogen stress, exogenous spraying of 24-epibrassinolide promoted photosynthesis, and stimulated stem fructan hydrolysis and the utilization and storage of sucrose in spikes, which directed more carbohydrates to the spikes and increased the number of fertile florets.  In conclusion, BRs mediate the effects of nitrogen fertilizer on wheat floret development, and under low nitrogen stress, foliar spraying of 24-epibrassinolide promotes the flow of carbohydrates from the stem to the spikes, alleviating wheat floret degeneration.

Cotton fiber quality is a persistent concern that determines planting benefits and the quality of finished textile products.  However, the limitations of measurement instruments have hindered the accurate evaluation of some important fiber characteristics (such as fiber maturity, fineness, neps), which in turn has impeded the genetic improvement and industrial utilization of cotton fiber.  Here, twelve single fiber quality traits were measured using Advanced Fiber Information System (AFIS) equipment among 383 accessions of upland cotton (Gossypium hirsutum L.).  Also, eight conventional fiber quality traits were assessed by the High Volume Instrument (HVI) system.  Genome-Wide Association Study (GWAS), linkage disequilibrium (LD) block genotyping and functional identification were conducted sequentially to uncover the associated elite loci and candidate genes of fiber quality traits.  As a result, the pleiotropic locus FL_D11 regulating fiber length related traits was again identified in this study.  More importantly, three novel pleiotropic loci (FM_A03, FF_A05, FN_A07) regulating fiber maturity, fineness and neps respectively were detected on the basis of AFIS traits.  Numerous highly-promising candidate genes were screened out by integrating RNA-seq and qRT-PCR analyses, including the reported GhKRP6 for fiber length and newly identified GhMAP8 for maturity and GhDFR for fineness.  The origin and evolution analysis of pleiotropic loci indicated that the selection pressure on FL_D11, FM_A03 and FF_A05 increased as the breeding period approached and the origins of FM_A03 and FF_A05 were traced back to cotton landraces.  These findings reveal the genetic basis underlying fiber quality and provide insight into genetic improvements and textile utilization of fiber in G. hirsutum.

Marker-assisted selection (MAS) and genomic selection (GS) breeding have greatly improved the efficiency of rice breeding.  Due to the influence of epistasis and gene pleiotropy, how to ensure the actual breeding effect of MAS and GS is still a difficult problem to overcome.  In this study, 113 indica rice varieties (V) and their 565 testcross hybrids (TC) were used as materials to investigate the genetic basis of 12 quality traits and 9 agronomic traits.  The original traits and general combining ability of parents, as well as the original traits and mid-parent heterosis of testcross hybrids were subjected to genome-wide association analysis.  In total, 381 primary significantly associated loci (SAL) and 1759 secondary SALs that had epistatic interaction with these primary SALs were detected. 322 candidate genes located within or nearby the SALs were screened, of which 204 were cloned genes.  A total of 39 MAS molecular modules that are beneficial for trait improvement was identified by pyramiding the superior haplotype of candidate genes and desirable epistatic allele of secondary SALs.  All the SALs were used to construct genetic networks, in which 91 pleiotropic loci were investigated.  Additionally, we estimated the accuracy of genomic prediction in parent varieties and testcross hybrids by incorporating no SALs, primary SALs, secondary SALs or epistatic effect SALs as covariates.  Although the prediction accuracy of the four models was mostly not significantly different in the TC dataset, the incorporation of primary SALs, secondary SALs, and epistatic effect SALs significantly improved the prediction accuracy of 5(26%), 3(16%), and 11(58%) traits in the V dataset, respectively.  These results suggested that SALs and epistatic effect SALs identified based on additive genotype can provide considerable predictive power for parental lines.  These results provide insights into the genetic basis of complex traits and valuable information for molecular breeding in rice.