Telomere-to-telomere genome assembly of melon(Cucumis melo L.var.inodorus)provides a high-quality reference for meta-QTL analysis of important traits

Melon is an important horticultural crop with extensive diversity in many horticultural groups.To explore its genomic diversity,it is necessary to assemble more high-quality complete genomes from different melon accessions.Meanwhile,a large number of QTLs have been mapped in several studies.Integration of the published QTLs onto a complete genome can provide more accurate information for candidate gene cloning.To address these problems,a telomere-to-telomere(T2T)genome of the elite melon landrace Kuizilikjiz(Cucumis melo L.var.inodorus)was de novo assembled and all the published QTLs were projected onto it in this study.The results showed that a high-quality Kuizilikjiz genome with the size of 379.2 Mb and N50 of 31.7 Mb was de novo assembled using the combination of short reads,PacBio high-fidelity long reads,Hi-C data,and a high-density genetic map.Each chromosome contained the centromere and telomeres at both ends.A large number of structural variations were observed between Kuizilikjiz and the other published genomes.A total of 1294 QTLs published in 67 studies were collected and projected onto the T2T genome.Several clustered,co-localized,and overlapped QTLs were determined.Furthermore,20 stable meta-QTLs were identified,which significantly reduced the mapping intervals of the initial QTLs and greatly facilitated identification of the candidate genes.Collectively,the T2T genome assembly together with the numerous projected QTLs will not only broaden the high-quality genome resources but also provide valuable and abundant QTL information for cloning the genes controlling important traits in melon.

Heterosis of Vine Decline Disease Resistance Caused by the Fungus Monosporascus cannonballus in Melons (Cucumis melo L)

Vine decline disease (VDD) constitutes a menace to melons worldwide. Especially, the one caused by the fungus Monosporascus cannonballus. Thus, resistant plant material must be released to help growers. Hence, our goal was to develop resistant plant material to VDD. More than 600 melon accessions are expected to be tested for disease resistance in M. cannonballus infested soil in Weslaco, Texas, USA, to identify resistance to VDD, and other important traits. So far, at most 7 lines were found to be resistant to VDD and some of them were used to develop elite, muskmelon inbred lines by pedigree breeding following single or double backcrosses. These elite parents were crossed to each other to develop the hybrids M3 and M4. They were also tested in the same infested field in Weslaco. The hybrids were grown using standard commercial practices followed by growers and when their fruits were ready, their roots were sampled as well as scored for disease severity to estimate high and mid-parent heterosis Our results indicate the existence of heterosis regarding resistance to VDD. Thus, resistant plant material can be developed and selection for resistance can be accomplished.

Effect of Algae on Melon(Cucumis melo subsp.agrestis var.conomon)Growth and Development under Drought-Stress Conditions

Due to climate change,it is necessary to develop plant varieties that are resilient to climate conditions and resistant to abiotic and biotic stresses.The use of microalgae,which are microorganisms that contain carbohydrates,proteins,lipids,and vitamins,against drought tolerance is a new approach.The aim of the current study was to determine the drought-related mechanisms in the conomon melon genotype and develop drought-tolerant melon cultivars.Morphological,physiological,pomological,and molecular analyses were carried out on the algae-treated genotypes.It has been determined that commercial algae application provides the best results in leaf temperature,leaf relative water contents(LRWC),plant height,fruit length,fruit diameter,and yield,while Cag Cag(a special river in the region)stream algae application gives better results in main stem diameter.It was determined that the number of nodes in the control(without algae)plots was higher than in the other two treatments.Yield and LRWC and plant height values of genotype 7 were the best values among other genotypes.The leaf temperature measurement was lower on genotype 9 than on the other genotypes.While the highest fruit length value was measured in genotype 1,genotype 8 was superior in the main stem diameter,fruit diameter,and the number of nodes among the remaining plant materials.In terms of yield,it was determined that the interaction between genotype 2 and the commercial algae resulted in the best outcomes.In addition,the results of the genetic evaluation revealed that the materials used were not genetically distant from each other and more detailed genetic evaluations are needed.The molecular kinship analysis revealed that the genotypes used in the study were divided into three distinct groups,with individuals within each group exhibiting a high degree of relatedness to one another.As a result of the study,it was found that the application of microalgae had significant effects on improving the drought tolerance of Cucumis melo subsp.agrestis var.conomon genotypes.

Network Pharmacology and Experimental Study of MomordicineⅠand MomordicineⅡfrom Bitter Melon Saponins in Inhibiting Fat Accumulation

Bitter melon(Momordica Charania L.),a member of the Cucurbitaceae family,is widely distributed across tropical and subtropical regions.Saponin,an important functional component of bitter melon,has been proven to exert hypoglycemic effects similarly to insulin,and also possesses lipid-lowering properties inhibiting preadipocyte differentiation and fat synthesis^([1]).

Co-Treatment of EFF and 1-MCP for Enhancing the Shelf-Life and Aroma Volatile Compounds of Oriental Sweet Melons(Cucumis melo var.makuwa Makino)

Compared to other melon types, oriental sweet melon （Cucumis melo var. makuwa Makino） is quite a different species with a shorter shelf-life due to its typical climacteric behavior and thin pericarp. The purpose of this experiment is to explore the effects of co- treatment of enhanced freshness formulation （EFF） and 1-methylcyclopropene （1-MCP） on physiological changes and the content of aroma volatile compounds introduced by them of two oriental sweet melon cultivars （Yumeiren and Tianbao） during storage. The melons were stored in incubators with temperature of 15~C and a relative humidity of 85% for 24 d during which fruit quality and related physiological index were measured. Compared to the control, both treatments delayed fruit weight loss rate and kept the fruit firmness, water content and soluble solids content. Ascorbate peroxidase （APX） and phenylalanine ammonia lyase （PAL） activities showed fluctuations in treated melons, while lipoxygenase （LOX） activity （P〈0.01） and malondialdehyde （MDA） content （P〈0.05） decreased compared to control. During the early stage of storage, alcohols and aldehydes were the main volatile compounds, and esters gradually increased during storage. Of all the esters, acetic esters were the main components, followed by oxalic acid esters and other esters. The total content of aroma volatile compounds, esters, alcohols and aldehydes of co-treated melons were all higher than those of 1-MCP treated and control melons. In addition, the aroma volatile peak of co-treated melons occurred later than that of 1-MCP treated and control melons. In summary, co-treatment of EFF and 1-MCP was more beneficial than 1-MCP treatment to delay ripening and senescence, maintain fruit quality, enhance shelf-life and improve levels of aroma volatile compounds.

Breeding melon(Cucumis melo)with resistance to powdery mildew and downy mildew

Melon(Cucumis melo L.)production is often restricted by a plethora of pests and diseases,including powdery mildew and downy mildew caused respectively by the fungal species Podosphaera xanthii/Golovinomyces orontii and oomycete species Pseudoperonospora cubensis.Many efforts have been directed on identification of resistant sources by screening(wild)melon germplasm.In the current review,we summarized such efforts from various publications of the last 50 plus years.Resistance to powdery mildew has been identified in 239 melon accessions and downy mildew resistance in 452 accessions of both C.melo and the wild relative species C.figarei.Among the resistance sources,C.melo var.cantalupensis accessions PMR 45,PMR 5,PMR 6,and WMR 29 as well as C.melo var.momordica accessions PI 124111,PI 124112,and PI 414723 have been considered as the most valuable germplasm because multiple resistance genes have been identified from these accessions and are widely used in melon resistance breeding.Further genetic mapping in a number of resistant sources has enabled identification of 25 dominant genes,two recessive genes and seven QTLs conferring powdery mildew resistance,as well as eight dominant genes and 11 QTLs for downy mildew resistances.Based on the reported sequences of associated markers,we anchored physically(many of)these genes and QTLs to chromosomes of the melon cv.DHL92 genome.In addition to presenting a comprehensive overview on powdery mildew and downy mildew resistance in(wild)melon germplasm,we suggest strategies aiming at breeding melon with durable and broad-spectrum resistance to pathogens and pests.

Comparative Analysis of Gene Expression in Two Muskmelon Cultivars(Cucumis melo L.) Under Salt Stress

Salinity is one of the most important abiotic stresses that adversely affects crop growth and productivity. A subtractive suppression hybridization （SSH） library were constructed from the roots of salt-sensitive Yulu cultivar melon seedlings under salt stress; 557 high-quality expressed sequence tags （ESTs） were randomly sequenced, with an average size of 428 bp, which assembled into 68 contigs and 315 singletons. Compared with our previous SSH library generated from the salt-tolerant Bingxuecui cultivar, the proportion of transcripts involved in metabolism, protein fate, cellular communication/signal transduction mechanisms, and cell rescue/defense were 4, 1.46, 0.94, and 0.4% higher, respectively, in the salt-tolerant cultivar than the in salt-sensitive cultivar. Quantitative real-time PCR analysis of eleven transcripts revealed temporal variations in their expression in the two cultivars under salt stress. One NAC gene （JZ477011） was heterologously expressed in yeast for functional characterization, and enhanced the sensitivity of yeast cells to high-salinity to salt stress and inhibited their growth. Information regards to their functions would aid in the understanding of response mechanisms to saline stress and in the development of molecular markers for selecting salt-tolerant melon cultivars.

Genome-Wide GRAS Gene Family Analysis Reveals the Classification,Expression Profiles in Melon(Cucumis melo L.)

Melon(Cucumis melo),belonging to the Cucurbitaceae family,is a globally important economic crop.GRAS(GAI,RGA,SCR)genes,which are a type of transcription factor,play a critical role in plant growth and development,including processes such as radial root patterning,light signalling,abiotic/biotic stress,axillary shoot meristem formation,and phytohormone(gibberellin)signal transduction.In this study,the GRAS family in melon was analysed comprehensively with respect to chromosomal location,motif prediction,gene structure,and expression pattern.A total of 37 GRAS genes were first identified in melon,after which a phylogenetic tree was built with the GRAS genes of three model species(Arabidopsis,rice,and sacred lotus)and were divided into nine groups based on the findings of previous studies.Motif and gene structure analysis showed typical conserved domains in all melon GRAS and similar structures in the same subfamilies.The expression analysis of GRAS genes done using RNA-seq data,showed that these genes were differentially expressed in different melon leaves under powdery mildew stress.Furthermore,the real-time quantitative PCR for GRAS genes revealed gene expression corresponding to powdery mildew stress.Our results provide useful information for a better understanding of GRAS genes and provide the foundation for additional functional exploration of the melon GRAS gene family in the powdery mildew stress response.

Effects of abiotic stress and hormones on the expressions of five13-CmLOXs and enzyme activity in oriental melon(Cucumis melo var.makuwa Makino)

Lipoxygenases（LOXs） are a group of non-heme,iron-containing enzymes and extensively involved in plant growth and development,ripening and senescence,stress responses,biosynthesis of regulatory molecules and defense reaction.In our previous study,18 LOXs in melon genome were screened and identified,and five 13-LOX genes（CmLOX08,CmLOX10,CmLOX12,CmLOX13 and CmLOX18） were predicted to locate in chloroplast.Phylogenetic analysis result showed that the five genes have high homology with jasmonic acid（JA） biosynthesis-related LOXs from other plants.In addition,promoter analysis revealed that motifs of the five genes participate in gene expression regulated by hormones and stresses.Therefore,we analyzed the expressions of the five genes and LOX activity in leaves of four-leaf stage seedlings of oriental melon cultivar Yumeiren under abiotic stress：wounding,cold,high temperature and hydrogen peroxide（H_2O_2）,and signal molecule treatments：methyl jasmonate（MeJA）,abscisic acid（ABA） and salicylic acid（SA）.Real time qPCR revealed that wounding and H_2O_2 induced the expressions of all the five genes.Only CmLOX08 was induced by cold while only CmLOX13 was suppressed by high temperature.ABA induced the expressions of CmLOXIO and CmLOX12 while inhibited CmLOX13 and CmLOX18.MeJA increased the 3 genes expressions except CmLOX08 and CmLOX13,whereas SA decreased the effect,apart from CmLOX12.All the abiotic stresses and signal molecules treatments increased the LOX activity in leaves of oriental melon.In summary,the results suggest that the five genes have diverse functions in abiotic stress and hormone responses,and might participate in defense response.The data generated in this study will be helpful in subcellular localization and transgenic experiment to understand their precise roles in plant defense response.

Growth promotion of interspecific hybrid embryos between Cucumis anguria and Melon(C. melo) by fruit heating

Wild species of the genus Cucumis, such as C. anguria, are resistant to various melon(C. melo) diseases such as Fusarium wilt race 1.2 and are anticipated as genetic resources of melon. However, in the interspecific crosses between C. anguria and melon, the abortion of the embryos was observed in the early growth stage and could not be regenerated even when cultured. Therefore, for embryo rescue, it is necessary to promote embryo growth during abortion occurrence. This study investigated the effects of fruit heating on embryo growth in interspecific hybrids of C. anguria and melon. In the heating device, the minimum night temperature around the fruit was maintained above 21.5 °C. The ovule grain area of C. anguria × MR-1 with fruit heating was significantly enlarged compared to that without fruit-heating. It was also significantly enlarged compared with the ovule grain area of C. anguria self-pollination. Although, in C. anguria × MR-1 without fruit-heating, no embryo was observed until 10 days after pollination(DAP), and pre-embryos were observed at 13 DAP. Conversely, in C. anguria × MR-1 with fruit-heating, pre-embryos were even observed at 10 DAP. These results suggest that the possibility of embryo or ovule culture regeneration has increased due to embryo growth promotion.

Genome-Wide Identification of Two-Component Signal Transduction System Genes in Melon (<I>Cucumis melon</I>L.)

Two-component system (TCS) is responsible for cytokinin signaling, which plays critical roles in plant development and physiological process. This system is generally composed of two signaling factors, a histidine kinase (HK) and a response regulator (RR) that is associated with a histidine phosphotransfer (HP) protein. In this study, we performed systematic investigation on TCS genes in melon (Cucumis melon L.). We identified 44 TCS genes in melon, including 18 HK(L)s (9 HKs and 9 HKLs), 5 HPs (4 authentic and 1 pseudo), and 21 RRs (7 Type-A, 8 Type-B, and 6 pseudo). The classification and structure of these melon TCS members were introduced in detail as well. Our results provided new insights into the characteristics of the melon TCS genes and might benefit their functional study in future.

Genome-wide characterization of graft-transmissible mRNA-coding P450 genes of cucumber(Cucumis sativus L.)

P450(cytochrome P450)is a supergene family,which is involved in various metabolic pathways in plants.Based on previous study,we found some of cucumber P450 mRNAs were systemic mobile in cucumber/pumpkin grafts.However,the reason that why P450 mRNAs were endorsed as signaling,and what specific motif(s)did they harbored is not clear yet.Here,we first identified 221 CsaP450 genes in cucumber genomewide level.Combining with graft-transmissiblemRNAs datasets in cucumber,we elucidated 15mobile-CsaP450-coding genes,of which 5 and 10 belonged to A-type and non-A type respectively.Compared with Arabidopsis and pumpkin(Cucubit moschata)graft-induced-transmissible P450 mRNAs,a phylogenetic treewas constructed and divided into eight clans by usingmultiple-sequence alignment.Gene ontology(GO)enrichment and Kyoto Encyclopedia of Genes and Genomes(KEGG)annotations indicated that the expression patterns of the mobile-mRNA-coding CsaP450 genes in different tissues of cucumber was specifically enriched in oxidoreductase activity and secondary metabolic pathways.The structures and motifs of these 15 mobile-mRNA-coding CsaP450 genes and their types of regulatory elements told that the proportion of CU-rich motifs was higher than nonmobile-mRNA-coding CsaP450 genes.The integrated analysis of mobility direction and mRNA abundance of 15 mobilemRNA-coding CsaP450 genes allowed to conclude that there was rarely relationship between them.The study provided a new insight into the relationship between the motifs and functional characterization of mobile-mRNA-coding P450 genes of cucumber in genome-wide levels.

Effects of Meteorological Conditions on Yield and Quality of Facility Hami Melon

With different varieties of facility Hami melon(Cucumis melo var. sacchairinus) as test materials, the effects of meteorological conditions on the yield and quality of different varieties of facility Hami melon were analyzed. The results showed that among the yield and quality traits of melon, the variation degree of average single melon weight was the highest, and the coefficient of variation was 33.05%. The variation degree of leaf area index was the lowest, and the coefficient of variation was 11.00%. Through the correlation analysis of meteorological factors with the yield and quality of facility Hami melon, it was found that the quality traits of facility Hami melon were significantly positively correlated with maximum temperature and sunshine duration, and significantly negatively correlated with precipitation. The yield traits were positively correlated with maximum temperature, sunshine duration and precipitation.

The Study of Allelochemicals of the Melon Fly (Myiopardalis pardalina Bigot.)

This study describes the isolation, identification of allelochemicals of the melon fly (Myiopardalis pardalina Bigot.), using the GC-MS method. A food attractant has been identified and a method for the synthesis of its synthetic analogue has been developed. Also, a route for the synthesis of para pheromone, raspberry ketone, has been proposed.

QTL Analysis of Traits Related to Melon Stigma and Ovary Size

The melon varieties MR-1 and M4-7 were used as the parent materials to produce hybrids.A total of 170 F2 individuals were used as the mapping population to construct a genetic linkage map.In this study,240 cleaved amplified polymorphism sequence(CAPS)molecular markers were developed,and 105 of which showed polymorphism between parents.The map contained 105 markers grouped into 12 linkage groups,spanning a total length of 1998.85 cM,with an average length of 19.04 cM between markers.The composite interval mapping(CIM)method was used to detect QTLs related with melon stigma and ovary traits:stigma longitudinal diameter(STLD),stigma transverse diameter(STTD),stigma weight(STW),ovary longitudinal diameter(OLD),and ovary transverse diameter(OTD).A total of nine QTLs were identified:six for stigma size and three for ovary size.A total of six loci were detected for stigma size,which included two loci for stigma longitudinal diameter,two loci for stigma transverse diameter,and two loci for stigma weight.The major effective locus regulating stigma transverse diameter was qSTTD-9-1.A total of three loci were identified for ovary size traits,including one locus for ovary longitudinal diameter and two loci for ovary transverse diameter.

SLAF marker based QTL mapping of fruit-related traits reveals a major-effect candidate locus ff2.1 for flesh firmness in melon

Flesh firmness(FF) is an important and complex trait for melon breeders and consumers. However, the genetic mechanism underlying FF is unclear. Here, a soft fruit melon(P5) and a hard fruit melon(P10) were crossed to generate F2, and the FF and fruit-related traits were recorded for two years. By performing quantitative trait locus(QTL) specificlocus amplified fragment(SLAF)(QTL-SLAF) sequencing and molecular marker-linkage analysis, 112 844 SLAF markers were identified, and 5 919 SNPs were used to construct a genetic linkage map with a total genetic distance of1 356.49 cM. Ten FF-and fruit-related QTLs were identified. Consistent QTLs were detected for fruit length(FL) and fruit diameter(FD) in both years, and QTLs for single fruit weight(SFW) were detected on two separate chromosomes in both years. For FF, the consistent major locus(ff2.1) was located in a 0.17-Mb candidate region on chromosome 2. Using 429 F2individuals derived from a cross between P5 and P10, we refined the ff2.1 locus to a 28.3-kb region harboring three functional genes. These results provide not only a new candidate QTL for melon FF breeding but also a theoretical foundation for research on the mechanism underlying melon gene function.

Characterization and discrimination of fermented sweet melon juice by different microbial strains via GC-IMS-based volatile profiling and chemometrics

The main purpose of this study was to investigate the effect of different lactic acid bacteria and yeast strains on the volatile composition of fermented sweet melon juice.Headspace gas chromatography-ion mobility spectrometry(HS-GC-IMS)coupled with chemometrics was performed to identify the potential volatiles for the discrimination of different fermented sweet melon juice.In total,70 volatile compounds were found in the fermented sweet melon juices.Of them,45 compounds were annotated according to the GC-IMS database and classified into esters,alcohols,aldehydes,ketones and furans.Results from the multivariate analysis reveal that sweet melon juice fermented by different combinations of microbial strains could be distinctly separated from each other.A total of 15 volatiles with both variable importance in projection value>1 and P<0.05 were determined as potential markers for the discrimination of fermented sweet melon juice.This study confirms the effect of microorganisms on the flavor of the fermented sweet melon juice and shows the potential of HS-GC-IMS combined with chemometrics as a powerful strategy to obtain volatile fingerprints of different fermented sweet melon juice.

CT三维重建在桡骨远端骨折Melone分型及术后效果评估中的价值研究

目的 探讨分析在桡骨远端骨折Melone分型及其术后效果评估中CT三维重建的应用价值研究。方法 选取2020年6月至2022年6月收治的58例桡骨远端骨折患者作为研究对象,所有患者治疗前均进行X线及CT检查,以术中探查诊断结果为“金标准”。比较两种检查方式在桡骨远端骨折Melone分型中的诊断阳性率,不同分型中的解剖复位、内固定置入质量及治疗后3个月时的腕关节功能评分。结果 CT三维重建在桡骨远端骨折Melon分型中的诊断阳性率为91.38%显著高于X线检查的72.41%(P<0.05)。术后效果评估通过观察解剖复位及内固定置入质量的检出率,CT三维重建在各分型的检出率均显著高于X线(P<0.05)。术后3个月时,CT三维重建在腕关节功能评分优、良的检出率高于X线(P<0.05),而在可、差检出率比较无差异(P>0.05)。结论 CT三维重建在桡骨远端骨折Melone分型、术后解剖复位质量及内固定置入质量中具有较高的诊断准确率,同时,桡骨远端骨折患者术后腕关节功能与影像学的评估中,CT三维重建对腕关节功能的敏感性更强,更加能够准确的评估。

Exploring the mechanism of action bitter melon in the treatment ofbreast cancer by network pharmacology

BACKGROUND Bitter melon has been used to stop the growth of breast cancer(BRCA)cells.However,the underlying mechanism is still unclear.AIM To predict the therapeutic effect of bitter melon against BRCA using network pharmacology and to explore the underlying pharmacological mechanisms.METHODS The active ingredients of bitter melon and the related protein targets were taken from the Indian Medicinal Plants,Phytochemistry and Therapeutics and SuperPred databases,respectively.The GeneCards database has been searched for BRCA-related targets.Through an intersection of the drug’s targets and the disease’s objectives,prospective bitter melon anti-BRCA targets were discovered.Gene ontology and kyoto encyclopedia of genes and genomes enrichment analyses were carried out to comprehend the biological roles of the target proteins.The binding relationship between bitter melon’s active ingredients and the suggested target proteins was verified using molecular docking techniques.RESULTS Three key substances,momordicoside K,kaempferol,and quercetin,were identified as being important in mediating the putative anti-BRCA effects of bitter melon through the active ingredient-anti-BRCA target network study.Heat shock protein 90 AA,proto-oncogene tyrosine-protein kinase,and signal transducer and activator of transcription 3 were found to be the top three proteins in the proteinprotein interaction network study.The several pathways implicated in the anti-BRCA strategy for an active component include phosphatidylinositol 3-kinase/protein kinase B signaling,transcriptional dysregulation,axon guidance,calcium signaling,focal adhesion,janus kinase-signal transducer and activator of transcription signaling,cyclic adenosine monophosphate signaling,mammalian CONCLUSION Overall,the integration of network pharmacology,molecular docking,and functional enrichment analyses shed light on potential mechanisms underlying bitter melon’s ability to fight BRCA,implicating active ingredients and protein targets,as well as highlighting the major signaling pathways that may be altered by this natural product for therapeutic benefit.

Intellectual Property Protection and High-Quality Development of Xinjiang Melons under the Big Food Concept

The development of diversified foods such as melons under the big food concept can reduce the pressure on staple food grain.Xinjiang has the advantages of building a new development pattern of dual circulation of diversified food industry and establishing a national diversified food safety and high-quality assurance center.The construction of an agricultural power needs the strategic support of an intellectual property power.This paper introduced and studied Xinjiang s melon industry and its agricultural intellectual property resources,analyzed the six main problems,including many idle land resources have not been developed into melon fields and the role of melons in diversified food supply systems not well played.Finally,it proposed to vigorously develop diversified food industries such as melons in Xinjiang and establish an eight-point strategy such as national diversified food safety and high-quality assurance center.