Watermelon(Citrullus lanatus) is sensitive to salt stress. For breeding applications, it is of great significance to explore the genetic mechanism underlying salt tolerance in watermelon by analyzing the dehydration r...Watermelon(Citrullus lanatus) is sensitive to salt stress. For breeding applications, it is of great significance to explore the genetic mechanism underlying salt tolerance in watermelon by analyzing the dehydration responsive element-binding(DREB) factor family members.However, they are rarely studied in watermelon. In this study, we identified ClaDREB gene family members in watermelon based on whole genome data;analyzed the physicochemical properties, evolution, and phylogeny;and studied their expression patterns under salt stress in two watermelon varieties with varying salt tolerance. In total, 57 DREB family members were identified in watermelon, and most of them were located in the nucleus. ClaDREBs were divided into six subgroups Ⅰ-Ⅵ. The promoter region of ClaDREBs from subgroup Ⅱ contained many defense-related and stress responsive elements. Among them, ClaDREB14 was significantly upregulated by salt stress and exhibited differential expression in salt-tolerant and salt-sensitive varieties. Moreover, overexpression of ClaDREB14 in watermelon roots significantly improved the salt tolerance of transgenic plants;mainly, it significantly increased the activities of POD, SOD, and CAT and significantly reduced MDA content.However, the results from gene-edited watermelon roots obtained using CRISPR/Cas9 vectors showed the opposite trend. Furthermore, we demonstrated that ClaDREB14 directly binds to the cis-acting element ACCGAC in the promoter region of ClaPOD6 and promotes its expression.Therefore, ClaDREB14 may enhance salt tolerance by increasing the activity of antioxidant enzymes in watermelon roots. This study provided valuable information on the DREB gene family in watermelon and laid the foundation for future functional validation and genetic engineering applications.展开更多
Nondestructive measurement technology of phenotype can provide substantial phenotypic data support for applications such as seedling breeding,management,and quality testing.The current method of measuring seedling phe...Nondestructive measurement technology of phenotype can provide substantial phenotypic data support for applications such as seedling breeding,management,and quality testing.The current method of measuring seedling phenotypes mainly relies on manual measurement which is inefficient,subjective and destroys samples.Therefore,the paper proposes a nondestructive measurement method for the canopy phenotype of the watermelon plug seedlings based on deep learning.The Azure Kinect was used to shoot canopy color images,depth images,and RGB-D images of the watermelon plug seedlings.The Mask-RCNN network was used to classify,segment,and count the canopy leaves of the watermelon plug seedlings.To reduce the error of leaf area measurement caused by mutual occlusion of leaves,the leaves were repaired by CycleGAN,and the depth images were restored by image processing.Then,the Delaunay triangulation was adopted to measure the leaf area in the leaf point cloud.The YOLOX target detection network was used to identify the growing point position of each seedling on the plug tray.Then the depth differences between the growing point and the upper surface of the plug tray were calculated to obtain plant height.The experiment results show that the nondestructive measurement algorithm proposed in this paper achieves good measurement performance for the watermelon plug seedlings from the 1 true-leaf to 3 true-leaf stages.The average relative error of measurement is 2.33%for the number of true leaves,4.59%for the number of cotyledons,8.37%for the leaf area,and 3.27%for the plant height.The experiment results demonstrate that the proposed algorithm in this paper provides an effective solution for the nondestructive measurement of the canopy phenotype of the plug seedlings.展开更多
Genotyping by Target Sequencing(GBTS)technology,known for its flexibility,high efficiency,high throughput,and low cost,has been increasingly employed in molecular breeding.However,there is still limited study on the d...Genotyping by Target Sequencing(GBTS)technology,known for its flexibility,high efficiency,high throughput,and low cost,has been increasingly employed in molecular breeding.However,there is still limited study on the design and development of high-throughput genotyping tools in watermelon.In this study,we identified 112000 high quality SNPs by analyzing the resequencing data of 43 cultivated watermelon accessions.11921 and 6094 SNPs were selected for developing two sets of watermelon liquid-phase chips with different marker densities,named Watermelon 10K and 5K,respectively.Furthermore,the SNPs and Indels of most mapped gene/QTLs for many agronomic important traits in watermelon were also integrated into the two chips for foreground selection.These chips have been tested using GBTS technology in various applications in watermelon.The genotyping of 76 accessions by Watermelon 5K liquid-phase chip showed an average detection rate of 99.28%and 81.78%for cultivated and wild watermelon accessions,respectively.This provided enough markers information for GWAS and two significant QTLs,ssc1.1 and ssc1.2,associated with soluble sugar content were detected.Furthermore,BSA-seq analysis for non-lobed leaf and dwarf traits were validated by liquid-phase chips,and the candidate region was consistent with our previous studies.Additionally,we precisely introduced the Cldw1 and Clbl genes into an elite inbred line WT2 using Watermelon 5K for assisted selection,resulting in the development of three new germplasm with good plant architecture.As a high-throughput genotyping liquid-phase SNP array,the Watermelon 10K and 5K chips will greatly facilitate functional studies and molecular breeding in watermelon.展开更多
As a prerequisite for sexual reproduction,gametophyte development is an interesting process involving cell proliferation,differentiation and specialization.Gametogenesis has been extensively explored in model plants,b...As a prerequisite for sexual reproduction,gametophyte development is an interesting process involving cell proliferation,differentiation and specialization.Gametogenesis has been extensively explored in model plants,but the regulatory mechanism of gametophyte development largely remains unknown in Cucurbitaceae species.In present study,we have shown that watermelon ClBBM and ClPLT2,two AP2/ERF transcription factors,participated in both male and female gametophyte development.Clbbm and Clplt2 single mutants resembled wild-type phenotypes in both vegetative and reproductive development.But Clbbm/Clplt2 double mutant showed partial pollen abortion and bore less seeds comparing to WT.Our results indicated that the abnormal pollen grains were caused by premature tapetum degeneration,and reduced seed-set was due to faulty embryo sac development.ClBBM and ClPLT2 were expressed in FG4 embryo sacs,and their transcripts were also detectable in the tapetum and microspore of stage 9 anthers,which was consistent with developmental stages of defective phenotypes observed in double mutant.The expression of genes essential for tapetum development,ClATM1,ClAMS,ClMS1 and ClMS188,was decreased in Clbbm/Clplt2 double mutants.Moreover,the transcriptome analysis indicated that ClBBM and ClPLT2 participated in tapetum and pollen wall development by regulate cell cycle,transmembrane transport,glucan and cellulose metabolic process.Collectively,ClBBM and ClPLT2 were functionally redundant in regulating gametophyte development in watermelon,and their functions differ from their homologous genes in model plant Arabidopsis.展开更多
Watermelon(Citrullus lanatus)is an economically important horticultural crop.However,it is susceptible to lowtemperature stress,which significantly challenges its production and supply.Despite the great economic impor...Watermelon(Citrullus lanatus)is an economically important horticultural crop.However,it is susceptible to lowtemperature stress,which significantly challenges its production and supply.Despite the great economic importance of watermelon,little is known about its response to low-temperature stress at the transcriptional level.In this study,we performed a time-course transcriptome analysis to systematically investigate the regulatory network of watermelon under low-temperature stress.Six low-temperature-responsive gene clusters representing six expression patterns were identified,revealing diverse regulation of metabolic pathways in watermelon under lowtemperature stress.Analysis of temporally specific differentially expressed genes revealed the time-dependent nature of the watermelon response to low temperature.Moreover,ClMYB14 was found to be a negative regulator of low-temperature tolerance as ClMYB14-OE lines were more susceptible to low-temperature stress.Co-expression network analysis demonstrated that ClMYB14 participates in the low-temperature response by regulating the unsaturated fatty acid pathway and heat shock transcription factor.This study provides substantial information for understanding the regulatory network of watermelon in response to low-temperature stress,and identifies candidate genes for the genetic improvement of watermelon with higher low-temperature tolerance.展开更多
The color and pattern of watermelon rind are crucial external traits that directly affect consumer preferences.Watermelons with stripes having a stronger color than the background rind are ideal for studying stripe pa...The color and pattern of watermelon rind are crucial external traits that directly affect consumer preferences.Watermelons with stripes having a stronger color than the background rind are ideal for studying stripe patterns in plants,while there is still limited knowledge about the genetic mechanisms underlying stripe coloration due to the lack of germplasm resources.In this study,we focused on a watermelon germplasm with colorless stripes,and genetic analysis revealed that the trait is controlled by a single recessive gene.The gene Clsc(Citrullus lanatus stripe coloration),which is responsible for the colorless stripe,was localized into a 147.6 kb region on Chr9 by linkage analysis in a large F2 mapping population.Further analysis revealed that the Cla97C09G175170 gene encodes the APRR2 transcription factor,plays a crucial role in determining the watermelon colorless stripe phenotype and was deduced to be related to chlorophyll synthesis and chloroplast development.Physiological experiments indicated that Cla97C09G175170 may significantly influence chloroplast development and chlorophyll synthesis in watermelon.The results of this study provide a better understanding of the molecular mechanism of stripe coloration in watermelon and can be useful in the development of marker-assisted selection(MAS)for new watermelon cultivars.展开更多
Watermelon(Citrullus lanatus),one of the top five fruit crops based on the gross tonnage and cultivated area globally,holds major economic importance in agriculture and contributes substantially to farmers’incomes.Wa...Watermelon(Citrullus lanatus),one of the top five fruit crops based on the gross tonnage and cultivated area globally,holds major economic importance in agriculture and contributes substantially to farmers’incomes.Watermelon cultivation relies on sexual reproduction,with meiosis playing a pivotal role in this process.However,our understanding of the meiotic mechanism in watermelon remains limited.In this study,we utilized CRISPR/Cas9 technology to target ClDYAD,a homolog of the meiosis-related genes AtDYAD and OsAM1,and conducted functional analysis to explore the initiation of meiosis in watermelon.ClDYAD was highly expressed in tender male flowers both before and during the early stages of meiosis.Mutations in ClDYAD led to meiotic arrest at the leptotene stage,impeding the normal enlargement of microspore mother cells and megasporocytes.This resulted in the absence of pollen in anthers and seed abortion.ClDYAD physically interacts with the protein encoded by Cla97C07G137480,which was identified as a switch-associated protein 70-like protein(ClSWAP-70).The expression pattern of ClSWAP-70 in tender male flowers of various sizes matched with the changes in ClDYAD mRNA levels.These findings shed light on the molecular mechanisms governing the initiation of meiosis in watermelon,offering valuable insights into male and female sterility in Cucurbitaceae plants and guiding future research.展开更多
[Objective] The aim of this study was to screen bacteria strains with stable antagonistic effect against watermelon fusarium wilt from soil and investigate the biological control of watermelon fusarium wilt by applyin...[Objective] The aim of this study was to screen bacteria strains with stable antagonistic effect against watermelon fusarium wilt from soil and investigate the biological control of watermelon fusarium wilt by applying the antagonistic bacteria strains into soil.[Method] Actinomycete strains,fluorescent bacteria strains and bacillus strains were isolated from soil samples by the dilution-plate method,then its resistance was screened respectively by the improved confront culture method after colonies were purified.Finally,bacteria strains with better antagonistic effect were identified.[Result] 29 bacteria strains with stable antagonistic effect against watermelon fusarium wilt were screened from 39 soil samples,which contained 15 fluorescent bacteria strains,5 bacillus strains and 9 actinomycete strains.Furthermore,three antagonistic bacteria strains of FM2,FM3 and FM4 with the strongest antagonism were identified primarily.[Conclusion] According to cultural characteristics,morphological observation,biochemical and physiological tests,FM2 belongs to bacillus subtilis,while FM3 and FM4 belong to micrococcus.展开更多
The identification of germplasm is an important step for effective utilization of the available germplasm. In previous studies, isoenzyme, RAPD and SSR techniques had been used to conduct the genetic identification of...The identification of germplasm is an important step for effective utilization of the available germplasm. In previous studies, isoenzyme, RAPD and SSR techniques had been used to conduct the genetic identification of watermelon ( Citrullus lanatus (Thunb.) Mansf.), but their effectiveness was limited due to the extremely narrow genetic background among watermelon genotypes. In this research, amplified fragment length polymorphism (AFLP), which was reported as a reliable technique with high efficiency in detecting polymorphism, was used to conduct genetic analysis and variety identification of thirty genotypes of watermelon core collection that represent a wide range of breeding and commercially available germplasm. As a result, a DNA fingerprint based on 15 bands amplified with four primer combinations was developed. In this fingerprint, each genotype has its unique fingerprint pattern and can be distinguished from each other. Furthermore, in or der to facilitate the utilization of AFLP marker in practice, one specific AFLP band of genotype 'PI296341' coming from fragment amplified by primer combination E-AT/M-CAT was successfully converted into a sequence characterized amplified region (SCAR) marker.展开更多
This study was conducted to investigate the effects of interplanting of sugarcane with watermelon and soybean on agronomic traits, yields, quality and benefit of crops, so as to provide reference for extension of the ...This study was conducted to investigate the effects of interplanting of sugarcane with watermelon and soybean on agronomic traits, yields, quality and benefit of crops, so as to provide reference for extension of the interplanting mode of sugarcane with watermelon or soybean. There were 4 treatments： CK1 （sole planting of sugarcane, no fertilization）, CK2 （sole planting of sugarcane, applying chemical fertilizers）, T1 （interplanting sugarcane with watermelon, applying chemical fertilizers ＋ cow dung）, and T2 （interplanting sugarcane with soybean, applying chemical fertilizers ＋ cow dung）. The results showed that compared with CK2, the sugarcane yield of treatment T1 reached 2.5 t/hm2, the watermelon yield was 1.02 t/hm2, and the total economic benefit increased by 3090 Yuan/hm2; the sugarcane yield in treatment T2 decreased by 7.61 t/hm2 （but not significant）, and the soybean yield was 0.35 t/hm2, and the total economic benefit increased by 720 Yuan/hm2; and the total sugar content in watermelon flesh was 8.59%, and the crude protein content in soybean was 36.15%, satisfying the quality indexes of the same agricultural products. Compared with sole planting of sugarcane, sugarcane plus watermelon or soybean interplanting mode improved economic benefit, treatment T1 showed economic benefit far higher than treatment T2, and is suitable for sugarcane regions with good water and fertilizer conditions and enough labor, and the T2 mode has simple operation, and is suitable for large-area extension.展开更多
[Objective] This study investigated the spatial characteristics of counties （cities） with comparative advantages in watermelon and melon production to provide reference bases in formulating strategies for the develo...[Objective] This study investigated the spatial characteristics of counties （cities） with comparative advantages in watermelon and melon production to provide reference bases in formulating strategies for the development of watermelon and melon industries in Hainan Province. [Method] By using the sowing area, total yield, and yield per unit area of watermelon and melon in Hainan Province as research u- nits, the yield comparative advantage （YCA）, efficiency comparative advantage （E- CA）, scale comparative advantage （SCA）, concentration ratio comparative advantage （CRCA）, comprehensive comparative advantage （CCA）, ratio of yield per unit area （RYPA）, sowing area ratio （SAR）, and distribution characteristics of watermelon and melon were systematically analyzed. By referring to the agricultural statistic data of 18 counties （cities） in Hainan Province, indexes for each research unit （i.e., the YCA index, ECA index, SCA index, CRCA index, CCA index, RYPA index, and SAR index） were established and calculated to determine the comparative advantage of watermelon and melon production in Hainan Province. A spatial expression of the research result on a map was conducted by using GIS software. [Result] Seven counties （cities） exhibited comparative advantages in watermelon production, namely, Lingshui, Wanning, Wenchang, Dongfang, Sanya, Ledong, and Changjiang. The Eastern and Southern Hainan Provinces had CCAs, and the Western and Northern Hainan Provinces could be reserved for future development. For melon production, four counties （cities） exhibited comparative advantages, namely, Ledong, Lingshui, Sanya, and Dongfang. The Southern Hainan Province had CCA, whereas the West- ern Hainan Province could be reserved for later development. [Conclusion] The result has showed that establishing watermelon and melon as dominant agricultural prod- ucts is necessary for the future development of the industry and for the formulation of a layout of regions with advantages, where key support and construction should be provided preferentially with the aim to raise the yield, quality, and market com- petitiveness of products.展开更多
Watermelon, as a traditional dominant crop in Beijing, has obvious indus- trial advantages. The mixed substrate soilless cultivation techniques developed by the Beijing Agricultural Technology Extension Station for mi...Watermelon, as a traditional dominant crop in Beijing, has obvious indus- trial advantages. The mixed substrate soilless cultivation techniques developed by the Beijing Agricultural Technology Extension Station for mini watermelon in spring greenhouse can effectively solve the problem of continuous cropping in facility wa- termelon, and they are conducive to green, safe and efficient development of water- melon industry for fixed nutrient solution formula, automatic water and fertilizer irri- gation, stable product quality and facilitating large-scale and standardized production.展开更多
[Objective]This study aimed to clarify the spatial patterns of comparative advantage of watermelon production in Guangxi Zhuang Autonomous Region, to pro-vide theoretical basis for the development of watermelon indust...[Objective]This study aimed to clarify the spatial patterns of comparative advantage of watermelon production in Guangxi Zhuang Autonomous Region, to pro-vide theoretical basis for the development of watermelon industry in China. [Method] Based on the agricultural statistics data of Guangxi and al over China, yield com-parative advantage （YCA） index, efficiency comparative advantage （ECA） index, scale comparative advantage （SCA） index, concentration ratio comparative advantage （CRCA） index, comprehensive comparative advantage （CCA） index, ratio of yield per unit area （RYPA） index and sowing area ratio （SAR） index were established and calculated to determine the watermelon production comparative advantages in 31 provinces （cities） in China. Spacial patterns of the comparative advantages were produced by using GIS software. [Result] Nine provinces Shandong, Henan, Anhui, Hebei, Hubei, Jiangsu, Hunan, Zhejiang and Guangxi were the dominant regions in watermelon production al over the country. The Central and Eastern China showed the integrated comparative advantage in watermelon production, while the Southern, Northeastern, Northern and Northwestern China can be considered as the potential places for watermelon production in future. Southwest China gave more priority to watermelon production, so the comparative advantages kept increasing here. [Con-clusion] Based on this study, watermelon production should be a prior consideration among the agricultural products in Guangxi. Related measures should be developed to optimize the regional distribution of watermelon in Guangxi and China to promote healthy competition in watermelon production.展开更多
[Objective] This study was conducted to reveal the effect of exogenous calcium （Ca） in mitigating the damage caused by NaCI stress to watermelon seedlings. [Method] To the liquid medium containing 100 mmol/L NaCI, C...[Objective] This study was conducted to reveal the effect of exogenous calcium （Ca） in mitigating the damage caused by NaCI stress to watermelon seedlings. [Method] To the liquid medium containing 100 mmol/L NaCI, CaSO4 was added to the final concentrations of 4, 6, 10 and 14 mmol/L. The morphological and physiological indices including plant height, stem diameter, number of leaves per plant, maximum leaf length, maximum leaf width, seedling fresh weight and dry weight, malondialdehyde （MDA） content, relative permeability of plasma membrane, ascorbic acid （AsA） content, free proline content, soluble sugar content and soluble protein content in leaves of the seedlings treated with above media for 10 d were measured. [Result] NaCI stress significantly inhibited the growth of watermelon seedlings. The membrane permeability and MDA content in leaves were significantly increased under NaCI stress, and the contents of proline, soluble sugar, soluble protein and AsA were increased to different extents. Exogenous CaSO4 influenced the morphological and physiological indices of seedlings under NaCI stress in a manner. Treated with 6 mmol/L CaSO4, the growth of seedlings under salinity was significantly improved; membrane permeability and MDA content were drastically reduced, the contents of proline, soluble sugar, soluble pro- tein and AsA in leaves were significantly increased. [Conclusion] Exogenous CaSO＋ alleviates lipid peroxidation and inhibition of seedling growth under NaCI stress by improving the abilities of antioxidation and osmotic adjustment, and 6 mmol/L CaSO4 showed the best effect.展开更多
基金funded by grants fromthe China Agriculture Research System of MOF and MARA(CARS-25)the Key Research and Development Program of Xinjiang Uygur autonomous region(Grant No.2023B02017)+3 种基金the Agricultural Science and Technology Innovation Program(CAAS-ASTIP-2021-ZFRI,CAAS-ASTIP-2024-WRI)the Basic Research Funds of Chinese Academy of Agricultural Sciences(Grant No.1610192023201)Natural Science Foundation of Henan Province(Grant No.252300421694)Joint Research on Agricultural Variety Improvement of Henan Province(Grant No.2022010503).
文摘Watermelon(Citrullus lanatus) is sensitive to salt stress. For breeding applications, it is of great significance to explore the genetic mechanism underlying salt tolerance in watermelon by analyzing the dehydration responsive element-binding(DREB) factor family members.However, they are rarely studied in watermelon. In this study, we identified ClaDREB gene family members in watermelon based on whole genome data;analyzed the physicochemical properties, evolution, and phylogeny;and studied their expression patterns under salt stress in two watermelon varieties with varying salt tolerance. In total, 57 DREB family members were identified in watermelon, and most of them were located in the nucleus. ClaDREBs were divided into six subgroups Ⅰ-Ⅵ. The promoter region of ClaDREBs from subgroup Ⅱ contained many defense-related and stress responsive elements. Among them, ClaDREB14 was significantly upregulated by salt stress and exhibited differential expression in salt-tolerant and salt-sensitive varieties. Moreover, overexpression of ClaDREB14 in watermelon roots significantly improved the salt tolerance of transgenic plants;mainly, it significantly increased the activities of POD, SOD, and CAT and significantly reduced MDA content.However, the results from gene-edited watermelon roots obtained using CRISPR/Cas9 vectors showed the opposite trend. Furthermore, we demonstrated that ClaDREB14 directly binds to the cis-acting element ACCGAC in the promoter region of ClaPOD6 and promotes its expression.Therefore, ClaDREB14 may enhance salt tolerance by increasing the activity of antioxidant enzymes in watermelon roots. This study provided valuable information on the DREB gene family in watermelon and laid the foundation for future functional validation and genetic engineering applications.
基金funded by the National Key Research and Development Program of China(Grant No.2019YFD1001900)the HZAU-AGIS Cooperation Fund(Grant No.SZYJY2022006).
文摘Nondestructive measurement technology of phenotype can provide substantial phenotypic data support for applications such as seedling breeding,management,and quality testing.The current method of measuring seedling phenotypes mainly relies on manual measurement which is inefficient,subjective and destroys samples.Therefore,the paper proposes a nondestructive measurement method for the canopy phenotype of the watermelon plug seedlings based on deep learning.The Azure Kinect was used to shoot canopy color images,depth images,and RGB-D images of the watermelon plug seedlings.The Mask-RCNN network was used to classify,segment,and count the canopy leaves of the watermelon plug seedlings.To reduce the error of leaf area measurement caused by mutual occlusion of leaves,the leaves were repaired by CycleGAN,and the depth images were restored by image processing.Then,the Delaunay triangulation was adopted to measure the leaf area in the leaf point cloud.The YOLOX target detection network was used to identify the growing point position of each seedling on the plug tray.Then the depth differences between the growing point and the upper surface of the plug tray were calculated to obtain plant height.The experiment results show that the nondestructive measurement algorithm proposed in this paper achieves good measurement performance for the watermelon plug seedlings from the 1 true-leaf to 3 true-leaf stages.The average relative error of measurement is 2.33%for the number of true leaves,4.59%for the number of cotyledons,8.37%for the leaf area,and 3.27%for the plant height.The experiment results demonstrate that the proposed algorithm in this paper provides an effective solution for the nondestructive measurement of the canopy phenotype of the plug seedlings.
基金supported by the National Natural Science Foundation of China(Grant Nos.32172602,32472739)the Major Science and Technology Project of Henan Province(Grant No.221100110400)+3 种基金the Funding of Joint Research on Agricultural Varietie Improvement of Henan Province(Grant No.2022010503)the Natural Science Foundation of Henan(Grant No.242300421030)the Key Scientifc and Technological Project of Henan Province(Grant Nos.242102111124,242102111115)the Key Research and Development Program of Xinjiang Uygur autonomous region(2023B02017-2).
文摘Genotyping by Target Sequencing(GBTS)technology,known for its flexibility,high efficiency,high throughput,and low cost,has been increasingly employed in molecular breeding.However,there is still limited study on the design and development of high-throughput genotyping tools in watermelon.In this study,we identified 112000 high quality SNPs by analyzing the resequencing data of 43 cultivated watermelon accessions.11921 and 6094 SNPs were selected for developing two sets of watermelon liquid-phase chips with different marker densities,named Watermelon 10K and 5K,respectively.Furthermore,the SNPs and Indels of most mapped gene/QTLs for many agronomic important traits in watermelon were also integrated into the two chips for foreground selection.These chips have been tested using GBTS technology in various applications in watermelon.The genotyping of 76 accessions by Watermelon 5K liquid-phase chip showed an average detection rate of 99.28%and 81.78%for cultivated and wild watermelon accessions,respectively.This provided enough markers information for GWAS and two significant QTLs,ssc1.1 and ssc1.2,associated with soluble sugar content were detected.Furthermore,BSA-seq analysis for non-lobed leaf and dwarf traits were validated by liquid-phase chips,and the candidate region was consistent with our previous studies.Additionally,we precisely introduced the Cldw1 and Clbl genes into an elite inbred line WT2 using Watermelon 5K for assisted selection,resulting in the development of three new germplasm with good plant architecture.As a high-throughput genotyping liquid-phase SNP array,the Watermelon 10K and 5K chips will greatly facilitate functional studies and molecular breeding in watermelon.
基金supported by the National Youth Talent Program(Grant No.A279021801)Key-Area R&D Program of Guangdong Province(Grant No.2022B0202060001)+3 种基金Science and Technology Innovation Team of Shaanxi(Grant No.2021TD-32)the Natural Science Foundation of Shaanxi Province(Grant Nos.2021JM-089,2022JM112 and 2022JQ-162)the Key R&D Project from Yangling Seed Industry Innovation Center(Grant No.K3031322016)Fundamental Research Funds for the Central Universities(Grant No.2452022111)。
文摘As a prerequisite for sexual reproduction,gametophyte development is an interesting process involving cell proliferation,differentiation and specialization.Gametogenesis has been extensively explored in model plants,but the regulatory mechanism of gametophyte development largely remains unknown in Cucurbitaceae species.In present study,we have shown that watermelon ClBBM and ClPLT2,two AP2/ERF transcription factors,participated in both male and female gametophyte development.Clbbm and Clplt2 single mutants resembled wild-type phenotypes in both vegetative and reproductive development.But Clbbm/Clplt2 double mutant showed partial pollen abortion and bore less seeds comparing to WT.Our results indicated that the abnormal pollen grains were caused by premature tapetum degeneration,and reduced seed-set was due to faulty embryo sac development.ClBBM and ClPLT2 were expressed in FG4 embryo sacs,and their transcripts were also detectable in the tapetum and microspore of stage 9 anthers,which was consistent with developmental stages of defective phenotypes observed in double mutant.The expression of genes essential for tapetum development,ClATM1,ClAMS,ClMS1 and ClMS188,was decreased in Clbbm/Clplt2 double mutants.Moreover,the transcriptome analysis indicated that ClBBM and ClPLT2 participated in tapetum and pollen wall development by regulate cell cycle,transmembrane transport,glucan and cellulose metabolic process.Collectively,ClBBM and ClPLT2 were functionally redundant in regulating gametophyte development in watermelon,and their functions differ from their homologous genes in model plant Arabidopsis.
基金financed by the National Natural Science Foundation of China(31471894)the China Agriculture Research System of MOF and MARA(CARS-25)the Agricultural Science and Technology Innovation Program of Chinese Academy of Agricultural Sciences(CAASASTIP-ZFRI)。
文摘Watermelon(Citrullus lanatus)is an economically important horticultural crop.However,it is susceptible to lowtemperature stress,which significantly challenges its production and supply.Despite the great economic importance of watermelon,little is known about its response to low-temperature stress at the transcriptional level.In this study,we performed a time-course transcriptome analysis to systematically investigate the regulatory network of watermelon under low-temperature stress.Six low-temperature-responsive gene clusters representing six expression patterns were identified,revealing diverse regulation of metabolic pathways in watermelon under lowtemperature stress.Analysis of temporally specific differentially expressed genes revealed the time-dependent nature of the watermelon response to low temperature.Moreover,ClMYB14 was found to be a negative regulator of low-temperature tolerance as ClMYB14-OE lines were more susceptible to low-temperature stress.Co-expression network analysis demonstrated that ClMYB14 participates in the low-temperature response by regulating the unsaturated fatty acid pathway and heat shock transcription factor.This study provides substantial information for understanding the regulatory network of watermelon in response to low-temperature stress,and identifies candidate genes for the genetic improvement of watermelon with higher low-temperature tolerance.
基金supported by grants from theKey Scientific and Technological Project of Henan Province,China(222102110124)the Joint Fund of Science and Technology Research and Development Plan,Henan Province,China(222103810009)+4 种基金the National Natural Science Foundation of China(32172574,3217180560)the Funding of Joint Research on Agricultural Varieties Improvement of Henan Province,China(2022010503)the Major Science and Technology Project of Henan Province,China(221100110400)the Natural Science Foundation of Henan,China(222300420050)the Science and Technology Innovation Talent Support Program of Henan Province,China(23HASTIT034).
文摘The color and pattern of watermelon rind are crucial external traits that directly affect consumer preferences.Watermelons with stripes having a stronger color than the background rind are ideal for studying stripe patterns in plants,while there is still limited knowledge about the genetic mechanisms underlying stripe coloration due to the lack of germplasm resources.In this study,we focused on a watermelon germplasm with colorless stripes,and genetic analysis revealed that the trait is controlled by a single recessive gene.The gene Clsc(Citrullus lanatus stripe coloration),which is responsible for the colorless stripe,was localized into a 147.6 kb region on Chr9 by linkage analysis in a large F2 mapping population.Further analysis revealed that the Cla97C09G175170 gene encodes the APRR2 transcription factor,plays a crucial role in determining the watermelon colorless stripe phenotype and was deduced to be related to chlorophyll synthesis and chloroplast development.Physiological experiments indicated that Cla97C09G175170 may significantly influence chloroplast development and chlorophyll synthesis in watermelon.The results of this study provide a better understanding of the molecular mechanism of stripe coloration in watermelon and can be useful in the development of marker-assisted selection(MAS)for new watermelon cultivars.
基金supported by Shaanxi Provincial Central Leading Local Science and Technology Development Special Fund(Grant No.2023ZY-QYCX-02)the National Youth Talent Program(Grant No.A279021801)+3 种基金Earmarked Fund for China Agriculture Research System(Grant No.CARS-25)Key R&D Program of Shaanxi Province(Grant Nos.2023-YBNY-008 and 2024NC-YBXM-032)the Fundamental Research Funds for the Central Universities(Grant Nos.10120221103 and 2452022111)the Science and Technology Innovation Team of Shaanxi(Grant No.2021TD-32).
文摘Watermelon(Citrullus lanatus),one of the top five fruit crops based on the gross tonnage and cultivated area globally,holds major economic importance in agriculture and contributes substantially to farmers’incomes.Watermelon cultivation relies on sexual reproduction,with meiosis playing a pivotal role in this process.However,our understanding of the meiotic mechanism in watermelon remains limited.In this study,we utilized CRISPR/Cas9 technology to target ClDYAD,a homolog of the meiosis-related genes AtDYAD and OsAM1,and conducted functional analysis to explore the initiation of meiosis in watermelon.ClDYAD was highly expressed in tender male flowers both before and during the early stages of meiosis.Mutations in ClDYAD led to meiotic arrest at the leptotene stage,impeding the normal enlargement of microspore mother cells and megasporocytes.This resulted in the absence of pollen in anthers and seed abortion.ClDYAD physically interacts with the protein encoded by Cla97C07G137480,which was identified as a switch-associated protein 70-like protein(ClSWAP-70).The expression pattern of ClSWAP-70 in tender male flowers of various sizes matched with the changes in ClDYAD mRNA levels.These findings shed light on the molecular mechanisms governing the initiation of meiosis in watermelon,offering valuable insights into male and female sterility in Cucurbitaceae plants and guiding future research.
基金Supported by Scientific Research and Development Fund of Hefei University of Technology(070602F)Research Funding Project for Young Teachers in Colleges of Anhui Province(2008JQ1009)~~
文摘[Objective] The aim of this study was to screen bacteria strains with stable antagonistic effect against watermelon fusarium wilt from soil and investigate the biological control of watermelon fusarium wilt by applying the antagonistic bacteria strains into soil.[Method] Actinomycete strains,fluorescent bacteria strains and bacillus strains were isolated from soil samples by the dilution-plate method,then its resistance was screened respectively by the improved confront culture method after colonies were purified.Finally,bacteria strains with better antagonistic effect were identified.[Result] 29 bacteria strains with stable antagonistic effect against watermelon fusarium wilt were screened from 39 soil samples,which contained 15 fluorescent bacteria strains,5 bacillus strains and 9 actinomycete strains.Furthermore,three antagonistic bacteria strains of FM2,FM3 and FM4 with the strongest antagonism were identified primarily.[Conclusion] According to cultural characteristics,morphological observation,biochemical and physiological tests,FM2 belongs to bacillus subtilis,while FM3 and FM4 belong to micrococcus.
文摘The identification of germplasm is an important step for effective utilization of the available germplasm. In previous studies, isoenzyme, RAPD and SSR techniques had been used to conduct the genetic identification of watermelon ( Citrullus lanatus (Thunb.) Mansf.), but their effectiveness was limited due to the extremely narrow genetic background among watermelon genotypes. In this research, amplified fragment length polymorphism (AFLP), which was reported as a reliable technique with high efficiency in detecting polymorphism, was used to conduct genetic analysis and variety identification of thirty genotypes of watermelon core collection that represent a wide range of breeding and commercially available germplasm. As a result, a DNA fingerprint based on 15 bands amplified with four primer combinations was developed. In this fingerprint, each genotype has its unique fingerprint pattern and can be distinguished from each other. Furthermore, in or der to facilitate the utilization of AFLP marker in practice, one specific AFLP band of genotype 'PI296341' coming from fragment amplified by primer combination E-AT/M-CAT was successfully converted into a sequence characterized amplified region (SCAR) marker.
基金Guangxi Scientific Research and Technological Development Program of China(15104001-25,1598016-13)Guangxi Natural Science Foundation of China(2014GXNSFDA118015,2016GXNSFCA380008)Special Fund for Basal Scientific Research of Guangxi Academy of Agricultural Sciences(2015YT34)~~
文摘This study was conducted to investigate the effects of interplanting of sugarcane with watermelon and soybean on agronomic traits, yields, quality and benefit of crops, so as to provide reference for extension of the interplanting mode of sugarcane with watermelon or soybean. There were 4 treatments： CK1 （sole planting of sugarcane, no fertilization）, CK2 （sole planting of sugarcane, applying chemical fertilizers）, T1 （interplanting sugarcane with watermelon, applying chemical fertilizers ＋ cow dung）, and T2 （interplanting sugarcane with soybean, applying chemical fertilizers ＋ cow dung）. The results showed that compared with CK2, the sugarcane yield of treatment T1 reached 2.5 t/hm2, the watermelon yield was 1.02 t/hm2, and the total economic benefit increased by 3090 Yuan/hm2; the sugarcane yield in treatment T2 decreased by 7.61 t/hm2 （but not significant）, and the soybean yield was 0.35 t/hm2, and the total economic benefit increased by 720 Yuan/hm2; and the total sugar content in watermelon flesh was 8.59%, and the crude protein content in soybean was 36.15%, satisfying the quality indexes of the same agricultural products. Compared with sole planting of sugarcane, sugarcane plus watermelon or soybean interplanting mode improved economic benefit, treatment T1 showed economic benefit far higher than treatment T2, and is suitable for sugarcane regions with good water and fertilizer conditions and enough labor, and the T2 mode has simple operation, and is suitable for large-area extension.
基金Supported by China Agricultural Research System(CARS-26)~~
文摘[Objective] This study investigated the spatial characteristics of counties （cities） with comparative advantages in watermelon and melon production to provide reference bases in formulating strategies for the development of watermelon and melon industries in Hainan Province. [Method] By using the sowing area, total yield, and yield per unit area of watermelon and melon in Hainan Province as research u- nits, the yield comparative advantage （YCA）, efficiency comparative advantage （E- CA）, scale comparative advantage （SCA）, concentration ratio comparative advantage （CRCA）, comprehensive comparative advantage （CCA）, ratio of yield per unit area （RYPA）, sowing area ratio （SAR）, and distribution characteristics of watermelon and melon were systematically analyzed. By referring to the agricultural statistic data of 18 counties （cities） in Hainan Province, indexes for each research unit （i.e., the YCA index, ECA index, SCA index, CRCA index, CCA index, RYPA index, and SAR index） were established and calculated to determine the comparative advantage of watermelon and melon production in Hainan Province. A spatial expression of the research result on a map was conducted by using GIS software. [Result] Seven counties （cities） exhibited comparative advantages in watermelon production, namely, Lingshui, Wanning, Wenchang, Dongfang, Sanya, Ledong, and Changjiang. The Eastern and Southern Hainan Provinces had CCAs, and the Western and Northern Hainan Provinces could be reserved for future development. For melon production, four counties （cities） exhibited comparative advantages, namely, Ledong, Lingshui, Sanya, and Dongfang. The Southern Hainan Province had CCA, whereas the West- ern Hainan Province could be reserved for later development. [Conclusion] The result has showed that establishing watermelon and melon as dominant agricultural prod- ucts is necessary for the future development of the industry and for the formulation of a layout of regions with advantages, where key support and construction should be provided preferentially with the aim to raise the yield, quality, and market com- petitiveness of products.
文摘Watermelon, as a traditional dominant crop in Beijing, has obvious indus- trial advantages. The mixed substrate soilless cultivation techniques developed by the Beijing Agricultural Technology Extension Station for mini watermelon in spring greenhouse can effectively solve the problem of continuous cropping in facility wa- termelon, and they are conducive to green, safe and efficient development of water- melon industry for fixed nutrient solution formula, automatic water and fertilizer irri- gation, stable product quality and facilitating large-scale and standardized production.
基金Supported by Earmarked Fund for China Agriculture Research System(CARS-26)Science and Technology Development Fund of Guangxi Academy of AgriculturalSciences(GNK2013YZ26)National Space Breeding Project(2006HT100113)~~
文摘[Objective]This study aimed to clarify the spatial patterns of comparative advantage of watermelon production in Guangxi Zhuang Autonomous Region, to pro-vide theoretical basis for the development of watermelon industry in China. [Method] Based on the agricultural statistics data of Guangxi and al over China, yield com-parative advantage （YCA） index, efficiency comparative advantage （ECA） index, scale comparative advantage （SCA） index, concentration ratio comparative advantage （CRCA） index, comprehensive comparative advantage （CCA） index, ratio of yield per unit area （RYPA） index and sowing area ratio （SAR） index were established and calculated to determine the watermelon production comparative advantages in 31 provinces （cities） in China. Spacial patterns of the comparative advantages were produced by using GIS software. [Result] Nine provinces Shandong, Henan, Anhui, Hebei, Hubei, Jiangsu, Hunan, Zhejiang and Guangxi were the dominant regions in watermelon production al over the country. The Central and Eastern China showed the integrated comparative advantage in watermelon production, while the Southern, Northeastern, Northern and Northwestern China can be considered as the potential places for watermelon production in future. Southwest China gave more priority to watermelon production, so the comparative advantages kept increasing here. [Con-clusion] Based on this study, watermelon production should be a prior consideration among the agricultural products in Guangxi. Related measures should be developed to optimize the regional distribution of watermelon in Guangxi and China to promote healthy competition in watermelon production.
基金Supported by Agricultral Science and Technology Development Program of Shanxi Pvince(20150311010-1)Agricultral Science and Technology Development Program of Datong City(201468-2,2015099)~~
文摘[Objective] This study was conducted to reveal the effect of exogenous calcium （Ca） in mitigating the damage caused by NaCI stress to watermelon seedlings. [Method] To the liquid medium containing 100 mmol/L NaCI, CaSO4 was added to the final concentrations of 4, 6, 10 and 14 mmol/L. The morphological and physiological indices including plant height, stem diameter, number of leaves per plant, maximum leaf length, maximum leaf width, seedling fresh weight and dry weight, malondialdehyde （MDA） content, relative permeability of plasma membrane, ascorbic acid （AsA） content, free proline content, soluble sugar content and soluble protein content in leaves of the seedlings treated with above media for 10 d were measured. [Result] NaCI stress significantly inhibited the growth of watermelon seedlings. The membrane permeability and MDA content in leaves were significantly increased under NaCI stress, and the contents of proline, soluble sugar, soluble protein and AsA were increased to different extents. Exogenous CaSO4 influenced the morphological and physiological indices of seedlings under NaCI stress in a manner. Treated with 6 mmol/L CaSO4, the growth of seedlings under salinity was significantly improved; membrane permeability and MDA content were drastically reduced, the contents of proline, soluble sugar, soluble pro- tein and AsA in leaves were significantly increased. [Conclusion] Exogenous CaSO＋ alleviates lipid peroxidation and inhibition of seedling growth under NaCI stress by improving the abilities of antioxidation and osmotic adjustment, and 6 mmol/L CaSO4 showed the best effect.
