Leaf is a vital organ of plants that plays an essential role in photosynthesis and respiration.As an important agronomic trait in leaf development,leaf shape is classified into lobed,entire(no-lobed),and serrated in m...Leaf is a vital organ of plants that plays an essential role in photosynthesis and respiration.As an important agronomic trait in leaf development,leaf shape is classified into lobed,entire(no-lobed),and serrated in most crops.In this study,two-lobed leaf watermelon inbred lines WT2 and WCZ,and a no-lobed leaf watermelon inbred line WT20 were used to create two F_(2)populations.Segregation analysis suggested that lobed leaves were dominant over the no-lobed leaves,and it was controlled by a signal gene.A locus on watermelon chromosome 4 controlling watermelon lobed/no-lobed leaves was identified through BSA-seq strategy combined with linkage analysis.The candidate gene was fine-mapped to a 61.5 kb region between 21,224,481 and 21,285,957 bp on watermelon chromosome 4 using two F_(2)populations.Four functional genes were annotated in the candidate region,while sequences blast showed that there was a single-base deletion(A/-)only in the exon of Cla018360,which resulted in premature termination of translation in the no-lobed leaf lines.Function prediction showed that Cla018360 encodes an HD-Zip protein that has been reported to regulate the development of leaf shape.The single-base deletion also occurred in the HD-Zip domain.We inferred that the Cla018360 gene is the candidate gene for regulating the development of lobed/no-lobed leaves in watermelon.Gene expression analysis showed that Cla018360 was highly expressed in young leaves.Phylogenetic analysis showed that Cla018360 had a close genetic relationship with AtHB51,which had been reported to regulate the formation of leaf shape in Arabidopsis.Furthermore,transcriptome analysis showed that a total of 333 differentially expressed genes were identified between WT2 and WT20,of which 115 and 218 genes were upregulated and downregulated in no-lobed leaved watermelon WT20.This study not only provides a good entry point for studying leaf development but also provides foundational insights into breeding for special plant architecture in watermelon.展开更多
[Objectives]This study was conducted to explore how to improve the waterlogging tolerance of red-seed watermelon through grafting,to provide a theoretical basis for its cultivation in rainy season.[Methods]The effects...[Objectives]This study was conducted to explore how to improve the waterlogging tolerance of red-seed watermelon through grafting,to provide a theoretical basis for its cultivation in rainy season.[Methods]The effects of flooding stress on the growth and root physiological and biochemical characteristics of grafted and own-rooted red-seed watermelon seedlings were studied using Luffa as rootstocks and"Zhongxin 1"red-seed watermelon as scions.[Results]After flooding stress,the biomass and root activity of grafted seedlings of red-seed watermelon were significantly higher than those of own-rooted seedlings.With the prolongation of flooding stress time,the soluble sugar and proline content showed a trend of first increasing and then decreasing,and the grafted seedlings had a larger increase and a smaller decrease,and were always significantly higher than own-rooted seedlings in the same period.The content of malondialdehyde in the root system of grafted seedlings increased first and then decreased,while it continued to increase in own-rooted seedlings,and the increase in own-rooted seedlings was significantly greater than that in grafted seedlings during the same period.[Conclusions]Grafting on Luffa rootstocks could improve waterlogging tolerance of red-seed watermelon.展开更多
The nuclear factor Y(NF-Y) gene family is a class of transcription factors that are widely distributed in eukaryotes and are involved in various biological processes. However, the NF-Y gene family members in watermelo...The nuclear factor Y(NF-Y) gene family is a class of transcription factors that are widely distributed in eukaryotes and are involved in various biological processes. However, the NF-Y gene family members in watermelon, a valued and nutritious fruit, remain largely unknown and their functions have not been characterized. In the present study, 22 ClNF-Y genes in watermelon, 29 CsNF-Y genes in cucumber, and 24CmNF-Y genes in melon were identified based on the whole-genome investigation and their protein properties, gene location, gene structure, motif composition, conserved domain, and evolutionary relationship were investigated. ClNF-YB9 from watermelon and its homologs in cucumber and melon were expressed specifically in seeds. Its expression remained low in the early stages of watermelon seed development,increased at 20 days after pollination(DAP), and peaked at 45–50 DAP. Moreover, the knockout mutant Clnf-yb9 exhibited abnormal leafy cotyledon phenotype, implying its critical role during seed formation.Finally, protein interaction assays showed that ClNF-YB9 interacts with all ClNF-YCs and the ClNF-YB9-YC4 heterodimer was able to recruit a ClNF-YA7 subunit to assemble a complete NF-Y complex, which may function in seed development. This study revealed the structure and evolutionary relationships of the NF-Y gene family in Cucurbitaceae and the novel function of ClNF-YB9 in regulating seed development in watermelon.展开更多
This paper expounded the current situation and genetic mechanisms of short-vine watermelon breeding from the aspects of material sources,breeding process and genetic characteristics of F_1,hoping to provide a theoreti...This paper expounded the current situation and genetic mechanisms of short-vine watermelon breeding from the aspects of material sources,breeding process and genetic characteristics of F_1,hoping to provide a theoretical basis for short-vine watermelon breeding,and breeding materials for watermelon planting innovation,as well as new opportunities for high-quality and high-yield watermelon.展开更多
[Objectives]This study was conducted to select small seedless watermelon varieties with excellent quality and high yield suitable for planting in Beijing.[Methods]Under the conditions of facility cultivation in Beijin...[Objectives]This study was conducted to select small seedless watermelon varieties with excellent quality and high yield suitable for planting in Beijing.[Methods]Under the conditions of facility cultivation in Beijing,a screening test was conducted on seven small seedless watermelon varieties for growth process,field traits,yield traits,fruit quality,and disease resistance.[Results]Varieties Mitong,Motong and Tianbao Xiaowuzi had a short growth period and relatively stable growth,and bore fruit easily,and their female flowers were closely spaced.Their yields exceeded 60000 kg/hm~2,ranking in the top three among all varieties.The fruit had a thin skin,a bright red flesh color,and a high mass fraction of soluble solids in the center.The flesh was tight or crispy,and tasted good.They also showed good disease resistance.Overall,they showed excellent comprehensive agronomic traits,and are thus suitable for facility cultivation in Beijing and its surrounding areas.[Conclusions]This study provides a theoretical basis for the upgrading of varieties and the increase in production and farmers'income in the suburbs of Beijing.展开更多
[Objectives]This study was conducted to provide a reliable theoretical basis for the correct formulation of breeding programs for red-seed watermelon and the effective breeding of hybrid offspring.[Methods]With local ...[Objectives]This study was conducted to provide a reliable theoretical basis for the correct formulation of breeding programs for red-seed watermelon and the effective breeding of hybrid offspring.[Methods]With local varieties and inbred lines of red-seed watermelon as test materials,the generalized heritability of fruit number per plant,single-fruit weight,single-fruit seed number,single-fruit seed weight,seed kernel weight,1000-seed weight,kernel-producing ratio,seed production ratio and seed volume were estimated by variance analysis;and the heritability,genetic variation coefficients,and correlation of the nine yield traits in 43 red-seed watermelon varieties were studied.[Results]The generalized heritability of fruit number per plant,single-fruit weight,single-fruit seed number,single-fruit seed weight,seed kernel weight,1000-seed weight,kernel-producing ratio,seed production ratio and seed volume were 12.86%,80.14%,75.96%,74.39%,48.01%,17.12%,24.97%,18.60%,and 37.07%,respectively.The heritability of single-fruit weight,single-fruit seed number and single-fruit seed weight was higher,and early-generation individual selection could achieve a better effect on them;and 1000-seed weight and kernel-producing ratio had a higher coefficient of genetic variation,indicating a high selection potential.[Conclusions]Indirect selection could be achieved for traits such as the single-fruit seed number,single-fruit seed weight,seed kernel weight,and seed volume by selecting the single-fruit weight.In the process of red-seed watermelon breeding,traits with high heritability can be selected in early generations of hybrids,thus playing the role of early-generation orientation.展开更多
[Objectives]This study was conducted to select suitable medium-sized watermelon varieties for early spring cultivation in Beijing.[Methods]Seven watermelon varieties were collected,including Beinong Tianjiao 2,Beinong...[Objectives]This study was conducted to select suitable medium-sized watermelon varieties for early spring cultivation in Beijing.[Methods]Seven watermelon varieties were collected,including Beinong Tianjiao 2,Beinong Tianjiao,Hongfuji,Yongfeng 1,Beinong Futian,Beinong Shijia,and Beinong Jinxiu,and Jingxin 2 was used as the control check(CK).The growth period,morphological traits,yield traits and fruit quality of the tested varieties were investigated.[Results]Beinong Tianjiao 2 had an earlier maturation stage,a fruit development period of 38 d and a total growth period of 118 d.It showed stable growth,with a single fruit weight of 7.56 kg,a fruit setting rate of 0.99 per plant,and a yield of 83076.9 kg/hm~2,which ranked,respectively,second,first,and second among all tested varieties,and were significantly superior to the CK.Furthermore,this variety had thin and tough peel,a bright red flesh color,high central sugar content,loose and crisp flesh,and a good taste.[Conclusions]It is preliminarily believed that it is suitable for early spring watermelon production in Beijing area.展开更多
[Objectives]The paper was to explore the effects of different concentrations of paclobutrazol on seedling quality of small seedless watermelon in autumn.[Methods]The leaves of watermelon seedlings were sprayed with 30...[Objectives]The paper was to explore the effects of different concentrations of paclobutrazol on seedling quality of small seedless watermelon in autumn.[Methods]The leaves of watermelon seedlings were sprayed with 30,50,80 and 120 mg/L paclobutrazol at cotyledon expansion stage,and those sprayed with tap water were used as control.[Results]All the treatments of paclobutrazol effectively inhibited the excessive growth of watermelon at seedling stage,significantly enhanced the leaf quality of watermelon seedlings and promoted root growth.The seedlings treated by 50 mg/L paclobutrazol had the best performance compared with the control:a decrease of hypocotyl by 37.9%,an increase of plant dry weight by 46.55%,significantly increased seedling strength index,deep green leaf color,thick leaves,an increase of specific leaf weight by 28.13%,and significantly heavier root weight and longer length.[Conclusions]The results will provide a reference for strong seedling cultivation of small seedless watermelon.展开更多
Climate change and variability, has embarked societies in Zanzibar to rely on horticulture (i.e. watermelon production) as an adaptive measure due to an unpromising situation of commonly used agricultural yields. Curr...Climate change and variability, has embarked societies in Zanzibar to rely on horticulture (i.e. watermelon production) as an adaptive measure due to an unpromising situation of commonly used agricultural yields. Currently, there is either no or scant information that describes the influence of climate changes and variability to watermelon production in Zanzibar. Thus, this study aimed to determine the influence of climate variability on the quantity of watermelon production in Zanzibar. The study used both primary and secondary datasets, which include the anecdotal information collected from interviewers’ responses from four districts of Unguja and Pemba, and climate parameters (rainfall, maximum and minimum temperature (Tmax and Tmin) acquired from Tanzania Meteorological Authority (TMA) at Zanzibar offices. Pearson correlation was used for analyzing the association between watermelon production and climate parameters, while paired t-test was applied to show the significance of the mean differences of watermelon and climate parameters for two periods of 2014-2017 and 2018-2021, respectively. Percentage changes were used to feature the extent to which the two investigated parameters affect each other. The anecdotal responses were sorted, calculated in monthly and seasonal averages, plotted and then analyzed. Results have shown a strong correlation (r = 0.8 at p ≤ 0.02, and r = 0.7) between watermelon production, Tmax and rainfall during OND, especially in Unguja, as well as Tmin during JJA (i.e. r = - 0.8 at p ≤ 0.02) in Pemba. Besides, results have shown the existence of significant differences between the means of watermelon production and climate parameter for the two stated periods, indicating that the climate parameters highly affects the watermelon production by either enhancing or declining the yields by 69% - 162% and 17% - 77%, respectively. Moreover, results have shown that respondents were aware that excess temperature intensity during dry periods can lead to high production costs due number of soil and other environmental factors. Besides the results have shown that OND seasonal rainfall and MAM Tmax had good association with watermelon production in Unguja while JJA Tmin declined the production in Pemba. Thus, the study concludes that seasonal variability of climate parameter has a significant influence on the watermelon production. The study calls for more studies on factors affecting watermelon production (e.g. soil characteristics, pest sides and manure), and recommends for climate based decision making on rain fed agricultural yields and routine monitoring of weather information.展开更多
Watermelon fruit undergoes distinct development stages with dramatic changes during fruit ripening.To date,the molecular mechanics of watermelon ripening remain unclear.Genetic and transcriptome evidences suggested th...Watermelon fruit undergoes distinct development stages with dramatic changes during fruit ripening.To date,the molecular mechanics of watermelon ripening remain unclear.Genetic and transcriptome evidences suggested that the ethylene response factor(ERF)gene ClERF069 may be an important candidate factor affecting watermelon fruit ripening.To dissect the roles of ClERF069 in fruit ripening,structure and phylogenetic analysis were performed using the amplified full-length sequence.Normal-ripening watermelon 97103,non-ripening watermelon PI296341-FR and the RIL population were used to analyze ClERF069 expression dynamics and the correlation with fruit ripening indexs.The results indicated that ClERF069 belongs to ERF family group VI and show high homology(83%identity)to melon ERF069-like protein.ClERF069 expression in watermelon flesh was negatively correlated with fruit lycopene content and sugar content during fruit ripening progress.Further transgenic evidences indicated that overexpression of 35S:ClERF069 in tomato noticeably delayed the ripening process up to 5.2 days.Lycopene,β-carotenoid accumulation patterns were altered and ethylene production patterns in transgenic fruits was significantly delayed during fruit ripening.Taken together,watermelon ethylene response factor ClERF069 was concluded to be a negative regulator of fruit ripening.展开更多
Fifteen expressed sequence tag (EST)-derived simple sequence repeats (EST-SSRs) were used to investigate genetic diversity in 139 plants obtained from seeds of 35 watermelon accessions collected from all the geographi...Fifteen expressed sequence tag (EST)-derived simple sequence repeats (EST-SSRs) were used to investigate genetic diversity in 139 plants obtained from seeds of 35 watermelon accessions collected from all the geographical provinces of Zimbabwe. In addition, 15 plants representing three commercial varieties developed in the United States (USA) were analyzed for comparison. A total of 65 alleles were detected among all the watermelon accessions. For the 13 polymorphic EST-SSR loci, number of alleles per locus varied from 2 to 13, with an average of 5 alleles per locus. Values for the polymorphic information content increased as the number of alleles increased, and varied from 0.15 to 0.77 with an average of 0.54 suggesting sufficient discriminatory power. Both cluster analysis and principal coordinate analysis (PCA) produced two major clusters;one with the 22 cow-melon accessions and the other with the 16 sweet watermelon accessions. Within the sweet watermelon group, two distinct sub-clusters formed, one of which contained only two of the commercial varieties from USA. Partitioning of genetic variation in the Zimbabwean material using analysis of molecular variation (AMOVA) revealed that 64% of the total variation resides between the two major forms, i.e. sweet watermelons and cow-melons, 28% between accessions within forms and 8% within accessions. The EST-SSR markers revealed a somewhat higher diversity in sweet watermelon accessions compared to that of cow-melons. This finding is contrary to previous reports using other markers (genomic SSR loci or RAPD) and/or a plant material that is likely to have experienced more stringent selection procedures compared to the landraces analyzed in our study.展开更多
As a special form of allelopathy,autotoxicity is common in cucurbits,and it is one of main factors inducing continuous cropping obstacles.Therefore,the autotoxicity research has both theoretical and practical signific...As a special form of allelopathy,autotoxicity is common in cucurbits,and it is one of main factors inducing continuous cropping obstacles.Therefore,the autotoxicity research has both theoretical and practical significance on overcoming continuous cropping obstacles.In this review,commencing on the concept of autotoxicity,research results of autotoxicity in watermelon in recent years were summarized.The significance of researches on autotoxicity in watermelon,watermelon root exudate and its autotoxicity,and the autotoxicity of watermelon stubble and the mechanisms were explained.Meanwhile,some questions needed to be further studied.展开更多
In vitro gynogenesis is an important tool used in haploid or homozygous double-haploid plant breeding.However,because of low repeatability,embryoid induction rate and quality,the molecular mechanisms remain poorly und...In vitro gynogenesis is an important tool used in haploid or homozygous double-haploid plant breeding.However,because of low repeatability,embryoid induction rate and quality,the molecular mechanisms remain poorly understood.Heat shock treatment can promote the transformation of the gametophytic pathway into the sporophyte pathway,which induces the occurrence of haploid.In this study,unfertilized ovaries were heat shocked for 0 h(A0)before flowering and for 0 h(A1),4 h(A3),8 h(A5),12 h(A7),and 24 h(A8),respectively,at 37℃at the first day of the flowering stage.The ovule enlargement rate was increased from 0%at 25℃to 96.8%at 37℃(24 h treatment).Thus,we aimed to investigate the gene expression patterns in unfertilized ovules of watermelon after different periods of heat shock by using RNA-Seq technology.The results showed that compared with A3,A5,A7,and A8,the biosynthesis of amino acid,glycine,serine and threonine metabolic pathways in A1 has changed significantly.This indicated that heat shock treatment affected the synthesis and transformation of amino acids during ovule expansion.The transcriptome data suggested gene expressions of ovule growth were significantly changed by heat-specific influences.The results provide new information on the complex relationship between in vitro gynogenesis and temperature.This provides a basis for further study of the mechanism of heat shock affecting the expansion of watermelon ovule.展开更多
In 2010, a foliar and stem-lesion disease that produced moderate to severe defoliation of watermelon was observed in the southern Great Plains. The disease was ultimately determined to be caused by Myrothecium roridum...In 2010, a foliar and stem-lesion disease that produced moderate to severe defoliation of watermelon was observed in the southern Great Plains. The disease was ultimately determined to be caused by Myrothecium roridum. The objective of this study was to compare the susceptibility of the vegetation and fruit of a broad range of commercially important cucurbits to three isolates obtained from these foliar lesions on watermelon. In greenhouse foliar inoculation experiments, cantaloupe, honeydew, cucumber, squash, and watermelon were susceptible to the fungus with cantaloupe and honeydew being the most susceptible and watermelon the most resistant. Furthermore, greenhouse inoculations supported earlier field observations as differential resistance was exhibited among the watermelon cultivars as well as the cucurbit types. All tested cucurbit fruit exhibited interior lesions when inoculated sub-epidermally with M. roridum isolates. However, natural infection of watermelon and pumpkin fruit has never been reported.展开更多
This study was designed to bridge gap in nutritionally skewed available biscuits and the high volume of agricultural waste generated by investigating the quality of biscuits prepared from wheat base, supplemented with...This study was designed to bridge gap in nutritionally skewed available biscuits and the high volume of agricultural waste generated by investigating the quality of biscuits prepared from wheat base, supplemented with waste from watermelon rinds and orange pomace as possible nutritious alternatives. Biscuit samples were respectively produced from blends of wheat, watermelon rind and orange pomace in the following ratio 100:0:0;90:5:5;80:10:10;70:15:15 and 60:20:20, labelled samples A, B, C, D and E. F</span><span style="font-family:Verdana;">unctional, proximate, mineral and sensory properties of the formulated biscuit samples</span><span style="font-family:Verdana;"> were carried out using standard analytical procedures. The results showed that p</span><span style="font-family:Verdana;">roximate composition of samples B - E significantly increased (p < 0.05) except for carbohydrate content when compared with sample A used as control. </span><span style="font-family:Verdana;">There were also significant increases (p < 0.05) in mineral contents of supplemented samples compared to control. The result of the sensory evaluation showed that wheat flour can be substituted with watermelon rind and orange pomace flours up to 10% without adversely affecting the overall quality attributes of the biscuits. These results indicate the robustness of food value addition as an effective means of improving nutritional quality of biscuits while contributing to waste management in the agricultural value chain.展开更多
To balance the relationship between high yield and low nitrogen supply,the nitrogen utilization efficiency of watermelon needs to be improved urgently.Nodule inception-like Protein(NLP)transcription factors play a key...To balance the relationship between high yield and low nitrogen supply,the nitrogen utilization efficiency of watermelon needs to be improved urgently.Nodule inception-like Protein(NLP)transcription factors play a key node role in nitrate response and growth and development of plant,however,comprehensive analysis of the NLP gene family in watermelon is unclear.This study explored the functional classification,evolutionary characteristics,and expression profile of the ClNLP gene family.Three ClNLPs were categorized into three groups according to their gene structure and phylogeny.All of them contained the conserved RWP-RK and PB1 domains.Evolutionary analysis of ClNLPs revealed that ClNLP1 and ClNLP3 underwent strong purified selection.In addition,cis-acting elements related to plant hormones and abiotic stresses were present in the ClNLP promoter.According to tissue-specific analysis ClNLP was widely expressed in roots,stems,leaves,flowers and fruits,and ClNLP1 was significantly induced in the roots of different nitrogen utilization varieties under different nitrate nitrogen supply.The SRTING functional protein association network suggested that ClNLP1 is associated with most genes,such as NRT1.1,NRT2.1,NIA1,and NIR1,and the dual-luciferase reporter assay found that ClNLP1 positively regulates the expression of ClNRT2.1.We speculated that ClNLP1 might play a central role in regulating the response of watermelon to nitrate nitrogen.展开更多
Watermelon(Citrullus lanatus)is one of the world’s most important fruit crops,and China produces the most watermelons in the world.Recently,a watermelon variome consisting of 414 key resequenced accessions was report...Watermelon(Citrullus lanatus)is one of the world’s most important fruit crops,and China produces the most watermelons in the world.Recently,a watermelon variome consisting of 414 key resequenced accessions was reported.However,the genetic relationships and pedigree of Chinese watermelon varieties in the seed market remain unclear.In this study,241 evenly distributed perfect single nucleotide polymorphisms(SNPs)derived from the watermelon variome were selected for variety identification.The diversity of 247 Chinese watermelon varieties was identified based on their SNP genotypes.The 247 watermelon varieties were clustered into five subpopulations:the East Asian ecotype,intermediate ecotype,small fruit with red flesh ecotype,small fruit with yellow flesh ecotype,and American ecotype.We further established the pedigree of four subpopulations,of which JingXinNo.1,ZaoChunHongYu,HuangXiaoYu and XiaoLan,and Sugarlee were the main doner of the East Asian ecotype,small fruit with red flesh ecotype,small fruit with yellow flesh ecotype,and American ecotype,respectively.Thirty-two core SNPs were selected and applied in watermelon variety identification.They were also validated by the Kompetitive allele-specific PCR(KASPar)platform.The present study furthered our understanding of the genetic relationships and pedigree of watermelon varieties in China,and will help to manage the plant variety protection in watermelon.展开更多
Proline accumulation has been shown to occur in plants in response to various environmental stresses.Although proline metabolismrelated genes have been functionally characterized,the inter-organ transport of proline i...Proline accumulation has been shown to occur in plants in response to various environmental stresses.Although proline metabolismrelated genes have been functionally characterized,the inter-organ transport of proline in stressed plants remains unclear.In this study,free proline was detected with significant accumulations in the roots,stems,and leaves of watermelon drought-tolerant germplasm M08 and drought-susceptible line Y34 under drought stress.Expression profiling and enzyme activity measurements revealed that ClP5CS1 gene,rather than its paralog ClP5CS2,mainly contributes to the proline synthesis in leaves via the Glu pathway.Additionally,over-expression of the ClP5CS genes significantly enhanced the drought tolerance of transgenic Arabidopsis lines.Furthermore,we confirmed that proline is mainly synthesized in leaves and transported to roots in watermelon under drought stress.Transcriptome and expression analyses revealed that the genes involved in proline metabolism exhibited different expression levels.Specifically,ClP5CS1 was upregulated in leaves and roots,while ClP5CS2 was downregulated under drought stress.Also,415 and 362 differently expressed TFs were identified in roots and leaves,respectively,with the majority upregulated in the former.Ultimately,a model for proline metabolism was proposed.The findings of this study provided new insights into the biosynthesis,transport,and regulatory mechanism of drought-induced proline in plants.展开更多
Carotenoids are responsible for the different flesh colors in watermelon fruit, such as white, salmon yellow, orange, pale yellow, canary yellow, crimson red, and scarlet red. In red-fleshed watermelons lycopene const...Carotenoids are responsible for the different flesh colors in watermelon fruit, such as white, salmon yellow, orange, pale yellow, canary yellow, crimson red, and scarlet red. In red-fleshed watermelons lycopene constitutes the major pigment and b-carotene the secondary. The predominant carotenoid in yellow-fleshed watermelon is neoxanthin. Lycopene content in watermelon is related to genotype and ploidy level, harvest maturity, and growth and development conditions. Watermelon flesh colors are controlled by several gene loci. There are two or three alleles identified at each gene locus. Up to now several full-length cDNAs or gene fragments encoding enzymes in the carotenoid metabolic pathway have been isolated and characterized from mature watermelon fruits. Differential expression of carotenogenic genes was examined in flesh, ovary, leaf, and root tissues across different colored fleshes (white, canary yellow, salmon yellow, orange, and red). Carotenogenic gene expression was also analyzed at three fruit developmental stages (10, 20, and 30 days postanthesis) in five flesh colors of watermelon cultivars (red, pink, orange, yellow, and white).展开更多
Two field experiments were carried out at Akure (7oN, 5o101E) in the rainforest zone of Nigeria in 2006 and 2007 to determine the effectiveness of neem leaf, woodash and modified neem leaf extracts as fertilizer sourc...Two field experiments were carried out at Akure (7oN, 5o101E) in the rainforest zone of Nigeria in 2006 and 2007 to determine the effectiveness of neem leaf, woodash and modified neem leaf extracts as fertilizer sources in improving soil fertility, growth and yield of maize (Zea mays L) and watermelon (Citrulus lanatus) sole and intercrop. There were six treatments namely, poultry manure, neem leaf extract (sole), woodash extract, modified neem leaf (neem leaf + woodash), NPK 15-15-15 and a control (no fertilizer nor extract), replicated three times and arranged in a randomized complete block design (RCB). The extracts (neem leaf, wood ash and modified neem leaf) were applied at 1200 litres per hectare each, NPK 15-15-15 at 300 kg/ha and poultry was applied at 6t/ha. The results showed that there were significant increases (P 2O), K, Ca, Mg, Na, O.M, P and N compared to NPK 15-15-15 and neem leaf extract. For instance, modified neem leaf extract increased soil pH (H2O), K, Ca, Mg, Na, O.M, P and N by 12.4%, 32.8%, 25%, 23.7%, 19.32%, 17.24% and 20% respectively compared to neem leaf extract under intercrop plot. The high soil K/Ca, K/Mg and P/Mg ratios in the NPK 15-15-15 fertilizer treatment led to an imbalance in the supply of P, K, Ca and Mg nutrients to maize and watermelon crops. The least values for growth, yield and soil parameters were recorded under the control treatment. In these experiments, modified neem leaf extract (woodash + neem leaf extracts) applied at 1200 litres/ha was the most effective in improving soil fertility, growth and yield of maize and watermelon (sole and intercrop) and could substitute for 6 tons per hectare of poultry manure and 300kg/ha of NPK 15-15-15 fertilizer.展开更多
基金This research was supported by the National Natural Science Foundation of China(32102389,32172602)the Zhongyuan Youth Talent Support Program(ZYQR201912161)+3 种基金the Program for Science&Technology Innovation Talents in Universities of Henan Province(21HASTIT038)the Funding of Joint Research on Agricultural Varietie Improvement of Henan Province(2022010503)the Major Science and Technology Project of Henan Province(221100110400)the Science and Technology Innovation Fund of Henan Agricultural University(KJCX2021A14).
文摘Leaf is a vital organ of plants that plays an essential role in photosynthesis and respiration.As an important agronomic trait in leaf development,leaf shape is classified into lobed,entire(no-lobed),and serrated in most crops.In this study,two-lobed leaf watermelon inbred lines WT2 and WCZ,and a no-lobed leaf watermelon inbred line WT20 were used to create two F_(2)populations.Segregation analysis suggested that lobed leaves were dominant over the no-lobed leaves,and it was controlled by a signal gene.A locus on watermelon chromosome 4 controlling watermelon lobed/no-lobed leaves was identified through BSA-seq strategy combined with linkage analysis.The candidate gene was fine-mapped to a 61.5 kb region between 21,224,481 and 21,285,957 bp on watermelon chromosome 4 using two F_(2)populations.Four functional genes were annotated in the candidate region,while sequences blast showed that there was a single-base deletion(A/-)only in the exon of Cla018360,which resulted in premature termination of translation in the no-lobed leaf lines.Function prediction showed that Cla018360 encodes an HD-Zip protein that has been reported to regulate the development of leaf shape.The single-base deletion also occurred in the HD-Zip domain.We inferred that the Cla018360 gene is the candidate gene for regulating the development of lobed/no-lobed leaves in watermelon.Gene expression analysis showed that Cla018360 was highly expressed in young leaves.Phylogenetic analysis showed that Cla018360 had a close genetic relationship with AtHB51,which had been reported to regulate the formation of leaf shape in Arabidopsis.Furthermore,transcriptome analysis showed that a total of 333 differentially expressed genes were identified between WT2 and WT20,of which 115 and 218 genes were upregulated and downregulated in no-lobed leaved watermelon WT20.This study not only provides a good entry point for studying leaf development but also provides foundational insights into breeding for special plant architecture in watermelon.
基金Supported by"Watermelon and Muskmelon Germplasm Innovation and Genetic Improvement"Post of Guangxi Bagui Scholars(2016A11)。
文摘[Objectives]This study was conducted to explore how to improve the waterlogging tolerance of red-seed watermelon through grafting,to provide a theoretical basis for its cultivation in rainy season.[Methods]The effects of flooding stress on the growth and root physiological and biochemical characteristics of grafted and own-rooted red-seed watermelon seedlings were studied using Luffa as rootstocks and"Zhongxin 1"red-seed watermelon as scions.[Results]After flooding stress,the biomass and root activity of grafted seedlings of red-seed watermelon were significantly higher than those of own-rooted seedlings.With the prolongation of flooding stress time,the soluble sugar and proline content showed a trend of first increasing and then decreasing,and the grafted seedlings had a larger increase and a smaller decrease,and were always significantly higher than own-rooted seedlings in the same period.The content of malondialdehyde in the root system of grafted seedlings increased first and then decreased,while it continued to increase in own-rooted seedlings,and the increase in own-rooted seedlings was significantly greater than that in grafted seedlings during the same period.[Conclusions]Grafting on Luffa rootstocks could improve waterlogging tolerance of red-seed watermelon.
基金supported by the National Youth Talent Program (A279021801)Key-Area R&D Program of Guangdong province (2022B0202060001)+4 种基金Key R&D Program of Shaanxi Province (2023-YBNY-008)the Science and Technology Innovation Team of Shaanxi (2021TD-32)the Natural Science Foundation of Shaanxi Province (2021JM-089, 2022JM-112 and 2022JQ-162)the Key R&D Project from Yangling Seed Industry Innovation Center (K3031322016)the Fundamental Research Fund from Northwest A&F University (2452022111)。
文摘The nuclear factor Y(NF-Y) gene family is a class of transcription factors that are widely distributed in eukaryotes and are involved in various biological processes. However, the NF-Y gene family members in watermelon, a valued and nutritious fruit, remain largely unknown and their functions have not been characterized. In the present study, 22 ClNF-Y genes in watermelon, 29 CsNF-Y genes in cucumber, and 24CmNF-Y genes in melon were identified based on the whole-genome investigation and their protein properties, gene location, gene structure, motif composition, conserved domain, and evolutionary relationship were investigated. ClNF-YB9 from watermelon and its homologs in cucumber and melon were expressed specifically in seeds. Its expression remained low in the early stages of watermelon seed development,increased at 20 days after pollination(DAP), and peaked at 45–50 DAP. Moreover, the knockout mutant Clnf-yb9 exhibited abnormal leafy cotyledon phenotype, implying its critical role during seed formation.Finally, protein interaction assays showed that ClNF-YB9 interacts with all ClNF-YCs and the ClNF-YB9-YC4 heterodimer was able to recruit a ClNF-YA7 subunit to assemble a complete NF-Y complex, which may function in seed development. This study revealed the structure and evolutionary relationships of the NF-Y gene family in Cucurbitaceae and the novel function of ClNF-YB9 in regulating seed development in watermelon.
文摘This paper expounded the current situation and genetic mechanisms of short-vine watermelon breeding from the aspects of material sources,breeding process and genetic characteristics of F_1,hoping to provide a theoretical basis for short-vine watermelon breeding,and breeding materials for watermelon planting innovation,as well as new opportunities for high-quality and high-yield watermelon.
基金Supported by Special Crop Innovation Team of Beijing(BAIC04-2022)。
文摘[Objectives]This study was conducted to select small seedless watermelon varieties with excellent quality and high yield suitable for planting in Beijing.[Methods]Under the conditions of facility cultivation in Beijing,a screening test was conducted on seven small seedless watermelon varieties for growth process,field traits,yield traits,fruit quality,and disease resistance.[Results]Varieties Mitong,Motong and Tianbao Xiaowuzi had a short growth period and relatively stable growth,and bore fruit easily,and their female flowers were closely spaced.Their yields exceeded 60000 kg/hm~2,ranking in the top three among all varieties.The fruit had a thin skin,a bright red flesh color,and a high mass fraction of soluble solids in the center.The flesh was tight or crispy,and tasted good.They also showed good disease resistance.Overall,they showed excellent comprehensive agronomic traits,and are thus suitable for facility cultivation in Beijing and its surrounding areas.[Conclusions]This study provides a theoretical basis for the upgrading of varieties and the increase in production and farmers'income in the suburbs of Beijing.
基金Supported by"Watermelon and Muskmelon Germplasm Innovation and Genetic Improvement"Post of Guangxi Bagui Scholars(2016A11)。
文摘[Objectives]This study was conducted to provide a reliable theoretical basis for the correct formulation of breeding programs for red-seed watermelon and the effective breeding of hybrid offspring.[Methods]With local varieties and inbred lines of red-seed watermelon as test materials,the generalized heritability of fruit number per plant,single-fruit weight,single-fruit seed number,single-fruit seed weight,seed kernel weight,1000-seed weight,kernel-producing ratio,seed production ratio and seed volume were estimated by variance analysis;and the heritability,genetic variation coefficients,and correlation of the nine yield traits in 43 red-seed watermelon varieties were studied.[Results]The generalized heritability of fruit number per plant,single-fruit weight,single-fruit seed number,single-fruit seed weight,seed kernel weight,1000-seed weight,kernel-producing ratio,seed production ratio and seed volume were 12.86%,80.14%,75.96%,74.39%,48.01%,17.12%,24.97%,18.60%,and 37.07%,respectively.The heritability of single-fruit weight,single-fruit seed number and single-fruit seed weight was higher,and early-generation individual selection could achieve a better effect on them;and 1000-seed weight and kernel-producing ratio had a higher coefficient of genetic variation,indicating a high selection potential.[Conclusions]Indirect selection could be achieved for traits such as the single-fruit seed number,single-fruit seed weight,seed kernel weight,and seed volume by selecting the single-fruit weight.In the process of red-seed watermelon breeding,traits with high heritability can be selected in early generations of hybrids,thus playing the role of early-generation orientation.
文摘[Objectives]This study was conducted to select suitable medium-sized watermelon varieties for early spring cultivation in Beijing.[Methods]Seven watermelon varieties were collected,including Beinong Tianjiao 2,Beinong Tianjiao,Hongfuji,Yongfeng 1,Beinong Futian,Beinong Shijia,and Beinong Jinxiu,and Jingxin 2 was used as the control check(CK).The growth period,morphological traits,yield traits and fruit quality of the tested varieties were investigated.[Results]Beinong Tianjiao 2 had an earlier maturation stage,a fruit development period of 38 d and a total growth period of 118 d.It showed stable growth,with a single fruit weight of 7.56 kg,a fruit setting rate of 0.99 per plant,and a yield of 83076.9 kg/hm~2,which ranked,respectively,second,first,and second among all tested varieties,and were significantly superior to the CK.Furthermore,this variety had thin and tough peel,a bright red flesh color,high central sugar content,loose and crisp flesh,and a good taste.[Conclusions]It is preliminarily believed that it is suitable for early spring watermelon production in Beijing area.
基金Beijing Innovation Consortium of Special Crops Research System(BAIC04-2022).
文摘[Objectives]The paper was to explore the effects of different concentrations of paclobutrazol on seedling quality of small seedless watermelon in autumn.[Methods]The leaves of watermelon seedlings were sprayed with 30,50,80 and 120 mg/L paclobutrazol at cotyledon expansion stage,and those sprayed with tap water were used as control.[Results]All the treatments of paclobutrazol effectively inhibited the excessive growth of watermelon at seedling stage,significantly enhanced the leaf quality of watermelon seedlings and promoted root growth.The seedlings treated by 50 mg/L paclobutrazol had the best performance compared with the control:a decrease of hypocotyl by 37.9%,an increase of plant dry weight by 46.55%,significantly increased seedling strength index,deep green leaf color,thick leaves,an increase of specific leaf weight by 28.13%,and significantly heavier root weight and longer length.[Conclusions]The results will provide a reference for strong seedling cultivation of small seedless watermelon.
文摘Climate change and variability, has embarked societies in Zanzibar to rely on horticulture (i.e. watermelon production) as an adaptive measure due to an unpromising situation of commonly used agricultural yields. Currently, there is either no or scant information that describes the influence of climate changes and variability to watermelon production in Zanzibar. Thus, this study aimed to determine the influence of climate variability on the quantity of watermelon production in Zanzibar. The study used both primary and secondary datasets, which include the anecdotal information collected from interviewers’ responses from four districts of Unguja and Pemba, and climate parameters (rainfall, maximum and minimum temperature (Tmax and Tmin) acquired from Tanzania Meteorological Authority (TMA) at Zanzibar offices. Pearson correlation was used for analyzing the association between watermelon production and climate parameters, while paired t-test was applied to show the significance of the mean differences of watermelon and climate parameters for two periods of 2014-2017 and 2018-2021, respectively. Percentage changes were used to feature the extent to which the two investigated parameters affect each other. The anecdotal responses were sorted, calculated in monthly and seasonal averages, plotted and then analyzed. Results have shown a strong correlation (r = 0.8 at p ≤ 0.02, and r = 0.7) between watermelon production, Tmax and rainfall during OND, especially in Unguja, as well as Tmin during JJA (i.e. r = - 0.8 at p ≤ 0.02) in Pemba. Besides, results have shown the existence of significant differences between the means of watermelon production and climate parameter for the two stated periods, indicating that the climate parameters highly affects the watermelon production by either enhancing or declining the yields by 69% - 162% and 17% - 77%, respectively. Moreover, results have shown that respondents were aware that excess temperature intensity during dry periods can lead to high production costs due number of soil and other environmental factors. Besides the results have shown that OND seasonal rainfall and MAM Tmax had good association with watermelon production in Unguja while JJA Tmin declined the production in Pemba. Thus, the study concludes that seasonal variability of climate parameter has a significant influence on the watermelon production. The study calls for more studies on factors affecting watermelon production (e.g. soil characteristics, pest sides and manure), and recommends for climate based decision making on rain fed agricultural yields and routine monitoring of weather information.
基金This work was financially supported by the National Key R&D Program of China(Grant No.2018YFD0100703)the Beijing Municipal Science and Technology Project(Grant No.D171100007617001)+4 种基金the Beijing Academy of Agricultural and Forestry Sciences(Grant Nos.QNJJ201733,KJCX20200202)the Ministry of Agriculture and Rural Affairs of China(Grant No.CARS-25)the Beijing Scholar Program(Grant No.BSP026)Beijing Innovation Consortium of Agriculture Research System(Grant No.BAIC10-2020)the Bagui Scholar Program(Grant No.2016A11).
文摘Watermelon fruit undergoes distinct development stages with dramatic changes during fruit ripening.To date,the molecular mechanics of watermelon ripening remain unclear.Genetic and transcriptome evidences suggested that the ethylene response factor(ERF)gene ClERF069 may be an important candidate factor affecting watermelon fruit ripening.To dissect the roles of ClERF069 in fruit ripening,structure and phylogenetic analysis were performed using the amplified full-length sequence.Normal-ripening watermelon 97103,non-ripening watermelon PI296341-FR and the RIL population were used to analyze ClERF069 expression dynamics and the correlation with fruit ripening indexs.The results indicated that ClERF069 belongs to ERF family group VI and show high homology(83%identity)to melon ERF069-like protein.ClERF069 expression in watermelon flesh was negatively correlated with fruit lycopene content and sugar content during fruit ripening progress.Further transgenic evidences indicated that overexpression of 35S:ClERF069 in tomato noticeably delayed the ripening process up to 5.2 days.Lycopene,β-carotenoid accumulation patterns were altered and ethylene production patterns in transgenic fruits was significantly delayed during fruit ripening.Taken together,watermelon ethylene response factor ClERF069 was concluded to be a negative regulator of fruit ripening.
文摘Fifteen expressed sequence tag (EST)-derived simple sequence repeats (EST-SSRs) were used to investigate genetic diversity in 139 plants obtained from seeds of 35 watermelon accessions collected from all the geographical provinces of Zimbabwe. In addition, 15 plants representing three commercial varieties developed in the United States (USA) were analyzed for comparison. A total of 65 alleles were detected among all the watermelon accessions. For the 13 polymorphic EST-SSR loci, number of alleles per locus varied from 2 to 13, with an average of 5 alleles per locus. Values for the polymorphic information content increased as the number of alleles increased, and varied from 0.15 to 0.77 with an average of 0.54 suggesting sufficient discriminatory power. Both cluster analysis and principal coordinate analysis (PCA) produced two major clusters;one with the 22 cow-melon accessions and the other with the 16 sweet watermelon accessions. Within the sweet watermelon group, two distinct sub-clusters formed, one of which contained only two of the commercial varieties from USA. Partitioning of genetic variation in the Zimbabwean material using analysis of molecular variation (AMOVA) revealed that 64% of the total variation resides between the two major forms, i.e. sweet watermelons and cow-melons, 28% between accessions within forms and 8% within accessions. The EST-SSR markers revealed a somewhat higher diversity in sweet watermelon accessions compared to that of cow-melons. This finding is contrary to previous reports using other markers (genomic SSR loci or RAPD) and/or a plant material that is likely to have experienced more stringent selection procedures compared to the landraces analyzed in our study.
文摘As a special form of allelopathy,autotoxicity is common in cucurbits,and it is one of main factors inducing continuous cropping obstacles.Therefore,the autotoxicity research has both theoretical and practical significance on overcoming continuous cropping obstacles.In this review,commencing on the concept of autotoxicity,research results of autotoxicity in watermelon in recent years were summarized.The significance of researches on autotoxicity in watermelon,watermelon root exudate and its autotoxicity,and the autotoxicity of watermelon stubble and the mechanisms were explained.Meanwhile,some questions needed to be further studied.
基金supported by the earmarked fund for China Agriculture Research System (CARS-25)the Fundamental Research Funds of the Chinese Academy of Agricultural Sciences (Y2018YJ15 and Y2019XK16-03)+1 种基金the Agricultural Science and Technology Innovation Program, Chinese Academy of Agricultural Sciences (CAAS-ASTIP2018-ZFRI)the National Key R&D Program of China (2018YFD0201310)
文摘In vitro gynogenesis is an important tool used in haploid or homozygous double-haploid plant breeding.However,because of low repeatability,embryoid induction rate and quality,the molecular mechanisms remain poorly understood.Heat shock treatment can promote the transformation of the gametophytic pathway into the sporophyte pathway,which induces the occurrence of haploid.In this study,unfertilized ovaries were heat shocked for 0 h(A0)before flowering and for 0 h(A1),4 h(A3),8 h(A5),12 h(A7),and 24 h(A8),respectively,at 37℃at the first day of the flowering stage.The ovule enlargement rate was increased from 0%at 25℃to 96.8%at 37℃(24 h treatment).Thus,we aimed to investigate the gene expression patterns in unfertilized ovules of watermelon after different periods of heat shock by using RNA-Seq technology.The results showed that compared with A3,A5,A7,and A8,the biosynthesis of amino acid,glycine,serine and threonine metabolic pathways in A1 has changed significantly.This indicated that heat shock treatment affected the synthesis and transformation of amino acids during ovule expansion.The transcriptome data suggested gene expressions of ovule growth were significantly changed by heat-specific influences.The results provide new information on the complex relationship between in vitro gynogenesis and temperature.This provides a basis for further study of the mechanism of heat shock affecting the expansion of watermelon ovule.
文摘In 2010, a foliar and stem-lesion disease that produced moderate to severe defoliation of watermelon was observed in the southern Great Plains. The disease was ultimately determined to be caused by Myrothecium roridum. The objective of this study was to compare the susceptibility of the vegetation and fruit of a broad range of commercially important cucurbits to three isolates obtained from these foliar lesions on watermelon. In greenhouse foliar inoculation experiments, cantaloupe, honeydew, cucumber, squash, and watermelon were susceptible to the fungus with cantaloupe and honeydew being the most susceptible and watermelon the most resistant. Furthermore, greenhouse inoculations supported earlier field observations as differential resistance was exhibited among the watermelon cultivars as well as the cucurbit types. All tested cucurbit fruit exhibited interior lesions when inoculated sub-epidermally with M. roridum isolates. However, natural infection of watermelon and pumpkin fruit has never been reported.
文摘This study was designed to bridge gap in nutritionally skewed available biscuits and the high volume of agricultural waste generated by investigating the quality of biscuits prepared from wheat base, supplemented with waste from watermelon rinds and orange pomace as possible nutritious alternatives. Biscuit samples were respectively produced from blends of wheat, watermelon rind and orange pomace in the following ratio 100:0:0;90:5:5;80:10:10;70:15:15 and 60:20:20, labelled samples A, B, C, D and E. F</span><span style="font-family:Verdana;">unctional, proximate, mineral and sensory properties of the formulated biscuit samples</span><span style="font-family:Verdana;"> were carried out using standard analytical procedures. The results showed that p</span><span style="font-family:Verdana;">roximate composition of samples B - E significantly increased (p < 0.05) except for carbohydrate content when compared with sample A used as control. </span><span style="font-family:Verdana;">There were also significant increases (p < 0.05) in mineral contents of supplemented samples compared to control. The result of the sensory evaluation showed that wheat flour can be substituted with watermelon rind and orange pomace flours up to 10% without adversely affecting the overall quality attributes of the biscuits. These results indicate the robustness of food value addition as an effective means of improving nutritional quality of biscuits while contributing to waste management in the agricultural value chain.
基金funded by grants from the China Agriculture Research System of MOF and MARA(Grant No.CARS-25)Special Scientific Research Service Fee of the Chinese Academy of Agricultural Sciences(Grant No.Y2019XK16-03)+2 种基金the Agricultural Science and Technology Innovation Program(Grant No.CAASASTIP-2021-ZFRI)Screening and technical demonstration and popularization of fruit and melon varieties in Xinjiang(Grant No.Y2021XK14)Special funds for basic research and special basic research(Grant No.20131602),Financial technology funding of Changji national agricultural science and technology park(Grant No.2021EK246).
文摘To balance the relationship between high yield and low nitrogen supply,the nitrogen utilization efficiency of watermelon needs to be improved urgently.Nodule inception-like Protein(NLP)transcription factors play a key node role in nitrate response and growth and development of plant,however,comprehensive analysis of the NLP gene family in watermelon is unclear.This study explored the functional classification,evolutionary characteristics,and expression profile of the ClNLP gene family.Three ClNLPs were categorized into three groups according to their gene structure and phylogeny.All of them contained the conserved RWP-RK and PB1 domains.Evolutionary analysis of ClNLPs revealed that ClNLP1 and ClNLP3 underwent strong purified selection.In addition,cis-acting elements related to plant hormones and abiotic stresses were present in the ClNLP promoter.According to tissue-specific analysis ClNLP was widely expressed in roots,stems,leaves,flowers and fruits,and ClNLP1 was significantly induced in the roots of different nitrogen utilization varieties under different nitrate nitrogen supply.The SRTING functional protein association network suggested that ClNLP1 is associated with most genes,such as NRT1.1,NRT2.1,NIA1,and NIR1,and the dual-luciferase reporter assay found that ClNLP1 positively regulates the expression of ClNRT2.1.We speculated that ClNLP1 might play a central role in regulating the response of watermelon to nitrate nitrogen.
基金supported by the Beijing Academy of Agricultural and Forestry Sciences (Grant Nos. KJCX201907-2, QNJJ201813, and KJCX20200303)the National Key Research and Development Program of China (Grant No. 2017YFD0102004)
文摘Watermelon(Citrullus lanatus)is one of the world’s most important fruit crops,and China produces the most watermelons in the world.Recently,a watermelon variome consisting of 414 key resequenced accessions was reported.However,the genetic relationships and pedigree of Chinese watermelon varieties in the seed market remain unclear.In this study,241 evenly distributed perfect single nucleotide polymorphisms(SNPs)derived from the watermelon variome were selected for variety identification.The diversity of 247 Chinese watermelon varieties was identified based on their SNP genotypes.The 247 watermelon varieties were clustered into five subpopulations:the East Asian ecotype,intermediate ecotype,small fruit with red flesh ecotype,small fruit with yellow flesh ecotype,and American ecotype.We further established the pedigree of four subpopulations,of which JingXinNo.1,ZaoChunHongYu,HuangXiaoYu and XiaoLan,and Sugarlee were the main doner of the East Asian ecotype,small fruit with red flesh ecotype,small fruit with yellow flesh ecotype,and American ecotype,respectively.Thirty-two core SNPs were selected and applied in watermelon variety identification.They were also validated by the Kompetitive allele-specific PCR(KASPar)platform.The present study furthered our understanding of the genetic relationships and pedigree of watermelon varieties in China,and will help to manage the plant variety protection in watermelon.
基金support provided by the National Natural Science Foundation of China(Grant No.31701939)National Natural Science Foundation of Shaanxi province,China(Grant No.2019JQ-324)+1 种基金National Key R&D Program of China(Grant No.2018YFD0100704)the Modern Agro-industry Technology Research System of China(Grant No.CARS-25).
文摘Proline accumulation has been shown to occur in plants in response to various environmental stresses.Although proline metabolismrelated genes have been functionally characterized,the inter-organ transport of proline in stressed plants remains unclear.In this study,free proline was detected with significant accumulations in the roots,stems,and leaves of watermelon drought-tolerant germplasm M08 and drought-susceptible line Y34 under drought stress.Expression profiling and enzyme activity measurements revealed that ClP5CS1 gene,rather than its paralog ClP5CS2,mainly contributes to the proline synthesis in leaves via the Glu pathway.Additionally,over-expression of the ClP5CS genes significantly enhanced the drought tolerance of transgenic Arabidopsis lines.Furthermore,we confirmed that proline is mainly synthesized in leaves and transported to roots in watermelon under drought stress.Transcriptome and expression analyses revealed that the genes involved in proline metabolism exhibited different expression levels.Specifically,ClP5CS1 was upregulated in leaves and roots,while ClP5CS2 was downregulated under drought stress.Also,415 and 362 differently expressed TFs were identified in roots and leaves,respectively,with the majority upregulated in the former.Ultimately,a model for proline metabolism was proposed.The findings of this study provided new insights into the biosynthesis,transport,and regulatory mechanism of drought-induced proline in plants.
文摘Carotenoids are responsible for the different flesh colors in watermelon fruit, such as white, salmon yellow, orange, pale yellow, canary yellow, crimson red, and scarlet red. In red-fleshed watermelons lycopene constitutes the major pigment and b-carotene the secondary. The predominant carotenoid in yellow-fleshed watermelon is neoxanthin. Lycopene content in watermelon is related to genotype and ploidy level, harvest maturity, and growth and development conditions. Watermelon flesh colors are controlled by several gene loci. There are two or three alleles identified at each gene locus. Up to now several full-length cDNAs or gene fragments encoding enzymes in the carotenoid metabolic pathway have been isolated and characterized from mature watermelon fruits. Differential expression of carotenogenic genes was examined in flesh, ovary, leaf, and root tissues across different colored fleshes (white, canary yellow, salmon yellow, orange, and red). Carotenogenic gene expression was also analyzed at three fruit developmental stages (10, 20, and 30 days postanthesis) in five flesh colors of watermelon cultivars (red, pink, orange, yellow, and white).
文摘Two field experiments were carried out at Akure (7oN, 5o101E) in the rainforest zone of Nigeria in 2006 and 2007 to determine the effectiveness of neem leaf, woodash and modified neem leaf extracts as fertilizer sources in improving soil fertility, growth and yield of maize (Zea mays L) and watermelon (Citrulus lanatus) sole and intercrop. There were six treatments namely, poultry manure, neem leaf extract (sole), woodash extract, modified neem leaf (neem leaf + woodash), NPK 15-15-15 and a control (no fertilizer nor extract), replicated three times and arranged in a randomized complete block design (RCB). The extracts (neem leaf, wood ash and modified neem leaf) were applied at 1200 litres per hectare each, NPK 15-15-15 at 300 kg/ha and poultry was applied at 6t/ha. The results showed that there were significant increases (P 2O), K, Ca, Mg, Na, O.M, P and N compared to NPK 15-15-15 and neem leaf extract. For instance, modified neem leaf extract increased soil pH (H2O), K, Ca, Mg, Na, O.M, P and N by 12.4%, 32.8%, 25%, 23.7%, 19.32%, 17.24% and 20% respectively compared to neem leaf extract under intercrop plot. The high soil K/Ca, K/Mg and P/Mg ratios in the NPK 15-15-15 fertilizer treatment led to an imbalance in the supply of P, K, Ca and Mg nutrients to maize and watermelon crops. The least values for growth, yield and soil parameters were recorded under the control treatment. In these experiments, modified neem leaf extract (woodash + neem leaf extracts) applied at 1200 litres/ha was the most effective in improving soil fertility, growth and yield of maize and watermelon (sole and intercrop) and could substitute for 6 tons per hectare of poultry manure and 300kg/ha of NPK 15-15-15 fertilizer.
