HD-Zip Transcription Factor is Responsible for No-Lobed Leaf in Watermelon(Citrullus lanatus L.)

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.

Identification of candidate genes that regulate the trade-off between seedling cold tolerance and fruit quality in melon (Cucumis melo L.)

Trade-offs between survival and growth are widely observed in plants.Melon is an annual,trailing herb that produces economically valuable fruits that are traditionally cultivated in early spring in China.Melon seedlings are sensitive to low temperatures,and thus usually suffer from cold stress during the early growth period.However,little is known about the mechanism behind the trade-offs between seedling cold tolerance and fruit quality in melon.In this study,a total of 31 primary metabolites were detected from the mature fruits of eight melon lines that differ with respect to seedling cold tolerance;these included 12 amino acids,10 organic acids,and 9 soluble sugars.Our results showed that concentrations of most of the primary metabolites in the cold-resistant melons were generally lower than in the cold-sensitive melons;the greatest difference in metabolite levels was observed between the cold-resistant line H581 and the moderately cold-resistant line HH09.The metabolite and transcriptome data for these two lines were then subjected to weighted correlation network analysis,resulting in the identification of five key candidate genes underlying the balancing between seedling cold tolerance and fruit quality.Among these genes,CmEAF7 might play multiple roles in regulating chloroplast development,photosynthesis,and the ABA pathway.Furthermore,multi-method functional analysis showed that CmEAF7 can certainly improve both seedling cold tolerance and fruit quality in melon.Our study identified an agriculturally important gene,CmEAF7,and provides a new insight into breeding methods to develop melon cultivars with seedling cold tolerance and high fruit quality.

Melon short internode(CmSi)encodes an ERECTA-like receptor kinase regulating stem elongation through auxin signaling

Plant height is one of the most important agronomic traits that directly determines plant architecture,and compact or dwarf plants can allow for increased planting density and land utilization as well as increased lodging resistance and economic yield.At least four dwarf/semidwarf genes have been identified in different melon varieties,but none of them have been cloned,and little is known about the molecular mechanisms underlying internode elongation in melon.Here,we report map-based cloning and functional characterization of the first semidwarf gene short internode(Cmsi)in melon,which encodes an ERECTA-like receptor kinase regulating internode elongation.Spatial-temporal expression analyses revealed that CmSI exhibited high expression in the vascular bundle of the main stem during internode elongation.The expression level of CmSI was positively correlated with stem length in the different melon varieties examined.Ectopic expression of CmSI in Arabidopsis and cucumber suggested CmSI as a positive regulator of internode elongation in both species.Phytohormone quantitation and transcriptome analysis showed that the auxin content and the expression levels of a number of genes involved in the auxin signaling pathway were altered in the semidwarf mutant,including several well-known auxin transporters,such as members of the ABCB family and PINFORMED genes.A melon polar auxin transport protein CmPIN2 was identified by protein–protein interaction assay as physically interacting with CmSI to modulate auxin signaling.Thus,CmSI functions in an auxin-dependent regulatory pathway to control internode elongation in melon.Our findings revealed that the ERECTA family gene CmSI regulates stem elongation in melon through auxin signaling,which can directly affect polar auxin transport.

Development of branchless watermelon near isogenic lines by marker assisted selection

Pruning is time-consuming and laborious in watermelon cultivation,which can not meet the needs for simplified cultivation in the future.The development of branchless lines will provide important germplasms for breeding watermelon varieties and is an important method for genetic improvement.In this study,the watermelon accession,Wu Cha Zao(WCZ)is a branchless inbred line that carries the branchless gene Clbl,which was used as the donor parent to develop branchless near isogenic lines(NILs).To construct the NILs of Clbl,WCZ crossed with the normal branching watermelon inbred line WT20 which was used as the recurrent parent.The co-segregating markers dCAPS10 and Indel1 with Clbl were used for foreground selection,and a total of 108 SSR markers was selected with good polymorphism between two parental lines for background selection which had relatively uniform distribution across 11 chromosomes.Using these markers to select individuals from the BC_(1)F_(1),BC_(2)F_(1),and BC_(2)F_(2) generations,three NILs with a proportion of recurrent parent genome(PRPG)>99%were finally obtained.The lateral branch and plant height phenotypes did not significantly differ between the NILs and WCZ,indicating that the NILs of Clbl under the genetic background of WT20 has been successfully developed.These results provide ideal materials for further in-depth analysis of the genetic mechanisms of lateral branch development and ideal plant architecture breeding in watermelon.

One-step Fabrication of Cellulose/Graphene Conductive Paper

In this study,a straightforward,one-step wet-end formation process was employed to prepare cellulose/graphene conductive paper for antistatic packing materials.Cationic polyacrylamide was introduced into the cellulose/graphene slurry to improve the graphene loading on the surfaces of the cellulose fibers.The effect of the super calender process on the properties of the cellulose/graphene conductive paper was investigated.When 55 wt% graphene was added,the volume resistivity of the cellulose/graphene conductive paper was 94.70 W·cm,decreasing to 35.46 W·cm after the super calender process.The cellulose/graphene conductive paper possessed excellent anti-static ability and could be used as an anti-static material.

Cationized Melamine-formaldehyde Resin for Improving the Wet Strength of Paper

In this work, melamine-formaldehyde resin was cationized by adding modifiers so that the fibers closely bonded to improve their usability and the wet strength of paper was greatly improved. Triethanolamine and dimethylamine were added to modify the melamine-formaldehyde resin,respectively.The mechanism of the cationized resin was explored and the possible chemical reactions were deduced. It was concluded that,with the use of triethanolamine,the most optimum product was obtained by hydroxymethylation for 30 min with a temperature of 85℃ and p H of 9. 0 where n( melamine) ∶ n( formaldehyde) ∶ n( methanol) ∶ n( triethanolamine) was 100 ∶ 330 ∶ 450 ∶ 15. With the combined use of dimethylamine and methanol,the optimal product was acquired by condensation for 30 min at a temperature of 50℃ and p H of 2. 0 at melamine, formaldehyde, methanol, and dimethylamine molar ratio of100∶ 330∶ 350∶ 20. With the only use of dimethylamine,the optimal product was obtained by condensation at melamine,formaldehyde,dimethylamine molar ratio of 100∶ 330∶ 10. The wet tensile strength of fruit-bagging paper was improved by adding cationized melamine-formaldehyde resin. The zeta potential,charge density,and conductivity of the melamine-formaldehyde resin were also studied.

Evaluation of E-commerce Poverty Alleviation Effect in the Context of Rural Revitalization Strategy

The industrial prosperity proposed in the overall requirement of rural revitalization strategy in the Report of the 19th National Congress is the cornerstone of rural development. E-commerce poverty alleviation is an effective way of poverty alleviation in recent years. This paper mainly explored the factors influencing the rural e-commerce poverty alleviation and the evaluation of poverty alleviation effects,in order to come up with countermeasures and recommendations to provide assistance and guidance for the use of e-commerce to achieve poverty alleviation and accordingly to revitalize the rural industry. Firstly,using the literature research method,it proposed four level Ⅰ indicators influencing the e-commerce poverty alleviation,and designed a detailed level Ⅱ indicator system under each dimension. Then,the questionnaire survey method was employed to collect data for SPSS analysis to verify whether the designed indicator system is correct. Finally,it analyzed the problem of the current stage of e-commerce poverty alleviation by means of the quadrifid graph,and came up with corresponding countermeasures on the basis of the four key levek I factors.

Does weight loss affect the center of pressure of children with obesity: a follow-up study

Background:Children with obesity were found to show the greater postural instability compared to the normal-weighted children.However,it’s still unclear if their altered postural control ability would recover towards normal pat-tern after weight loss.The purpose of this study was to investigate the effect of weight loss on the center of pressure(COP)for obese children.Method:Totally 147 children were conducted a follow-up study in three years.A total number of 22 participants aged 7-13 years were recruited for their remission of obesity problem after 36 months.Their dynamic plantar pressure data were collected by Footscan pressure plate.The normalized time of four sub-phases,displacements and velocities of COP in anterior-posterior(AP)and medial-lateral(ML)directions were calculated to perform the Kolmogorov-Smirnov test and paired sample t test for statistical analyses.Results:After weight loss,children’s normalized time of forefoot contact phase(FFCP)increased significantly,and their duration of flat foot phase(FFP)decreased significantly.They also exhibited the more medial and posterior ori-entated COP path after weight loss.In ML-direction,the COP displacement during FFP and FFPOP increased,and the COP velocity during FFPOP increased.In AP-direction,COP velocity during FFP and FFPOP increased.Conclusions:The findings indicated that weight loss would have effects on the COP characteristics and postural stability for obese children.COP trajectory can provide essential information for evaluating foot function.The findings may be useful for obese children,medical staff,and healthcare physician.

Differences in loading patterns between fast walking and jogging at the same speed in male adults

Fast walking and jogging are two common exercises for people to maintain health in daily life.But the differences in loading patterns of fast walking and jogging are still unclear.The purpose of this study was to compare loading patterns in fast walking and jogging at the same speed,and to identify how differences in foot mechanics influence plantar pressure distribution between the two modes of gait.Totally,49 healthy males participated in this study.Data of pressure parameters,including maximum force(MF),peak pressure(PP),contact area(CA),force-time integral(FTI),were recorded by Pedar-X insole plantar pressure measurement system in participants’fast walking and jogging process at 7 km/h.A Load transfer analysis method was used to quantify the plantar load transference from fast walking to jogging.The results showed that MF,PP and CA increased in metatarsal regions and midfoot regions while decreased in toes regions and heel during jogging when compared with fast walking.FTI decreased in all foot regions during jogging compared to fast walking.Under the effects of spring mechanics and the varus of rearfoot during jogging,fast walking and jogging reveal different loading patterns.Compared jogging to fast walking,load transferred as follow:1)in transverse direction,load transferred from lateral foot to medial foot in metatarsal regions and midfoot regions,2)in longitudinal direction,load transferred from toes to the metatarsal,and from heel to the metatarsal and midfoot.These results also provide suggestions for footwear designs.