Low light is a major limiting factor in greenhouse grapevine cultivation, particularly during winter and early spring. To investigate the genetic basis of low light tolerance, a population of 198 F1 individuals derived from a cross between low light-tolerant and low light-sensitive grapevine varieties was used in this study. SNP markers were converted into bin markers using the self-developed VCF_to_binMap analysis pipeline, and a genetic map was constructed containing 19 linkage groups with a total length of 1161.95 cM and an average marker distance of 0.71 cM. Phenotypic analysis revealed significant segregation for chlorophyll content and light compensation point (LCP) in the F1 population, with traits approximately following a normal distribution. QTL mapping identified three significant QTLs associated with chlorophyll a content, four with chlorophyll b content, and one with total chlorophyll content, all located on linkage group LG17. Additionally, one significant QTL related to LCP was mapped to LG8. Transcriptome sequencing of extreme phenotype plants and correlation analysis identified two MYB transcription factors (Vitvi17g00232 and Vitvi17g00309) and one STN8-encoding gene (Vitvi08g02097) within the QTL intervals, suggesting their potential roles in low light tolerance. This study provides insights into the genetic mechanisms underlying low light tolerance in grapevines and identifies candidate genes for further functional validation. The findings contribute to the development of grapevine varieties with improved low light tolerance, supporting sustainable greenhouse cultivation practices.

The evaluation of fruit quality greatly relies on the presence of soluble sugars. In this study, we investigated the dynamics of soluble sugars and basic fruit quality of 'Zaozhong 6' loquat after the application of methyl jasmonate (MeJA). As loquats approached full ripeness, the study unveiled a notable increase in their soluble sugar content, predominantly attributed to the rise in fructose levels.. MeJA application accelerated sugar accumulation, suggesting its potential for expediting fruit maturation and enhancing sugar content. Importantly, MeJA-treated fully ripe loquats exhibited a significantly higher sugar-acid ratio. In addition to compositional analyses, the study delves into the molecular aspects of sugar metabolism. Despite the absence of detectable sucrose and glucose, the expressions of FK, HK, SPP, SPS, and SS genes were notably influenced, emphasizing the complex regulatory mechanisms governing sugar metabolism in loquat fruit. This research provides valuable insights into the temporal changes in sugar composition during loquat fruit development, underscores the role of MeJA in shaping these dynamics, and highlights the significance of the sugar-acid ratio in fruit quality determination.

Together with other polyphenols and flavonoids, anthocyanins have the capacity to serve as free radical scavengers against detrimental oxidants including reactive oxygen and nitrogen species. Moreover, the role of anthocyanin pigments as natural fruit colorings is quite common. In this study, the anthocyanin profile of purple and yellow passion fruit was determined at five developmental phases i.e., fruitlet, green, veraison, maturity, and ripening stage. Total flavonoids were abundantly found among other metabolites including anthocyanins and proanthocyanins. Purple passion fruits contained more than 2-times higher flavonoid content than yellow passion fruits at ripening stage. The findings showed that fruit maturation increased the amount of total flavonoids, anthocyanins, and procyanidins in the pulp of both varieties of passion fruit. Correlation analysis revealed that the passion fruit anthocyanin metabolism may be regulated by the enzymes C4H, 4CL, CHS, UFGT, and GST. The metabolism of anthocyanins in passion fruit may be significantly influenced by the genes PePAL4, PeCHS1, and PeGST7. New information from this work will help future research into the fundamental processes controlling the production of anthocyanins in passion fruit.

Plant surfaces are covered with cuticle wax and are the first barrier between a plant and environmental stresses. Eceriferum (CER) is an important gene family involved in wax biosynthesis and stress resistance. In this study, for the first time, 34 CER genes were identified in the passion fruit (Passiflora edulis) genome, and PeCER proteins varied in physicochemical properties. A phylogenetic tree was constructed and divided into seven clades to identify the evolutionary relationship with other plant species. Gene structure analyses revealed that conserved motifs ranged from 1 to 24, and that exons ranged from 1 to 29. The cis-element analysis provides insight into possible roles of PeCER genes in plant growth, development and stress responses. The syntenic analysis revealed that segmental (six gene pairs) and tandem (six gene pairs) gene duplication played an important role in the expansion of PeCER genes and underwent a strong purifying selection. In addition, 12 putative ped-miRNAs were identified to be targeting 16 PeCER genes, and PeCER6 was the most targeted by four miRNAs including ped-miR157a-5p, ped-miR164b-5p, ped-miR319b, and ped-miR319l. Potential transcription factors (TFs) such as ERF, AP2, MYB, and bZIP were predicted and visualized in a TF regulatory network interacting with PeCER genes. GO and KEGG annotation analysis revealed that PeCER genes were highly related to fatty acid, cutin, and wax biosynthesis, plant-pathogen interactions, and stress response pathways. The hypothesis that most PeCER proteins were predicted to localize to the plasma membrane was validated by transient expression assays of PeCER32 protein in onion epidermal cells. qRT-PCR expression results showed that most of the PeCER genes including PeCER1, PeCER11, PeCER15, PeCER17, and PeCER32 were upregulated under drought and Fusarium kyushuense stress conditions compared to controls. These findings provide a foundation for further studies on functions of PeCER genes to further facilitate the genetic modification of passion fruit wax biosynthesis and stress resistance.

The NAC gene family is one of the largest plant transcription factors (TFs) families and plays important roles in plant growth, development, metabolism, and biotic and abiotic stresses. However, NAC gene family has not been reported in passion fruit (Passiflora edulis). In this study, a total of 105 NAC genes were identified in the passion fruit genome and were unevenly distributed across all nine-passion fruit chromomere, with a maximum of 48 PeNAC genes on chromosome one. The physicochemical features of all 105 PeNAC genes varied including 120 to 3,052 amino acids, 3 to 8 conserved motifs, and 1 to 3 introns. The PeNAC genes were named (PeNAC001–PeNAC105) according to their chromosomal locations and phylogenetically grouped into 15 clades (NAC-a to NAC-o). Most PeNAC proteins were predicted to be localized in the nucleus. The cis-element analysis indicated the possible roles of PeNAC genes in plant growth, development, light, hormones, and stress responsiveness. Moreover, the PeNAC gene duplications including tandem (11 gene pairs) and segmental (12 gene pairs) were identified and subjected to purifying selection. All PeNAC proteins exhibited similar 3D structures, and a protein–protein interaction network analysis with known Arabidopsis proteins was predicted. Furthermore, 17 putative ped-miRNAs were identified to target 25 PeNAC genes. Potential TFs including ERF, BBR-BPC, Dof, and bZIP were identified in promoter region of all 105 PeNAC genes and visualized in a TF regulatory network. GO and KEGG annotation analysis exposed that PeNAC genes were related to different biological, molecular, and cellular terms. The qRT-PCR expression analysis discovered that most of the PeNAC genes including PeNAC001, PeNAC003, PeNAC008, PeNAC028, PeNAC033, PeNAC058, PeNAC063, and PeNAC077 were significantly upregulated under Fusarium kyushuense and drought stress conditions compared to controls. In conclusion, these findings lay the foundation for further functional studies of PeNAC genes to facilitate the genetic improvement of plants to stress resistance.

以紫色百香果为试材,采后分别用浓度0.2、1、2和5 mmol/L的水杨酸和蒸馏水(对照)浸泡10 min,常温贮藏6、12和18 d后测定其可溶性固形物、可滴定酸、抗坏血酸和可溶性糖等生理指标.结果表明,水杨酸处理18 d可显著提高百香果硬度和商品率,保持良好的外观色泽,并显著降低果实皱缩指数,同时有效延缓果实可溶性固形物、可滴定酸、抗坏血酸和可溶性糖含量的下降,保持较低的固酸比.综合各项指标,1 mmol/L浓度水杨酸处理的保鲜效果更优,果实品质更佳.

Passion fruit (Passiflora edulis) is an important fruit crop with high economic value. Genetic engineering plays an important role in crop improvement with desired traits and gene functional studies. The lack of a simple, efficient, and stable transformation system for passion fruit has greatly limited gene functional studies. In this study, a simple and efficient Agrobacterium-mediated in planta transformation system for passion fruit was established, using Agrobacterium virulent strain EHA105 harboring the binary vectors pCAMBIA1301 and pCAMBIA1302 with GUS and GFP reporter genes. The system requires less time and labor costs than conventional transformation systems, and no additional phytohormones and sterile conditions are required. Regeneration efficiency of 86% and transformation efficiency of 29% were achieved, when the wounds were wrapped with Parafilm and the plants were kept in darkness for 15 days. Approximately 75% of the regenerated plants had a single shoot and 26% multiple shoots. The transformation was confirmed at the DNA and RNA levels as well as by GUS staining and GFP fluorescent measurements. The developed protocol will contribute to the genetic improvement of passion fruit breeding.

Bagging regulates the fruit microenvironment and improves the quality and market value of fruits. It is a safe and ecofriendly technique to protect fruits from insect/pest infestation and multiple biotic and abiotic stresses. In the current study, the influence of fruit bagging was evaluated on the development and quality of loquat fruits. Fruits from a healthy loquat orchard (Cv. Zaozhong No.6), located in Fujian, China, were enveloped in paper (T1), aluminum (T2), and aluminum–polyethylene bags (T3), while unbagged fruits were maintained as control (T0). In general, fruit bagging improved fruit quality in terms of fruit physiological and biochemical attributes and protected fruits from physical damage. In particular, aluminum–polyethylene bagging enhanced fruit weight, length, and width by 1.37-, 1.18-, and 1.13-fold, respectively. Loquat fruits bagged with paper bags exhibited the maximum soluble sugar and lowest titratable acid content. Fruits treated with paper and aluminum–ethylene bags showed twofold higher sugar–acid ratio as compared to control. Aluminum–polyethylene bagging caused 66.67%, 55.56%, and 33.33% reductions in skin burn, fruit rotting, and black spot of loquat. The fruits bagged in aluminum and aluminum–polyethylene did not show insect or bird damage, while unbagged fruits had 14.70% and 17.65% insect and bird damage, respectively. Overall, the results suggest that paper, aluminum, and aluminum–polyethylene bagging improved fruit health by 75%, 131%, and 144%, respectively, as compared to control. To delineate bagging type-dependent effects, principal component analysis was performed. Paper bagging was positively correlated with fruit firmness, rotting, soluble sugars, sugar–acid ratio, and proline content. Aluminum bagging was highly associated with improvements in titratable acids, cystine, and methionine. Aluminum–polyethylene bags were correlated with fruit weight, size, peel thickness, edible rate, and certain amino acids.

Flavonoids play a key role as a secondary antioxidant defense system against different biotic and abiotic stresses, and also act as coloring compounds in various fruiting plants. In this study, fruit samples of purple (Passiflora edulis f. edulis) and yellow (Passiflora edulis f. flavicarpa) passion fruit were collected at five developmental stages (i.e., fruitlet, green, veraison, maturation, and ripening stage) from an orchard located at Nanping, Fujian, China. The contents of flavonoid, anthocyanin, proanthocyanin, and their metabolites were determined using ultra-performance liquid chromatography-mass spectrometry (UPLC-MS), activities of key enzymes involved in flavonoid metabolism were measured, and expression profiling of related genes was done using quantitative real-time PCR (qRT-PCR). The results revealed that total flavonoids, anthocyanins, and procyanidins were found to be increased in the fruit peel of both cultivars with fruit maturity. Total flavonoids, anthocyanins, procyanidins, flavonoid metabolites (i.e., rutin, luteolin, and quercetin), and anthocyanin metabolites (i.e., cyanidin-3-O-glucoside chloride, peonidin-3-O-glucoside, and pelargonidin-3-O-glucoside) were found abundant in the peel of purple passion fruit, as compared to yellow passion fruit. Principle component analysis showed that the enzymes, i.e., C4H, 4CL, UFGT, and GST were maybe involved in the regulation of flavonoids metabolism in the peel of passion fruit cultivars. Meanwhile, PePAL4, Pe4CL2,3, PeCHS2, and PeGST7 may play an important role in flavonoid metabolism in fruit peel of the passion fruit. This study provides new insights for future elucidation of key mechanisms regulating flavonoids biosynthesis in passion fruit.

目的 优化余甘子果实总黄酮提取工艺.方法 选用余甘子'兰丰'果实为试材,利用单因素试验结合响应面分析法,研究乙醇浓度、料液比、水浴时间、水浴温度4个因素对余甘子鲜样和干样总黄酮提取的影响.结果 余甘子鲜样总黄酮最佳提取条件为:乙醇浓度70％,料液比1:25(g:mL),水浴时间45 min,水浴温度40℃,总黄酮理论含量30.70 mg/g,实际平均含量为30.49 mg/g.余甘子干样最佳提取条件为:乙醇浓度60％,料液比1:20(g:mL),水浴时间60 min,水浴温度60℃,总黄酮理论含量30.04 mg/g,实际平均含量29.72 mg/g.总黄酮提取含量鲜样大于干样,增加了2.56％.结论 响应面分析法对试验结果的优化可靠有效.使用余甘子鲜样提取总黄酮,相比使用干样,在条件适宜地区更为经济.

Aluminum-activated malate transporters (ALMTs) have multiple potential roles in plant metabolism such as regulation of organic acids in fruits, movement of guard cells and inducing tolerance against aluminum stress. However, the systematic characterization of ALMT genes in loquat is yet to be performed. In the current study, 24 putative ALMT genes were identified in the genome of Eriobotrya japonica Lindl. To further investigate the role of those ALMT genes, comprehensive bioinformatics and expression analysis were performed. In bioinformatics analysis, the physiochemical properties, conserved domains, gene structure, conserved motif, phylogenetic and syntenic analysis of EjALMT genes were conducted. The result revealed that the ALMT superfamily domain was conserved in all EjALMT proteins. EjALMT proteins were predicted to be localized in the plasma membrane. Genomic structural and motif analysis showed that the exon and motif number of each EjALMT gene ranged dramatically, from 5 to 7, and 6 to 10, respectively. Syntenic analysis indicated that the segmental or whole-genome duplication played a vital role in extension of the EjALMT gene family. The Ka and Ks values of duplicated genes depicted that EjALMT genes have undergone a strong purifying selection. Furthermore, the expression analysis of EjALMT genes was performed in the root, mature leaf, stem, full-bloom flower and ripened fruit of loquat. Some genes were expressed differentially in examined loquat tissues, signifying their differential role in plant growth and development. This study provides the first genome-wide identification, characterization, and relative expression of the ALMT gene family in loquat and provides the foundation for further functional analysis.

SWEET糖转运蛋白在植物生长发育、生物和非生物胁迫反应中发挥了重要作用.为了解李果实SWEET基因的序列特性及其在果实发育过程中的表达模式,以'皇冠李'果实为材料,采用聚合酶链式反应技术分别克隆两个SWEET基因cDNA和DNA序列全长,进行系统生物信息学分析,同时利用实时荧光定量技术研究它们在果实不同发育时期的表达情况,并分析与果实糖含量变化间的相关性.结果 显示:李SWEET基因PsSWEET2a-like和PsSWEET17-like的cDNA序列长度分别为627 bp和597 bp,它们的编码蛋白分别隶属于SWEET家族的Ⅰ亚簇和Ⅳ亚簇,均为包含典型的Mtn3/saliva结构域的疏水性碱性蛋白.随着果实的发育,PsSWEET2a-like呈下调表达,而PsSWEET17-like呈上调表达.相关性分析显示皇冠李果实发育过程中,PsSWEET17-like与果糖和葡萄糖含量变化显著正相关,与蔗糖显著负相关,而PsSWEET2a-like与这3种糖含量均不相关.本研究表明李果实发育后期PsSWEET17-like表达显著,在葡萄糖、果糖积累和果实生长发育中可能发挥了重要作用;PsSWEET2a-like在果实糖的转运调控中无显著作用,可能更多参与植物其他生物过程.

'仕坂晚柰'是从古田县鹤塘镇西洋村柰李选种圃油柰中经无性系选育出来的晚熟油柰(Prunus salicina Lindl.var.cordata)新品种.果实近扁圆形,微凸,果实有空腔,果皮浅黄色或黄色带绿,果面光滑,果粉厚,成熟果肉为淡黄色,口味酸甜;平均单果质量为108.5g,可溶性固形物含量(w,后同)为11.81％～12.50％,可滴定酸(以苹果酸计)含量为0.60％～0.76％,可食率为96.5％,富含抗氧化作用的功能物质.在福建古田(E119°09′39.01″,N 26°67′52.02")8月中下旬—9月初成熟,成熟期比普通油柰晚20～25 d.具有较强的抗旱抗寒能力,适宜在福建省桃李适栽区种植,成年树每666.67 m2产量可达2 850 kg(每666.67 m2 37株).

[目的]研究香蕉水通道蛋白(AQP)基因家族密码子使用特点,为其基因编码规律及功能和分子进化研究提供依据.[方法]采用CodonW、SPSS、Origin等软件分析香蕉AQP基因家族密码子偏好性.[结果]从香蕉基因组中鉴定获得54条香蕉AQP基因,其中包括9条NIPs、21条PIPs、4条SIPs和20条TIPs.香蕉AQP基因家族A、T、C、G出现频率平均值分别为12.0％、15.9％、52.3％和37.4％,平均GC3s含量为75.8％,ENc值在31.0～60.7,平均值为42.9;SIPs、NIPs、PIPs和TIPs分别有2、5、7和6个最优密码子,且多以C结尾,少数以G结尾;ENc和CAI呈极显著负相关,说明密码子第3位碱基会影响基因表达能力.[结论]香蕉AQP家族基因密码子偏好性较弱,偏好使用G和C且以G/C结尾的密码子,PIPs和TIPs密码子偏好性受自然选择的影响较大,而NIPs和SIPs受碱基突变的影响较大.

通过盆栽试验,研究不同剂量的枯草芽孢杆菌Bacillus subtilis对嘉宝果Myrciaria cauli flora Berg实生苗地上部生长量和叶绿素含量的影响.结果表明:枯草芽孢杆菌在一定程度上对嘉宝果的株高、茎粗、冠幅、各主枝新梢数、各主枝最长新梢以及叶绿素含量均有促进作用.其中,每盆3 g的枯草芽孢杆菌对嘉宝果的促生作用最为显著.栽培生产中将枯草芽孢杆菌剂量范围控制在每667m2900～1 800 g对促进嘉宝果生长发育最为适宜.

为改善3年生嘉宝果(Myrciaria cauliflora Berg)的栽培基质并促进其生长和发育,通过田间盆栽试验研究了有机碳对其实生苗地上部生长量和叶绿素含量的影响.结果表明:有机碳对嘉宝果实生苗地上部生长量和叶绿素含量均有一定的促进作用,以每盆150 mL有机碳效果最为显著.生产中将有机碳剂量控制在每盆100～200 mL对改良嘉宝果生长的土壤基质最为适宜,能有效促进其生长发育.

[目的]揭示不同激素和非生物逆境处理下非洲菊SOD活性变化趋势.[方法]对非洲菊进行ABA、SA、高盐、干旱(PEG模拟)和低温处理,测定处理前后SOD酶活性.[结果]在处理时间内,ABA对非洲菊SOD活性没有显著影响,SA则极显著抑制SOD活性.在高盐处理下,非洲菊SOD活性表现出先升高后降低的趋势;PEG模拟干旱处理下,SOD活性极显著下调(P<0.01).低温处理极显著抑制SOD活性(P<0.01),SOD活性变化趋势为先降低再升高.[结论]非洲菊SOD活性在不同逆境处理下表现出不同的变化趋势;该研究可为揭示SOD在非洲菊抗逆防御反应中的作用规律奠定基础.