Loquat (Eriobotrya japonica Lindl.) is a subtropical evergreen fruit tree that accumulates abundant bioactive triterpene compounds with diverse pharmaceutical activities. Its leaves have been used in traditional Chinese medicine for over 1000 years. Methyl jasmonate (MeJA) is a conserved elicitor that stimulates plant secondary metabolism. However, the regulatory mechanisms of terpenoid biosynthesis after MeJA treatment in loquat callus remain largely unknown. In this study, we employed an integrated targeted metabolomic and transcriptomic approach to investigate the effect of exogenous MeJA on terpenoid biosynthesis in loquat callus. In total, 131 terpenoid compounds were detected, including 112 triterpenes, six triterpene saponins, seven diterpenoids, three sesquiterpenoids and three monoterpenoids. After MeJA treatment, a total of 55 and 33 differential metabolites (DEMs) were identified at 24 h and 48 h, respectively. Most DEMs were triterpene compounds, displaying increased accumulation. Among them, ursolic acid showed the highest accumulation at 24 h, and betulinic acid was most abundant at 48 h. Meanwhile, transcriptome analysis showed significant upregulation of terpenoid biosynthesis genes, including EjFPSs, EjSQEs, EjOSC2 and EjCYP716A2, as well as genes related to jasmonic acid (JA)-mediated signaling and JA-responsive genes in loquat callus treated with MeJA. Overall, these results provide a deeper understanding of the mechanism of terpenoid accumulation in loquat callus induced by MeJA and establish a theoretical basis for utilizing plant cell culture techniques to achieve production of the valuable terpenoid metabolites that are applied in the functional food and pharmacological industries.

Loquat fruits from the apple tribe of Rosaceae ripen from late spring to early summer, when most fresh fruits are out of season. Compared with the orange-fleshed varieties, the white-fleshed varieties are usually preferentially chosen by consumers for a more favorable flavor. Though the breeding of white-fleshed cultivars with large fruit size greatly promoted the development of loquat production, the mechanisms of how fruits with lighter pigments are generated and how fruit flavor changes following flesh color shifting remain to be elucidated. Pigment measurements indicated carotenoids as the dominant pigment underlying the change in flesh color changing. Genotyping and haplotyping of 807 loquat accessions revealed that the rise of PSY2Ad-PSY2Ad genotype blocks carotenoids accumulation and confers to white flesh color of loquat fruit. Analysis of widely targeted metabolomes on 18 representative cultivars identified 1420 metabolites, with 223 differentially accumulated metabolites between the two groups. Further metabolite comparison demonstrated that low levels of bitter or astringent compounds, such as flavonoids, lignans and coumarins, phenolic acids, nucleotides, alkaloids, and terpenoids, may confer to a refreshing flavor of white-fleshed fruits. Furthermore, 18 metabolic biomarkers were identified by machine learning to distinguish fruits with diverse flesh colors. This work gives insights into the understanding of how fruit color variation associated with flavor and also promotes white-fleshed loquat breeding by genus-wide genotyping.

Aroma is a crucial factor influencing the flavor quality and economic value of longan fruits. This study employed a mapping population consisting of 98 F1 progeny of ‘Shixia × Xiangcui’ (exhibiting broad segregation in fruit aroma trait) and their parents. We performed the SNP genotyping through whole-genome resequencing to construct a high-density linkage map, followed by QTL mapping and candidate gene screening for aroma trait. We obtained a total of 554.9 Gbp of sequencing data, with an average depth of approximately 15× for the parents and 12× for the progeny. Three types of SNP markers (lm×ll, nn×np, and hk×hk) were developed, totaling 317 877. After merging with a 100 kb sliding window, 6 134 Bin markers were generated. A first high-density Bin map was constructed, comprising 15 linkage groups with 3 517 Bin markers (containing 264 385 SNPs), covering a total map length of 1 666.79 cM. The average marker interval was 0.48 cM, with 99.18% of gaps being less than 5 cM. Collinearity analysis confirmed the high quality of the map. Fifty-six QTLs were mapped for 9 aroma-related traits, including (E)-2-hexenal, ethyl acetate, ethyl butyrate, ethyl crotonate, (E)-2-hexenoate, ethanol, linalool, ocimene, and total ester content. These QTLs explained 19.8%–51.0% of the phenotypic variation rates and were distributed across 11 linkage groups, with two QTL-rich regions on LG7 and LG8. Seven pleiotropic QTLs were detected. By analyzing the expression patterns of 1 535 annotated genes within the mapped intervals, six candidate genes potentially regulating the synthesis of ester characteristic aroma compounds were identified: aldo-keto reductase AKRs, acetolactate synthase small subunit ALS2, ACC oxidase ACO1-1, and transcription factors bHLH122, AGL103, and bZip1. This work provides novel insights into the fruit aroma formation, and facilitates breeding efforts to improve quality in longan and potentially other fruit crops.

Loquat (Eriobotrya japonica Lindl.) is a subtropical evergreen tree native to China. Generally, the pigments accumulated in the fruits of cultivated loquats are carotenoids rather than anthocyanins. In this study, we showed that the peel of 'Shanpaisanhao' loquats can accumulate anthocyanins and turn red. We further investigated the mechanisms underlying anthocyanin accumulation in the red-pigmented peels of 'Shanpaisanhao' loquats. RNA-seq analysis demonstrated that anthocyanin accumulation in loquat peel is associated with the upregulation of anthocyanin biosynthetic and transport genes as well as the transcriptional factor EjMYB10. Transient overexpression and dual luciferase assays showed that EjMYB10 could induce weak anthocyanin accumulation in tobacco leaves when co-expressed with PsbHLH3, and activate the promoters of EjF3'H, EjANS and EjUFGT. These results provide information for further elucidating the molecular mechanism of anthocyanin accumulation in the peel of SP3H loquat and for breeding of new red-pigmented loquat cultivars.

Longan is an exotic tropical fruit crop and exhibits off-season flowering induced by potassium chlorate (KClO3), though the molecular mechanisms remain unclear. We assembled a high-quality, 441.5 Mb genome of variety 'Shixia', with a contig N50 at 28.1 Mb, 29, 325 protein-coding genes, 26 telomeres and 15 centromeres. Comparative genomic analysis with lychee revealed structural variations potentially driving gene family expansions related to flavone biosynthesis and disease resistance. Transcriptomic profiling showed that natural flowering appears to be primarily regulated by photoperiod, vernalisation and autonomous pathways, while KClO3-induced flowering may preferentially activate the gibberellin pathway at 5 days after treatment (DAT) and autonomous pathways at 10 DAT, involving putative repression of DlDDF1, DlFLCs and DlSVPs, and up-regulation of DlWRKY75_2. In the perpetual-flowering variety 'Sijimi', elevated expression of photoperiod genes, such as DlCOR28, DlCOR27, DlADO3, DlPRR5, DlGI and DlJMJ30, may explain its perpetual blooming. Overexpression of DlDDF1 in Arabidopsis delayed flowering, partially reversed by KClO3 through an increase in bioactive GA4. Together, KClO3-induced flowering likely involves oxidative stress response and gibberellin signalling via DlDDF1 repression, while natural flowering relies on seasonal cues. These results lay the foundation for longan genetic improvement.

Eriobotrya japonica (loquat) is an evergreen fruit tree of the apple tribe in Rosaceae with high edible and medicinal value. The yield and quality of loquat fruits are significantly influenced by environmental stress, particularly heat stress during fruit ripening. In this study, thirty EjHSFs were identified in the loquat genome. Twenty-nine EjHSFs were unevenly distributed across sixteen chromosomes, except Chr-6. A synteny analysis revealed that twenty-six EjHSF genes had undergone duplication events. Twenty-nine EjHSF genes were found to be in sync with HSF in apples while also diverging with other Rosaceae species. A phylogenetic analysis revealed that EjHSFs could be divided into three categories, including eighteen EjHSF-A, ten EjHSF-B, and two EjHSF-C. Twenty-nine members of the EjHSF family showed high homology to those of Malus domestica and Gillenia trifoliate. A promoter analysis retrieved thirty-three CAREs that were functionally relevant and connected to the expression of HSFs. Among these, the promoters of twenty-three EjHSF genes possessed at least one STRE element that could be activated by heat shock. Eleven of these EjHSFs were highly expressed in loquat tissues, namely EjHSF-B4a, EjHSF-A4a, EjHSF-A4d, and EjHSF-C1a in roots; EjHSF-B4b in roots and inflorescence; EjHSF-C1b in stems and roots; EjHSF-A2a in three tissues; EjHSF-A8b in four tissues; and EjHSF-A4c, EjHSF-B1a, and EjHSF-B2b in six tissues. Moreover, fifteen EjHSFs were differentially expressed (eleven upregulated and four downregulated) in fruits under heat stress treatment in the color-changing period. Among them, EjHSF-A2a and EjHSF-A2b upregulated transcriptional abundance over 300 times after heat treatment; EjHSF-B2b consistently displayed an increasing trend over time; and EjHSF-B1a was significantly downregulated. Hence, these results suggest that EjHSFs take part in loquat tissue development and may be involved in the fruit’s heat stress response. These findings enhance the understanding of EjHSFs’ role within loquats and the heat stress response of its fruit and provide target genes for heat stress improvement.

Loquat is an evergreen fruit crop which blooms from autumn–winter, and supports human beings with juicy fruit from late spring to early summer. However, the most traditional cultivars of this crop produce small fruit and bear a much lower yield than its relatives like apple, pear and peach. Large-size cultivars have long been a cherished aim of breeders for improving the production yield of loquat. Agronomic practices like panicle thinning, fruit thinning, growth regulator application, fertilization and so on are easier and more accessible ways for growers to produce large-size loquat fruit on existing production trees. Here, we develop a novel pruning method with an annual double back-cut, which provides vigorous shoot with more leaves and thicker branches for bearing much larger loquat fruit. Cellular observation determined that the vigorous shoot training method motivated cell division to produce larger loquat fruit, and that most of these cell layers were proliferated before the appearance of flower blossoms. Gene expression data of four development stages showed that EjFWL1 and EjFWL2 were notably downregulated in flower buds of the vigorously pruned tree. The data here further confirmed that the cell division capacity during flower development greatly influenced both the flower and fruit size of loquat. More importantly, we developed a novel pruning method to inhibit cell division repressors, promote cell proliferation and enlarge fruit size in loquat.

福圆是立冬本×青壳宝圆的杂交子代,通过选择优良单株,定向培育而成的晚熟优质大果型龙眼新品种.树势中庸,成花易、高坐果率、早丰产;果皮青褐色,果实侧偏圆形,大小均匀,平均单果质量14.6 g;果肉乳白色、半透明,肉质细嫩、较易离核,可溶性固形物含量(w,后同)21.9％,还原糖含量6.5 g·100 g-1,总糖含量17.9 g·100 g-1,维生素C含量90.7 mg·100 g-1,可食率69.4％,味浓甜,品质佳.在福州地区,果实9月中下旬成熟;高接后3年生树平均果穗质量1190.5 g,平均株产7.2 kg;4年生树平均果穗质量1212.6 g,平均株产18.1 kg;丰产、稳产性好,连年结果能力强.适宜在福建福州、四川泸州、重庆万州及相似生态区栽培.

Eriobotrya is an evergreen fruit tree native to South-West China and adjacent countries. There are more than 26 loquat species known in this genus, while E. japonica is the only species yet domesticated to produce fresh fruits from late spring to early summer. Fruits of cultivated loquat are usually orange colored, in contrast to the red color of fruits of wild E. henryi (EH). However, the mechanisms of fruit pigment formation during loquat evolution are yet to be elucidated. To understand these, targeted carotenoid and anthocyanin metabolomics as well as transcriptomics analyses were carried out in this study. The results showed that β-carotene, violaxanthin palmitate and rubixanthin laurate, totally accounted for over 60% of the colored carotenoids, were the major carotenoids in peel of the orange colored 'Jiefangzhong' (JFZ) fruits. Total carotenoids content in JFZ is about 10 times to that of EH, and the expression levels of PSY, ZDS and ZEP in JFZ were 10.69 to 23.26 folds to that in EH at ripen stage. Cyanidin-3-O-galactoside and pelargonidin-3-O-galactoside were the predominant anthocyanins enriched in EH peel. On the contrary, both of them were almost undetectable in JFZ, and the transcript levels of F3H, F3'H, ANS, CHS and CHI in EH were 4.39 to 73.12 folds higher than that in JFZ during fruit pigmentation. In summary, abundant carotenoid deposition in JFZ peel is well correlated with the strong expression of PSY, ZDS and ZEP, while the accumulation of anthocyanin metabolites in EH peel is tightly associated with the notably upregulated expressions of F3H, F3'H, ANS, CHS and CHI. This study was the first to demonstrate the metabolic background of how fruit pigmentations evolved from wild to cultivated loquat species, and provided gene targets for further breeding of more colorful loquat fruits via manipulation of carotenoids and anthocyanin biosynthesis.

[目的]分析比较避雨设施葡萄下微生态环境对套种枇杷生长与结果的影响,为探讨葡萄-枇杷套种模式提供依据.[方法]在5年生避雨设施葡萄下套种盆栽带花蕾的新白8号枇杷3年生嫁接营养袋大苗,以露地盆栽带花蕾的新白8号枇杷3年生嫁接营养袋大苗为对照,连续2a(年)观测比较枇杷树体生长发育和果实质量差异.[结果]避雨设施栽培葡萄的生长,使夏季(中午12:00)棚内光照度降低了92.37%,温度降低6.10℃,相对湿度提高20.87%;冬季棚内温度提高1.15～2.28℃.避雨设施葡萄下套种盆栽枇杷树第2年的南北冠幅、树高度、干周、叶幕层厚、枝梢数、枝梢质量、叶片质量显著降低,花穗数、花穗大小显著低于对照;单株产量是对照的69.67%,显著低于对照;果穗质量、单果质量、可食率与对照差异不显著;果实病虫害明显减少,好果率提高12.89%～27.25%.[结论]避雨设施葡萄下套种的枇杷可正常开花结果,有一定产量,且果实病虫害减少,是一种可行的套种模式,但需进一步研究适宜的配套栽培技术,缓解避雨设施和葡萄生长对套种枇杷生长的荫蔽影响.

枇杷花被批准为新食品资源后,有望成为传统枇杷产业提质增效的突破口.本研究以Citespace软件生成的图谱为基础,分析我国枇杷花功能的研究现状,挖掘研究热点.以CNKI、WOS平台中枇杷花功能的文献为数据源,运用Citespace软件绘制年度发文量、关键词共现、关键词聚类、高突现词等可视化图谱.结果显示,检索到相关文献122篇,来自中国的118篇(占96.7％),日本2篇(占1.6％),伊朗和意大利均为1篇(仅占0.8％).枇杷花功能的研究报道最早从1999年开始,主要分为3个阶段:第1阶段(1999-2006年),枇杷花功能研究的起步期;第2阶段(2007-2014年),研究发展期,年度发文量均在5篇以上;第3阶段(2015-至今),研究的快速上升期,年度发文量10篇左右.该领域出现频次较高的关键词有枇杷花(93次)、黄酮(23次)、止咳(15次)等,中心度较高的关键词有三萜酸(0.72)、枇杷花(0.69)、止咳(0.66)等,高突现词有黄酮、三萜酸、蛋白质等.枇杷花功能的总体发文量偏低,但呈上升趋势,中国在该领域的研究优势明显.当前的研究热点是枇杷花功能成分的止咳功效及其机制研究.未来枇杷花研发将呈现多元化的趋势,基础研究多着重在发掘枇杷花的新活性成分,阐明其作用机制,应用领域主要在枇杷花产品的开发.

Fruit weight is an integral part of fruit quality and directly influences the commodity value and economic return of fruit crops. Despite the importance of fruit weight, its underlying molecular mechanisms remain understudied, especially for perennial fruit tree crops such as cultivated loquat (Eriobotrya japonica Lindl.). Auxin is known to regulate fruit development, but its role and metabolism during the development of loquat fruit remain obscure. In this study, we used a multi-omics approach, integrating whole-genome resequencing-based quantitative trait locus (QTL) mapping with an F1 population, population genomics analysis using germplasm accessions, transcriptome analysis, and metabolic profiling to identify genomic regions potentially associated with fruit weight in loquat. We identified three major loci associated with fruit weight, supported by both QTL mapping and comparative genomic analysis between small- and large-fruited loquat cultivars. Comparison between two genotypes with contrasting fruit weight performance by transcriptomic and metabolic profiling revealed an important role for auxin in the regulation of fruit development, especially at the fruit enlargement stage. The multi-omics approach identified homologs of ETHYLENE INSENSITIVE 4 (EjEIN4) and TORNADO 1 (EjTRN1) as promising candidates for the control of fruit weight. Three single nucleotide polymorphism (SNP) markers were also closely associated with fruit weight. Results from this study provide insights into the genetic and metabolic controls of fruit weight in loquat from multiple perspectives. The candidate genomic regions, genes, and sequence variants will facilitate our understanding of the molecular basis of fruit weight and lay a foundation for future breeding and manipulation of fruit weight in loquat.

[目的]了解枇杷不同组织中的萜类代谢物成分及含量,为高值化利用提供依据.[方法]利用超高效液相色谱-串联质谱(UPLC-MS/MS)广泛靶向代谢组学的方法,分析鉴定安徽大红袍枇杷叶片、花、果皮、果肉和种子等组织中的萜类代谢物成分,利用R软件进行主成分分析和聚类分析,比较不同组织中的萜类物质成分和含量差异.[结果]安徽大红袍枇杷叶片、花、果皮、果肉和种子等5个组织中,共鉴定出萜类代谢物51种,其中单萜1种、倍半萜1种、二萜3种、三萜42种、三萜皂苷4种,其中紫苏子醇、脱氢枞酸、白桦脂醇、脱氢山楂酸、23-羟基白桦脂酸等35种物质在枇杷中未见报道;各组织萜类代谢物分别为叶片50种、花49种、果皮49种、果肉45种、种子40种,所有组织共有成分38种,占51种萜类物质的74.5％.叶片、花、果皮、果肉和种子中萜类代谢物相对含量>1％的物质各有14、15、11、13、10种,各占其总萜类物质相对含量的88.46％、92.78％、92.37％、94.62％和96.28％,且以三萜类物质为主,5个组织共有的主要萜类物质有8种,分别为2α,19α-二羟基-3-氧熊果-12-烯-28-酸、科罗索酸、山楂酸、2-羟基齐墩果酸、2α,3α,23-三羟基齐墩果-12-烯-28-酸、蔷薇酸、积雪草酸、野蔷薇酸.聚类分析结果很好地展示了各组织萜类物质积累特征.[结论]枇杷叶、花、果皮、果肉和种子中的萜类物质种类丰富,叶片中的种类最多,其次是花和果皮,均以三萜类物质为主,新鉴定萜类物质35种,可供枇杷种质资源深度鉴定借鉴,也为枇杷叶、花和果的药用及其他高值化利用提供线索.

本研究采用两种方法提取'Marc'枇杷果肉中的萜类化合物,并利用超高效液相色谱-串联质谱技术分析鉴定提取物中的萜类化合物组分及峰面积.结果表明,方法一(无水乙醇+超声提取、浓缩+甲醇溶解+70％甲醇+涡旋)的提取物中鉴定到萜类化合物39种,方法二(70％甲醇+涡旋)的提取物中鉴定到萜类化合物15种;两者共有化合物相对含量也存在差异,方法一比方法二提取枇杷果肉萜类化合物的效果更好,且提取出的相对含量高出11.8～943.3倍.

Huataifeng (HTF) is an eminent cultivar selected from the crossing of Shixia and Xiangcui created and evaluated at National Longan Germplasm Nursery in Fuzhou, Fujian, China. Shixia is a prominent cultivar with high quality and fertility native to Guangdong, populous among Chinese cus-tomers. Xiangcui is a bud-mutation from Biew Khiew (a Thailand cultivar) with large fruit size and abundant fragrance. The hybrid was created in 2009 via artificial pollination, 148 seeds were gathered and consequently 112 seedlings were obtained. Line 09-1-70 (ultimately named HTF) was selected from the cross population for its early bearing capacity (fruiting initiated in 2012). Longan production suffered severe yield lose in Fujian province in 2013 due to off-year bearing, while HTF had a high flowering rate and yield as usual. The stable flower formation of this line might give rise to stable fruit production. It was then to top-grafted onto a mature longan tree in 2013. The grafted trees started to bear fruit in 2014, and from 2014 to 2017 all the grafted trees showed stable and consistent characteris-tic including high flesh recovery, high total soluble sugar content and abundant fragrance. Its fruit weight is 27.8%-48.2% higher than that of Shixia. From 2018 to 2021, HTF was the most consistent bearing line and showed no alternative bearing problem. Consequently, in 2021, HTF was certified in Fujian Province (no. 9352021Y0075). This cultivar has a strong growth vigor and a semi-open tree ar-chitecture. The bark is gray-brown and split into narrow rough ridges. Twigs are red-brown and smooth.The mature compound leaves are in size of (14.1-26.0) cm × (12.2-25.1) cm, and their 4-5 pairs of leaf-lets are green, lanceolate, and (12.8-18.7) cm × (3.9-4.7) cm in size. The leaf margins are wavy, and apex narrowly acuminate. The juvenile phase of 3 years of this cultivar is rather short. And it forms in-florescence every year. Its flower cluster is large and scattered. The oblate fruit are uniform in size with a blue-brown pericarp. The fruit base is flat, sometimes with one risen shoulder and the fruit tip is round. The skin segments are obvious. The fruit has an average longitudinal diameter of 2.73-2.81 cm, average transverse diameter of 2.89-2.93 cm, and average lateral diameter of 2.67-2.70 cm. The aril is milky, translucent, fragrant, tender and crisp, and can be easily separated from the seed. Average fruit weight is (12.7±1.0) g. The flesh recovery is (70.8±1.6)%, and TSS (22.7±2.8)%. HTF has an excellent grafting affinity to many main cultivars, such as Shixia and Chuliang (mainly cultivated in Guangdong province, Hainan province and Guangxi Autonomous Region), Fuyan, Songfengben, Lidongben (main-ly cultivated in Fujian province), and Shuguan, Lufeng (mainly cultivated in Sichuan province). The productivity of 7-year-old grafted trees can be up to 26.3 tons per ha (density 600). Bud breaking of HTF begins in late February, similar to that of Shixia, and the first leaf matured in late May. Inflores-cence morphological differentiation initiates in late February; flowers bloom from late April to early May, and ends in late May. The fruit matures during early September to early October in Fuzhou.

[目的]探讨枇杷种质资源不同组织中主要三萜酸组分含量多样性,为功能化利用与特异资源挖掘提供依据.[方法]利用高效液相色谱法测定10份枇杷种质叶片、果皮、果肉和种子中的熊果酸、科罗索酸、齐墩果酸等三萜酸组分含量,并进行多样性和相关性分析.[结果]10份枇杷资源的叶片、果皮、果肉、种子中均含有熊果酸、科罗索酸、齐墩果酸,各组织中的三萜酸组分含量变异系数为21.8％～213.4％,变异最小的是叶片齐墩果酸含量,变异最大的是果肉熊果酸含量.不同组织中,叶片的三萜酸含量最高,其熊果酸、科罗索酸、齐墩果酸和总三萜酸的平均含量分别为4.10、3.47、1.10、8.63mg·g-1,是果皮的1.8～2.2倍、果肉的64.1～582.2倍、种子的114.4～170.6倍.大多数资源叶片和果皮的熊果酸含量最高,平均熊果酸含量各占总三萜酸的47.5％和51.4％,其次是科罗索酸含量,各占40.2％和35.7％,齐墩果酸含量均最低;果肉中科罗索酸含量最高,占总三萜酸的75.6％～94.1％,熊果酸和齐墩果酸含量低.各组织中的熊果酸、科罗索酸与三萜酸总量均呈极显著正相关.[结论]枇杷种质资源各组织中的熊果酸、科罗索酸、齐墩果酸含量均存在丰富的多样性;叶片的三萜酸含量高于果皮,二者的含量远高于果肉和种子.研究结果可指导叶片高三萜酸种质挖掘,也可用于果皮高熊果酸或果肉高科罗索酸优异资源的挖掘.

枇杷是原产我国的常绿果树,果实春末夏初鲜果淡季应市,广受消费者青睐.2020年研究同行发布了首个枇杷参考基因组,昭示枇杷基础研究正式进入后基因组学时代.本文综述了2020年枇杷种质资源与新品种选育、栽培管理与生长发育调控、品质调控与采后保鲜、功能组分鉴定与新产品开发、生物与非生物胁迫响应等多个领域的研究进展,并展望了后基因组学和大数据时代枇杷若干领域的研究趋势.

利用SLAF-seq测序技术,开发一批特异性强、稳定性高的单核苷酸多态性(SNP)位点,为枇杷遗传图谱构建、分子辅助育种和物种进化等研究提供理论依据.本研究共收集294份枇杷属资源,利用SLAF-seq测序技术进行测序.以梨基因组为参考基因组进行电子酶切预测,确定使用HaeⅢ+Hpy166Ⅱ进行酶切,构建SLAF-seq文库,而后筛选314～364 bp长度的DNA片段定义为SLAF标签,预测可得到116 171个SLAF标签.共获得526.63 Mreads数据,各样品所获得的读长数目在119893～9305 152范围内,平均读长为1 787581;测序质量值Q30的范围在88.26％～95.67％,平均为93.61％;GC含量分布在38.79％～42.92％范围内,平均值为40.35％.本实验以水稻测序获得0.16 M reads的数据量为Control,双端比对效率在91.28％,说明SLAF建库基本正常.生物信息学分析结果显示本研究共获得623 356个SLAF标签,且有123 498个多态性的标签,多态性为19.81％.在多态性SLAF标签上开发得到1 604 434个群体SNP标记.根据完整度＞0.8,MAF＞0.05过滤,共得到95 960个高一致性的群体SNP.

本研究以龙眼早熟品种'石硖'、晚熟品种'香脆'与'立冬本'的4个不同发育阶段的果肉为试材,利用q-PCR技术对EF-1α-1、EF-1α-2、Actin1、Actin2及GAPDH2等5个候选内参基因的表达水平进行检测,并采用geNorm、NormFinder、BestKeeper和ReFinder软件综合分析评价其稳定性.结合应用验证,最终得出EF-1α-1、EF-1α-2和Actin2是龙眼果实发育q-PCR的适宜内参基因.