Jujube Cultivars Research Articles

Characterization of the Major Odor-Active Compounds in Dry Jujube Cultivars by Application of Gas Chromatography-Olfactometry and Odor Activity Value.

The volatile compounds of jujube ( Ziziphus jujube Mill.) puree obtained from three cultivars, 'Jinsixiaozao' (Y1), 'Youzao' (Y2), and 'Yuzao' (Y3), were analyzed by gas chromatography-olfactometry (GC-O), gas chromatography-mass spectrometry, gas chromatography-flame photometric detection, and a nitrogen phosphorus detector. The results showed that a total of 37, 37, and 35 odor-active compounds were identified by GC-O in samples of Y1, Y2, and Y3, respectively. In addition, the odor activity value (OAV) was used to determine the important compounds. The results demonstrated that hexanal (OAV of 39-85), ( E)-2-octenal (OAV of 32-70), β-damascenone (OAV of 14-49), ethyl hexanoate (OAV of 22-39), 3-mercaptohexyl acetate (OAV of 17-24), and 2,5-dimethylpyrazine (OAV of 17-22) were key odor-active compounds. It is of great significance to develop high-grade jujube food by determining key odor-active compounds. Furthermore, four volatiles (hexanal, 1-octen-3-ol, 3-mercapohexyl acetate, and benzaldehyde) reduced the overall threshold value by 2.36, 1.01, 1.34, and 1.19, respectively.

Bioactive, nutritional composition, heavy metal and pesticide residue of four Chinese jujube cultivars.

This study aims to conduct a detailed investigation on four cultivars grown in northwest China, concentrating on the analysis of the bioactive contents, nutrients, heavy metal concentrations, and pesticide residue contents. Those Chinese jujubes consist of 51.99-71.75% edible part, 82.35-89.63% carbohydrates, 4.43-6.01% protein, 0.48-0.63% lipid, 2.80-4.80% polysaccharide, 45.64-88.97mg/100g ascorbic acid, 132.16-196.58mg/100g phenolics and 101.17-132.04mg/100g flavonoids in dry matter. In those four Chinese jujube cultivars, sulfur amino acids are the first limiting amino acids for adults, and aromatic amino acids are for children. The amount of heavy metal and pesticide residue concentrations in those jujubes was way below the limit. All four cultivars were found to have different nutritional values except for the carbohydrates; they had higher rates of carbohydrates and polysaccharide than those previously reported ones from Eastern China; and they are a better source for carbohydrates, vitamin C and functional amino acids.

Jujube Phenology, Pollen Germination, and Two Unique Germplasm Resources in New Mexico

Jujube (Ziziphus jujuba Mill.) originated in China and grows well in a wide range of areas in the United States, especially the southwest. New Mexico State University’s Sustainable Agriculture Science Center has imported and collected over 50 jujube cultivars and conducted a series of jujube-related research projects. In this study, jujube phenology and pollen germination in New Mexico were investigated and two unique germplasm resources were reported. Jujubes leafed out 4–8 weeks later than most pome and stone fruits and bloomed 2–3 months later than apricots, peaches, and apples. It can avoid late frosts in most years in northern New Mexico and, thus, produce a crop more reliably than traditional fruit crops in the region. For the 48 cultivars tested for pollen germination, the germination rates ranged from 0% to 75% depending on the cultivar and year. ‘September Late’ had the highest pollen germination rate each year among all cultivars tested from 2012 to 2014, whereas ‘GA866’, ‘Maya’, and ‘Sherwood’ had the lowest. ‘Zaocuiwang’ was the first reported male-sterile jujube cultivar in the United States, and this character was consistent from year to year and, thus, it would be a valuable cultivar for jujube breeding. Cultivar Yu had pseudo-flowers which never bloomed or set fruit. It would be a useful germplasm as special landscape trees or for genomic study of jujube flowering-related genes.

ВЫЯВЛЕНИЕ ВЗАИМОСВЯЗИ МЕЖДУ ХОЗЯЙСТВЕННО-БИОЛОГИЧЕСКИМИ ПРИЗНАКАМИ ЗИЗИФУСА ДЛЯ ОПРЕДЕЛЕНИЯ КРИТЕРИЕВ МОДЕЛИ СОРТА

The modern gardening supposes introduction of cultivars that mostly meet market demands, soil and climatic conditions of their growing. The article covers study results of correlations between jujube economical, morphological and biological characters. 12 jujube cultivars were analyzed concerning similarity with the cultivar model. According to characters’ similarity and their significance, the studied cultivars are possible to unite into five clusters. By complex of parameters the closest cultivars to the model are Koktebel (170 units of Euclidean distance), Yalita, Ta-Yan-Tsao (82 units of Euclidean distance), Sinit, Yuzhanin (80 units of Euclidean distance).

Impacts of Brassinolide on the Photosynthetic Characteristics of 'Qiyuexian' Jujube

The jujube cultivar ‘Qiyuexian’ was chosen as object in this study. Effects of different concentrations of brassinolide (BL) on its characteristic parameters of light/CO 2 response curve were investigated. The results indicated that the mentioned parameters were significantly affected by the concentrations of BL. The Light Saturation Point ( LSP ) was significantly increased by 17.42% after being treated by 0.1 mg/L BL. After spraying 0.2 mg/L BL, the maximum net photosynthetic rate ( Pnmax ), apparent quantum efficiency ( AQY ), LSP, maximum carboxylation rate ( V cmax ), maximum rate of photosynthetic electron transport ( J max ) and Triose Phosphate Utilization rate ( TPU ) were significantly increased by 21.14, 20.26, 21.95, 21.14, 20.26 and 21.95%, respectively. The AQY , LCP , LSP , V cmax and J max were significantly increased by 12.55, 60.75, 19.00, 20.96 and 20.06% respectively after being treated by 0.3 mg/L BL, while the LCP and LSP were significantly increased by 65.53% and 25.79% respectively after being treated by 0.4 mg/L BL. In conclusion, 0.2 mg/L BL treatment could significantly accelerate the overall photosynthetic ability of “Qiyuexian” jujube, promoting its accumulation of assimilative products, which is beneficial to increase the production and quality of jujube fruits.

Optimisation of a highly efficient shoot regeneration system using leaf explants of Chinese jujube (Ziziphus jujuba Mill.) by response surface methodology

ABSTRACTChinese jujube (Ziziphus jujuba Mill.) is a major fruit crop in Asia. In this study, response surface methodology (RSM) was successfully employed to establish a highly efficient in vitro propagation and regeneration system for the ‘Teapot’ jujube via shoot organogenesis. Among the tested factors, gibberellic acid (GA3) concentration showed the most significant positive effect. The pre-culture darkness timing and medium were also important factors for highly efficient shoot regeneration of the ‘Teapot’ jujube. The highest regeneration (> 75%) was achieved by 1 week in darkness and culture on wood plant medium (WPM) containing 0.25 mg·L−1 GA3, 0.5 mg·L−1 6-benzylaminopurine (BAP) and 0.1 mg·L−1 3-indoleacetic acid (IAA). In vitro-derived shoots rooted very well in the modified 1/2 Murashige and Skoog (MS) medium containing 0.4 mg·L−1 3-indolebutyric acid (IBA), resulting in a 100% rooting rate. These findings suggest that the RSM can be employed to optimise the protocols needed for successful in vitro plant regeneration of jujube cultivars, with potential applications in plant genetic transformation practices, polyploidy induction and germplasm preservation.

Jujube Cultivar Vitamin C Profile and Nutrient Dynamics during Maturation

Vitamin C profiles of 46 jujube cultivars were assessed from 2012 to 2015, and fruit nutrient dynamics of 10 cultivars during maturation were examined from 25 Aug. to 7 Oct. 2014 at 2-week intervals at New Mexico State University’s Alcalde Sustainable Agriculture Science Center and Los Lunas Agricultural Science Center. This is the first report in the United States profiling Vitamin C in jujube cultivars. The vitamin C content of mature fruit of 45 (of 46) cultivars ranged from 225 to 530 mg/100 g fresh weight (FW) plus ‘Youzao’ having the highest content of 820 mg/100 g FW at early mature stage. In general, drying cultivars had higher vitamin C content than fresh-eating cultivars whereas ‘Jinsi’ series (multipurpose) had relatively higher vitamin C content than others (>400 mg/100 g FW). Fruit vitamin C and moisture content decreased significantly during the maturation process. The average vitamin C contents of nine cultivars at Alcalde decreased more than 40% based on FW from 25 Aug. to 7 Oct. To maximize the vitamin C benefit, the ideal stage to consume fresh-eating cultivars is the creamy stage. Titratable acidity and soluble solids increased significantly during maturation. In mature jujubes, the titratable acidity and soluble solids ranged between 0.27% to 0.46% and 27.2% to 33.7%, respectively. Glucose, fructose, and sucrose content also rose significantly during ripening. Mature fruits contained 31–82 mg/g FW glucose, 32–101 mg/g FW fructose, and 53–159 mg/g FW sucrose among the cultivars tested. Based on sucrose contents, cultivars can be divided into two groups, “high-sucrose” (more sucrose than glucose or fructose) and “low-sucrose” (less sucrose than glucose or fructose). ‘Dagua’, ‘Honeyjar’, ‘Lang’, ‘Li’, ‘Maya’, ‘Sugarcane’, and ‘Sherwood’ belong to the “high-sucrose” group. Total phenolic content and 2,2-diphenyl-1-picrylhydrazyl (DPPH)-reducing capacity in fruit decreased during maturation, and the total phenolic content of mature jujube was 12–16 mg gallic acid equivalent (GAE)/g dry weight (DW). For mature fruit, ‘Li’ and ‘Li-2’ had the highest DPPH-scavenging efficiency whereas ‘Sugarcane’, ‘So’, and ‘Lang’ had the lowest at Alcalde, NM.

Genetic diversity of Indian jujube cultivars using SCoT, ISSR, and rDNA markers

Genetic variation and relationships among 37 cultivars of Ziziphus mauritiana (Lamk.) native of India were analyzed using start codon targeted (SCoT), inter-simple sequence repeats (ISSR), and ribosomal DNA (rDNA) markers. High level of polymorphism among SCoT (61.6%) and ISSR (61%) primers with higher PIC values ranging from 63.1 to 90.4% of SCoT and 47.3 to 88.8% of ISSR primers was recorded. SCoT and ISSR dendrograms revealed similarity coefficients ranging from 0.80 to 0.92 and 0.79 to 0.96, respectively, and clearly delineated all the cultivars of Z. mauritiana into well-supported distinct clusters. Greater Gst signifies higher amount of differentiation observed over multiple loci among seven Z. mauritiana populations. On the other hand, higher gene flow demonstrating a very high migration rate between Z. mauritiana populations indicated higher rates of transfer of alleles or genes from one population to another. The genetic diversity of population 1 (Rajasthan) was the richest among all the seven populations. The largest genetic distance was measured between Maharashtra and West Bengal and the least between Rajasthan and Punjab cultivars. Most of the genetic diversity exists within population rather than among populations. Substantial variation in the ITS-1 region signifies its phylogenetic utility specifically in assessing genetic diversity in Z. mauritiana. The clustering patterns using three molecular marker systems vis-a-vis place of origin exhibited no consistency in grouping of Z. mauritiana cultivars as cultivars from the same place of origin were genetically cataloged into different SCoT, ISSR, and ITS phylogram clusters indicating wide genetic diversity and distribution across agro-climatic zones validating the robustness of marker systems tested.

The Jujube Genome Provides Insights into Genome Evolution and the Domestication of Sweetness/Acidity Taste in Fruit Trees.

Jujube (Ziziphus jujuba Mill.) belongs to the Rhamnaceae family and is a popular fruit tree species with immense economic and nutritional value. Here, we report a draft genome of the dry jujube cultivar ‘Junzao’ and the genome resequencing of 31 geographically diverse accessions of cultivated and wild jujubes (Ziziphus jujuba var. spinosa). Comparative analysis revealed that the genome of ‘Dongzao’, a fresh jujube, was ~86.5 Mb larger than that of the ‘Junzao’, partially due to the recent insertions of transposable elements in the ‘Dongzao’ genome. We constructed eight proto-chromosomes of the common ancestor of Rhamnaceae and Rosaceae, two sister families in the order Rosales, and elucidated the evolutionary processes that have shaped the genome structures of modern jujubes. Population structure analysis revealed the complex genetic background of jujubes resulting from extensive hybridizations between jujube and its wild relatives. Notably, several key genes that control fruit organic acid metabolism and sugar content were identified in the selective sweep regions. We also identified S-locus genes controlling gametophytic self-incompatibility and investigated haplotype patterns of the S locus in the jujube genomes, which would provide a guideline for parent selection for jujube crossbreeding. This study provides valuable genomic resources for jujube improvement, and offers insights into jujube genome evolution and its population structure and domestication.

Free Sugar and Organic Acid Content of the Unripe and Ripe Jujube (Zyziphus jujuba) as Honey Plant

The fruit of five cultivars (Mudeung, Geumseong, Wolchul, Bokjo and Boeun) of jujube (Zyziphus jujuba) were analyzed to estimate free sugar and organic acid content in unripe and ripe jujube cultivars. Glucose, galactose, fructose and sucrose were the major sugar components of jujube. In this study, we observed that sucrose, glucose and fructose content increased during fruit ripening. The highest sucrose content of jujube fruit was 20.54g/100g in ripe Wolchul cultivar. The sweetness index, which plays important role of taste, was also calculated from the content of sucrose, glucose and fructose. The sweetness of jujube fruit increased with fruit growth and development. The highest sweetness of jujube fruit was 116.32 in ripe Geumseong cultivar. Main organic acid detected in jujube were citric acid, malic acid and fumaric acid. As the weight, diameter and soluble solids of Zyziphus jujuba fruit were increased with the progress of ripening, organic acids were also increased. The highest citric acid and malic acid content in jujube fruit were 14.64g/100g (Boeun, ripe) and 19.33g/100g (Geumseong, ripe), respectively.

대추(Zyziphus jujuba) 품종별 성숙정도에 따른 항산화 활성, 총페놀 함량, 비타민 C 함량 및 당함량

대추(Zyziphus jujuba) 품종별 성숙정도에 따른 항산화 활성, 총페놀 함량, 비타민 C 함량 및 당함량

Jujube (Ziziphus jujuba) in the United States: challenges and opportunities

Jujube cultivars were first introduced into the United States in 1908. Budwoods of over 30 cultivars were imported from 1908 to 1918. Unfortunately, most of them were lost after the USDA Chico Introduction Station was closed in the 1950s. Researchers working with jujubes predicted its high potential, especially in the Southwestern United States. So far, jujube-related research is very limited. Jujubes are distributed widely in the U.S., from Pennsylvania and Washington D.C. to Florida; and from Florida and Georgia, westward through Arkansas, Texas, and New Mexico out to California. They adapt well to the climate and soil conditions in the Southwest and fruit well. Commercial production is limited, but interest is growing. Nurseries have not been able to meet the market demands in recent years, and only a few cultivars are commercially available. Both growers and consumers demand more cultivar selections to extend the season and to satisfy different uses from consumers. With jujubes' late-spring start-up, they are also a good alternative crop in areas that suffer late-spring frosts. Because more consumers are concerned about the health benefits of fruit, jujubes are gaining attention again. Also, the Asian population is growing fast, especially near big cities, and their demand for jujubes is high. Researchers need to introduce and evaluate jujube cultivars and recommend more cultivars with varied maturity dates and uses to growers and consumers. More American-style jujube products are another key factor in promoting jujubes. With its nutritious fruit, wide adaption, early fruiting, and drought tolerance, jujube production could become an industry in the U.S. within 15-20 years.

Selection of Chinese jujube cultivars for juice processing based on theory of satisfaction and multidimensional matrix

Selection of Chinese jujube cultivars for juice processing based on theory of satisfaction and multidimensional matrix

Study on the fruit storage characteristics of different local jujube cultivars in Hunan province

Study on the fruit storage characteristics of different local jujube cultivars in Hunan province

Physico-chemical and physiological changes during fruit development and on-tree ripening of two Spanish jujube cultivars (Ziziphus jujuba Mill.)

Few studies have been performed on changes in organoleptic, nutritive, functional, and physiological properties during jujube fruit development and on-tree ripening. In this work, a comparative study on the evolution of physical, chemical, nutritive, and physiological parameters and bioactive compounds of two Spanish jujube cultivars was performed. Both cultivars showed a non-climacteric ripening pattern, although the JM cultivar was smaller, sweeter, softer, and more highly coloured than the JG, which was characterised by having larger and firmer fruits, although less sweet and coloured. Both cultivars showed high TAA, which was highly correlated with the concentration of total phenols, giving them great functional properties. This fruit has little economic importance in Spain and it is just marginally grown for self-consumption or for ornamental purposes. Given the excellent properties of these fruits, it could be considered a fruit species of great interest, and commercial growth of these cultivars with high yields and fruits with high functional properties should be promoted. © 2016 Society of Chemical Industry.

Characterization of SSR genomic abundance and identification of SSR markers for population genetics in Chinese jujube (Ziziphus jujuba Mill.).

Chinese jujube (Ziziphus jujuba Mill. [Rhamnaceae]), native to China, is a major dried fruit crop in Asia. Although many simple sequence repeat (SSR) markers are available for phylogenetic analysis of jujube cultivars, few of these are validated on the level of jujube populations. In this study, we first examined the abundance of jujube SSRs with repeated unit lengths of 1–6 base pairs, and compared their distribution with those in Arabidopsis thaliana. We identified 280,596 SSRs in the assembled genome of jujube. The density of SSRs in jujube was 872.60 loci/Mb, which was much higher than in A. thaliana (221.78 loci/Mb). (A+ T)-rich repeats were dominant in the jujube genome. We then randomly selected 100 SSRs in the jujube genome with long repeats and used them to successfully design 70 primer pairs. After screening using a series of criteria, a set of 20 fluorescently labeled primer pairs was further selected and screened for polymorphisms among three jujube populations. The average number of alleles per locus was 12.8. Among the three populations, mean observed and expected heterozygosities ranged from 0.858 to 0.967 and 0.578 to 0.844, respectively. After testing in three populations, all SSRs loci were in Hardy-Weinberg equilibrium (HWE) in at least one population. Finally, removing high null allele frequency loci and linked loci, a set of 17 unlinked loci was in HWE. These markers will facilitate the study of jujube genetic structure and help elucidate the evolutionary history of this important fruit crop.

Phenolic composition, ascorbic acid content, and antioxidant capacity of Spanish jujube (Ziziphus jujube Mill.) fruits

The interest in Ziziphus jujube is growing because it is an excellent source of nutrients and phytochemicals, and can contribute to a healthy diet. Nutritional compounds (phenolic compounds and l-ascorbic acid), and antioxidant capacity of 4 Spanish jujube cultivars were studied. Polyphenols were identified by LC–MS–QTof and quantified by UPLC–PDA–FL. A total of 25 polyphenolic compounds were identified and classified as 10 flavan-3-ols, 13 flavonols, 1 flavanone, and 1 dihydrochalcone. The content of total polyphenols (TP) ranged from 1442 to 3432mg/100g dry matter (dm) in fruits of the cultivars ‘DAT’ and ‘PSI’, respectively. Flavan-3-ols, the major group of polyphenols in jujube represented ∼92% of the TP content, whereas flavonols only amounted for about ∼8% each. The content of l-ascorbic acid was very high and took values in the range of 387–555mg/100g fresh weight (fw). Some Spanish jujube cultivars, especially ‘PSI’ and ‘MSI’, may be selected to promote the growth of cultivars with valuable nutritional and phytochemical beneficial effects on human health.

Estimation of Bioactive Compound, Maslinic Acid by HPTLC, and Evaluation of Hepatoprotective Activity on Fruit Pulp of Ziziphus jujuba Mill. Cultivars in India.

Fruits of Ziziphus jujuba Mill. (family: Rhamnaceae), known as Indian jujube or “Ber,” are of potential nutritional and medicinal value. The objectives of the present study were to estimate bioactive compound maslinic acid by HPTLC method and to evaluate in vitro antioxidant and hepatoprotective activity of eight cultivars of Indian jujube. Maslinic acid and the fruit pulp of various cultivars of Indian jujube, namely, Gola, Sannur, Umaran, Mehrun, and Chhuhara, exhibited significantly high antioxidant and hepatoprotective activity. HPTLC-densitometric method was developed for quantification of maslinic acid from fruits of Indian jujube cultivars. The trend of occurrence of maslinic acid in fruits pulp extracts was as follows: Gola > Sannur > Umaran > Mehrun > Chhuhara > Wild > Kadaka > Apple. A significant correlation was shown by maslinic acid content and prevention of oxidative stress induced by CCl4 in liver slice culture cell treated with extract. Maslinic acid along with its other phytoconstituents like phenols, flavonoids, and ascorbic acid may act as a possible therapeutic agent for preventing hepatotoxicity caused by oxidative stress generated due to the prooxidants like CCl4. This is the first report of fruit pulp extracts of Z. jujube cultivars in India and maslinic acid preventing CCl4 induced damage in liver slice culture cell of mice.

Flowering Characteristics and Honeybee Visiting of Jujube (Ziziphus jujuba Mill)

밀원수종으로서 대추나무의 특성을 구명하고자 수원지역에 식재된 국 · 내외 22품종에 대하여 개화특성, 화분 분비 및 꿀벌 방화를 조사하였다. 대부분의 품종들은 6월초 개화를 시작하여 평균 40일 이상 개화하였다. 개화 시간은 품종에 따라서 차이를 보여 오전 개화성 품종과 오후 개화성 품종으로 나뉘었다. 오전 개화성 품종의 경우 꿀벌의 방화는 오전 10시경에 가장 많았으며, 기온이 높고 습도가 낮은 오후 1시에서 4시 사이에 가장 적게 나타났다.

Development of Chloroplast Microsatellite Markers and Analysis of Chloroplast Diversity in Chinese Jujube (Ziziphus jujuba Mill.) and Wild Jujube (Ziziphus acidojujuba Mill.).

Ziziphus is an important genus within the family Rhamnaceae. This genus includes several important fruit tree species that are widely planted in China and India, such as the Chinese jujube (Ziziphus jujuba Mill.), the wild jujube (Z. acidojujuba), and the Indian jujube (Z. mauritiana). However, information about their domestication based on the chlorotype diversity of Chinese jujube population is lacking. In this study, chloroplast microsatellite (cpSSR) markers were developed and used to investigate the genetic relationships between and domestication of jujube cultivars and wild jujube populations. Primer sets flanking each of the 46 cpSSR loci in non-coding regions of the chloroplast genome sequence of Z. jujuba Mill. cv. ‘Junzao’ were designed. In total, 10 markers showed polymorphisms from 15 samples (9 jujube cultivars and 6 wild jujube individuals), of which 8 loci were due to variations in the number of mononucleotide (A/T) repeats and 2 were due to indels. Six cpSSR markers were used in further analyses of 81 additional samples (63 jujube cultivars, 17 wild jujube samples, and 1 Indian jujube). Using these cpSSR markers, the number of alleles per locus ranged from two to four. In general, the Shannon Index (I) for each cpSSR ranged from 0.159 to 0.1747, and the diversity indices (h) and uh were 0.061 to 0.435 and 0.062 to 0.439, respectively. Seven chlorotypes were found; the Indian jujube showed distinct chlorotypes, and both the Chinese and wild jujube had four chlorotypes and shared two chlorotypes. A dominant chlorotype (G) accounted for 53 of 72 jujube cultivars and 13 of 23 wild jujube individuals. All chlorotypes were highly localized along the Yellow River, from the mid- to the lower reaches, suggesting a wide origin of jujube. These cpSSR markers can be applied to population and evolution studies of Chinese jujube and wild jujube.