Fruit properties during the harvest period of eleven Indian jujube (Ziziphus mauritiana Lamk.) cultivars

The geometric attributes and physical, mechanical, and chemical properties were determined for 11 Indian jujube (Ziziphus mauritiana Lamk.) cultivars grown in Saudi Arabia including Zaytoni, Kashmiri, Komethry, Um-Sulaem with spines, Toffahy, Um-Sulaem without spines, Abdel-Sattar, Pu-Yun, Pu-Pineau, seedy ber, and buddling ber. The geometric mean diameter, surface area, sphericity, and shape index of the fruits ranged from 20.61 to 42.48 mm, 1339.58–5666.92 mm², 71.39–96.80%, and 110.25–275.18%, respectively. The fruit physical properties, i e fruit weight, fruit volume, stone weight, flesh weight, true fruit density, and pulp-stone ratio varied from 4.71 to 39.02 g, 4.78 to 42.75 cm3, 0.11 to 2.35 g, 4.61 to 36.67 g,0.913 to 1.055 g/cm3, and 7.90 to 43.11, respectively. In addition, the mean color value of L*, a* and b* for the fruits ranged from 64.48 to 96.33, 2.65–4.05, and 6.32–84.36, respectively. The mechanical properties, including elastic range, bioyield force, modulus of elasticity, plastic range, and rupture force ranged from 2.31 to 8.86 mm, 21.64–325.77 N, 14.15–124.09 N/s, 0.83–3.45 mm, 56.42–364.21 N, and 107.77–480.91 N/s, respectively. The greatest rupture force belonged to the Pu-Pineau cultivar and the smallest belonged to the Um-Sulaem without spines cultivar at the horizontal orientation of both cultivars. The fruit chemical analysis values for total soluble solids, titratable acidity, total soluble solids/titratable acidity ratio, and vitamin C ranged from 13.43 to 23.55%, 0.48–1.27%, 14.24–39.85%, and 55.27–164.47 mg/100 g, respectively. The relevant data obtained for the 11 varieties of Indian jujube are valuable for developing and designing machines for processing operations, transportation, separating, packing, sorting, and harvesting. Additionally, the findings revealed considerable variation in chemical content, physical and mechanical characteristics among the tested cultivars.     

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.     

Development and characterization of 38 polymorphic microsatellite markers from an economically important fruit tree, the Indian jujube

? Premise of the study: A total of 38 polymorphic microsatellite loci of the Indian jujube (Ziziphus mauritiana), an economically important fruit tree, were developed to evaluate genetic diversity and aid in the identification of cultivars. ? Methods and Results: The 38 microsatellite markers were isolated from the Indian jujube using a magnetic bead enrichment method, and polymorphisms were identified in 24 Indian jujube cultivars. The number of alleles ranged from two to 13, with expected heterozygosity ranging from 0.261 to 0.898. The polymorphism information content ranged from 0.248 to 0.889, with a mean of 0.616. Of these 38 simple sequence repeat loci, 20 loci from Z. jujuba (Chinese jujube) were successfully amplified using the simple sequence repeat primer sets. ? Conclusions: These polymorphic loci should be useful in further studies of the genetic diversity and the identification of cultivars of both the Indian jujube and the Chinese jujube.     

红枣贮藏期果面微生物功能多样性研究

摘要：【目的】了解果品微生物功能多样性信息,为红枣贮藏期贮藏病害的防控提供技术支撑,同时希望为果品果面微生物多样性的研究提供新的方法。【方法】采用Biolog方法研究了红枣贮藏期果品果面微生物群落结构功能多样性。【结果】红枣在不同贮藏时间内果面微生物群落的功能多样性差异很大,贮藏时间越长微生物越丰富,对不同碳源的利用程度越高;采用保鲜剂处理后红枣果面微生物群落的多样性、均匀度指数和AWCD 均显著低于未作任何处理的红枣果面微生物。四种不同处理的红枣果面微生物的特征碳源主要有六类：碳水化合物类、羧酸类、聚合     

红枣贮藏期果面微生物多样性

以2种成熟度不同的红枣(Zizyphus jujuba Mill.)为试验材料在入库前采用保鲜剂处理,未采用保鲜剂处理的红枣为试验对照,研究红枣不同贮藏时期果面微生物多样性。结果表明:红枣贮藏期果面微生物种群中,细菌是优势类群,占微生物总数80%以上,真菌较少;采摘期红枣果面上就携带微生物,真菌优势菌株属于链格孢(Alternaria),其次为镰刀菌(Fusarium)和木霉(Trichoderma),贮藏期优势菌株属于链格孢(Alternaria)、青霉(Penicillium)、木霉(Trichoderma)和镰刀菌(Fusarium),曲霉(Aspergillus)、毛霉(Mucor)和根霉(Rhizopus)次之。红枣贮藏期果面微生物种群动态失衡是导致贮藏病害发生的主要原因,成熟度较高的红枣果面微生物总数、真菌和细菌的数量明显高于成熟度较低的红枣,使用保鲜剂后有效地降低了红枣贮藏期果面微生物的多样性,贮藏时间越长红枣果面微生物的多样性越明显。     

Identification of anthocyanins in the fruits of Kadsura coccinea using UPLC-MS/MS-based metabolomics

Fruit color is thought to be an adaptation to different animal pollinators, the fruits of Kadsura coccinea present diverse colors but the metabolic mechanism of the differences in color still needs further clarification. Here, we performed ultra-performance liquid chromatography-tandem mass spectrometry based on targeted metabolome analysis of the fruits of two K. coccinea cultivars, ‘Dahong No. 1’ (red-peel) and ‘Jinhu’ (yellow-peel). A total of seventeen anthocyanins were identified in the fruit peels of ‘Dahong No. 1’, whereas no anthocyanins were detected in ‘Jinhu’. Our results suggest that the color differences between the two cultivars can be explained by variations in abundance of cyanidin 3-O-rutinoside, cyanidin 3-O-glucoside and delphinidin 3-O-glucoside, accounting for 91.64% of the content of total anthocyanins. This study provides new insights into the underlying metabolic causes of color variation in K. coccinea fruits, and thus provides a theoretical basis for the development and utilization of K. coccinea fruits in the future.     

Physiological and molecular analyses of early and late Coffea arabica cultivars at different stages of fruit ripening

Coffee quality is strongly influenced by a great number of factors, among which the fruit ripening stage at harvest time has a major influence on this feature. Studies comprising ethylene production and the regulation of ethylene biosynthesis genes during the ripening process indicate that ethylene plays an important role on coffee fruit ripening. Coffee early cultivars usually show a more uniform ripening process although little is known about the genetic factors that promote the earliness of ripening. Thus, in order to better understand the physiological and genetic factors involved in the regulation of ripening time, and consequently ripening uniformity, this study aimed to analyze ethylene and respiration patterns during coffee ripening, as well as to analyze ACC oxidase, an ethylene biosynthesis enzyme, gene expression, in fruits of early (Catucaí 785-15) and late (Acauã) coffee cultivars. Coffee fruits were harvested monthly from 124 days after flowering (end of February), until complete maturation (end of June). Dry matter, moisture content, color, respiratory rate and ethylene production analysis were performed. In silico analysis identified a coffee ACC oxidase gene (CaACO-like) and its expression was analyzed by real-time PCR. Dry matter and relative water content constantly increased and gradually decreased, respectively, during fruit ripening, and the color analysis enabled the observation of the earliness in the ripening process displayed by Catucaí 785-15 and its higher fruit ripening uniformity. The results obtained from the CaACO-like expression analysis and respiration and ethylene analysis suggest that the differences in ripening behavior between the two coffee cultivars analyzed in this study may be related to the differences in their capacity to produce ethylene, with fruits of Catucaí 785-15 and Acauã showing a typical and an attenuated climacteric phase, respectively, which may have lead to differences in their ripening time and uniformity.     

Survey of termite-inhabited soil and mosquito breeding sites in Lucknow,India for potential mycopathogens of Anopheles stephensi

A mycological survey was carried out on the fruit surface of Indian jujube during its growth period (before harvest). A total of 32 microfungi belonging to 20 genera were isolated by surface washing technique. Artificial inoculations with the isolated myco-propagules were also performed in mature jujube fruits and most of them were able to cause rot of varying severity. However, Monodictys castaneae, Eupenicillium lapidosum, Paecilomyces fumosoroseus, Trichurus spiralis and Acremonium spp., although present on the fruit surface, were not able to cause rot, indicating lack of specific macerating enzymes necessary for postharvest pathogenesis. This revised version was published online in June 2006 with corrections to the Cover Date.     

Accumulation of antioxidants in apricot fruit through ripening: characterization of a genotype with enhanced functional properties

Two apricot genotypes, 'Gonci magyarkajszi' and 'Preventa' were assayed at three ripening stages for flesh color indices (L*, a*, b*, C* and Ho), contents of total phenolics and vitamin C, and both water- and lipid-soluble antioxidant capacities (ferric reducing antioxidant power; 2,2'-diphenyl-1-picrylhydrazyl scavenging activity; total radical scavenging activity; and Photochem lipid-soluble antioxidant capacity) to compare their dynamics in the accumulation of antioxidant compounds and capacities through ripening. The increase in a*, b* and C* and decrease in Ho during ripening represented a color shift from green to yellow and orange due to carotenoid accumulation. Parallel to carotenoid accumulation, contents of total phenolics and vitamin C and antioxidant capacity increased significantly (p < 0.05) from unripe to fully ripe fruits. More phenolics and vitamin C accumulated in fully ripe fruits of 'Preventa' than 'G?nci magyarkajszi'. The accumulation patterns of these compounds were different: while the vitamin C contents in unripe fruit of 'Preventa' and 'G?nci magyarkajszi' were identical (approx. 6 mg/100 g fresh weight), unripe 'Preventa' contained even more phenolics (approx. 12 mmolGA/l) than fully ripe 'G?nci magyarkajszi' (8 mmolGA/l). Our results confirm that fully ripe 'Preventa' fruits are characterized by outstanding functional properties due to the increased accumulation of vitamin C and phenolics throughout the ripening process.     

Identification of genes associated with fruit ripening in Ziziphus jujuba using suppression subtractive hybridization approach

Owing to the high nutritional value and extensive medicinal use of its products, Chinese jujube (Ziziphus jujuba Mill) is one of the most important fruit crops in China. However, jujube fruits are highly perishable and thus have a short shelf life, which is a serious hindrance to the industry. Better understanding of the molecular mechanisms underlying jujube fruit softening is fundamental to overcome the problem. Thus, both forward and reverse suppression subtractive hybridization (SSH) cDNA libraries were constructed to identify differentially expressed genes for fruit at half-red ripening stage and complete red stage. As a result of dot blot confirmation, a total of 154 differentially expressed genes were identified. After removed low-quality regions and screened for vector contamination, blasted with the non-redundant NCBI databases, 78.6 % of sequences exhibited high homology to previously identified or putative proteins. All the ESTs were annotated and classified according to the terms of the three main Gene Ontology vocabularies using the Blast2GO software. Furthermore, the quantitative real-time PCR was carried out for 17 genes to validate the genes differentially expressed from the SSH libraries. And the full-length sequences of galactose oxidase and aldehyde dehydrogenase genes were obtained. It is the first step to explore the functional genomics and regulatory networks during the storage period of jujube fruit. The identification of the genes differentially expressed is helpful to understand the ripening and softening of the jujube fruit at the molecular level.     

Identification of two Bacillus amyloliquefaciens strains with high suppression to the key fruit pathogens of Chinese jujube

Two bacterial strains (ZJ01 and ZJ02) isolated from the phyllosphere of Chinese jujube were tested for antifungal activities and morphological mechanisms against Phoma destructiva, Alternaria alternata and Fusicoccum spp., three key pathogens of jujube fruits. Based on their physiological characteristics and 16S rDNA gene sequences, both strains were identified as Bacillus amyloliquefaciens. The disease incidence of jujube fruits sprayed with the fermentation liquor of ZJ01 and ZJ02 on the puncture wounds before inoculation with the spores of those three key pathogenic fungi was 10% or 66.7%, significantly lower than that of Nutrient Broth medium treatment (100%). These results suggest that strains ZJ01 may be a potential biological control agent for Chinese jujube fruit diseases. The antagonistic bacteria could cause five kinds of hyphal alterations of the causal agents, the maximum number ever observed. Of them, hyphal swelling and excessive branching were the dominant phenomenon, the other three varied with the pathogens. The diverse morphological malformation might be helpful to understand the broad antifungal activity of Bacillus spp..     

Effect of an Antagonistic Yeast in Combination with Microwave Treatment on Postharvest Blue Mould Rot of Jujube Fruit

The potential of using an antagonistic yeast alone or in combination with microwave treatment for controlling blue mould rot of jujube fruit, and its effect on postharvest quality of fruit, was investigated. The results showed that the growth of Penicillium citrinum was completely inhibited by a 2450‐MHz microwave heating for 2 or more minutes in vitro. The population density of P. citrinum in surface wounds of fruit treated with microwave treatment for 2–3 min was significantly lower than that of controls. When tested on jujube fruit, antagonistic yeast or microwave treatment, as stand‐alone treatment, the disease incidence of infected wounds was reduced from 100% to 45.0% and 36.0%, and lesion diameters were reduced from 1.92 cm to 1.50 cm and 1.38 cm, respectively. However, in fruit treated with a combination of Metschnikowia pulcherrima and microwave treatment, the disease incidence of infected wounds and lesion diameters was only 21.0% and 1.00 cm, respectively. The natural decay incidence on jujube fruit treated with the combination of microwave treatment and M. pulcherrima was 6.2% after storage at 2 ± 1°C for 45 days and at 22°C for 7 days. None of the treatments impaired quality parameters of fruits. Thus, the combination of microwave treatment and M. pulcherrima could provide an alternative to synthetic fungicides for controlling postharvest blue mould rot of jujube fruit.     

Egg adhesion of the codling moth Cydia pomonella L. (Lepidoptera,Tortricidae) to various substrates: II. Fruit surfaces of different apple cultivars

In the late growing season of apples, most eggs of the codling moth, Cydia pomonella L. (Lepidoptera, Tortricidae), of the second and third generations are deposited directly on fruits. The apple fruit surface is densely covered by three-dimensional micro- and nanoprojections, the epicuticular wax crystals, emerging from an underlying wax film. These epicuticular waxes render the apple fruit surface hydrophobic, which could affect the attachment of insect legs and eggs to it. A better survival of the codling moth offspring is expected to be ensured by the selection of suitable oviposition sites by females, as well as by a proper adhesion of deposited eggs to these sites. In this study, we investigated egg adhesion of the codling moth to the fruit surface of different cultivars of the domestic apple, Malus domestica Borkh., by measuring the pull-off force required to detach eggs from fruits. Since surface characteristics may influence insect egg adhesion, the information about morphological and physicochemical properties of the fruit surface is crucial for understanding oviposition site selection by females. In the present study, surface morphology, wettability, and free surface energy of the apple cultivars ‘Boskoop’, ‘Elstar’, ‘Golden Delicious’, ‘Jonica’, and ‘Topaz’ were analyzed. Eggs adhered tightly to the fruit surface of all apple cultivars tested: pull-off forces averaged 63.9 mN. These forces are four- to tenfold stronger than those previously measured on adaxial and abaxial leaf surfaces of the identical apple cultivars. The mechanisms used by the moth to fix its eggs on the waxy surface of apple fruits, and the influence of fruit surface properties on egg glue adhesion are discussed. Furthermore, the results are debated in the context of the oviposition site selection by females, and its role in offspring survival of the second and third generations of the codling moth.     

Fruit choice by red howler monkeys (Alouatta seniculus) in a tropical rain forest

This paper presents and discusses aspects of fruit selectivity by red howler monkeys (Alouatta seniculus) in relation with morphological characteristics of fruits. These data are used to provide an answer to the following questions: which are the fruit characteristics that lead fruit choice of howler monkeys and to what extent fruit characteristics play a role in seed dispersal by monkeys? The frugivorous diet of a troop of red howler monkeys was determined during a 2-year field study in French Guiana. The selection of fruit by howler monkeys was analyzed in relation to the fruit availability. Results showed that, although consumption followed availability, fruit species could be classified in three categories according to their selection ratio (percentage of consumption/percentage of abundance) as “high ranking,” “middle ranking,” and “low ranking” species. Also, the 97 species of fruit eaten by the monkeys were grouped according to the morphological characteristics thought to influence the monkeys' choice. This showed that howler monkeys consumed essentially fruits with juicy pulp, bright color, and a small number of well-protected seeds. Most of high ranking species had medium-sized fruits with yellow color, and low ranking species often had small fruits. However, howler monkeys are associated with the dispersal of seeds from fruit with a hard and indehiscent pericarp and/or large seeds, like those of the Sapotaceae family. Consequently, they can be considered as “specialized” frugivores for this fruit syndrome. © l996 Wiley-Liss, Inc.     

植物果实、颜色和形状对橘小实蝇产卵选择的影响

橘小实蝇Bactrocera dorsalis(Hendel)是近几年入侵江苏南部地区,严重危害当地水果、蔬菜的重要害虫。为深入了解其在该地区果树、蔬菜上的产卵特性,进行植物果实、颜色和形状对其产卵选择影响的研究。实验室中"纸杯法"的产卵选择试验结果表明,橘小实蝇对不同水果的产卵偏好性由高到低依次为:柑橘、香蕉、芒果、枣、石榴、苹果、桃子、梨、李、葡萄、柿;对不同蔬菜的产卵偏好性由高到低依次为:丝瓜、豇豆、苦瓜、黄瓜、茄子、南瓜、青椒、番茄。对不同寄主颜色和形状的产卵选择特点为,雌虫常选择桔黄色、绿色,以及圆球形的寄主产卵,而较少选择黑色、方形的寄主产卵。从试验结果可以看出,寄主果实散发出的气味,及其颜色和形状对橘小实蝇的产卵选择有影响。     

Cloning of FaPAL6 gene from strawberry fruit and characterization of its expression and enzymatic activity in two cultivars with different anthocyanin accumulation

The accumulation of anthocyanin pigments is one of the most important traits that turn strawberry fruit attractive to consumers. During ripening, strawberry fruit color development is associated to anthocyanin synthesis through the phenylpropanoid pathway. Phenylalanine ammonia-lyase (PAL) is a key enzyme in this pathway, having a determining role in strawberry fruit quality. In this work, we studied the level of anthocyanins during fruit ripening of two cultivars that differ in color development (Camarosa and Toyonoka). Toyonoka showed a lower anthocyanin accumulation that was limited to external fruit tissue, while Camarosa accumulated higher amount of anthocyanins in both internal and external sections. In addition, we cloned a full-length gene (FaPAL6) and analyzed its expression in different strawberry plant tissues. The expression of this gene is fruit specific, and increases during fruit ripening in both cultivars along with anthocyanin accumulation. The mRNA level of FaPAL6 was higher in Camarosa. PAL enzyme activity increased at similar rates in both cultivars at early ripening stages, but at the end of ripening PAL activity diminished in Toyonoka while it rose markedly in Camarosa. PAL activity was higher in internal fruit tissue, showing no correlation with anthocyanin level of the same section in both cultivars. The higher FaPAL6 expression and activity detected in Camarosa could be associated to the enhanced anthocyanin accumulation found in this cultivar.     

Contents of Sugars, Fruit Acids, Amino Acids and Phenolic Compounds of Apple Fruits i n Relation to their Susceptibility to Botryosphaeria ribis

Five apple cultivars showing different levels of susceptibility to Botryosphaeria ribis were used to study the relationship between susceptibility and contents of sugars, fruit acids, amino acids and phenolic compounds in the fruits at various stages of maturity. Immature fruits of all the cultivars tested were completely resistant until 10 July. The fungus grew better on the yellow-coloured cultivars than the red-coloured cultivars. The low amount of reducing sugars and also the high levels of fruit acids, amino acids and total phenols were found in immature apple fruits, irrespective of cultivar. No consistent differences between the cultivars were recognized with regard to the contents of soluble sugars, fruit acids and phenols in fruit flesh during the maturity of fruits. However, only the levels of total soluble amino acids in fruit flesh and of total phenols in fruit peel at late stage of maturity consistently varied between the cultivars. The dark red-coloured, resistant cultivars Miller spur and Starkrimson showed higher contents of amino acids and phenols in fruit tissues than did the yellow-coloured, susceptible cultivars.