Arguta Var Research Articles

An effective method for establishing a regeneration and genetic transformation system for Actinidia arguta.

The all-red A. arguta (Actinidia arguta) is an anthocyanin-rich and excellent hardy fruit. Many studies have focused on the green-fleshed A. arguta, and fewer studies have been conducted on the all-red A. arguta. Here we reported a regeneration and Agrobacterium-mediated transformation protocol by using leaves of all-red A. arguta as explants. Aseptic seedling leaves of A. arguta were used as callus-inducing materials. MS medium supplemented with 0.3 mg·L-1 2,4-D and 1.0 mg·L-1 BA was the optimal medium for callus induction of leaves, and medium supplemented with 3 mg·L-1 tZ and 0.5 mg·L-1 IAA was optimal for adventitious shoot regeneration. The best proliferation medium for adventitious buds was MS + 1.0 mg·L-1 BA + 0.3 mg·L-1 NAA. The best rooting medium was 1/2MS + 0.7 mg·L-1 IBA with a 100% rooting rate. For the red flesh hardy kiwi variety 'Purpurna Saduwa' (A. arguta var. purpurea), leaves are receptors for Agrobacterium (EHA105)-mediated transformation. The orthogonal experiment was used for the optimization of each genetic transformation parameter and the genetic transformation of the leaves was 21% under optimal conditions. Our study provides technical parameters for applying genetic resources and molecular breeding of kiwifruit with red flesh.

De Novo Assembly of a Sarcocarp Transcriptome Set Identifies AaMYB1 as a Regulator of Anthocyanin Biosynthesis in Actinidia arguta var. purpurea.

The kiwifruit (Actinidia arguta var. purpurea) produces oval shaped fruits containing a slightly green or mauve outer exocarp and a purple-flesh endocarp with rows of tiny black seeds. The flesh color of the fruit results from a range of anthocyanin compounds, and is an important trait for kiwifruit consumers. To elucidate the molecular mechanisms involved in anthocyanin biosynthesis of the sarcocarp during A. arguta fruit development, de novo assembly and transcriptomic profile analyses were performed. Based on significant Gene Ontology (GO) biological terms, differentially expressed genes were identified in flavonoid biosynthetic and metabolic processes, pigment biosynthesis, carbohydrate metabolic processes, and amino acid metabolic processes. The genes closely related to anthocyanin biosynthesis, such as phenylalanine ammonia-lyase (PAL), chalcone synthase (CHS), and anthocyanidin synthase (ANS), displayed significant up-regulation during fruit development according to the transcriptomic data, which was further confirmed by qRT-PCR. Meanwhile, a series of transcription factor genes were identified among the DEGs. Through a correlation analysis. AaMYB1 was found to be significantly correlated with key genes of anthocyanin biosynthesis, especially with CHS. Through a transient expression assay, AaMYB1 induced anthocyanin accumulation in tobacco leaves. These data provide an important basis for exploring the related mechanisms of sarcocarp anthocyanin biosynthesis in A. arguta. This study will provide a strong foundation for functional studies on A. arguta and will facilitate improved breeding of A. arguta fruit.

Transcriptomic and metabolomics of flavonoid compounds in Actinidia arguta var. arguta

Actinidia arguta (Sieb. et Zucc.) Planch ex Miq. is fruit plant with high added value, rich in bioactive compounds relevant for human health, like flavonoids and vitamin C, and has high antioxidant activity. These flavonoids also play important roles in plant immune responses and have strong medicinal implications. Moreover, it is very widely distributed in China and attracted more attention with great economic significance in recent years. However, the majority of research on flavonoids has been focused on fruit, not much has been elucidated in leaf in A. arguta. Whether are the leaves of Actinidia arguta also rich in flavonoids and other biologically active ingredients? The metabolome and transcriptome in fruits and leaves of A. arguta var. arguta cv. Changjiang No.1 (CJ-1) was analyzed in this study. We detected ten flavonoids in CJ-1 leaves that belonged to quercetin, isorhamnetin and kaempferol and using LC-MS/MS technology. Flavonoid quercetin were all detected in five tissues. Flavonoid qualification indicated that total flavonoids in young apical leaves were the highest (10219.84 µg·g−1) and 129.8 folds than in fruits (78.75 µg·g−1). From the transcriptome data, we obtained 70,631 non-redundant unigenes in total. There were 32,593 differentially expressed genes (DEGs) to be identified, including 29,617 up-regulated and 2976 down-regulated genes in fruits and young apical leaves. There were 127 metabolic pathways enriched with 3567 DEGs, in which 45 DEGs were associated with flavonoid biosynthesis. Next, the expression of qRT-PCR of key flavonoid pathway genes in leaves were higher than that in other tissues, which was consistent with the higher total flavonoid level. The data provided here were valuable for knowing the molecular mechanisms of flavonoids accumulating in different tissues. Our results were of significant contribution to the literature as they proposed possible new insights of applying leaves in A. arguta in the food and healthcare industries for their high content of flavonoids.

The complete chloroplast genome sequence of Actinidia arguta var. giraldii

The complete chloroplast (cp) genome sequence of Actinidia arguta var. giraldii (Diels) Vorosch. was assembled and characterized by Illumina pair-end sequencing date. The complete plastid genome was 156,729 bp in length, containing a large single-copy (LSC) of 89,647 bp, and a small single-copy (SSC) of 22,482 bp, which was separated by a pair of 22,300 bp inverted repeat regions (IR). A total of 131 unique genes were identified, including 84 protein-coding genes, 39 tRNA genes, and 8 rRNA genes. The phylogenetic position based on the chloroplast genome of 11 species showed that A. arguta var. giraldii was sister to Actinidia kolomikta.

The Influence of Osmotic Dehydration Conditions on Drying Kinetics and Total Carotenoid Content of Kiwiberry (Actinidia Arguta)

AbstractKiwiberries (Actinidia arguta var. Geneva) were osmotically dehydrated in sucrose, xylitol and maltitol 60 % water solutions at 30 and 50 °C. After pre-treatment, the samples were dried using convective method at 70 °C until fruits have reached a dimensionless moisture ratio (MR) of 0.02. Osmotic pre-treatment significantly improved drying kinetics during the first stage of the process. All the pre-treated samples reached water activity level (aw) less than 0.6 after 7 h of drying. When maltitol or xylitol was used as an osmotic agent at 30 °C, the time required for drying was reduced by 23 and 32 %, respectively. In turn, dehydration performed at 50 °C had no positive effect on the drying kinetics. The shortest drying time was obtained for the samples dehydrated in xylitol at 30 °C. In the case of these samples target MR was reached after 542 min whereas in the case of untreated samples drying lasted 810 min. The highest retention of carotenoid was observed for the samples osmotically pre-treated in maltitol solution at 30 °C and sucrose solution at 50 °C.

The choice of female or male parent affects some biochemical characteristics of fruit or seed of kiwiberry (Actinidia arguta)

Kiwiberry (Actinidia arguta) is dioecious species which is now commercially grown in several countries worldwide. A study was conducted to determine the influence of five pollen sources derived from A. arguta (three cultivars), A. arguta var. purpurea ‘Rot’ and A. chinensis var. deliciosa ‘Tomuri’ on fruit and seed characteristics for three female A. arguta cultivars. Average fruit weight and biochemical features—fruit total phenolic concentration (TPC), ascorbate (ASC), pigments, total antioxidant activity and seed proteins profile were evaluated. TPC was determined using the Folin–Ciocalteu reagent assay. ASC, individual phenolic compounds and pigments composition were analysed using HPLC technique. Seed protein composition was analysed based on SDS-PAGE. Fruit phenolic and dry matter contents were influenced to a large degree by pollen sources while ASC content did not. The type of male and female parents used in the study were found to have a considerable effect on these parameters. The biggest differences in fruit phytocompound contents were found between female parents. The ‘Geneva’ cultivar showed the highest concentration of the most bioactive compounds tested. Four phenolic acids and five flavonoids were present in the highest concentrations in tested kiwiberry fruit. Actinidia chinensis var. deliciosa ‘Tomuri’ pollen clearly modified the seed protein spectrum with a 17 and 23 kDa protein. The obtained results indicate that to achieve desired fruit biochemical characteristics, the pollen source (male vines) should be selected individually for particular female cultivars, especially in the case of polyphenol content. Our findings suggest that not only A. arguta but also A. arguta var. purpurea and A. chinensis var. deliciosa ‘Tomuri’ males may be suitable as pollinizers for kiwiberry fruit production.

Characterizing hybrid populations of Actinidia arguta var. arguta and related species

Commercial cultivars from the genus Actinidia are mainly derived from larger fruited species like Actinidia chinensis var. chinensis and A. chinensis var. deliciosa. Small-fruited species such as Actinidia arguta var. arguta have been of interest for their smooth fruit skins and novel flavours, but have had limited commercial success to date, primarily because of their shorter storage ability and less robust handling properties. The New Zealand Institute for Plant & Food Research Limited (PFR)'s Motueka site has intra- and inter-specific populations based on A. arguta and other small-fruited Actinidia sp. We present data frequency distributions and correlations to demonstrate the variation in agronomically important traits. This is done by using various descriptive statistics, as well as fitting a mixed model which incorporates the pedigree structure in addition to year and trial effects, to obtain the best linear unbiased predictions (BLUPs) for all species and hybrids.

Cell wall changes in Actinidia arguta during softening

Abstract Actinidia arguta fruit, differing from conventional kiwifruit A. chinensis ‘Hort16A’ and ‘Hayward’ by size, skin appearance, softening rate and texture, were characterised regarding structural and cell wall changes during softening. Cell wall changes of A. arguta var. arguta ‘Hortgem Tahi’ were examined during softening using histological stains, immunolocalisation and cell wall composition analyses. ‘Hortgem Tahi’ fruit are bite-sized and have a skin that is considered edible by consumers, consisting of a cuticle, a living epidermis and a hypodermis of tightly packed thin-walled cells, containing condensed phenolic material. Beneath is the outer pericarp with large and small parenchyma cells, followed by the inner pericarp with seed-containing locules, and core tissue consisting of small, tightly packed parenchyma cells. Throughout the fruit are large numbers of mucilage-containing cells. At harvest, cell walls stain densely with toluidine blue; as fruit softens, staining is lost in the outer pericarp but retained in the epidermis and hypodermis. At harvest, antibodies directed to cell wall epitopes bind to cell walls with a characteristic labelling pattern, but later as fruit soften these antibodies also label polysaccharides inside the cells. ‘Hortgem Tahi’ softens within five days after harvest. Cell wall composition analyses showed that during the softening process, galactose loss as well as pectin solubilisation started at an earlier firmness stage compared to ‘Hayward’ fruit that take about thirty days to soften. ‘Hortgem Tahi’ shows similar internal structural characteristics and cell wall changes compared with conventional kiwifruit. However, they differ in skin structure, the presence of mucilage filled cells, and the occurrence of pectin labelling within the lumen of cells at the ripe fruit stage which may be responsible for the gelatinous texture of the ripe fruit. The comparatively fast softening rate may be caused by an early reduction of galactose content increasing cell wall porosity that supports pectin solubilisation.

Agronomic Trait Variations and Ploidy Differentiation of Kiwiberries in Northwest China: Implication for Breeding.

Polyploid plants often have higher biomass and superior crop qualities. Breeders therefore search for crop germplasm with higher ploidy levels; however, whether higher ploidy levels are associated with better performance remains unclear. Actinidia arguta and related species, whose commercialized fruit are referred to as kiwiberries, harbor a series of ploidy races in nature, offering an opportunity to determine the link between ploidy levels and agronomic traits. In the present study, we determined the ploidy levels of A. arguta var. arguta, A. arguta var. giraldii, and A. melanandra in 16 natural populations using flow cytometry, and examined 31 trait variations in fruits, leaves and flowers by field observations, microscopic examination and laboratory analyses. Our results showed that octaploid and decaploid A. arguta var. giraldii had larger dimension of leaves than tetraploid A. arguta var. arguta and A. melanandra, but their fruits were significantly smaller. In addition, A. arguta var. giraldii (8x and 10x) had higher contents of nutrients such as ascorbic acid and amino acids; however, some important agronomic traits, including the content of total sugar and total acid, were significantly lower in the octaploids and decaploids. Moreover, octaploids and decaploids did not result in greater ecological adaptability for the challenging environments and climates. In conclusion, the differentiation of ecological adaptability and traits among natural kiwiberries' cytotypes suggested that higher ploidy levels are not inevitably advantageous in plants. The findings of A. arguta and related taxa in geographical distribution and agronomic trait variations will facilitate their germplasm domestication.

Flora do Rio de Janeiro: Hydrocharitaceae

Resumo A família Hydrocharitaceae é cosmopolita; composta por 17 gêneros e 127 espécies. São ervas aquáticas fixas ou livres, flutuantes, submersas ou emersas, em água doce, salobra ou salgada. No Brasil ocorrem seis gêneros e cerca de 15 espécies. A fim de conhecer a real diversidade da família no estado do Rio de Janeiro foi realizado o levantamento em herbários e coletas. Registraram-se seis espécies autóctones e duas alóctone em cultivo. Apalanthe granatensis, encontrada em represas, rios e lagoas de água doce, possui flores bissexuais. Egeria densa, semelhante a A. granatensis, distingue-se pelas flores unissexuais. Halophila decipiens, ocorre em praias da Baia de Guanabara; caracteriza-se pelo caule rizomatoso e folhas elípticas. Limnobium laevigatum, ocorre flutuando livremente em lagoas e emersa em alagados, possui folhas flutuantes com espessamento aerenquimatoso abaxial e/ou folhas emersas sem espessamento. Najas arguta var. arguta, exibe caule inerme, folhas concentradas no ápice dos ramos e semente fusiforme, Najas marina, apresenta dentes no caule e nervura principal e semente elíptica; ambas encontradas em lagoas costeiras. Elodea canadensis e Vallisneria sp. foram encontradas em cultivo.

Characterization and Quantification of Anthocyanins in Red Kiwifruit (Actinidia spp.)

Red-fleshed fruit occur in a small number of distantly related taxa in different sections of the genus Actinidia (kiwifruit). We describe and identify the anthocyanin profile of fruit of several Actinidia species. Differences in the relative amounts of cyanidin- and delphinidin-based anthocyanins determine whether the fruit appear red or purple. Cyanidin derivatives have been found in all Actinidia species that contain anthocyanins, whereas delphinidin derivatives are limited to two taxa: A. melanandra and A. arguta var. purpurea . The fruit of these not only contain a wider range of anthocyanins, but they also have greater concentrations. Anthocyanins of most Actinidia species are usually conjugated with either xylosyl-galactose or galactose, whereas A. deliciosa anthocyanins are conjugated with glucose and galactose.

Las <i>Najadaceae</i> de Cuba

This is a study of the family Najadaceae in Cuba. The presence of Najas marina, N. guadalupensis f. floridana and N. arguta var. arguta is confirmed, and the area of distribution of N. guadalupensis f. guadalupensis and N. wrightiana is extended. A general key, illustrations and distribution maps are included.

New reports of chromosome numbers in Actinidia (Actinidiaceae)

Chromosome numbers are reported for the first time for seven taxa of Actinidia: A. arguta var. purpurea, 2n = 8x = c. 232; A. deliciosa var. chlorocarpa, 2n = 6x= 174; A. deliciosa var. coloris, 2n = 6x = 174; A. glaucophylla, 2n = 2x = 58; A. guilinensis, 2n = 2x = 58; A. indochinensis, 2n = 2x = 58 and A. setosa 2n = 2x = 58. Ploidy variation has also been observed in A. melanandra and confirmed in A. chinensis var. chinensis: 2n = 2x = 58 and 2n = 4x = 116. Chromosome numbers for another 11 Actinidia taxa were found to be in agreement with those previously reported. Chromosome numbers were the same for male and female plants of the same taxon. Detailed studies of chromosome morphology was not possible under the light micro scope because of the small size of Actinidia chromosomes.

Microcallus formation from leaf mesophyll protoplasts in the genus Actinidia Lindl

Microcallus (more than 60 cells) formation was obtained from leaf mesophyll protoplasts of 6 species and varieties in the genus Actinidia Lindl. (kiwifruit). The best results were achieved by using liquid over agarose culture for A. arguta var. arguta, liquid and agarose disc type culture for A. arguta var. purpurea, agarose disc type culture for A. arguta cv. Issaï and A. deliciosa and liquid agarose bead type- and disc type culture for A. kolomikta and A. polygama. Several factors influencing purification, browning, survival and sustained division of the protoplasts are briefly discussed.

Leaf flavonoids of Actinidia

Leaf flavonoid chemistry of 22 taxa of Actinidia (Actinidiaceae) was studied. Flavonols predominated and the taxa studied were characterised by the presence of mono-, di- and in some cases, triglycosides. The taxa were distinguished from one another by their flavonoid profiles. Predominant glycosides were glucosides, galactosides, rhamnosides, rhamnoglucosides and rhamnogalactosides but not all glycosides were present in all taxa. C-Glycosylflavones were found in three species. Infrataxon variation was observed, e.g. A. polygama and A. arguta var. arguta. The genus has been subdivided on morphological grounds but large differences in flavonoid composition have shown up within all but one subdivision ( Leiocarpae Series Solidae). It is shown that flavonoid composition can be used to confirm the parentage of putative hybrids.

Flow cytometric analysis ofActinidiaspecies

Abstract Nuclei were extracted from shoot apices of Actinidia species, treated with ribonuclease, stained with propidium iodide, and then analysed by flow cytometry. Nuclei from shoots and from callus of in vitro cultures were also analysed. Diploid, tetraploid, hexaploid species, and hybrids between diploid and hexaploid could be accurately identified. No mixoploidy or aneuploidy was found in shoots from potted plants or from shoots of tissue-cultured plants following repeated subculturing. However, two cytotypes (DNA dodecaploid) of A. deliciosa were identified in plant populations derived by adventitious organogenesis from callus. The cytotypes were stable over a 2 year period. The nuclear DNA content of Actinidia species was determined by co-chopping shoot apices with Hordeum, Vigna, and Zea standards. Nuclear DNA contents were 1.53, 3.09, and 4.43 pg DNA per 2 C nucleus for A. chinensis var. chinensis, A. arguta var. arguta, and A. deliciosa var. deliciosa, respectively.

Three New Corticiaceous Fungi (Basidiomycotina, Aphyllophorales) from Japan.

Two new species, Athelia repetobasidifera and Sistotrema microsporum and one new variety, Grandinia arguta var. sphaerospora are described from Japan. The first fungus is characterized by lacking clamps at septa, having small basidiospores and often producing new basidia by the intrabasidial repetition. The second fungus is distinguishable from the previously described species in having smaller basidia and basidiospores. The third one, a new variety, differs from the type variety primarily in having globose and thick-walled (up to 0.5μm thick) basidiospores.

A flavonol triglycoside from Actinidia arguta var. giraldii.

In the course of a chemotaxonomic study of the genus Actinidia a new flavonol triglycoside, quercetin 3-O-beta-D-[2G-O-beta-D-xylopyranosyl-6G-O-alpha-L-rhamnopyranosyl] glucopyranoside was identified amongst the 15 flavonols found in Actinidia arguta var. giraldii. This compound was characterized, along with quercetin 3-O-beta-D-xylopyranosyl-(1-2)-O-beta-D-glucopyranoside, by 1H and 13C NMR spectroscopy. The kaempferol analogues were also isolated.

Chromosome studies in someActinidiataxa and implications for breeding

Abstract Microsporogenesis was studied in eleven Actinidia taxa including A. deliciosa (kiwifruit) and in an interspecific hybrid. From chromosome counts at meiotic metaphase 1 or diakinesis, eight taxa were classified as diploids and two as tetraploids and A. deliciosa was confirmed as hexaploid. A putative 2n = 2x, 2n = 4x, 2n = 6x, x = 29 basis for the genus is therefore supported. Chromosomes in all taxa were very small. Three diploids and two polyploids analysed for meiotic pairing behaviour were all characterised by low chiasma frequencies per bivalent. Chromosome configurations other than bivalents were rare in A. arguta var. arguta (4x) and A. deliciosa (6x), indicating there may be genetic control of chiasmata distribution in these polyploids.

Taxonomy of the genus Najas L. (Najadaceae) in the neotropics

The taxanomy, geography and evolutionary affinities are treated for the nine Najas taxa occurring in the sub-tropical and tropical regions of the Americas. Outstanding taxonomic characters are fruit dimensions, seed reticulations, leaf sheaths and teeth along leaf blades. Najas conferta (A. Br.) A. Br., N. marina L. and N. guadalupensis (Sprengel) Magnus are dispersed throughout the Neotropics. Two forms of N. guadalupensis, forma guadalupensis and forma floridana (Haynes and Wentz) Lowden, comb. nov., are recognizable on the basis of visibility of teeth along leaf margins. The original descriptions and types chosen for N. conferta and N. wrightiana A. Br. are presented in order to clarify past confusion between these two very distinct species. Primarily, N. wrightiana is restricted to northern Mesoamerica and Cuba, with a more recent extension into southern Florida and the Bahamas. The presence of N. graminea Del. in the flora of Brazil is substantiated with the collection of N. graminea var. minor Rendle from the State of Maranhão. In South America, N. microcarpa Schumann is treated as a species complex demonstrating close affinities with N. arguta H.B.K. and N. conferta. Najas arguta var. arguta and N. arguta var. podostemon (Magnus) Lowden, comb. nov., are different in length of seeds and areolae. What has recently been misinterpreted as N. ancistrocarpa A. Br. ex Magnus in North America is really N. conferta which reaches its northernmost extension in the areas of Georgia and Florida in the southeastern United States.