Isolation and characterization of microsatellite markers in Acca sellowiana (Berg) Burret

Acca sellowiana has commercial potential because of the quality and the unique flavor of its fruit. Conservation of natural populations and management of breeding programmes would benefit from the availability of molecular markers that could be used to characterize levels and distribution of genetic variability. Thus, 13 microsatellite markers were developed from an enriched genomic library of A. sellowiana. They were characterized using 40 samples. The expected and observed heterozygosities ranged from 0.513 to 0.913 and from 0.200 to 0.889, respectively. These are the first microsatellite loci characterized from A. sellowiana that will contribute to improve researches on the genetic conservation, characterization and breeding.     

三个不同品种费约果的花粉-胚珠比及花粉粒形态的扫描电镜观察

利用扫描电子显微镜对费约果三个品种的花粉粒显微结构形态进行观察,计算三个品种费约果的花粉-胚珠比,并据此分析费约果的形态特征和分类学意义,划分其繁育系统类型。结果表明:‘Coolidge’、‘Mammoth’和‘Unique’三个品种的花粉-胚珠比分别为6±2.37、4.41±1.47和8.52±2.84,其繁育系统为闭花受精型;费约果花粉粒呈辐射对称,极面观近似等边三角形,有明显的三孔沟(合沟),具角萌发孔,其赤道面观为椭圆形,花粉粒表面具颗粒状雕纹;三个品种花粉粒形态相比之下也略有差异,但不明显。从费约果与同科4个属花粉粒的对比中可以得出,费约果花粉粒形态结构符合桃金娘科植物的主要特征,其花粉粒形态在分类学上具有重要意义。     

Differential proteomic analysis of developmental stages of <Emphasis Type="Italic">Acca sellowiana</Emphasis> somatic embryos

Feijoa (Acca sellowiana, Myrtaceae), a native fruit species from southern Brazil and northern Uruguay, is considered to constitute a reference system for somatic embryogenesis in woody dicots. This in vitro regenerative pathway is an efficient micropropagation method, and a suitable model system for studies in plant developmental physiology. This study attempts to detect and identify proteins that are expressed during the different developmental stages of somatic embryos of A. sellowiana. Using high resolution two-dimensional polyacrylamide gel electrophoresis (2-DE), a high degree of similarity between protein profiles of the assayed somatic embryos was observed. Of the 74 different protein spots extracted for analysis, 60 were identified by means of 2-DE/MALDI-TOF/MS. Twelve proteins were expressed in all the assayed stages. Ten proteins were expressed in the initial stages and 22 proteins were expressed in the mature developmental stages of somatic embryos. Only one protein was expressed exclusively in the torpedo stage, whereas four were expressed in the pre-cotyledonary, and none in the cotyledonary stage. The proteins identified were involved in the synthesis of phenylalanine ammonia-lyase, a conspicuous polyphenol present in the induction of feijoa embryogenic cultures. The presence of essential proteins of nitrogen metabolism, such as the cytosolic glutamine synthetase protein, was also observed. The physiological implications of these findings are discussed.     

Induction of pollen callus in anther cultures of Feijoa sellowiana Berg. (Myrtaceae)

Summary Anthers of Feijoa sellowiana Berg. (feijoa) produced pollen callus when cultured in Murashige and Skoog medium containing 2,4-dichlorophenoxyacetic acid and benzyladenine or in nurse cultures. Somatic callus was also formed in large amounts from the connective and from the cut end of the filament. Anthers containing microspores at the stage immediately prior to the first pollen mitosis cultured in the presence of 3% sucrose, presented the highest frequencies of induction. Androgenetic divisions were initiated by the formation of two morphologically equal cells, the so-called B-pathway. Attempts to regenerate pollen plants were unsuccessful but leaf-like structures could be obtained in regeneration media containing combinations of gibberellic acid and benzyladenine.Abbreviations 2,4-D 2,4-diclorophenoxyacetic acid - BA benzyladenine - FDA fluorescein diacetate - GA₃ gibberellic acid - Kn kinetin - MS Murashige and Skoog (1962) medium     

Biotechnological suitability of Saccharomycodes ludwigii for fermented beverages

Nineteen Saccharomycodes ludwigii strains were tested for the production of secondary products in grape must fermentation. A predominant metabolic pattern characterized by high production of isobutyl alcohol, acetoin and ethyl acetate was obtained. The occurrence of some strains producing enhanced amounts of these compounds suggests a potential utilization of this species for industrial applications. Feijoa juice was inoculated with a selected S'codes ludwigii strain in comparison to a control strain of S. cerevisiae and evaluation of the fermented products was carried out by 30 consumers with respect to the odour, flavour and taste. The sample fermented by S'codes ludwigii was characterized by a fresh odour with a fruity flavour, identified as flavour of apple and kiwi-fruit. This product was compared to apple juice, with a more acid taste. Despite the high concentrations of acetic acid, this beverage might be considered a potential summer refreshing drink, addressed to a target of consumers who prefer fruit drinks that leave a slightly acid and little sugary taste in the mouth.     

Secondary metabolites from the leaves of Feijoa sellowiana Berg

The investigation of the lipid extract of leaves of Feijoa sellowiana cultivated along the east coast of Sicily has yielded in addition to the widespread secondary metabolites: alpha-tocopherol, flavone, stigmasterol and beta-carotene, an inseparable mixture of tyrosol esters of lignoceric (1a), cerotic (1b) and montanic (1c) acids, and a novel galactolipid identified as (2S)-1,2,6'-tri-O-[(9Z,12Z,15Z)-octadeca-9,12,15-trienoyl]-3-O-beta-D-galactopyranosyl glycerol (2).     

Morphohistological analysis and histochemistry of Feijoa sellowiana somatic embryogenesis

Summary. Morphohistological analysis and histochemical studies were carried out during the induction and development of Feijoa sellowiana somatic embryos. Zygotic embryos were cultured on LPm medium containing 2,4-dichlorophenoxyacetic acid (20µM) and glutamine (8mM). Somatic embryogenesis could be induced from embryogenic cells that originated in meristematic centers or from clusters of cells. The presence of few starch grains and abundant protein bodies was observed in the globular and early torpedo stages, while in torpedo and cotyledonary-stage somatic embryos an enhanced synthesis of starch grains was associated with the accumulation of reserves to be used in the conversion of the embryos to plantlets. Proteins were predominantly observed in protoderm cells, as well as in the meristematic apical region of torpedo and cotyledonary-stage somatic embryos.Correspondence and reprints: Departamento de Fitotecnia, Centro de Ciências Agrárias, Universidade Federal de Santa Catarina, C.P. 476, 88034-001 Florianópolis, SC, Brazil.     

Three new flavonoids,proanthocyanidin, and accompanying phenolic constituents from Feijoa sellowiana

Our investigation of phenolic constituents of fruits, flower buds, and leaves of Feijoa sellowiana led to the isolation of twenty-one phenolics including three new gossypetin glycosides 1–3, and also the purification of a proanthocyanidin fraction. A high-performance liquid chromatography method for simultaneous analysis of phenolic constituents was established and then used to investigate the phenolic profiles of the parts of the plant species, to show the presence of characteristic flavonoids and ellagic acid derivatives or ellagitannins in the extracts from fruits, flower buds, and leaves. The branch extract profile also suggested the presence of alkylated ellagic acids as characteristic constituents. Inhibitory effects of feijoa flavonoids on mushroom tyrosinase were seen, although in some cases this may have resulted from direct interaction with the enzyme. Cytotoxic effect of the proanthocyanidin fraction was also shown.     

The effectiveness of nitrogen sources in Feijoa somatic embryogenesis

Immature and mature zygotic embryos excised from Feijoa fruits were employed as explants and the effects of NH₄ ⁺ and NO₃ ^– ionic concentration in basal LPm culture medium supplemented with 2,4-D (10 M) were evaluated. Moreover, the addition of 4 mM of Asn, Gln, and Arg, and levels of Gln (0 to 8 mM) were tested. The original NH₄ ⁺ and NO₃ ^– concentration present in the LPm culture medium supplemented with Gln (4 mM) resulted in the highest somatic embryo number from immature zygotic embryos. For mature zygotic embryos, the addition of Asn, Gln or Arg to the basal LPm culture medium resulted in improved somatic embryogenesis induction. Ten weeks in culture allowed the highest somatic embryo number when mature zygotic embryos were used as explant. Half-strength MS culture medium supplemented with BAP (0.5 M) enhanced the conversion of somatic embryos to plantlets.     

费约果外植体灭菌及愈伤组织的诱导

以费约果(Feijoa sallowiana Berg.)嫩叶和带芽茎段作为外植体,研究费约果愈伤组织诱导的最佳条件和方法.结果表明:(1)最佳基本培养基是MS;(2)二步灭菌法优于一步灭菌法;(3)嫩叶和带芽茎段愈伤组织诱导的最佳活性炭浓度分别为2.0 g L-1和3.0 g L-1;(4)最佳青霉素浓度分别为200 mg L-1和50 mg L-1;(5)光培养方式优于暗培养方式.(6)费约果嫩叶诱导愈伤组织的最佳培养基是MS 2.0 mgL-1 2,4-D 1.0 mg L-1 KT(或0.1 mg L-1NAA);(7)带芽茎段的最佳培养基是MS 1.0 mg L-16-BA 0.5 mg L-1NAA 1.0 mg L-1GA或MS 2.0 mg L-16-BA 0.1 mgL-1NAA 1.0 mgL-1GA.