A combined approach involving ampelographic description, berry oenological traits and molecular analysis to study native grapevine varieties of Greece

A combined approach involving phenotypical characterization (ampelographic description and oenological traits) and molecular analysis was applied on 91 accessions of native Greek grape varieties plus 3 references, all conserved in the Ampelographic Collection of the Aristotle University of Thessaloniki. The accessions were described in accordance to 48 OIV descriptors. Their berry oenological traits were determined at maturity to detect a high juice sugar concentration in most of the assessed varieties, whereas the titratable acidity was found to be extremely low, particularly in the white accessions. Moreover, skin anthocyanin and phenolic content fluctuated from 0.09 to 39.4 mg∙g-1 f.w. and from 2.05 to 30.65 mg∙g-1 f.w. respectively, whereas seed phenolic content was in the range of 2.83 and 32.72 mg∙g-1 f.w. Finally, the discriminative SSR analysis confirmed the differences and similarities among the analyzed varieties as can be evinced from the phylogenetic analysis where close genetic relationship has been detected between 'Fokiano' and 'Armeletousa', 'Moschato Spinas' and 'Moschato Samou', 'Vilana' and 'Asprouda Patron', and 'Mouchtouri' and 'Mavro Spetson'. In all these occasions, the parts of each pair possess similar morphological characteristics

Transcriptomic Events Involved in Melon Mature-Fruit Abscission Comprise the Sequential Induction of Cell-Wall Degrading Genes Coupled to a Stimulation of Endo and Exocytosis

Background: Mature-fruit abscission (MFA) in fleshy-fruit is a genetically controlled process with mechanisms that, contrary to immature-fruit abscission, has not been fully characterized. Here, we use pyrosequencing to characterize the transcriptomes of melon abscission zone (AZ) at three stages during AZ-cell separation in order to understand MFA control at an early stage of AZ-activation. Principal Findings: The results show that by early induction of MFA, the melon AZ exhibits major gene induction, while by late induction of MFA, melon AZ shows major gene repression. Although some genes displayed similar regulation in both early and late induction of abscission, such as EXT1-EXT4, EGase1, IAA2, ERF1, AP2D15, FLC, MADS2, ERAF17, SAP5 and SCL13 genes, the majority had different expression patterns. This implies that time-specific events occur during MFA, and emphasizes the value of characterizing multiple time-specific abscission transcriptomes. Analysis of gene-expression from these AZs reveal that a sequential induction of cell-wall-degrading genes is associated with the upregulation of genes involved in endo and exocytosis, and a shift in plant-hormone metabolism and signaling genes during MFA. This is accompanied by transcriptional activity of small-GTPases and synthaxins together with tubulins, dynamins, V-type ATPases and kinesin-like proteins potentially involved in MFA signaling. Early events are potentially controlled by down-regulation of MADS-box, AP2/ERF and Aux/IAA transcription-factors, and up-regulation of homeobox, zinc finger, bZIP, and WRKY transcription-factors, while late events may be controlled by up-regulation of MYB transcription-factors. Significance: Overall, the data provide a comprehensive view on MFA in fleshy-fruit, identifying candidate genes and pathways associated with early induction of MFA. Our comprehensive gene-expression profile will be very useful for elucidating gene regulatory networks of the MFA in fleshy-fruit

Comparative investigation of physiological responses of field-grown Comparative investigation of physiological responses of field-grown

An important consideration in designing and managing forage systems is the knowledge of the physiological response mechanisms to cutting, especially when water deficit conditions are prevailing. The objective of this study was to determine the physiological response of Medicago sativa and Festuca arundinacea to cutting under different water regimes in a semi-arid Mediterranean region. In a field experiment, two cutting intensities were applied under irrigation and under rainfed (water deficit) conditions. Water potential, transpiration rate and stomatal conductance were measured. Based on the results, M. sativa showed higher transpirational water losses under rainfed conditions when compared to those of F. arundinacea, regardless of cutting treatment, because of the higher stomatal conductance. However, leaf water potential remained higher in M. sativa, suggesting a more effective root, stem or leaf related water uptake system. In addition, under water deficit, stomata of M. sativa were less sensitive to low values of water potential, probably resulting in higher productivity when compared to F. arundinacea. Cutting resulted in higher stomatal conductance and, therefore, higher transpiration in both species. Moreover, under water deficit, cutting positively affected water potential, especially in F. arundinacea, alleviating the effect of ageing.Keywords: cut, drought, stomatal conductance, transpiration, water potentialAfrican Journal of Range & Forage Science 2012, 29(3): 147–15

Cryoglobulinemia due to chronic viral hepatitis infections is not a major problem in clinical practice

Background: Essential mixed cryoglobulinemia (EMC) is a systemic disease frequently associated with chronic viral hepatitis. This study was conducted in order to assess the prevalence of EMC in patients with hepatitis B virus (HBV) or hepatitis C virus (HCV) infections. We also evaluated the possible associations of EMC with (1) the clinical, virological, and histological status of liver disease; (2) the presence of EMC-related symptoms; and (3) the response rate to interferon-α (IFN-α) treatment, in an attempt to address whether EMC is a major problem in hepatitis patients. Methodology: A total of 154 consecutive patients (104 with HBV and 50 with HCV infection) were investigated for the presence of rheumatoid factor (RF), cryoglobulins, and EMC-related manifestations. Sixty-two HBV patients were chronic carriers of hepatitis B surface antigen, 29 had chronic hepatitis B, and 13 HBV cirrhosis. Thirty-five HCV patients had chronic hepatitis C and 15 HCV cirrhosis. HCV genotyping was performed in 44 patients. Results: The prevalence of cryoglobulins was significantly higher (P<0.001) in HCV patients (46%) than in HBV patients (13.4%). EMC was associated with a high frequency of RF detection, older age, and longer duration of viral diseases. Weakness or malaise, arthralgias, and purpura were significantly more frequent in cryoglobulin-positive patients. These manifestations, however, were mild in most of the patients. The EMC-related symptoms were significantly associated with the presence of HCV infection, increased levels of cryoglobulins, and RF detection (P<0.01, P<0.05, and P<0.000005, respectively). Worse liver histology was unrelated to a higher prevalence or increased levels of cryoglobulins in both HBV and HCV infection. There was no relationship between EMC and a specific HCV genotype. IFN-α therapy led to the disappearance of cryoglobulins and EMC-related manifestations in most cases. The response rate to IFN-α was similar in both groups of patients (with and without EMC). Conclusions: A higher prevalence of EMC was observed in HCV patients than in HBV patients. However, this finding was unrelated to overt clinical manifestations of EMC, a specific HCV genotype, or worse liver histology. The latter suggests that EMC does not contribute to liver injury and vice versa, that EMC pathogenesis is rather unrelated to the degree of liver injury. From a clinical point of view, testing for cryoglobulins seems reasonable only for HCV patients with EMC-related manifestations, since this may have therapeutic consequences. RF detection could be used primarily as a surrogate marker for the existence of cryoglobulins. © 2001 Elsevier Science B.V. All rights reserved