Starch accumulation and agronomical performance of Syrah under winter cycle: responses to pruning and ethephon management

In the Brazilian Southeast, 'Syrah' grape harvested during the winter reaches better quality index than those from summer harvest. However, the management of annual double pruning to produce two grapevine growth cycles (vegetative cycle: spring – summer; reproductive cycle: autumn – winter) has increased the vineyard production costs and the vine reserve accumulation can be compromised. This study had two main objectives to improve the winter cultivation: i) to validate single pruning carried out only in summer (February) (experiment 1); to increase the reserve accumulation by ethephon (ethrel) sprayed two months before yield pruning (experiment 2). Both experiments were carried out in south of Minas Gerais State using three years old field-grown 'Syrah' grapevines grafted onto '1103 Paulsen' and trained in a vertical shoot position. The results from experiment 1 showed that grapevines pruned in summer also need to be pruned during the winter after grape harvest to avoid bud infertility during the following autumn-winter season. Single pruning reduced the starch contents in shoots, trunks and roots sampled before yield pruning and the commercial grape harvest was completely unavailable due to unfruitful shoots. On the other hand, the autumn-winter cycle was improved by ethephon sprayed in the previous vegetative growing cycle (summer cycle). During the autumn-winter cycle, sprayed grapevines showed higher starch content in trunks, high vegetative vigor and the yield and grape quality were not negatively affected

Near full-length genome analysis of low prevalent human immunodeficiency virus type 1 subclade F1 in São Paulo, Brazil

Background: The genetic diversity of the human immunodeficiency virus type 1 (HIV-1) is critical to lay the groundwork for the design of successful drugs or vaccine. In this study we aimed to characterize and define the molecular prevalence of HIV-1 subclade F1 currently circulating in Sao Paulo, Brazil. Methods: A total of 36 samples were selected from 888 adult patients residing in Sao Paulo who had previously been diagnosed in two independent studies in our laboratory as being infected with subclade F1 based on pol subgenomic fragment sequencing. Proviral DNA was amplified from the purified genomic DNA of all 36 blood samples by 5 fragments overlapping PCR followed by direct sequencing. Sequence data were obtained from the 5 fragments of pure subclade F1 and phylogenetic trees were constructed and compared with previously published sequences. Subclades F1 that exhibited mosaic structure with other subtypes were omitted from any further analysis Results: Our methods of fragment amplification and sequencing confirmed that only 5 sequences inferred from pol region as subclade F1 also holds true for the genome as a whole and, thus, estimated the true prevalence at 0.56%. The results also showed a single phylogenetic cluster of the Brazilian subclade F1 along with non-Brazilian South American isolates in both subgenomic and the full-length genomes analysis with an overall intrasubtype nucleotide divergence of 6.9%. The nucleotide differences within the South American and Central African F1 strains, in the C2-C3 env, were 8.5% and 12.3%, respectively. Conclusion: All together, our findings showed a surprisingly low prevalence rate of subclade F1 in Brazil and suggest that these isolates originated in Central Africa and subsequently introduced to South America.Fundacao de Amparo a Pesquisa do Estado de Sao Paulo (FAPESP)[06/50096-0