The molecular mechanisms of plant recognition, colonization, and nutrient exchange between diazotrophic endophytes and plants are scarcely known. Herbaspirillum seropedicae is an endophytic bacterium capable of colonizing intercellular spaces of grasses such as rice and sugar cane. The genome of H. seropedicae strain SmR1 was sequenced and annotated by The Paraná State Genome Programme—GENOPAR. The genome is composed of a circular chromosome of 5,513,887 bp and contains a total of 4,804 genes. The genome sequence revealed that H. seropedicae is a highly versatile microorganism with capacity to metabolize a wide range of carbon and nitrogen sources and with possession of four distinct terminal oxidases. The genome contains a multitude of protein secretion systems, including type I, type II, type III, type V, and type VI secretion systems, and type IV pili, suggesting a high potential to interact with host plants. H. seropedicae is able to synthesize indole acetic acid as reflected by the four IAA biosynthetic pathways present. A gene coding for ACC deaminase, which may be involved in modulating the associated plant ethylene-signaling pathway, is also present. Genes for hemagglutinins/hemolysins/adhesins were found and may play a role in plant cell surface adhesion. These features may endow H. seropedicae with the ability to establish an endophytic life-style in a large number of plant species.

Traditional Knowledge and Management of Feijoa (Acca sellowiana) in Southern Brazil. This paper investigates traditional knowledge of the use and management of Acca sellowiana in southern Brazil. Fifty-six informants from three rural communities were assigned to one of four subgroups ("maintainers," "managers," "cultivators," or "users") based on their responses regarding management and use of A. sellowiana. Traditional knowledge related to use of this species is widespread among rural residents, but traditional knowledge related to management is fragmented depending on whether one uses, manages, or cultivates the species. Knowledge held in rural communities suggests that A. sellowiana could play an expanded role in local economies as well as biodiversity conservation. We suggest that participatory research could stimulate greater local use as well as on-farm conservation of A. sellowiana.

The critically endangered Brazilian pine, also called araucaria, (Araucaria angustifolia (Bertol.) Kuntze) is a key species of the Araucaria moist forest (AMF, Mixed Ombrophilous Forest). Illegal timber extraction, agricultural conversion and severe degradation have reduced the AMF to only 13 per cent of its original cover, with climate change imposing additional challenges for cold adapted species such as araucaria. Previous studies have assessed climate change impacts on A. angustifolia, but have been limited by analysis constraints. Here, we used a machine learning technique to understand how land use and climate change might affect the distribution of A. angustifolia, and to evaluate the effectiveness of existing protected areas (PAs) to conserve this species. Our results demonstrated that despite the recent efforts to conserve the Atlantic Forest, conversion of natural habitats into forest plantation still occurs within araucaria’s distribution range. Our model predicted a drastic reduction in environmentally suitable areas for this species of up to 77 per cent in the coming decades. Also, the existing PAs show low efficacy to protect suitable areas in the future. Combined, these results suggest that A. angustifolia will be under great threat within the next few decades and the development of conservation strategies to save this species is essential. Ideally, the conservation programs should integrate in situ and on farm approaches, including forest management strategies. Although in situ strategies play an important role as gene banks, on-farm strategies can be used to promote the restoration and expansion of A. angustifolia populations in the areas predicted as suitable.

The aim of the present work was to physicochemically characterize the fruits of accessions of feijoa [Acca sellowiana (O. Berg.) Burret] active germplasm bank (BAG), located in São Joaquim, Brazil. The identification of accessions with desirable fruit traits will facilitate species breeding and cultivation. During seven harvests (2004-2017), 10 fruits per plant of 229 accessions were evaluated for fruit diameter, length and weight, skin and pulp weight, skin thickness, pH, titratable acidity, and soluble solids content, in addition to the qualitative descriptors insertion of sepals, fruit shape, sheen of skin, vacuum, color of skin and pulp, and texture and roughness of the skin. Descriptive statistics, correlations, and a multivariate analysis were applied to better understand the nature and magnitude of the variables. The mean +1SD was used to identify the best accessions for breeding purposes. Active germplasm bank accessions revealed significant phenotypic diversity for the physicochemical characteristics of the fruits, and the year effect represented the largest contribution to the variance for all evaluated characteristics, except fruit length. The characteristics total fruit weight, fruit diameter, and skin thickness are strongly related to pulp yield (%). There is high phenotypic diversity in accessions of feijoa conserved in the São Joaquim BAG, which will allow different traits of this species to be genetically improved.

Acca sellowiana (Berg) Burret is a predominantly allogamous species with hermaphrodite flowers that has barriers to self-fertilisation such as dichogamy by protogyny and self-incompatibility. This study aimed to identify when self-incompatibility occurs in A. sellowiana flowers submitted to self-pollinations. Pollinations were made using nine known self-incompatible accessions in several treatments including manual cross-pollination, manual self-pollination, no pollination and natural pollination. Flowers were pollinated and pistils collected at times ranging from 1 to 30 days after pollination (DAP). In both cross- and self-pollinations the fertilisation occurred from 18 DAP and the zygote was visualised at 24 and 26 DAP, respectively. The abscission of the self-pollinated flowers increased from 26 DAP onwards, when significant differences (P < 0.05) were found for the percentage of abscission among self-pollinated and cross-pollinated flowers. At 30 DAP, 72% of self-pollinated flowers were abscised. The size of ovules and ovaries of self-pollinated flowers showed no significant difference from those of non-pollinated flowers throughout 30 DAP, while those from cross-pollinated flowers were significantly larger (P < 0.05) than the other treatments from 22 and 24 DAP, respectively. After 40 DAP, there was no fruit development in self-pollination and non-pollination treatments. Our study brings greater clarity to the mechanism of self-incompatibility in A. sellowiana, indicating late-acting self-incompatibility occurring through the rejection/abscission of self-pollinated flowers precisely after syngamy and zygote formation.

RESUMO -Foi avaliada a manutenção da qualidade pós-colheita dos frutos em cultivares brasileiras de goiabeira-serrana. Frutos das cultivares Alcântara, Helena, Mattos e Nonante foram colhidos na maturação comercial, no município de São Joaquim-SC, e armazenados a 4±1 o C (90±5% UR), durante 21 dias, seguido de 8 e 48 h a 23±1 ºC (75±5% UR). Foram avaliadas a composição mineral (N, K, Mg e Ca) na colheita e a qualidade dos frutos na colheita e após o armazenamento. Frutos da cultivar Nonante apresentaram na colheita maiores valores de acidez titulável (AT) pH e de atributos de textura, e menores valores de pH e da relação sólidos solúveis/acidez titulável (SS/AT), sendo que, após o armazenamento refrigerado, este comportamento foi reduzido, com menores diferenças em relação às demais cultivares. Frutos de 'Nonante' apresentaram também maiores teores de K na casca e polpa, e menores teores de N na polpa e, após o armazenamento refrigerado, cor verde menos intensa na casca e menor escurecimento de polpa. Em relação aos dados de colheita, após o armazenamento refrigerado, houve maior redução na AT (41%) do que no teor de SS (8,6%), o que ocasionou acentuado aumento na relação SS/AT (52,5%), considerando valores médios das quatro cultivares. Isto evidencia que, em goiaba-serrana, os ácidos orgânicos representam o principal substrato respiratório durante o armazenamento, o que compromete a qualidade sensorial pelo aumento na relação SS/AT. Frutos de 'Alcântara' foram também avaliados quanto aos efeitos do dano mecânico na colheita e do retardo no armazenamento refrigerado, na qualidade após o armazenamento. O dano mecânico na colheita (dano por queda, a uma altura de 50 cm, sobre uma superfície rígida) ocasionou mínimo comprometimento da qualidade após o armazenamento refrigerado. Frutos desta cultivar apresentaram redução na AT (31%), textura da periderme (33%) e força para a compressão (13%), e aumento no pH (20%) e na relação SS/AT (48%), com o retardo no armazenamento refrigerado (de 0h para 48h a 18±2 o C/70±5% UR). Termos para indexação: Acca sellowiana Berg., dano mecânico, retardo no resfriamento, composição mineral, acidez, textura. QUALITY AND POSTHARVEST CONSERVATION POTENTIAL OF THE FRUIT IN BRAZILIAN CULTIVARS OF FEIJOAABSTRACT -This study was carried out to assess the postharvest quality preservation of the fruit in Brazilian cultivars of feijoa. Fruit of cultivars Alcântara, Helena, Mattos and Nonante were harvest at commercial maturity, in São Joaquim, southern Brazil, and cold stored at 4±1 o C (90±5% RH), during 21 days, followed by 8 and 48 h at 23±1 ºC (75±5% RH). Fruit mineral content (N, K, Mg and Ca) was assessed at harvest, and fruit quality was assessed at harvest and after cold storage. At harvest, fruit of 'Nonante' had higher values of titratable acidity (TA), and texture attributes, and lower values of pH and soluble solids content/titratable acidity ratio (SSC/TA) than fruit of the other three cultivars. However, after cold storage, these differences were less expressive. Fruits of 'Nonan...

The pineapple guava (Acca sellowiana), known in portuguese as the goiabeira-serrana or "Feijoa", is a native fruit tree from southern Brazil and northern Uruguay that has commercial potential due to the quality and unique flavor of its fruits. Knowledge of genetic variability is an important tool in various steps of a breeding program, which can be facilitated by the use of molecular markers. The conservation of repeated sequences among related species permits the transferability of microsatellite markers from Eucalyptus spp. to A. sellowiana for testing. We used primers developed for Eucalyptus to characterize A. sellowiana accessions. Out of 404 primers tested, 180 amplified visible products and 38 were polymorphic. A total of 48 alleles were detected with ten Eucalyptus primer pairs against DNA from 119 A. sellowiana accessions. The mean expected heterozygosity among accessions was 0.64 and the mean observed heterozygosity 0.55. A high level of genetic diversity was also observed in the dendrogram, where the degree of genetic dissimilarity ranged from 0 to 65% among the 119 genotypes tested. This study demonstrates the possibility of transferring microsatellite markers between species of different genera in addition to evaluating the extent of genetic variability among plant accessions.

This study aimed to understand post-agricultural natural forest regeneration in the Southern Brazilian Atlantic Forest and its possible role as a cost-effective, passive approach to forest restoration. The study characterized vegetation structure, floristic composition, and the dynamics of secondary forest chronosequences. Data were collected from 159 plots (10 × 10 m each) across forest remnants in Santa Catarina State, covering forest ages that ranged from 2 to 60 years of regeneration after swidden agriculture. Only areas with no signs of degradation were sampled in order to provide a description of vegetation characteristics that could be used to identify and monitor natural regeneration. A total of 11,455 woody plants were identified and classified into 334 species representing 71 families. As the succession process unfolds, the continuous turnover of species makes forests more diverse and structurally complex. Floristic similarity among forest types is observed during the early stages of succession, but decreases over time. Pioneer species dominate young secondary forests, representing about 40% of the basal area up to 10 years of regeneration. Shade-tolerant species start colonizing the sites at early ages; however, they become more important structural elements only after 30 years of succession. The observed patterns of forest structure and species diversity largely conform to the post-agricultural succession seen in many tropical forests. The high species diversity found in this study highlights the importance of natural regeneration as a strategy to restore ecosystems. Floristic data can be used as a reference for choosing suitable species for active restoration, as well as contributing to the design of integrated restoration strategies. We herein reinforce the potential of natural regeneration as part of large-scale restoration programs, which would be particularly attractive to family farmers by the low cost of supplies and labor.