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Despite the great diversity of plant growth-promoting bacteria (PGPB) with potential to partially replace the use of N fertilisers in agriculture, few PGPB have been explored for the production of commercial inoculants, reinforcing the importance of identifying positive plant-bacteria interactions. Aiming to better understand the influence of PGPB inoculation in plant development, two PGPB species with distant phylogenetic relationship were inoculated in maize. Maize seeds were inoculated with Bacillus sp. or Azospirillum brasilense. After germination, the plants were subjected to two N treatments: full (N+) and limiting (N-) N supply. Then, anatomical, biometric and physiological analyses were performed. Both PGPB species modified the anatomical pattern of roots, as verified by the higher metaxylem vessel element (MVE) number. Bacillus sp. also increased the MVE area in maize roots. Under N+ conditions, both PGPB decreased leaf protein content and led to development of shorter roots; however, Bacillus sp. increased root and shoot dry weight, whereas A. brasilense increased photosynthesis rate and leaf nitrate content. In plants subjected to N limitation (N-), photosynthesis rate and photosystem II efficiency increased in maize inoculated with Bacillus sp., whilst A. brasilense contained higher ammonium, amino acids and total soluble sugars in leaves, compared to the control. Plant developmental and metabolical patterns were switched by the inoculation, regardless of the inoculant bacterium used, producing similar as well as distinct modifications to the parameters studied. These results indicate that even non-diazotrophic inoculant strains can improve the plant N status as result of the morpho-anatomical and physiological modifications produced by the PGPB.

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The re-composition of deforested environments requires the prior acclimation of seedlings to full sun in nurseries. Seedlings can overcome excess light either through the acclimation of pre-existing fully expanded leaves or through the development of new leaves that are acclimated to the new light environment. Here, we compared the acclimation capacity of mature (MatL, fully expanded at the time of transfer) and newly expanded (NewL, expanded after the light shift) leaves of Guazuma ulmifolia Lam. (Malvaceae) seedlings to high light. The seedlings were initially grown under shade and then transferred to full sunlight. MatL and NewL were used for chlorophyll fluorescence and gas exchange analyses, pigment extraction and morpho-anatomical measurements. After the transfer of seedlings to full sun, the MatL persisted and acclimated to some extent to the new light condition, since they underwent alterations in some morpho-physiological traits and maintained a functional electron transport chain and positive net photosynthesis rate. However, long-term exposure to high light led to chronic photoinhibition in MatL, which could be related to the limited plasticity of leaf morpho-anatomical attributes. However, the NewL showed a high capacity to use the absorbed energy in photochemistry and dissipate excess energy harmlessly, attributes that were favoured by the high structural plasticity exhibited by these leaves. Both the maintenance of mature, photosynthetically active leaves and the production of new leaves with a high capacity to cope with excess energy were important for acclimation of G. ulmifolia seedlings.

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We analyzed the phenology of Ficus adhatodifolia Schott ex Spreng. (23 fig tree) and F. eximia Schott (12 fig tree) for 74 months in a remnant of seasonal semi-deciduous forest (23° 27'S and 51° 15'W), Southern Brazil and discussed their importance to frugivorous. Leaf drop, leaf flush, syconia production and dispersal were recorded. These phenophases occurred year-round, but seasonal peaks were recorded in both leaf phenophases for F. eximia and leaf flushing for F. adhatodifolia. Climatic variables analyzed were positively correlated with reproductive phenophases of F. adhatodifolia and negatively correlated with the vegetative phenophases of F. eximia. In despite of environmental seasonality, little seasonality in the phenology of two species was observed, especially in the reproductive phenology. Both species were important to frugivorous, but F. adhatodifolia can play a relevant role in the remnant.

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Abstract We analyzed the phenology of Ficus adhatodifolia Schott ex Spreng. (23 fig tree) and F. eximia Schott (12 fig tree) for 74 months in a remnant of seasonal semi-deciduous forest (23°27S and 51°15W), Southern Brazil and discussed their importance to frugivorous. Leaf drop, leaf flush, syconia production and dispersal were recorded. These phenophases occurred year-round, but seasonal peaks were recorded in both leaf phenophases for F. eximia and leaf flushing for F. adhatodifolia. Climatic variables analyzed were positively correlated with reproductive phenophases of F. adhatodifolia and negatively correlated with the vegetative phenophases of F. eximia. In despite of environmental seasonality, little seasonality in the phenology of two species was observed, especially in the reproductive phenology. Both species were important to frugivorous, but F. adhatodifolia can play a relevant role in the remnant.

Resumo Foi analisada a fenologia de Ficus adhatodifolia Schott ex Spreng. (23 indivíduos) e F. eximia Schott (12 indivíduos), por 74 meses em um remanescente de floresta estacional semidecidual (23°27S e 51°15W, centro de visitantes) no sul do Brasil e discutido sua importância para os frugívoros. Foram registradas as fenofases: queda e brotamento de folhas, produção e dispersão de siconios. Estas fenofases ocorreram ao longo do ano, porém picos sazonais foram registrados em abscisão e brotamento foliares para F. eximia e brotamento foliar para F. adhatodifolia. As variáveis climáticas analisadas foram positivamente correlacionadas com as fenofases reprodutivas de F. adhatodifolia e negativamente correlacionadas com as fenofases vegetativas de F. eximia. Apesar da sazonalidade ambiental, foi observada baixa variação sazonal na fenologia das duas espécies, especialmente na fenologia reprodutiva. Ambas as espécies foram consideradas importantes para os frugivoros, porém F. adhatodifolia pode desempenhar papel de destaque no fragmento florestal.

RESUMO

Abstract We analyzed the phenology of Ficus adhatodifolia Schott ex Spreng. (23 fig tree) and F. eximia Schott (12 fig tree) for 74 months in a remnant of seasonal semi-deciduous forest (23°27’S and 51°15’W), Southern Brazil and discussed their importance to frugivorous. Leaf drop, leaf flush, syconia production and dispersal were recorded. These phenophases occurred year-round, but seasonal peaks were recorded in both leaf phenophases for F. eximia and leaf flushing for F. adhatodifolia. Climatic variables analyzed were positively correlated with reproductive phenophases of F. adhatodifolia and negatively correlated with the vegetative phenophases of F. eximia. In despite of environmental seasonality, little seasonality in the phenology of two species was observed, especially in the reproductive phenology. Both species were important to frugivorous, but F. adhatodifolia can play a relevant role in the remnant.

Resumo Foi analisada a fenologia de Ficus adhatodifolia Schott ex Spreng. (23 indivíduos) e F. eximia Schott (12 indivíduos), por 74 meses em um remanescente de floresta estacional semidecidual (23°27’S e 51°15’W, centro de visitantes) no sul do Brasil e discutido sua importância para os frugívoros. Foram registradas as fenofases: queda e brotamento de folhas, produção e dispersão de siconios. Estas fenofases ocorreram ao longo do ano, porém picos sazonais foram registrados em abscisão e brotamento foliares para F. eximia e brotamento foliar para F. adhatodifolia. As variáveis climáticas analisadas foram positivamente correlacionadas com as fenofases reprodutivas de F. adhatodifolia e negativamente correlacionadas com as fenofases vegetativas de F. eximia. Apesar da sazonalidade ambiental, foi observada baixa variação sazonal na fenologia das duas espécies, especialmente na fenologia reprodutiva. Ambas as espécies foram consideradas importantes para os frugivoros, porém F. adhatodifolia pode desempenhar papel de destaque no fragmento florestal.

Assuntos

RESUMO

We analyzed the phenology of Ficus adhatodifolia Schott ex Spreng. (23 fig tree) and F. eximia Schott (12 fig tree) for 74 months in a remnant of seasonal semi-deciduous forest (23°27S and 51°15W), Southern Brazil and discussed their importance to frugivorous. Leaf drop, leaf flush, syconia production and dispersal were recorded. These phenophases occurred year-round, but seasonal peaks were recorded in both leaf phenophases for F. eximia and leaf flushing for F. adhatodifolia. Climatic variables analyzed were positively correlated with reproductive phenophases of F. adhatodifolia and negatively correlated with the vegetative phenophases of F. eximia. In despite of environmental seasonality, little seasonality in the phenology of two species was observed, especially in the reproductive phenology. Both species were important to frugivorous, but F. adhatodifolia can play a relevant role in the remnant.(AU)

Foi analisada a fenologia de Ficus adhatodifolia Schott ex Spreng. (23 indivíduos) e F. eximia Schott (12 indivíduos), por 74 meses em um remanescente de floresta estacional semidecidual (23°27S e 51°15W, centro de visitantes) no sul do Brasil e discutido sua importância para os frugívoros. Foram registradas as fenofases: queda e brotamento de folhas, produção e dispersão de siconios. Estas fenofases ocorreram ao longo do ano, porém picos sazonais foram registrados em abscisão e brotamento foliares para F. eximia e brotamento foliar para F. adhatodifolia. As variáveis climáticas analisadas foram positivamente correlacionadas com as fenofases reprodutivas de F. adhatodifolia e negativamente correlacionadas com as fenofases vegetativas de F. eximia. Apesar da sazonalidade ambiental, foi observada baixa variação sazonal na fenologia das duas espécies, especialmente na fenologia reprodutiva. Ambas as espécies foram consideradas importantes para os frugivoros, porém F. adhatodifolia pode desempenhar papel de destaque no fragmento florestal.(AU)

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Studies on intraspecific variation can contribute to the development of conservation strategies by identifying units of conservation for threatened species. Aspidosperma polyneuron is a tropical tree of seasonal semideciduous forests that is currently endangered and protected because it has been heavily logged for lumber, although it was once common in Brazil and neighboring countries. We investigated genetic structure in two samples of A. polyneuron collected from steep hillsides and from flat areas of a natural forest fragment in northern Paraná State, Brazil. Seven AFLP primer combinations yielded 200 markers, with a polymorphic rate of 88.5% for samples from the flat area and 99% for samples from the high declivity area. Total genetic diversity (H(T)) was 0.387, while the genetic diversity within the populations (H(S)) was 0.307 and 0.372, for samples from the flat and the high declivity areas, respectively. Genetic differentiation between samples was high, with a mean F(ST) of 0.265 and a genetic distance of 0.148, indicative of a high degree of genetic structure over a short distance. Principal coordinate analysis separated the samples into three groups of individuals; the first group included individuals from the high declivity area, the second group consisted of individuals only from the flat area, and the third group had individuals from both areas. Bayesian analysis also showed K = 3 clusters. The unexpected high level of intraspecific variation of A. polyneuron in this small forest fragment should be taken into account when evaluating the genetic impact of forest degradation on this species in other semideciduous forest fragments.

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Saplings of Aegiphila sellowiana were submitted to flooding and analysis of genetic diversity in order to investigate flooding tolerance as well as its genetic determination. This response is important because it means that some lines could be planted in degraded riparian areas. Leaves were sampled from each plant, and they were submitted to different flooding periods. Mortality of saplings was 40, 80, 50, 53.3, 33.3, and 33.3% in flooding for 15, 18, 25, 50, 80 days, and flooding for 50 days followed by re-aeration for 30 days, respectively. From the total number of flooded plants, 46.7% died in the first seven days of treatment, while 53.3% survived the flooding. The percentage of polymorphic loci (P(p)), Nei's genetic diversity (H) and the Shannon index (I) were slightly higher for the group that survived the stress of flooding (surviving: P(p) (%) = 67.48, H = 0.184, I = 0.287; not surviving: P(p) (%) = 66.67, H = 0.165, I = 0.261). Analysis of molecular variance showed that 5.88% of the genetic variability was due to the differences between groups of plants surviving and not surviving flooding, while 94.12% was due to genetic differences between individuals within these groups. Similar results were obtained by principal coordinate analysis. Based on these results, we can assume the existence of environment-specific genotypes and the genetic determination of flooding tolerance in A. sellowiana. Thus, some lines of A. sellowiana could be used in the reforestation of riparian habitats, especially in uplands along riverbanks.

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Knowledge of the effects of flooding on plant survival is relevant for the efficiency of management and conservation programs. Schinus terebinthifolius is a tree of economic and ecological importance that is common in northeast Brazil. Flooding tolerance and genetic variation were investigated in two riparian populations of S. terebinthifolius distributed along two different ecological regions of the Tibagi River basin. Flooding tolerance was evaluated through the investigation of young plants, submitted to different flooding intensities to examine the morphological and anatomical responses to this stress. The growth rate of S. terebinthifolius was not affected by flooding, but total submersion proved to be lethal for 100% of the plants. Morphological alterations such as hypertrophied lenticels were observed in both populations and lenticel openings were significantly higher in plants from one population. Genetic analysis using DNA samples obtained from both populations showed a moderate degree of genetic variation between populations (13.7%); most of the variation was found within populations (86.3%). These results show that for conservation purposes and management of degraded areas, both populations should be preserved and could be used in programs that intend to recompose riparian forests.

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The present work analyzes the lipid fraction from seeds of wild Ecuadorian Theobroma subincanum and selected commercial varieties of Theobroma cacao from Mexico (var. Criollo) and Ecuador (var. Arriba). The lipid fraction was obtained from the seeds through supercritical fluid extraction and analysis performed by preparatory thin-layer chromatography followed by gas chromatography. The results revealed that in T. subincanum the triglycerides contain fatty acids with longer chains. The melting point and peroxide and saponifiable numbers were determined for each Theobroma sample. The results lead to the conclusion that T. subincanum would produce a poorer quality butter than T. cacao. Nevertheless, the results do point toward a significant commercial use of T. subincanum for low-profile products.

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