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Slow-growth tissue culture allows in vitro conservation of plant genetic resources and is a complementary technique to conventional preservation methods. The objective of this study was to evaluate the effect of the culture medium supplemented with sucrose, mannitol and sorbitol osmotic agents on the induction of in vitro slow growth of A. cearensis, seeking to establish alternative techniques for ex situ conservation of the species. Plants with age of 10 days were inoculated in woody plant medium (WPM) supplemented with different concentrations of sucrose (87.64, 131.46, 175.28 or 262.92 mM) combined with mannitol or sorbitol at varying concentrations (0.0, 43.8, 65.73, 87.64 or 131.46 mM), solidified with 0.7% agar. The following parameters were evaluated: survival percentage, number of senescent leaves, aerial part length, root length, aerial part dry mass, root dry mass; and number of shoots. The conservation of A. cearensis was viable for up to 300 days in WPM supplemented with 262.92 mM of sucrose or the combination of 87.64 mM of sucrose with 43.80 mM of mannitol, because besides achieving a survival percentage greater than 55.0%, the plants conserved in these media presented normal development and the best appearances, with predominance of uniform green leaves during the storage process.

Banana (Musa spp.) is one of the main fruits consumed worldwide. However, finger drop, is a physiological disorder that causes many postharvest problems, which eventually reduces market value and consumer acceptance. Therefore, the objective of the study was to evaluate the anatomical changes that occur in the pedicel rupture area (drop zone) of bananas diploids (BB França) and tetraploid (BRS Pioneira) in three ripening stages. The levels of gene expression involved in the natural ripening process and in the development of finger drop, was also investigated. The accumulation of their mRNAs and those of expansin (EXP1), pectate lyase (PEL1) and xyloglucan endotransglucosylase/hydrolase protein (XTH4) genes already isolated from bananas were measured by quantitative polymerase chain reaction in three ripening stages. BB França presented a higher resistance to finger drop due to the presence of some specific morphoanatomical characteristics, such as larger parenchymal cells and greater deposition of lignin. In contrast, there was degeneration of the pedicel parenchymal tissue of the BRS Pioneira genotype, forming large empty spaces during the ripening of the fruits, mainly in stage 6, which contributed to the finger drop. The diploid BB França  is a strong candidate for use in  banana breeding programs aimed at fruit drop resistance. This will certainly improve the quality of banana varieties. Moreover, PEL1 proved to be an excellent candidate gene for functional studies of finger drop in bananas.

Knowledge about the behavior of seeds is important to support studies to minimize the effects of predatory extractivism on ornamental bromeliads. The aim of this study was to evaluate the germination, seed morphology and post-seminal development of Hohenbergia belemii and Neoregelia compacta (Bromeliaceae) in different substrates. Seeds were disinfested with a sodium hypochlorite solution and germinated in four substrates: germitest paper; washed sand; vermiculite; and the commercial substrate Plantmax®. The experimental design was completely randomized in a 2 x 4 factorial scheme, with four repetitions and 50 seeds per repetition. The seeds were sown on the substrates and stored in plastic Gerbox® boxes, which were kept in BOD chambers with 12 hours photoperiod at constant temperature of 30ºC. Data were collected daily to calculate germination percentage and growth performance. The germination started on the 4th day after sowing (DAS) for H. belemii, with stabilization on the 11th DAS, while this occurred from the 5th DAS for N. compacta with stabilization on the 21st DAS. Germination was classified as development of epigeal and cryptocotylar seedlings for both species. The vermiculite substrate had a significant effect on seed germination, GSI (germination speed index) and growth of seedlings of both species. Our findings can support future research on seed technology and also contribute to better knowledge of the evolution of morphological characters of these bromeliad species.

Amburana cearensis is an arboreal legume of the Fabaceae family, with high phytotherapic and medicinal potential due the presence of secondary metabolites. The objective of this study was to evaluate the effect of 2,4-dichlorophenoxyacetic acid (2,4-D) and 4-amino-2,5,6- trichloro-2-pyridinecarboxylic acid (picloram) on the in vitro induction of callogenesis of A. cearensis and analyze the biochemical and phytochemical potential of these calluses. For callus induction, leaf and cotyledon segments were used as explants, which were inoculated in woody plant medium (WPM) supplemented with different concentrations of 2,4-D (0, 5, 10, 20, 40 μM) or picloram (0, 5, 10, 20, 40, 80 μM). The callus growth curve was estimated based on fresh weight, measured at 7-day intervals until 28 days after inoculation. The calluses were analyzed by biochemical tests to quantify the reducing sugars and total proteins. Phytochemical screening and high-performance liquid chromatography were performed to establish the phytochemical profile of extracts from calluses. The concentrations of 21.94 μM and 26.46 μM of 2,4-D induced the greatest formation of compact and friable calluses from the leaf and cotyledon segments, respectively. The growth curve had two distinct phases (lag and exponential) for both types of calluses evaluated. The maximum levels of reducing sugars and total proteins in the calluses from leaf and cotyledon segments were obtained on the day of inoculation and after 28 days of cultivation, respectively. The results of the phytochemical analysis identified the presence of coumarin in all the extracts evaluated, this secondary metabolite has high pharmacological potential.

The objective of this work was to characterize the morphology and viability of the pollen of 15 genotypes of castor bean (Ricinus communis L.) and to generate information that can assist in the selection of highly promising male parents for future use in genetic improvement programs aimed at producing seeds for oil extraction. Acetolysis and scanning electron microscopy was used to characterize the morphology of the pollen. The viability of the pollen grains was estimated by in vitro germination and colorimetric analysis (acetocarmine 2% and 2, 3, 5-triphenyltetrazolium chloride 1%). For the in vitro germination, pollen grains were grown in 10 types of solidified culture medium consisting of different concentrations of sucrose, boric acid, calcium nitrate, magnesium sulfate and potassium nitrate. The pollen grains had the following characteristics: medium size, isopolar and subspheroidal shape, radial symmetry, circular ambit, 3-colporate, elongated endoapertures, tectate exine and granulated sexine. The acetocarmine dye overestimated pollen viability. The media M5 and M8 were the most efficient at promoting the germination of pollen grains. The studied genotypes had high levels of viability and can therefore be used as male parents in genetic improvement programs.

The objective of this study was to evaluate the influence of pH on in vitro germination and pollen grain viability of banana diploids (AA) generated by the breeding program of Embrapa Mandioca e Fruticultura Tropical. The pollen grains were inoculated in culture medium containing 15% sucrose, 0.01% H;BO;, 0.01% KNO;, 0.03% Ca(NO;)>.4H20, 0.02% MgS04.7H,0, solidified with 0.8% agar and pH adjusted to 5.8 or 7.0. Pollen viability was evaluated by staining with 1% acetic carmine. The germination percentages of the genotypes 9187-0] (90.0%) and M-53 (89.7%) in pH 7.0 medium were highest, while the pollen tube length of genotype 9187-01 was approximately half the size (1.79mm) of genotype M-53 (3.84mm). The pollen viability of the genotypes evaluated was higher than 85%, even for the diploids with a low in vitro germination percentage.

New banana varieties with superior agronomical characteristics have been developed through introductionand/or genetic breeding. In order to guarantee its marketing and intellectual property, these new varieties need to becharacterized by efficient inheritable qualitative morphological and molecular descriptors. The aim of the research was tocharacterize recommended banana varieties using qualitative morphological and molecular descriptors. Twelve genotypeswere analyzed using 61 morphological descriptors where 17 were related to the plant, 24 to the bunch and 20 regarding theflower. Eighty-one molecular markers; 47 RAPD primers and 34 SSR primers were used. The morphological and moleculardescriptors were efficient in the characterization and identification of specific characteristics for most of the varieties evaluated.Plant and inflorescence descriptors presented the greatest variability of characteristics that can facilitate its use for cultivarprotection and registration

The semiarid region of Brazil is marked by scarce rainfall and high temperatures. The Caatinga biome, established in this region, has great diversity of plants with economic potential and applications, such as in herbal medicine. Plant representatives include those of the family Lamiaceae, which has 240 genera and 7200 species. The essential oil of the species Medusantha martiusii , popularly known as “alfazemas de caboclo”, has often been found to have biological activities, such as cytotoxic, antimicrobial and insecticidal effects, thus making this species economically important. The objective of this study was to characterize the climatic, geographical and edaphic aspects of sites where M. martiussi naturally occurs in the state of Bahia in order to understand the possible relationships and interactions between the environment and plant growth, development and production of essential oils. Vector files with climate, geomorphology, phytophysiognomy, and soil data were examined and the data were systematized and analyzed. The species occurs in semiarid areas with nutrient-poor, acidic and well-drained soils. The species has broad range of thermal adaptation, occurring from mountainous regions with high relief to low altitudes and in climatic zones characterized by scant and poorly distributed rainfall. The essential oil content showed a quantitative variation across the surveyed sites, with an average of 2.07% by dry weight of leaves and flowers, and a moderate and significant interaction of the essential oil with Fe and Zn concentrations present in the soil were also observed.

Eplingiella fruticosa, popularly known as “alecrim-de-vaqueiro”, is an aromatic and medicinal plant of the Lamiaceae family, endemic to the coastal region of northeastern Brazil. The objective of this study was to evaluate, in 12 genotypes of E. fruticosa , the variation of 16 morpho-agronomic markers related to the plant and leaves, as well as to identify the phytochemical compounds present in the essential oil (EO) of this species. The essential oil was obtained from dry leaves by hydrodistillation and analyzed by gas chromatograph coupled to mass spectrometer and a flame ionization detector (GC–MS/FID). The data were evaluated using multivariate analysis via the unweighted pair group method with arithmetic mean (UPGMA) for hierarchical clustering with canonical variables. Based on the morpho-agronomic data obtained, the formation of at least three groups was observed. The characteristics that most contributed to the formation of the groups were left petiole length, fresh leaf weight and leaf length. The genotypes EF002, EF003, EF005 and EF012 stood out by presenting greater genetic distances, indicating good potential for use in breeding programs aimed at foliar biomass production. A total 15 constituents were identified in the EOs, of which (E)-caryophyllene, bicyclogermacrene and α-pinene were the main components of all genotypes. Diversity classification based on chemical composition of EOs put them into groups. The highest detected components in the respective genotypes were: Group 1, represented by seven genotypes, containing (E)-caryophyllene (8.61–13.15%) and bicyclogermacrene (7.15–13.25%) as major compounds; Group 2, consisting of two genotypes, with (E)-caryophyllene (14.42–16.36%) and bicyclogermacrene (16.96–19.82%) as major compounds; Group 3, represented by two individuals, with highest production of (E)-caryophyllene (13.86–14.98%); and Group 4, with only one genotype, containing α-pinene (12.0%) as the major compound. The results of the present study can contribute to a better understanding and management of conservation and breeding of E. fruticosa germplasm. In addition, the results show the potential of the essential oils of this species and their major compounds for the development of new pharmaceutical products.

The present study evaluated the population structure and genetic diversity using inter simple sequence repeat (ISSR) markers in 18 natural populations belonging to three species of Eplingiella ( E. cuniloides, E. fruticosa and E. brightoniae ), found growing naturally in the semiarid region of Northeast Brazil. Samples of 265 plants were analyzed using nine primer combinations, which generated 131 informative bands. Eplingiella spp. populations showed moderate genetic diversity (percentage of polymorphic bands, PPB = 75.6–96.9%, Nei's genetic diversity He  = 0.31–0.39, Shannon's information index I  = 0.33–0.48). Molecular variance analysis revealed that within populations, variations contributed more (74%) to the genetic diversity than between population variations (26%), with percentage of the genetic differentiation coefficient ( G ST  = 0.29). The mean value of F ST was 0.175, demonstrating good differentiation between populations. The analysis of the structure by the Bayesian method revealed the formation of two groups (K = 2), with many migrant individuals and a high level of miscegenation. The hierarchical cluster dendrogram grouped the 18 populations into two major clusters, with good support for the main clades (100%). According to principal component analysis, the two main principal components explained 21.06% of the total variation. The ISSR markers used were effective in identifying the variability of natural populations of Eplingiella spp., and population structure demonstrated recent diversification of species. The results shed more light on the genetic variation and evolutionary dynamics of Eplingiella , helping to formulate effective breeding strategies.