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Genipa americana L. has a diversity of secondary metabolites, including iridoids, phenolic compounds, and alkaloids. Pharmacological and biological properties have also been reported. This study has aimed to evaluate the chemical composition of the essential oil (EO) obtained from the leaves of G. americana and its bioactivity against Aceria guerreronis Keifer (Acari: Eriophyidae), a serious pest of coconut production areas worldwide. EO from the leaves was extracted and analyzed by Gas Chromatography-Mass Spectrometry and flame ionization detection (GC-MS/FID). For the bioassays, the adult coconut mites were subjected to increasing concentrations of EO. The analyses showed a predominance of sesquiterpenes, followed by monoterpenes, aldehydes, and fatty acids. The EO (LC50 = 0.41 mg mL-1; LC90 = 6.43 mg mL-1) showed toxicity and repellent effects against the coconut mite. The tested EO has the potential to develop as a natural product, with acaricidal activities against A. guerreronis, in order to assist in the control of the coconut mite.

Mangaba (Hancornia speciosa Gomes) is a native fruit of great economic, cultural, and environmental importance in its areas of occurrence. Due to extractive activities and real estate pressure, the number of natural populations has considerably decreased. The propagation of the species is still one of the primary obstacles for orchard implantations, thus, studies that provide a better understanding of the dynamics of the species’ growth should be developed. This work aimed to evaluate the biometry, emergence, and initial growth of mangaba progenies (Hancornia speciosa Gomes), using the plant material from the Active Germplasm Bank of Embrapa Coastal Tablelands, located in Itaporanga d’Ajuda, SE, Brazil. Treatments consisted of progenies from 17 accessions. The experiment was carried out in a completely randomized design with four replications of 25 seeds. Number of seeds per fruit, as well as fruit and seed weight (g), length (mm), width (mm), and thickness (mm) were evaluated. For emergence and initial growth, the following variables were analyzed: percentage of emergence (PE%), emergence speed index (ESI%), survival rate (SR%), height (H), stem diameter (SD), and the number of leaves (NL). Biometric analyses of fruits and seeds revealed significant phenotypic variability among mangaba accessions. Progenies of the accessions LGP1, LGP3, LGP4, PTP4, TCP2, TCP6, ABP1, ABP2, ABP4 and BIP4 showed better results for all emergence and initial growth variables. The progenies of accessions TCP1, BIP4, CAP5 and PRP5 expressed lower emergence and survival percentages, and low vigor.

Mangaba tree (Hancornia speciosa Gomes) is a tropical fruit species from Brazil and presents socioeconomic potential. The objective of this study was to determine antioxidant activity, rutin content and genetic similarity among in vivo and in vitro matrices and progenies of six accessions from the Mangaba Active Germplasm Bank of the Embrapa Coastal Tablelands, SE, Brazil. Young leaves of adult matrix plants and in vitro callus methanolic extracts obtained from young leaves resulted in differences between the accessions for the rutin content and high antioxidant activity. The Costa Azul accession, from Bahia, Brazil outstood with values above 3,000 g of dry extract/g of DPPH (2.2-diphenyl-1-picrilhydrazyl) in in vitro callus coming from nodal and internodal segments (3,023.73 and 3,136.80 g of dry extract/g of DPPH, respectively). Rutin was not found in extracts resulting from in vitro callus of mangaba tree. The difference among the values obtained for DPPH analysis are superior when compared with in vivo leaf extract, with the in vitro Costa Azul accession (nodal and internodal) outstanding, concluding that in vitro callus induction can interfere with chemical compounds of the plant. The markers detect genetic similarity under in vitro cultivation conditions. The Costa Azul accession group itself in isolation from others and EC50 concentrations differentiated between leaf and callus are obtained. O EC50 is superior in extracts deriving from in vitro callus, with the in vitro Costa Azul accession (nodal and internodal).

Azadirachta indica A. Juss, popularly known as neem, is a species native to India, belonging to family Meliaceae, considered the most important plant species with insecticidal action. The aim of this study was to evaluate the influence of growth regulators on induction and growth of neem callus and to observe their viability for embryogenesis through morpho-histological characteristics. In vitro germinated plants were used for excision of nodal explants. These segments were inoculated in Murashige and Skoog culture medium containing 1.0 mg/l 2,4-D (2,4-dichlorophenoxyacetic) combined with BAP (6-benzylaminopurine) at the following concentrations: 0.0, 0.5, 1.0 and 2.0 mg/l (T1, T2, T3 and T4 respectively), for callus induction. At 0 (mass of nodal segments without callus), 20, 40 and 60 days of culture, the percentage of callus formation was observed and the callus weight was measured for each treatment and at the end of the 60 days, consistency, color, and cell histology were evaluated. There was callus formation in all treatments tested. The highest induction of Azadirachta indica A. Juss callus is observed in the presence of 1.0 mg/l 2,4-D + 2.0 mg/l BAP, with callus showing light brown color, friable consistency and rounded cells with intense cell division, typical of cells with potential embryogenic capacity.

Drought is the most limiting environmental factor to crop productivity and presents a great variability in the degree of tolerance among and within species, among varieties. The aim of this study was to characterize sugarcane accessions regarding tolerance to water stress during in vitro cultivation based on changes in biometric, physiological and biochemical characteristics, within species and among species, to support future breeding programs. Adventitious shoots of five sugarcane accessions: Saccharum robustum, Saccharum spontaneum and Saccharum officinarum species, cultivated in Murashige and Skoog medium supplemented with 2% sucrose and 4 g/l Phytagel were used in five water potentials, 0, -0.3, -0.6, -0.9, -1.2 MPa, induced by mannitol. Survival, length of shoots and roots, number of shoots and roots, biomass, proline content in leaves and activity of antioxidant enzymes were analyzed. There is difference among species, and also, within the same sugarcane species when submitted to in vitro drought stress, and S. officinarum was shown to be the most tolerant. Proline can be used as a biochemical indicator of response to drought in sugarcane accessions and its accumulation was intensified in S. robustum and S. spontaneum accessions. Catalase activity remained unchanged with increased drought in sugarcane accessions evaluated.

Jenipapo (Genipa americana L. Rubiaceae) is a native species not endemic to Brazil and found in several biomes. The objective of this work was to evaluate the emergence and growth of seedlings cultivated in different substrates. Treatments were made of: T1 (fertilized soil), T2 (fertilized soil + coconut fiber), T3 (fertilized soil + sand), T4 (sand + coconut fiber), T5 (bovine manure + coconut fiber), and T6 (bovine manure + sand). The experiment consisted of a completely randomized design, with six treatments (substrates) and four replications of 25 seeds. The following variables were evaluated: first emergence count, percentage of emergence, emergence speed index, seedling height, root length, stem diameter, number of leaves, relative chlorophyll content (SPAD), leaf area, root dry matter, and shoot dry matter. The substrates T1 (fertilized soil), T2 (fertilized soil + coconut fiber), T3 (fertilized soil + sand) and T6 (bovine manure + sand) were more efficient for jenipapo seedlings production.

Mangaba (Hancornia speciosa Gomes) is a fruit species that is native to Brazil, and has social, economic and cultural importance. Knowledge of the genetic relationships between the remaining populations is essential in order to promote conservation strategies for these genetic resources. In the present study, it was evaluated the genetic diversity of 35 individuals from three remaining restingas areas in the states of Ceará (Iguape and Cascavel) and Pernambuco (Tamandaré), located in the Brazilian Northeast. Nine ISSR primers were used to determine the genetic variability. Sixty-one fully polymorphic fragments (100%) were generated. The largest (10) and smallest (5) number of fragments were obtained with the primers HB14 and HB12, respectively. The Shannon index (I = 0.40), the genetic diversity (H = 0.30), and the percentage of polymorphic loci (%P = 73.77%) were also estimated. Both the methods of UPGMA and the Principal Coordinates Analysis (PCoA) clustered individuals according to their place of origin. Genetic divergence was greater within population (64%) than between them (36%). This may indicate a strong genetic structure, i.e., the gene flow rate between populations is low, favoring inbreeding. ISSR markers were efficient for the analysis of genetic diversity, for the identification of clusters, and for the estimation of the genetic distance between and within populations.