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Plants endue a key role against illnesses caused by oxidative stress. These attributes are frequently associated with polyphenolic compounds. However, presence and concentration of secondary metabolites are affected by abiotic factors. The in vitro culture techniques can solve these drawbacks. Peppers can be a suitable alternative to obtain polyphenols. Aiming to optimise the callus culture stage from Capsicum baccatum to produce polyphenols, this work evaluated systemically the effects of the explant's origin (root, hypocotyl and cotyledon), growth hormone type (2,4-dichlorophenoxyacetic acid (2,4-D), benzylaminopurine (BAP) and a combination of 2,4-D/BAP at five-to-one ratio) and concentration (0.023-10.000 mg L) on callus culture efficiency parameters using a multilevel factorial design. The root explant in combination with BAP at 1.138 mg L ensured the optimal values of the assessed responses; ​callus mass (225.03 mg), antioxidant activity (35.95%), total phenols (11.48 mg of GAE/g DE) and flavonoids (15.92 mg of RU/g DE) production.

The Capsicum genus comprises hundreds of varieties with fruits that differ widely in shape, size, color, and flavor. The Brazilian cuisine consumes Capsicum baccatum L. (pepper) extensively and few reports about chemical composition and biological properties about this pepper were published. The present study determined four factors numeric effects on germination in vitro of this specie, among them, the solution type for osmotic conditioning (water and 1% KNO3 aqueous solution), germination medium (agar and agar + gibberellic acid at 1.88 mgL -1 ), post-seeding time (15 and 30 days) and two genotypes (Pitanga and Cambuci) on two germination parameters (germination and cotyledon emerging rates), as first step for establishing a cell suspension culture to produce secondary metabolites. The methodology was a two-level full factorial experimental design (2 4 ). The results allowed polynomial equations definition which describes the germination phenomena as a function of the four factors under study. The genotype responses to osmotic conditioning and germination medium were different. The optimal combination of treatments for in vitro germination and development of seedlings for Pitanga and Cambuci was water + agar and water + agar-GA3, respectively.

Orchids are valued as ornamental plants, bioindicators, and medicinal plants, which implies that some species may be over-collected. Some inhabit very fragile environments and are under threat by the misuse of habitats and anthropogenic impacts. The search for beautiful plants and flowers has increased the number of facilities for micropropagation either by seeding or by cloning plants using in vitro techniques. However, not all species have appropriate media for growth and development that would help in conservation efforts. Cyrtopodium aliciae is an endemic species of rupestrian grassland in Brazil t. It has appeal as an ornamental plant or for use in hybridisation programs dueo its small size and white brownish-purple dotted flowers. This study compared three different media, namely ½ concentration Murashige and Skoog (MS), Vacin and Wendt, and Knudson C, during plant growth and their effect on the acclimatization of Cyrtopodium aliciae. The number and length of shoots and roots, increase in mass, and survival in vitro and ex vitro were analyzed. The experiment was conducted as completely random with a factorial arrangement of treatments (3 × 3) with 10 repetitions per treatment containing 10 plants for the in vitro experiment and 3 repetitions of 10 plants for the ex vitro experiment. Cyrtopodium aliciae performed better in the ½ concentration MS medium with a higher increase in mass, plant development, and survival under both in vitro and ex vitro conditions.

In vitro cultivation strategies promise conservation and micropropagation of vulnerable or economically exciting plants, especially in Orchidaceae. Numerous reports are available for an extensive contingent of orchids of the most varied genera, and the main issue is related to the behavior of species during the process of germination and growth concerning the nutrients used in the culture media. In Orchidaceae, several evidence support that each species responds differently and specifically according to the biotic and abiotic conditions available for in vitro growth. The main concern is to seek simplified culture media that promote germination and the development of healthy plants on a large scale. This study assessed the behavior of Catasetum fimbriatum and Catasetum macrocarpum in culture media containing commercial fertilizers supplemented with organic additives, compared with traditional media, an economically more viable strategy for micropropagation. Seeds were cultured on traditional nutrient media or with commercial fertilizer and organic additives in different combination. The analysis of plant growth after 120 days in vitro showed that the best treatment in both species was the medium containing commercial foliar fertilizer Peters NPK ® 10:30:20 supplemented with potato and banana pulp.

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The orchids are known for its beautiful flowers, the genetic recombination ability and the lack of its defined taxonomic classification of the Orchidaceae family. Phylogenetic studies using molecular technics allow additional taxonomy understanding. ISSR molecular markers can determine the phylogenetic relationships among species and individuals of the same species. In this study the patterns of polymorphism were compared in subjects of Cattleya guttata, C. tigrina and C. leopoldii in order to find variations in the germplasm which can contribute to elucidate phylogenetic issues. Results were obtained using 13 primers in ten subjects of each species. They increased 97 loci being 96.9% polymorphic for the three studied species. It is concluded that the protocol was effective for the identification of fragments in all studied species. The analysis of total banding pattern suggests that C. guttata and C. leopoldii are molecularly related to each other and more distant from C. tigrina.

Asymbiotic germination techniques are successful in species of the Catasetum genus. The diverse composition of the culture media can be critical; however, viable seeds are required for asymbiotic germination. The reliable method for viability assessment is the tetrazolium test. A decisive step in the efficiency of the tetrazolium test is the seeds preconditioning with sucrose solution, which has the potential to improve germination. Therefore, this work aimed to evaluate the seed germination of three species of the genus Catasetum in culture media, preconditioned or not with sucrose solution. Seeds of the species Catasetum osculatum, Ctsm. galeritum and Ctsm. complanatum were assessed by tetrazolium test and germinated in two different media, pretreated or not with 10% sucrose solution. The statistical analysis showed that the use of sucrose pretreatment significantly increased the germination rates of the species. We conclude that the pretreatment with 10% sucrose for 24 hours, regardless of the species and the culture medium, significantly increases the germination of Ctsm. complanatum, Ctsm. galeritum and Ctsm. osculatum seeds.