ABSTRACT. The objective of this study was to determine the silicon concentration that would provide good growth in passion fruit plants. Passion fruit seeds were sown in polystyrene. After 60 days, when they were approximately 15 cm tall, the plants were transplanted into polyethylene pots containing 1.1 kg Tropstrato® substrate. Treatments consisted of four concentrations (0, 0.28, 0.55, and 0.83 g pot -1 ) of silicon applied as a silicic acid solution 1%. This solution was applied around the stem of the plants (drenched), with the first application being administered 15 days after transplanting. In total, three applications were made at intervals of 15 days. After the last application, the plants were subjected to chemical analysis to determine the silicon concentration and to X-ray microanalysis and flow cytometry. Phytotechnical analyses were performed during the applications. The use of silicon in concentrations of 0.28 and 0.55 g pot -1 provides better growth of the passion fruit, and the absorption and deposition of the silicon in the passion fruit leaves are proportional to the availability of this element in the plant. The roots of the passion fruit plant are silicon accumulators, and the DNA stability and amount are preserved in the silicon-treated passion fruit plants. ) de silício, na forma de solução de ácido silícico a 1%. Esta solução foi aplicada ao redor do caule das plantas (drench), sendo a primeira aplicação realizada 15 dias após o transplantio das plantas. No total, foram realizadas três aplicações, em intervalos de 15 dias. Após a última aplicação, as plantas foram submetidas à análise química de concentração de silício, microanálise de raios-X e citometria de fluxo. As análises fitotécnicas foram realizadas no decorrer das aplicações. O uso do silício nas concentrações 0,28 e 0,55 g vaso -1 , proporciona melhor crescimento das plantas de maracujazeiro, a absorção de silício e sua deposição nas folhas de maracujazeiro são proporcionais à disponibilidade desse elemento para a planta, o maracujazeiro é uma planta acumuladora de silício nas raízes e a estabilidade da quantidade de DNA é preservada nas plantas de maracujazeiro tratadas com silício.Palavras-chave: citometria de fluxo, ácido silícico, Passiflora edulis.

RESUMOA pitaia vermelha de polpa branca (Hilocereus undatus) é uma cactácea, pertencente ao grupo das frutíferas tropicais, considerada promissora para o cultivo. Objetivou-se induzir calos e determinar o potencial embriogênico e a estabilidade genética em pitaia. ); 2 a ) Curva de crescimento de calos, por vários períodos de tempo (0, 7, 14, 21, 28, 35, 42, 49, 56, 63, 70, 77, 84, 91, 98, 105 Callus induction, embryogenic potential and genetic stability in red pitaya ABSTRACTThe red pitaya with white pulp (Hilocereus undatus) is a cactus belonging to the group of tropical fruit, considered promising for cultivation. This study aims to induce callus and embryogenic potential and determine the genetic stability in pitaya. The study was divided into four steps: 1ª) Callus induction using doses of 2,4-D (2.0 and 4.0 mg L -1 ) and with doses of glutamine (100 and 200 mg L -1 ); 2ª) callus growth curve for various time periods (0, 7, 14, 21 , 28, 35, 42 , 49, 56, 63 , 70, 77, 84 , 91, 98, 105 and 112 days); 3ª) Cytochemical analysis to assess the potential of embryogenic callus (samples consisting of 100 mg of callus) and 4ª) Analysis of flow cytometry to assess the genetic stability of the callus (compared with a seedling in vitro -control). The conclusion is that the 4.0 mg L -1 2,4-D is the best concentration for callus induction in explants shoots of pitaya; the glutamine does not influence the callus formation. The callus has higher embryogenic potential at 49 days, therefore must be spiked in this period. By flow cytometric was detected endoreduplication in the material analyzed.

Curcuma longa L., from the Zingiberaceae family, generally reproduces through its rhizomes, which are also utilized for therapeutic purposes because they are rich in terpenoids. Its conventional propagation has low efficiency due to the small number of seedlings and their contamination by pathogens. Therefore, this study aimed to evaluate the influence of growth regulators on the development of in vitro-cultivated C. longa as well as to determine their influence on DNA content and foliar anatomy. Shoots were inoculated in MS culture medium with the addition of 30 g/L of sucrose and 6.5 g/L of agar, and a pH adjusted to 5.8. Two assays were built to study the multiplication and rooting phases of growth. The first assay evaluated the influence of eight concentrations of cytokinins and auxins on the multiplication phase. Leaf samples were analyzed for DNA content through flow cytometry, utilizing two reference standards, green pea, and tomato. Characteristics of leaf anatomy were also measured in four time periods. The second assay analyzed the influence of six auxin concentrations on the rooting phase. The first assay showed that the root systems grew more in treatment 3 (4.44 µM benzylaminopurine [BAP], 0.46 µM kinetin [KIN]) and reached greater dry mass in T8 (8.88 µM BAP, 0.92 µM KIN, 2.16 µM naphthalene acetic acid [NAA]). The largest fresh matter of the main shoot was found in T2 (4.44 µM BAP). The estimated DNA content varied depending on the presence of supplemental growth regulators, from 2.38 to 2.77 pg, and was greater in T4 (4.44 µM BAP, 1.08 µM NAA) and T5 (4.44 µM BAP, 0.46 µM KIN, 1.08 µM NAA). Results from the latter two treatments were not significantly different. Estimates of DNA content were precise, as indicated by coefficients of variation that were much lower than 5%. The results also showed quantitative variation of evaluated anatomical traits. In general, there was a thin epidermis layer with rectangular cells, followed by parenchyma with octahedral cells and differentiated xylem and phloem. In leaf parenchyma, the presence of idioblasts containing phenolic compounds was observed in all growth stages. In the rooting phase, the supplementary auxins affected the dry matter of the aerial part and roots. The highest averages were observed in treatments with 2.0 µM NAA.

The jelly palm plant [Butia capitata (Martius) Beccari] is a native palm of the Cerrado biome used for many purposes in northern Minas Gerais State, Brazil. Dormancy is common in palm seeds, resulting in slow and uneven germination that may take years to complete. Modification in the growth pattern, anatomical parameters, physiological and biochemical characteristics of the plant can be verified due to changes in the light spectrum transmitted through colored shade nets used. Therefore, the objective of this study is to evaluate the effect of colored shade nets on the leaf and root anatomy of the jelly palm plant. The experiment was performed in a completely randomized design, with five treatments, ten replicates and eight plants per replicate, totaling 400 plants. Four colored photo-converter nets with 50% shading and different radiation proportions were employed: white (985 μmol.m-2.s-1), red (327 μmol.m-2.s-1), black (433 μmol.m-2.s-1) and silver (405 μmol.m-2.s-1). The plants cultivated under direct sunlight (1000 μmol.m-2.s-1) were considered as the control group. Leaf and root anatomical analysis was performed on 10 plants per treatment. It is possible to conclude that the colored shade nets caused changes in leaf and root anatomy of the jelly palm plant (Butia capitata).

The objective of this work was to evaluate the induction of indirect organogenesis by concentrations of dichlorophenoxyacetic acid (2,4-D) and thidiazuron (TDZ) in pitaya (Hylocereus undatus) explants, using scanning electron microscopy and the flow cytometry technique. The treatments consisted of the concentrations of 0, 2.0, and 4.0 mg L-1 2,4-D and TDZ and of the combinations of these regulators. Percentages of callus coverage at 45 and 60 days were evaluated. The explants subjected to the treatments were analized by flow cytometry and scanning electron microscopy. All treatments induced endoreduplication, and there was no somaclonal variation. Under the combination of 2.0 mg L-1 TDZ and 4.0 mg L-1 2,4-D, calluses were formed in 95% of the explants, but were smaller than those produced with 2,4-D separately. The concentration of 2.0 mg L-1 TDZ induces the indirect organogenesis in pitaya explants, confirmed by the presence of conducting vessels through scanning electron microscopy.