RESUMEN
Pfaffia glomerata ocorre em vários estados do Brasil e países limítrofes da região Sul às margens de rios e nas orlas das matas de galerias, é espécie hidrófita e heliófita. As raízes de espécies do gênero Pfaffia são usadas na medicina popular brasileira, especialmente como tônico, afrodisíaco e no controle do diabete. O objetivo deste trabalho foi estabelecer um banco de germoplasma in vitro de Pfaffia glomerata. O experimento em delineamento inteiramente casualizado foi conduzido com seis tratamentos: 1) MS + 2 por cento de sacarose + 4 por cento de sorbitol; 2) MS/2 + 2 por cento de sacarose + 4 por cento de sorbitol; 3) MS + 2 por cento de sacarose + 4 por cento de sorbitol + 2 mg L-1 de pantotenato de cálcio; 4) MS/2 + 2 por cento de sacarose + 4 por cento de sorbitol + 2 mg L-1de pantotenato de cálcio; 5) MS + 2 por cento de sacarose + 3 por cento de manitol + 2 mg L-1de pantotenato de cálcio; 6) MS/2 + 2 por cento de sacarose + 3 por cento de manitol + 2 mg L-1de pantotenato de cálcio. Os resultados obtidos foram submetidos à análise de variância e ao teste de separação de médias de Scott Knott. Os tratamentos um, três e quatro apresentaram, significativamente, o maior número de segmentos nodais por haste, quando comparados com os tratamentos dois, cinco e seis. O tratamento dois foi o mais indicado para a conservação in vitro da espécie por ter promovido menor crescimento das plantas (altura de 3,1±1,9 cm), alto índice de sobrevivência, 100 por cento de explantes com brotação e o maior número de brotos por explante, após seis meses de cultivo. Todas as plântulas produziram raízes e não houve formação de calos, também não ocorreu hiperhidricidade nos tratamentos avaliados. As plantas aclimatizadas apresentaram 100 por cento de sobrevivência no ambiente ex vitro. A manutenção de acessos de P. glomerata no banco de germoplasma in vitro é viável tanto do ponto de vista da conservação quanto economicamente.
Pfaffia glomerata occurs in several states of Brazil and its neighboring countries in the south region at riverbanks and gallery forests. It is a hydrophyte and heliophyte species. The roots of the genus Pfaffia are used in Brazilian folk medicine especially as tonic, aphrodisiac and to control diabetes. The aim of this work was to establish an in vitro germplasm bank for Pfaffia glomerata. The experiment was carried out in completely randomized design with six treatments: 1) DM + 2 percent sucrose + 4 percent sorbitol; 2) DM/2 + 2 percent sucrose + 4 percent sorbitol; 3) DM + 2 percent sucrose + 4 percent sorbitol + 2 mg L-1 calcium pantothenate; 4) DM/2 + 2 percent sucrose + 4 percent sorbitol + 2 mg L-1 calcium pantothenate; 5) DM + 2 percent sucrose + 3 percent mannitol + 2 mg L-1 calcium pantothenate; 6) DM/2 + 2 percent sucrose + 3 percent mannitol + 2 mg L-1 calcium pantothenate. Results were subjected to analysis of variance and Scott Knott test for mean grouping. Treatments 1, 3 and 4 had a significantly larger number of nodal segments per stem, compared to Treatments 2, 5 and 6. Treatment 2 was the most appropriate for the in vitro conservation of this species since it led to the lowest growth (3.1±1.9 cm height), high survival rate, 100 percent explants with sprouting, and the largest number of sprouts per explant after six months of culture. All seedlings produced root and showed no formation of calluses or hyperhydricidity under the evaluated treatments. Acclimatized plants showed 100 percent survival in the ex vitro environment. Maintaining P. glomerata accessions in an in vitro germplasm bank is viable both economically and for conservation.
Asunto(s)
Amaranthaceae/genética , Crecimiento/fisiología , Técnicas In Vitro , Medios de Cultivo/análisis , Brotes de la Planta/anatomía & histología , Brotes de la Planta/citología , Brotes de la Planta/genética , Bases de Datos GenéticasRESUMEN
An efficient clonal propagation procedure for six rice varieties cultivated in Argentina was developed by using shoot tip cultures, and the genetic stability of the micropropagated plants was verified by isozyme analysis. One week old seedlings obtained on MS medium were sectioned and subcultured on MS medium (0.75% agar) supplemented with different combination and concentrations of cytokinins (BAP and KIN) and auxins (2,4-D and NAA). After four weeks of culture, multiple shoots were obtained. The best response was observed on MS supplemented with BAP 5 mg l(-1). Shoot clumps were multiplied in MS liquid medium containing BAP 5 mg l(-1). Profuse rooting was obtained after transfer to MS medium lacking growth regulators and with sucrose 8% (w/v). Complete plants were successfully transferred to soil and grown to maturity. ADH and EST patterns of micropropagated rice plants showed polymorphisms compared with plants of the original varieties. However, the zymograms of the seed derived progeny of the micropropagated plants were similar to that of the original varieties. These results indicate the maintenance of the genetic stability in the sexual progeny of micropropagated plants.