Objetivou-se com esse trabalho estudar a influ?ncia da luz e da temperatura na
germina??o in vitro e ex vitro de sementes de Drosera latifolia, D. hirtella, D. montana
e D. schwackei, caracterizando morfologicamente as sementes e pl?ntulas, al?m de
desenvolver um protocolo para germina??o in vitro, desenvolvimento de plantas e
criopreserva??o de sementes de D. schwackei. Na caracteriza??o f?sica avaliou-se o
peso de mil sementes e o grau de umidade. Para a determina??o das caracter?sticas
morfol?gicas foram avaliadas a biometria das sementes e suas caracter?sticas externas.
Os testes de germina??o foram conduzidos in vitro e ex vitro, para cada esp?cie, por
meio de testes com quatro temperaturas constantes (15?C, 20?C, 25?C e 30?C), bem
como presen?a e aus?ncia de luz. Concluiu-se que as quatro esp?cies s?o sens?veis ? luz
e os melhores resultados de germina??o foram obtidos nas temperaturas de 20?C e 25?C.
Na segunda etapa do trabalho, realizou-se um ensaio de desinfesta??o com as sementes
de D. schwackei. Ap?s esse processo, as sementes de D. schwackei foram inoculadas
em diferentes concentra??es do meio de cultura MS (1/3, 1/2 e 100%) para a an?lise de
germina??o. Uma parte das pl?ntulas obtidas a partir do teste de germina??o foi
transferida para um novo meio de cultura, com diferentes concentra??es do meio MS
(1/3, 1/2 e 100%) para a indu??o do desenvolvimento. A outra parte das pl?ntulas foi
subcultivada em meio MS 1/3 dos sais, com diferentes concentra??es de BAP (0,0; 0,5;
1,0 e 1,5 mg.L-1), visando verificar a capacidade de multiplica??o do explante. Os
melhores resultados para a germina??o das sementes, desenvolvimento das pl?ntulas e o
cultivo in vitro de D. schwackei, foram obtidos utilizando-se o meio MS1/3 e MS1/2. J?
as baixas concentra??es de BAP favoreceram o crescimento das plantas in vitro, apesar
destas n?o promoverem brota??es. As pl?ntulas obtidas dos experimentos in vitro foram
aclimatizadas e o musgo Sphagnum foi o mais indicado. As sementes de D. schwackei
foram armazenadas em criotubos e imersas em botij?o contendo nitrog?nio l?quido e
mantidas por 1, 6, 12, 24, 48, 120 horas. A criopreserva??o n?o interferiu no
desenvolvimento e na morfologia das plantas em nenhum per?odo de armazenamento.Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico (CNPq)Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES)Funda??o de Amparo ? Pesquisa do Estado de Minas Gerais (FAPEMIG)Tese (Doutorado) ? Programa de P?s-Gradua??o em Produ??o Vegetal, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2019.The objective of this work was to study the influence of light and temperature on in
vitro and ex vitro germination of seeds of Drosera latifolia, Drosera hirtella, Drosera
montana and Drosera schwackei, to characterize seeds and seedlings morphologically,
also to develop a protocol for germination in vitro, plant development and
cryopreservation of D. schwackei seeds. In the physical characterization were evaluated,
one thousand seed weight and moisture content. For the determination of the
morphological characteristics the biometrics of the seeds, as well as their external
characteristics, were evaluated. Germination tests were conducted in vitro and ex vitro
for each species. Four constant temperatures (15?C, 20?C, 25?C and 30?C), presence and
absence of light were tested. It was concluded that the four species are light sensitive
and the best germination results were obtained at temperatures of 20?C and 25?C. In the
second stage of the work, a disinfestation test with D. schwackei seeds was carried out.
After disinfestation, D. schwackei seeds were inoculated in different concentrations of
MS culture medium (1/3, 1/2 and 100%) for germination analysis. Part of the seedlings
obtained from the germination test were transferred to a new culture medium, with
different concentrations of the MS medium (1/3, 1/2 and 100%), to induce development.
The other part of the seedlings were subcultured in MS medium 1/3 of the salts, with
different BAP concentrations (0.0, 0.5, 1.0 and 1.5 mg.L-1), aiming to verify the
multiplication capacity from explant. Best results for seed germination, seedling
development and in vitro cultivation of D. schwackei were obtained using MS1/3 and
MS1/2 medium. Low concentrations of BAP favored plant growth in vitro, although
they did not promote sprouts. Seedlings obtained from in vitro experiments were
acclimatized and Sphagnum moss was the most suitable. Drosera schwackei seeds were
stored in cryotubes and immersed in a canister containing liquid nitrogen and kept for 1,
6, 12, 24, 48, 120 hours. Cryopreservation did not interfere with plant development and
morphology in any storage period
