Paclobutrazol in the in vitro conservation of cassava genotypes

In vitro germplasm conservation allows to extend the interval between subcultures without compromising the viability and genetic integrity of the plant, ensuring a backup of genotypes with high phytosanitary quality. Thus, this study aimed to verify the effect of four concentrations of Paclobutrazol® in inducing minimum growth in five Manihot esculenta accessions from the in vitro Active Germplasm Bank of Embrapa Cassava and Fruits. An experiment was installed using the Murashige and Skoog medium without addition and added with four concentrations of Paclobutrazol® (0.10, 0.20, 0.30, and 0.40 mg L-1), in five in vitro accessions of M. esculenta: BRS Jari (BGM 2041), Cigana (BGM 0264), BRS Poti Branca (BGM 2017), TME 14, and BRS Novo Horizonte. The statistical design was completely randomized in a 5 x 5 factorial scheme, with 15 repetitions. After 120 days of cultivation, the following variables were evaluated: plant height (cm), number of green leaves, number of senescent leaves, number of mini-cuttings, number of shoots, and fresh and dry mass of shoots and roots (mg). Paclobutrazol® caused a reduction in plant height and gain in root mass for all accessions, in addition to preserving the number of green leaves and decreasing leaf senescence for most genotypes. There was a strong dependence of the genotype in relation to the concentration of Paclobutrazol®. The concentration of 0.20 mg L-1 showed potential in the in vitro conservation of M. esculenta genotypes.(AU)

In vitro conservation of 'Florida Rough' lemon plants / Conservação in vitro de plantas de limoeiro 'Rugoso da Florida'

The establishment of minimum growth conditions is essential for in vitro germplasm conservation. Changes to the basic medium and carbon source concentrations are important factors for reducing plant growth in vitro. This study adjusted a protocol for the in vitro conservation of 'Florida Rough' lemon plants. Microcuttings (approximately 1 cm) from plants that were previously cultivated in vitro were inoculated into test tubes with 10 mL of woody plant medium (WPM) at different concentrations (1/1, 1/2 and 1/4) and supplemented with 0, 12.5, 25 and 50 g.L-1 of sucrose, solidified with 7 g.L-1 agar and adjusted to pH 5.8. The experiment was completely randomized in a 3 x 4 factorial design with 15 replications and was maintained under controlled conditions for 360 days. After this period the plant height in cm (PH), the plant dry mass in g (PDM) and the 21 numbers of green leaves (NGL), senescent leaves (NSL) and microcuttings (NM) were evaluated. The variables that best explained the observed behavior of the 'Florida Rough' lemon plants were NGL and PH, with values of 61.63 and 35.08%, respectively. The original concentration of the WPM with the addition of 25 g. L-1 of sucrose yielded the best 'Florida Rough' lemon plant growth reduction in vitro while maintaining the physiologically health of the plants.

O estabelecimento de condições de crescimento mínimo é fundamental para a conservação in vitro de germoplasma. Alterações nas concentrações do meio básico, na fonte de carbono, são fatores importantes na desaceleração do crescimento de plantas in vitro. Este trabalho teve como objetivo ajustar um protocolo de conservação in vitro de plantas do limoeiro 'Rugoso da Flórida'. Microestacas de plantas previamente cultivadas in vitro, com aproximadamente 1 cm, foram inoculadas em tubos de ensaio contendo 10 mL do meio de cultura WPM em diferentes concentrações (1/1, 1/2 e 1/4), suplementado com 0; 12,5; 25 e 50 g.L-1 de sacarose, solidificado com 7 g.L-1 de ágar e o pH ajustado em 5,8. O experimento foi instalado em delineamento inteiramente casualizado com 15 repetições, em esquema fatorial 3 x 4, e mantido sob condições controladas durante 360 dias. Após este período, foram avaliadas altura de planta em cm (AP), número de folhas verdes (NFV), número de folhas senescentes (NFS), número de microestacas (NM) e massa da planta seca em g (MPS). As variáveis que mais contribuíram para explicar a diferença existente no comportamento das plantas do limoeiro 'Rugoso da Flórida' no meio de cultura WPM foram NFV e AP com 61,63 e 35,08%, respectivamente. O meio de cultura WPM na sua concentração original com a adição de 25 g.L-1 de sacarose promoveu os melhores resultados na redução do crescimento das plantas in vitro do limoeiro 'Rugoso da Flórida', mantendo-as fisiologicamente sadias.

Androgênese: técnicas e suas principais aplicações / Androgenesis: technical and main applications

Os peixes oferecem vantagens técnicas em relação aos demais vertebrados por apresentarem um sistema biológico menos especializado, permitindo certas manipulações que são impraticáveis em outros. Algumas das facilidades são: fecundação externa, alta fecundidade e diferenciação sexual controlável. Desta forma o desenvolvimento de novas tecnologias com o domínio da técnica de androgênese possibilita sua aplicação na conservação de espécies ameaçadas de extinção, revitalização e no melhoramento genéticos de espécies de interesse econômico e ambiental. (AU)

Fish offer technical advantages compared to other vertebrates because they have a less specialized biological system, allowing certain manipulations that are impractical in others. Some facilities are: external fertilization, high fertility and controllable sexual differentiation. Thus the development of new technologies in the field of androgenesis technique enables its application in conservation of endangered species, revitalization and genetic improvement of species of economic and environmental interests. (AU)

Androgênese: técnicas e suas principais aplicações / Androgenesis: technical and main applications

Os peixes oferecem vantagens técnicas em relação aos demais vertebrados por apresentarem um sistema biológico menos especializado, permitindo certas manipulações que são impraticáveis em outros. Algumas das facilidades são: fecundação externa, alta fecundidade e diferenciação sexual controlável. Desta forma o desenvolvimento de novas tecnologias com o domínio da técnica de androgênese possibilita sua aplicação na conservação de espécies ameaçadas de extinção, revitalização e no melhoramento genéticos de espécies de interesse econômico e ambiental.

Fish offer technical advantages compared to other vertebrates because they have a less specialized biological system, allowing certain manipulations that are impractical in others. Some facilities are: external fertilization, high fertility and controllable sexual differentiation. Thus the development of new technologies in the field of androgenesis technique enables its application in conservation of endangered species, revitalization and genetic improvement of species of economic and environmental interests.

Ethylene synthesis inhibition effects on oxidative stress and in vitro conservation of Lippia filifolia (Verbenaceae) / Efeitos da inibição da síntese do etileno no estresse oxidativo e na conservação in vitro de Lippia filifolia (Verbenaceae)

This study aimed to investigate the effects of ethylene biosynthesis inhibitors on oxidative metabolisms and the in vitro conservation of Lippia filifolia, using the lipid peroxidation index (TBARS), antioxidative enzymes and pigments as biomarkers. We found that EDTA, sodium thiosulfate (STS) and especially Co had protective effects on oxidative stress in tissues cultured in vitro, resulting in a delay of the senescence and the reduction of subcultures frequency, con-tributing to the germplasm conservation of this species.(AU)

O objetivo deste estudo foi investigar os efeitos de inibidores da biossíntese do etileno no metabolismo oxidativo e na conservação in vitro de Lippia filifolia. Para isso, foram avaliados o índice de peroxidação lipídica (TBARS), a atividade de enzimas antioxidativas e o conteúdo de pigmentos fotossintéticos e de antocianinas. Os resultados evidenciaram que o EDTA, o tiossulfato de sódio (STS) e, especialmente, o Co apresentaram ação protetora sobre o estresse oxidativo nos tecidos, o que resultou em atraso no início da senescência das culturas e na redução da frequência dos subcultivos, contribuindo para a conservação do germoplasma dessa espécie.(AU)

Conservation of germplasm from wild animals of the caatinga biome

Background: The degradation of caatinga requires the development of strategies for its conservation and for the animals that inhabit in it. The need for studies on the conservation of germplasm from those animals led to the creation of the Center of Multiplication of Wild Animals of the Universidade Federal Rural do Semi-Árido (CEMAS/ UFERSA). This work presents data regarding the status of the conservation of the caatinga, and the main results related to the acquirement and conservation of germplasm from the animals that live in CEMAS. Review: The Caatinga biome is one of the most inhospitable landscapes of Brazil, and is considered the unique biome that is exclusively Brazilian due to a series of physical factors. This biome is the most altered by human action, with approximately 45.3% of the areas modified and only 1% protected by conservation units. Despite this, little attention has been given to its conservation and negligence is evident when investments in research on biodiversity and conservation of this biome are examined. The conservation of Caatinga biome is important for the maintenance of regional and global climate, the availability of drinking water, adequate soil for agriculture, and as an important part of the biodiversity of the planet. However, the caatinga remains as one of the lesser-known ecosystems in South America from a scientific point of view, which favors the process of its extinction. In order topreserve the wild species of the Brazilian northeast semi-arid, the Centre of Multiplication of Wild Animals ­ CEMAS/UFERSA not only promotes research, preservation, and conservation of wild species, but also develops technologies capable of producing animal protein, at low-cost for low-income familiar populations and meets producers interested in the creation of wild animals, using the criterion of sustainability. Nowadays, research projects aiming the obtaining of information regarding reproductive physiology and conservation of male and female germplasm from several species have been conducted. In collared peccaries (Tayassu tajacu), it was standardized that semen could be collected by electroejaculation under anesthesia using Propofol, followed by the cryopreservation in Tris supplemented by fructose or glucose and added by egg yolk and glycerol. In the female peccaries, studies on reproductive cycle and protocols for the conservation of ovarian preantral follicles are now being conducted. For the agouti (Dasyprocta aguti), a protocol for the obtaining and cryopreservation of epididymal sperm was established and now, we are trying to develop methodologies for their oocyte conservation. For the six-banded armadillos (Euphractus sexsinctus) and the coatis (Nasua nasua), several studies on semen technology, including protocols for collection and evaluation of sperm physiology, were conducted. Conclusions: In spite of our efforts to develop strategies for the conservation of animal germplasm, a genuine program of conservation for the Caatinga Biome will only be achieved when the knowledge and reproductive technologies be integrated into multidisciplinary programs for the preservation of the integrity of species ex situ and, preferably, in situ.