The rose is one of the most important ornamental plants in the world. However, the cultivation systems used for roses often impose salt stress. Saline conditions occur naturally in some regions or by human activity in others with use of low quality water or excessive fertilizer application. In general, roses are considered sensitive to salinity. However, tolerance levels can be different among roses species and cultivars. Therefore, studies are needed that take into account characteristics of each species and how the exposure to salinity occurs. Management of water and nutrients can be important tools for mitigating the effects of high salt concentrations. Also, advances in biotechnology can be used for a better understanding of the physiological responses to salinity and to develop more salt tolerant rose cultivars. Thus, this paper aims to review the progress made and future prospects of salinity tolerance in commercial rose production. Keywords: salt stress, floriculture, water quality, nutrition RESUMO Salinidade na produção de rosas A rosa é uma das mais importantes plantas ornamentais do mundo. Os sistemas de cultivos utilizados para rosas muitas vezes impõem à cultura a condições de estresse salino. A salinidade pode ocorrer de forma natural ou antrópica, pelo uso de água de baixa qualidade ou excesso de fertilizantes. Em geral, as rosas são consideradas sensíveis a salinidade, no entanto, os níveis de tolerância diferem entre espécies e cultivares. Sendo assim são necessários estudos que considerem as características de cada espécie e a forma como ocorre essa exposição à salinidade. O manejo da água e nutrientes podem ser ferramentas importantes para mitigar os efeitos de concentrações de sal. Além disso, os avanços na área da biotecnologia podem ser utilizados para melhor entendimento das respostas fisiológicas e para desenvolver cultivares mais tolerantes de rosas. Diante disso, este artigo visa a revisar os avanços alcançados e perspectivas futuras na tolerância a salinidade na produção comercial de rosas. Palavras-chave: estresse salino, floricultura, qualidade da água, nutrição (1)

No abstract

Avocado is a fruit of high nutritional value rich in vitamins, proteins and minerals. However, its production is affected by post-harvest diseases, the main one being the anthracnose caused by fungi of the genus Colletotrichum. Thus, the objective of this study was to evaluate the effect of propolis on mycelial growth and on conidial germination of Colletotrichum spp. Five doses of propolis were tested: 0, 0.5, 1.0, 1.5 and 2.0 mL L -1 . To assay the assays, potato-dextrose agar (PDA) and Agar-Water (AW) were prepared, then the concentrations of propolis were incorporated therein. It was then poured into 9 cm diameter Petri dishes. After solidification, the mycelial disc plates (5 mm diameter) and 100 μL aliquot were transferred to the mycelial growth and conidial germination, respectively. The mycelial growth evaluations were transformed into mycelial growth rate index (MGRI). The increase of propolis concentrations of 0.5 to 2 mL L -1 reduced the MGRI and the percentage of conidia germination. The highest MGRI (10.05) and the highest percentage of germination (96%) were found in the concentration of 0 mL L -1 of própolis.

RESUMOSegmentos nodais de Genipa americana foram armazenados utilizando técnicas de encapsulamento e crescimento lento. Para o armazenamento de unidades encapsuláveis foram avaliados a influência da matriz de alginato de sódio a 3% e 4%, o efeito de um pré-tratamento com soluções de sacarose a 0, 0,25 e 0,50 M, bem como o efeito da temperatura de 8ºC e 15ºC durante 30 dias de armazenamento, sendo avaliada a porcentagem de ruptura dessas cápsulas após 50 dias de inoculação. Para o crescimento lento foram avaliadas diferentes concentrações de sacarose (30, 45 e 60 g L -1 ) e temperatura 8ºC e 15ºC após 90 e 180 dias de armazenamento. Sendo avaliada a porcentagem de sobrevivência e regeneração, comprimento da parte área, número de brotos e folhas. Apenas as unidades encapsuláveis armazenadas à 15ºC sobreviveram. Nesta temperatura, a ruptura da cápsula foi melhor no pré-tratamento com 0 M de sacarose. Para o crescimento lento, a temperatura de 8º também não permitiu sobrevivência dos explantes. Assim, após 180 dias os melhores resultados ocorreram na temperatura de 15°C com acréscimo de 60 g L -1 de sacarose ao meio de cultura. Dessa forma, pode-se concluir que é possível fazer o armazenamento da espécie utilizando essas técnicas. Palavras-chave:Jenipapo. Conservação in vitro. Unidades encapsuláveis. Temperatura. Cerrado. CONSERVATION OF Genipa americana: ENCAPSULATION AND SLOW GROWTH TECHNIQUES __________________________________________ RESUMONodal segments of Genipa americana were stored using encapsulation and slow growth techniques. The influence of the 3% and 4% sodium alginate matrix, the effect of a pretreatment with 0, 0,25 and 0,50 M sucrose solutions, as well the effect of 8ºC and 15ºC temperature during storege for 30 days. It was evaluated the percentage of rupture of these capsules after 50 days of inoculation. For the slow growth, different sucrose concentrations (30, 45 and 60 g L -1 ) and temperature 8ºC and 15ºC after storege for 90 and 180 days were evaluated. It was evaluated the percentage of survival and regeneration, shoot lenght, shoots and leaves number. Only the encapsulating units stored at 15 °C survived. At this temperature, the capsule rupture was better in pretreatment with 0 M sucrose. For the slow growth, the temperature of 8ºC also did not allow the survival of the explants. Thus, after 180 days the best results occurred at the temperature of 15 °C with the addition of 60 g L -1 of sucrose to the culture medium. In this way, it can be concluded that it is possible to make the storage of the species using these techniques. Palavras-chave:Jenipapo. In vitro conservation. Encapsulating units. Temperature. Cerrado.

Tropical species may require higher temperatures as well as higher growth regulator concentrations for in vitro development. Since these conditions may affect plant metabolism, the objective of this study was to identify how different temperatures and gibberellin concentrations may affect the in vitro development of strelitzia embryos, analyzing the effect on ROS and cytogenetic stability. Zygotic embryos were cultivated on MS medium supplemented with 5, 10 and 20 µM GA3 under temperatures of 25 °C, 30/25 °C and 30 °C. After 60 days, higher embryonic germination rate (72%) and shoot length of plantlets (3.14 cm) were observed on medium containing 20 µM gibberellic acid (GA3). At this concentration, there was an increase in nitrate reductase activity with no change in the cytogenetic stability. The temperature influenced only shoot and root lengths, which were highest at 25 °C. At 30 °C, superoxide dismutase (SOD) and ascorbate peroxidase (APX) activities increased compared with those at 25 °C. Thus, the addition of 20 µM GA3 to the culture medium and a temperature of 25 °C in the growth room should be used for zygotic embryo culture of strelitzia.