Micropropagation and medium-term conservation of Rosa pulverulenta

• Published in: Acta scientiarum. Agronomy 2011-04, Vol.33 (2), p.297-301
• Main Authors: Kavand, Somayeh, Kermani, Maryam Jafarkhani, Haghnazari, Ali, Khosravi, Pegah, Azimi, Mohamad Reza
• Format: Article
• Language: eng ; spa
• Subjects: AGRONOMY
• ISSN: 1679-9275; 1807-8621; 1807-8621
• DOI: 10.4025/actasciagron.v33i2.10279

In Iran, a large number of Rosa species have been exposed to extinction and therefore preservation techniques are necessary to safeguard their future. In the present investigation, the objectives were to optimize the micropropagation and medium-term conservation of one of these wild species, Rosa pulverulenta. At proliferation stage, the maximum number of new leaves (9.6) were produced on the medium containing 4 µM BAP + 0 µM [GA.sub.3], whereas the maximum number of axillary shoots (4.1) were observed in the medium containing 4 µM BAP + 3 µM [GA.sub.3]. The results for rooting experiments suggested that the highest increase in stem height (49.5 mm) at the acclimatization stage was observed in plantlets treated with 1 µM IBA + 0.5 µM NAA during the rooting stage. Comparing the refrigerator and phytotron conditions for medium-term conservation of in vitro plantlets indicated that although the refrigerator conditions resulted in lower growth rate compared with the phytotron, the survival rate in refrigerator (100%) was significantly higher than phytotron (87.5%). Furthermore, the growth rate of the plantlets from the refrigerator was accelerated during the recovery period and verged on to the ones stored in the phytotron. Keywords: in vitro conservation, micropropagation, proliferation, recovery, rooting, Rosa pulverulenta. Micropropagacao e conservacao durante medio prazo de Rosa pulverulenta. No Ira, um numero grande de especies de Rosa sao expostas a extincao. Por causa disto, as tecnicas de preservacao sao necessarias para garantir o futuro destas mesmas especies. Nesta investigacao, os objetivos foram aperfeicoar a micropropagacao e preservar durante medio prazo uma destas especies, Rosa pulverulenta. No estadio de proliferacao, o numero maximo de novas folhas (9,60) foi produzido no meio contendo 4 µM BAP + 0 µM [GA.sub.3], mas o numero maximo de gemas axilares foi observado no meio com 4 µM BAP + 3 µM [GA.sub.3]. Os resultados obtidos permitiram inferir que o maior aumento na altura de haste (49,5 mm) durante o estadio de climatizacao foi observado nos explantes tratados com 1 µM IBA + 0,5 µM NAA durante o enraizamento. Observa-se que embora a geladeira tenha proporcionado uma menor taxa de crescimento, a sobrevivencia em medio prazo foi maior (100,00%) do que no phytotron (87,50%). Alem disto, a taxa de crescimento dos explantes que foram mantidos na geladeira foi acelerada durante o periodo de recuperacao e ficaram proximas daquelas mantidas no phyt