In vitro regeneration of Parapiptadenia rigida/Regeneracao in vitro de Parapiptadenia rigida

The aim of this research is to develop a micropropagation protocol for Parapiptadenia rigida using aseptic seedling explants from in vitro germinated seeds. To the sprout induction, cotyledonary and nodal segments were inoculated in a 1/2 WPM culture medium containing 0; 0.25; 0.50; 1.0mg [L.sup.-1] of BAP or KIN. The rooting of sprouted explants was rooted in a 1/4 WPM culture medium containing 0; 0.25; 1.0; 1.75mg [L.sup.-1] of IBA. It was not necessary the addition of cytokinin in medium to induce sprouting in cotyledonary and nodal segments. However, the doses of 0.50mg [L.sup.-1], independently of cytokinin type, promoted greater size of sprouts and the largest number of leaves per sprout. The highest rooting potential occurred in cotyledonary segments inoculated in medium with 1.0mg [L.sup.-1] of IBA. The use of this regeneration protocol allows obtaining Parapiptadenia rigida seedlings. Key words: red angico, rooting, micropropagation, plant growth regulator. O objetivo deste trabalho e estabelecer um protocolo de micropropagacao para a Parapiptadenia rigida utilizando explantes de plantulas assepticas obtidas da germinacao de sementes in vitro. Para a inducao de brotos, segmentos cotiledonares e nodais foram inoculados em meio de cultura 1/2 WPM acrescido de 0; 0,25; 0,50; 1,0mg [L.sup.-1] de BAP ou KIN. O enraizamento dos explantes com broto foi realizado em meio 1/4 WPM suplementado com 0; 0,25; 1,0; 1,75mg [L.sup.-1] de AIB. Nao foi necessaria a adicao de citocinina ao meio para inducao de brotos em segmento cotiledonar e nodal. Contudo, a dose de 0,50mg [L.sup.-1], independente do tipo de citocinina, promoveu maior tamanho dos brotos e maior numero de folhas por broto. O maior potencial de enraizamento ocorreu em segmentos cotiledonares inoculados em meio contendo 1,0mg [L.sup.-1] de AIB. A utilizacao desse protocolo de regeneracao permite a obtencao de mudas de Parapiptadenia rigida. Palavras-chave: angico-vermelho, enraizamento, micropropagacao, fitorregulador.