Desenvolvimento de estacas de alamanda amarela sob diferentes concentrações de ácido indolbutírico

The use of synthetic auxin as a stimulator of rooting in cuttings of Allamanda cathartica can provide increased of roots to development of marketable seedlings. The aim of this study was to evaluate the effect of three concentrations of indolbuthyric acid (IBA) on the development of callus tissue, rooting and sprouting in different stem cuttings from Allamanda cathartica. October 2008, cuttings were collected, immersed in fungicide Captan, treated with IBA and then planted in 45 days in randomized blocks. Every two weeks, we evaluated the percentage of occurrence of calluses, roots and shoots. Independent of IBA concentration, the woody and semi-woody showed the highest percentages of callus, root and sprout. It was found that, in the vegetative propagation of cuttings herbaceous, the application of IBA at 2000 ppm has great influence on development. For semi-woody, is not necessary for the application of IBA. The application of IBA at 250 ppm is sufficient to provide satisfactory development of callus tissue, rooting and shoots in cuttings woody, grown for a minimum period of 30 or 45 days.A utilização de auxina sintética como estimulador do enraizamento em estacas de alamanda pode propiciar aumento de raízes para a formação de mudas comercializáveis. Este trabalho objetivou avaliar o efeito de três concentrações do ácido indolbutírico (AIB) sobre o desenvolvimento de tecido caloso, enraizamento e brotação em estacas basais, medianas e subapicais de Allamanda cathartica. Em outubro de 2008, as estacas foram coletadas, imersas em fungicida Captan, tratadas com o AIB e estaqueadas por 45 dias em delineamento de blocos casualizados. Quinzenalmente, avaliou-se o percentual de ocorrência ou não de calos, raízes e brotação. Independente da concentração de AIB utilizada e da variável analisada, as estacas basais e medianas corresponderam aos maiores valores percentuais. Verificou-se que, para estacas subapicais, a aplicação de AIB a 2000 ppm exerce grande influência sobre seu desenvolvimento. Para as medianas não é necessária a aplicação de AIB. Já nas basais, a aplicação de AIB a 250 ppm é suficiente para proporcionar desenvolvimento satisfatório de tecido caloso, enraizamento e brotação, cultivadas por um período mínimo de 30 ou 45 dias. Development of yellow allamanda stem cuttings under differentindolebutyric acid concentrationsThe use of synthetic auxin as a stimulator of rooting in cuttings of Allamanda cathartica can provideincreased of roots to development of marketable seedlings. The aim of this study was to evaluatethe effect of three concentrations of indolbuthyric acid (IBA) on the development of callus tissue,rooting and sprouting in different stem cuttings from Allamanda cathartica. October 2008, cuttingswere collected, immersed in fungicide Captan, treated with IBA and then planted in 45 days inrandomized blocks. Every two weeks, we evaluated the percentage of occurrence of calluses, rootsand shoots. Independent of IBA concentration, the woody and semi-woody showed the highestpercentages of callus, root and sprout. It was found that, in the vegetative propagation of cuttingsherbaceous, the application of IBA at 2000 ppm has great influence on development. For semiwoody,is not necessary for the application of IBA. The application of IBA at 250 ppm is sufficient toprovide satisfactory development of callus tissue, rooting and shoots in cuttings woody, grown for aminimum period of 30 or 45 days