Regulation of growth of Lilium plantlets in liquid medium by application of paclobutrazol or ancymidol, for its amenability in a bioreactor system: growth parameters

Abstract

Effect of growth retardants (paclobutrazol or ancymidol) was studied in Lilium plantlets growing in liquid culture. A significant increase in leaf chlorophyll, epicuticular wax, plant dry weight and bulb starch contents were found in plantlets treated with growth retardants. A similar increase in the number of leaves, roots and bulbs was also noted. However, total leaf area and the fresh weight increased only marginally. These features resulted in robust plantlets that showed significantly improved ex vitro survival. Based on these features, a comprehensive index (CI) was calculated as a measure of quality of the plantlets, and it correlated well with their ex vitro survival. Treatment of plantlets with 3.4 microM paclobutrazol was found to be the best and its carry over effects were also minimal.

In vitro regeneration of Pinus brutia Ten. var. eldarica (Medw.) through organogenesis

“…The synergism between PAC and cytokinins has also been observed in potato tissue culture (Opatrná et al, 1997), sugarcane (Lorenzo et al, 1998), pineapple (Escalona et al, 1999), and lilium (Chen et al, 2005;Thakur et al, 2006). Organogenesis is an important regeneration pathway that facilitates the in vitro vegetative propagation of conifers (Tang et al, 1998).…”

Leucojum aestivum L. in vitro bulbs induction and acclimatization

“…It is known that growth retardants, such as paclobutrazol and ancymidol, inhibit gibberelin biosynthesis and stimulate bulb induction [16]. Ancymidol and paclobutrazol were found to be the best stimulators of Gladiolus cluster formation; they also enhance the formation of bulbs in Allium cepa, Lilium and Tulipa plants [16][17][18][19].…”

Controle da abscisão foliar e morfogênese in vitro em culturas de Anadenanthera colubrina (Vell.) Brenan var. cebil (Griseb) Altschul

“…O maior valor do comprimento da raiz foi observado no meio sem a adição do paclobutrazol e o menor, com 1,7 µM do mesmo composto, mostrando uma diferença de 185% em relação ao meio sem adição do paclobutrazol (Figura 2E). Observou-se comportamento quadrático das variáveis comprimento da raiz e número de raízes secundárias nas concentrações de paclobutrazol utilizadas, em que houve diferença altamente significativa na redução do número de raízes secundárias na presença de 6,8 µM de paclobutrazol, em comparação com o meio sem esse composto (Figura 2F (SMITH et al, 1990b;ROBERTS et al, 1992;SMITH et al, 1992) e em Lilium longiflorum (THAKUR et al, 2006). Esse aspecto de engrossamento das raízes pode ser benéfico na etapa de aclimatização, pois raízes mais vigorosas tendem a facilitar maior pegamento das mudas.…”