Auxin–cytokinin and auxin–gibberellin interactions during morphogenesis of the compound leaves of pea (Pisum sativum)

Abstract

A number of mutations that alter the form of the compound leaf in pea (Pisum sativum) has proven useful in elucidating the role that auxin might play in pea leaf development. The goals of this study were to determine if auxin application can rescue any of the pea leaf mutants and if gibberellic acid (GA) plays a role in leaf morphogenesis in pea. A tissue culture system was used to determine the effects of various auxins, GA or a GA biosynethesis inhibitor (paclobutrazol) on leaf development. The GA mutant, nana1 (na1) was analyzed. The uni-tac mutant was rescued by auxin and GA and rescue involved both a conversion of the terminal leaflet into a tendril and an addition of a pair of lateral tendrils. This rescue required the presence of cytokinin. The auxins tested varied in their effectiveness, although methyl-IAA worked best. The terminal tendrils of wildtype plantlets grown on paclobutrazol were converted into leaflets, stubs or were aborted. The number of lateral pinna pairs produced was reduced and leaf initiation was impaired. These abnormalities resembled those caused by auxin transport inhibitors and phenocopy the uni mutants. The na1 mutant shared some morphological features with the uni mutants; including, flowering late and producing leaves with fewer lateral pinna pairs. These results show that both auxin and GA play similar and significant roles in pea leaf development. Pea leaf morphogenesis might involve auxin regulation of GA biosynthesis and GA regulation of Uni expression.

Germinação in vitro de variedades de rosa-do-deserto

“…The GA 3 acts mainly elongating axillary organs such as stems, flowers and inflorescences, and in the development of trichomes and seeds. This elongation probably occurs due to the increase of soluble carbohydrates, product of GA 3 metabolic activity (DeMASON, 2005;BIALECKA and KEPCZNSKI, 2007).…”

Plant growth regulators optimization for in vitro cultivation of the orchid Guarianthe skinneri (Bateman) Dressier & W.E.Higgins

“…The overall mean shoot length was 1.0 cm and increased with 0.5 cm when grown in MS medium supplemented with 4.6 x 10 -9 μM GA 3 , 0.0043 μM BA, 1.2 x 10 -5 μM NAA and 14.92 μM IAA (Table III). The model derived from the experimental data explained 82% of the variability (Table IV). GA 3 is best known for its role in elongation of axial organs, such as stems, petioles and inflorescences (DeMason 2005). The effects of GA 3 on shoot elongation are well documented for several plants cultivated in vitro, e.g.…”

In vitro propagation and chemical profiling of <i>Herminium lanceum</i> (Thunb. ex Sw.) Vuijk, a medicinally important orchid, for therapeutically important phenolic acids

“…Therefore, these were transferred to BM fortified with either activated charcoal (0.1% AC), polyvinylpyrrolidone (0.1% PVP), different concentrations of gibberellic acid (GA 3 ) or the last in combination with either AC or PVP (Table 3). GA 3 is well-known for its effect on elongation of stems, petioles and inflorescences (DeMason 2005). It promoted the elongation of shoots significantly at all the tested concentrations (Table 3, Figure 1J).…”