Involvement of auxins in Impatiens walleriana plants grown in different plug tray systems during nursery

Abstract

The key role of auxins as integrators of environmental signals has become well-known in recent years, and emerging evidence indicates that auxin biosynthesis is an essential component of the overall mechanisms of plant tolerance to stress. However, although the knowledge of the involvement auxins in the responses related to the generation of roots and accumulation of biomass, studies in ornamental species concerning the commercial propagation in plug cell trays are scarce. Thus, the aim of this work was to evaluate the accumulation of pre-transplant biomass in Impatiens walleriana plants growing in two propagation systems (soilless medium-based plug cell trays and a floating system) with trays of different cell sizes and sprayed either with a single dose of the auxin indole acetic acid (IAA) or with two inhibitors of endogenous auxins, N-1-naphthylphthalamic acid (NPA) and 2,3,5-triiodobenzoic acid (TIBA). Our results demonstrate that plants from both floating system and those sprayed with IAA present both the highest leaf area and fresh and dry weight at the end of the experiment. Conversely, as a negative control, the use of NPA and TIBA as antagonists of the synthesis and translocation of auxins caused an opposite effect in such variables as compared to control plants. However, before making commercial recommendations, it would be necessary to evaluate the potential post-transplant effects of these treatments on the generation of I. walleriana yield.

Propagación de plantas de cannabis sativa (L.) mediante esquejes y uso de fitorreguladores auxínicos

“…Similarly, Sun et al (2023) observed the same pattern as the NAA and IBA concentration gradually increased within the range of 0~200~500~800 mg L -1 ; the rooting rate, average number of roots, maximum root length and rooting efficiency index initially increased followed by a decrease when applying a concentration of 1,000 mg L -1 . Salinas et al (2022) indicate that the spatial pattern of auxin accumulation at the tissue level may be due to a combination of localized auxin biosynthesis and nonpolar (in areas of high auxin concentration) and polar transport through cells.…”