The Use of Auxin Quantification for Understanding Clonal Tree Propagation

Abstract

Qualitative and quantitative hormone analyses have been essential for understanding the metabolic, physiological, and morphological processes that are influenced by plant hormones. Auxins are key hormones in the control of many aspects of plant growth and development and their endogenous levels are considered critical in the process of adventitious root induction. Exogenous auxins are used extensively in the clonal propagation of tree species by cuttings or tissue culture. Understanding of auxin effects has advanced with the development of increasingly accurate methods for auxin quantification. However, auxin analysis has been challenging because auxins typically occur at low concentrations, while compounds that interfere with their detection often occur at high concentrations, in plant tissues. Interference from other compounds has been addressed by extensive purification of plant extracts prior to auxin analysis, although this means that quantification methods have been limited by their expense. This review explores the extraction, purification, and quantification of auxins and the application of these techniques in developing improved methods for the clonal propagation of forestry trees.

Ficus enormis cuttings rooting: concentrations of indole butyric acid and seasonal variations

“…In fact, the correlation analysis between average temperatures of each season and rooting percentages showed a positive correlation close to 1.00, which has also been verified in other studies (Fragoso et al 2015). Similarly, the higher number of roots values and average length of the three largest roots per cutting demonstrate the high root vigor of the cuttings collected in these seasons, which may reflect on the stability, survival and development of seedlings in the field (Stuepp et al 2017).…”

VEGETATIVE RESCUE AND ROOTING OF CUTTINGS OF DIFFERENT STOCK PLANTS OF Sequoia sempervirens

“…Despite this, in the first collection, this stock plant presented the lowest survival rate and rooting. The differences observed are likely to occur because of hormonal changes occurred after the rescue process, due to stress caused to the tree , STUEPP et al, 2017, and also by genetic interactions with the environment, resulting in differences in rooting caused by the period of collection.…”

MINI-CUTTING TECHNIQUE FOR VEGETATIVE PROPAGATION OF Paratecoma peroba

“…Quantification of auxin is not a widely calculated in rooting studies owing to its low concentration in tissues and the interference of other compounds during the analysis. However, studies have shown a correlation between endogenous auxin levels and rooting capacity (Stuepp et al, 2017). It can be inferred that the linear reduction of R (%) owing to the concomitant increase of IBA concentrations might be linked to the degree of juvenility of the matrix plant, where the concentration of endogenous auxin (indol-3-acetic acid) of the shoots might be at sufficient levels to stimulate the emission of adventitious roots.…”