Hormonal endogenous changes in response to the exogenous 6-benzylaminopurine application in pre- and post-harvesting lilium flower stalks

Abstract

Phyto-hormones play a key role in regulating plant responses to stress. Cytokines are a type of phyto-hormones involved in the regulation of many important biological processes related to growth, development, and response to environmental variables. The exogenous application of cytokines increases the possibility of delaying senescence; however, this is a physiological process, and, under certain conditions, degradation processes may be triggered. The effect of 6-bencilaminopurine application and the endogenous hormonal changes involved in lilies floral stalks after their cutting were studied. In order to improve vase life and quality of Lilium longiflorum ‘Brindisi’ flower stalks, they were sprayed with 6-BAP, at a concentration of 300 ppm at pre-harvest, post-harvest, and pre- and post-harvest stages. After that, they were compared to non-sprayed control stalks. The application of 6-BAP caused endogenous hormonal changes in abscisic acid and cytokinin levels, and the most effective treatment was pre-harvest spraying. This treatment proved to be an appropriate method to improve the stalk tolerance to post-harvest stress as it delayed the appearance of senescence symptoms and reduced the speed of chlorophyll degradation with differences of up to 10% with respect to untreated stalks. In addition, the opening of flowers was delayed by up to 2 days, although there were no significant differences in total vase life.

In Vitro Propagation and Phytochemistry of Thymol-Producing Plants from a Horticultural Form of Thymus × josephi-angeli Mansanet & Aguil. (Lamiaceae)

“…For instance, Herrera-Isidron et al [47] recently proposed differential cytokinin perception depending on certain developmental events during the organogenesis in potatoes. In addition, it is still not clear whether cytokinin signaling takes place from one or more than one site at the cellular level (endoplasmic reticulum and/or plasma membrane), if the action is equal in all tissues or if it depends on the tissue, its developmental stage, and/or the action of signalling molecules from different origins [48], or if synergies exist between endogenous levels of hormones and exogenously applied PGRs [49]. Therefore, how exogenously applied BAP and 2iP (among other cytokinins) might act at the cellular or tissue level, and how this interaction is specifically translated into morphogenesis in vitro for different genotypes or plant species, cannot be stated.…”

Effects of water stress on the post-harvest quality of cut Lilium flowers

“…The restricted irrigation (RI) was performed with 8 emitters per linear bench meter, it started from the stem emergence and was applied at the same frequency than NI throughout the crop cycle. Fertilization started from stem emergence, approximately 20 days after planting, with a complete nutrient solution applied with irrigation water for both NI and RI (Mantilla et al, 2021). Only stalks with 5 flower buds were considered for the postharvest test.…”

“…On the other hand, previous studies have reported on the role of phytohormones in mitigating water stress in lilium plants, finding the exogenous application of 6-BAP as a tool to obtain stronger plants, with a longer vase life. That is why, in recent years, research has been carried out with the aim of increasing the biosynthesis of endogenous cytokinin (Luo, et al, 2021), improving the understanding of the mechanism that regulates senescence (Kanojia and Dijkwel, 2018) and intervene to delay this process during the post-harvest of cut flowers and other horticultural products (Gill et al, 2023, Mantilla et al, 2021.…”