Manipulation of Barley Development and Flowering Time by Exogenous Application of Plant Growth Regulators

Abstract

Matching flowering time to the optimal flowering period in Mediterranean cropping zones is pivotal to maximize yield. Aside from variety selection and sowing date, growers have limited options to alter development in season. Plant hormones and growth regulators are used in perennial horticultural systems to manipulate development and floral initiation. In this study, a range of plant hormonal products were tested to analyze their effects on barley (Hordeum vulgare L) development by exogenous spray applications. Plants were grown in controlled conditions under long and short photoperiods with different vernalization treatments. The gibberellin (GA) products demonstrated the greatest potential for altering development. The GA inhibitor trinexapac-ethyl was able to delay the time to flowering in genetically divergent barley cultivars by up to 200 degree days under controlled conditions. A similar delay in flowering could be achieved via application at both early (GS13) and late (GS33) stages, with higher rates delaying flowering further. Notably, trinexapac-ethyl was able to extend the duration of pre-anthesis phases of development. By contrast, GA3 was unable to accelerate development under extreme short (8 h) or long (16 h) day lengths. There was also little evidence that GA3 could reproducibly accelerate development under intermediate 10–12 h day lengths. In addition, sprays of the cytokinin 6-benzyladenine (6-BA) were unable to reduce the vernalization requirement of the winter genotype Urambie. The present study provides baseline data for plant growth regulator treatments that delay cereal development. These treatments might be extended in field studies to align flowering of early sown crops to the optimal flowering period.

Application of Data Modeling, Instrument Engineering and Nanomaterials in Selected Medid the Scientific Recinal Plant Tissue Culture

“…Plant development can be manipulated by adding PGRs at specific stages of growth or maturation by adding plant hormones such as IAA, naphthaleneacetic acid (NAA), 6-furfurylaminopurine (KT), 6-benzylaminopurine (6-BA), ethylene, abscisic acid (ABA), brassinolide (BL), jasmonic acid (JA), salicylic acid (SA), etc. [ 42 ]. All of these can stimulate further developmental responses.…”

Heat stress responses vary during floret development in European spring barley cultivars

“…Reproductive organs are significantly more vulnerable to high temperatures than other plant organs. Planting of crops is typically timed to minimise high temperature exposure during the later reproductive stages, however the fluctuations and extremes of temperature that are now occurring mean that there is an increasing probability that peaks of high temperature will overlap with the flowering period (Teixeira et al, 2013;Kupke et al, 2022). It is proposed that "stay green" traits that enable photosynthesis to be maintained for longer, particularly under environmental stress, may enable yield losses due to abiotic stress to be minimized (Barnabas et al, 2008).…”

Jasmonates, gibberellins, and powdery mildew modify cell cycle progression and evoke differential spatiotemporal responses along the barley leaf

“…Barley is a widely grown cereal that is cultivated for animal feed, malting, and human consumption ( Akar et al ., 2004 ). In plants, growth, development, and stress responses are modulated by different levels and gradients of phytohormones ( Kupke et al , 2022 ; Cao et al , 2017 ). Numerous studies have shown how such hormones affect the signalling networks that modulate cell division and thus modulate growth and development, including abscisic acid (ABA; Świątek et al , 2002 ; ( Skirycz and Inzé, 2010 ), auxin ( Perrot-Rechenmann, 2010 ), brassinosteroids (reviewed by Clouse, 2011 ), cytokinins (reviewed by Haberer and Kieber, 2002 ), gibberellins (GAs; Achard et al ., 2009 ), and jasmonates (JAs, including active precursors and derivatives of jasmonic acid; Noir et al , 2013 ; Bömer et al, 2018 ).…”