Strigolactones are a class of phytohormones with various functions in plant development, stress responses, and in the interaction with (micro)organisms in the rhizosphere. While their effects on vegetative development are well studied, little is known about their role in reproduction. We investigated the effects of genetic and chemical modification of strigolactone levels on the timing and intensity of flowering in tomato (Solanum lycopersicum L.) and the molecular mechanisms underlying such effects. Results showed that strigolactone levels in the shoot, whether endogenous or exogenous, correlate inversely with the time of anthesis and directly with the number of flowers and the transcript levels of the florigen-encoding gene SINGLE FLOWER TRUSS (SFT) in the leaves. Transcript quantifications coupled with metabolite analyses demonstrated that strigolactones promote flowering in tomato by inducing the activation of the microRNA319-LANCEOLATE module in leaves. This, in turn, decreases gibberellin content and increases the transcription of SFT. Several other floral markers and morpho-anatomical features of developmental progression are induced in the apical meristems upon treatment with strigolactones, affecting floral transition and, more markedly, flower development. Thus, strigolactones promote meristem maturation and flower development via the induction of SFT both before and after floral transition, and their effects are blocked in plants expressing a miR319-resistant version of LANCEOLATE. Our study positions strigolactones in the context of the flowering regulation network in a model crop species.

• Keywords
• LANCEOLATE, flowering, miR319, strigolactones, tomato,
• MeSH
• Gibberellins metabolism   pharmacology   MeSH
• Flowers * drug effects   growth & development   metabolism   genetics   MeSH
• Lactones * metabolism   pharmacology   MeSH
• Plant Leaves metabolism   drug effects   MeSH
• MicroRNAs * genetics   metabolism   MeSH
• Gene Expression Regulation, Plant * drug effects   MeSH
• Plant Growth Regulators metabolism   pharmacology   MeSH
• Plant Proteins metabolism   genetics   MeSH
• Solanum lycopersicum * genetics   growth & development   metabolism   drug effects   MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Names of Substances
• Gibberellins MeSH
• Lactones * MeSH
• MicroRNAs * MeSH
• Plant Growth Regulators MeSH
• Plant Proteins MeSH

Salinity stress can significantly delay plant growth. It can disrupt water and nutrient uptake, reducing crop yields and poor plant health. The use of strigolactone can be an effective technique to overcome this issue. Strigolactone enhances plant growth by promoting root development and improvement in physiological attributes. The current pot study used strigolactone to amend chili under no salinity and salinity stress environments. There were four treatments, i.e., 0, 10µM strigolactone, 20µM strigolactone and 30µM strigolactone. All treatments were applied in four replications following a completely randomized design (CRD). Results showed that 20µM strigolactone caused a significant increase in chili plant height (21.07%), dry weight (33.60%), fruit length (19.24%), fruit girth (35.37%), and fruit yield (60.74%) compared to control under salinity stress. Significant enhancement in chili chlorophyll a (18.65%), chlorophyll b (43.52%), and total chlorophyll (25.09%) under salinity stress validated the effectiveness of 20µM strigolactone application as treatment over control. Furthermore, improvement in nitrogen, phosphorus, and potassium concentration in leaves confirmed the efficient functioning of 20µM strigolactone compared to other concentrations under salinity stress. The study concluded that 20µM strigolactone is recommended for mitigating salinity stress in chili plants. Growers are advised to apply 20µM strigolactone to enhance their chili production under salinity stress.

• Keywords
• Antioxidant, Chili chlorophyll content, Salinity stress, Strigolactone,
• MeSH
• Capsicum * MeSH
• Chlorophyll A MeSH
• Heterocyclic Compounds, 3-Ring * MeSH
• Camphor MeSH
• Lactones MeSH
• Menthol MeSH
• Salinity MeSH
• Salt Stress MeSH
• Publication type
• Journal Article MeSH
• Evaluation Study MeSH
• Names of Substances
• Chlorophyll A MeSH
• GR24 strigolactone MeSH Browser
• Heterocyclic Compounds, 3-Ring * MeSH
• Camphor MeSH
• Lactones MeSH
• Menthol MeSH

BACKGROUND: Drought is a major environmental stress that affects crop productivity worldwide. Although previous research demonstrated links between strigolactones (SLs) and drought, here we used barley (Hordeum vulgare) SL-insensitive mutant hvd14 (dwarf14) to scrutinize the SL-dependent mechanisms associated with water deficit response. RESULTS: We have employed a combination of transcriptomics, proteomics, phytohormonomics analyses, and physiological data to unravel differences between wild-type and hvd14 plants under drought. Our research revealed that drought sensitivity of hvd14 is related to weaker induction of abscisic acid-responsive genes/proteins, lower jasmonic acid content, higher reactive oxygen species content, and lower wax biosynthetic and deposition mechanisms than wild-type plants. In addition, we identified a set of transcription factors (TFs) that are exclusively drought-induced in the wild-type barley. CONCLUSIONS: Critically, we resolved a comprehensive series of interactions between the drought-induced barley transcriptome and proteome responses, allowing us to understand the profound effects of SLs in alleviating water-limiting conditions. Several new avenues have opened for developing barley more resilient to drought through the information provided. Moreover, our study contributes to a better understanding of the complex interplay between genes, proteins, and hormones in response to drought, and underscores the importance of a multidisciplinary approach to studying plant stress response mechanisms.

• Keywords
• Abscisic acid, Barley (Hordeum vulgare), Drought, Phytohormone, Proteome, Strigolactone, Transcriptome,
• MeSH
• Hordeum * genetics   MeSH
• Multiomics MeSH
• Droughts MeSH
• Perception MeSH
• Publication type
• Journal Article MeSH
• Names of Substances
• GR24 strigolactone MeSH Browser

Plant miRNAs are powerful regulators of gene expression at the post-transcriptional level, which was repeatedly proved in several model plant species. miRNAs are considered to be key regulators of many developmental, homeostatic, and immune processes in plants. However, our understanding of plant miRNAs is still limited, despite the fact that an increasing number of studies have appeared. This systematic review aims to summarize our current knowledge about miRNAs in spring barley (Hordeum vulgare), which is an important agronomical crop worldwide and serves as a common monocot model for studying abiotic stress responses as well. This can help us to understand the connection between plant miRNAs and (not only) abiotic stresses in general. In the end, some future perspectives and open questions are summarized.

• Keywords
• barley, environmental stress, gene expression, miRNAs, plants, regulation,
• MeSH
• Stress, Physiological genetics   MeSH
• Hordeum * genetics   metabolism   MeSH
• MicroRNAs * genetics   metabolism   MeSH
• Gene Expression Regulation, Plant MeSH
• Plants metabolism   MeSH
• Publication type
• Journal Article MeSH
• Systematic Review MeSH
• Names of Substances
• MicroRNAs * MeSH