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In plants, vegetative growth is controlled by synergistic and/or antagonistic effects of many regulatory factors. Here, the authors demonstrate that the ubiquitin ligase seven in absentia1 (SINA1) mammalian BTF2‐like transcription factors, Drosophila synapse‐associated proteins, and yeast DOS2‐like proteins (BSD1) function as a regulatory module to control vegetative growth in tomato via regulation of the production of plant growth hormone gibberellin (GA). SINA1 negatively regulates the protein level of BSD1 through ubiquitin‐proteasome‐mediated degradation, and the transgenic tomato over‐expressing SINA1 (SINA1‐OX) resembles the dwarfism phenotype of the BSD1‐knockout (BSD1‐KO) tomato plant. BSD1 directly activates expression of the BSD1‐regulated gene 1 (BRG1) via binding to a novel core BBS (standing for BSD1 binding site) binding motif in the BRG1 promoter. Knockout of BRG1 (BRG1‐KO) in tomato also results in a dwarfism phenotype, suggesting BRG1 plays a positive role in vegetative growth as BSD1 does. Significantly, GA contents are attenuated in transgenic SINA1‐OX, BSD1‐KO, and BRG1‐KO plants exhibiting dwarfism phenotype and exogenous application of bioactive GA3 restores their vegetative growth. Moreover, BRG1 is required for the expression of multiple GA biosynthesis genes and BSD1 activates three GA biosynthesis genes promoting GA production. Thus, this study suggests that the SINA1‐BSD1 module controls vegetative growth via direct and indirect regulation of GA biosynthesis in tomato. [ABSTRACT FROM AUTHOR]

ABSTRACT Phytochrome Interacting Factor 4 (PIF4) plays a central role in coordinating plant growth regulation by integrating multiple environmental cues. However, studies on whether and how PIF4 regulates plant immunity have inconsistent findings. In this study, we investigated the role of PIF4 in disease resistance against Pst DC3000 by characterizing its loss‐of‐function mutants using different inoculation strategies. Our findings reveal that pif4 mutants exhibit enhanced disease resistance with spray inoculation but not with infiltration inoculation compared to wild‐type plants, and that mutants displayed more closed stomata apertures, indicating that PIF4 promotes stomatal opening. Importantly, expression of PIF4 by a guard‐cell‐specific promoter was sufficient to restore disease resistance to the wild‐type level in the pif4 mutant. Additionally, PIF4 overexpression enhances disease symptom development independent of disease resistance and chlorophyll degradation, while the loss of PIF4 function leads to higher chlorophyll accumulation. Thus, our findings highlight a crucial function of PIF4 in regulating stomata‐mediated disease resistance and chlorophyll accumulation, providing new insights into the connection of growth and defense in plants. [ABSTRACT FROM AUTHOR]

Nitric oxide (NO) and other reactive nitrogen species (RNS) are considered to be signaling molecules in higher plants involved in the regulation of growth and development processes. However, the molecular mechanisms of their formation, removal, and participation in plant responses to adverse environmental stimuli remain largely unclear. Therefore, the aim of this study was to assess the influence of selected single stresses and combined stresses (i.e., Rhopalosiphum padi L. aphid infestation, drought, aphid infestation, and drought) and post-stress recovery on the contents of NO and peroxynitrite anion (ONOO−), as well as the levels of mRNA and protein nitration (i.e., the 8-nitroguanine and protein 3-nitrotyrosine amounts, respectively), in maize seedlings (Zea mays L.). Moreover, the expression patterns of the two tested genes (nos-ip, encoding nitric oxide synthase-interacting protein, and nr1, encoding nitrate reductase 1) involved in NO metabolism in maize plants were quantified. We identified significant intervarietal, time-course, and stress-dependent differences in the levels of the quantified parameters. Under the investigated stress conditions, the aphid-resistant Waza cv. seedlings were characterized by a higher and earlier NO accumulation and mRNA nitration level and an increased expression of the two target genes (nos-ip and nr1), compared to the aphid-susceptible Złota Karłowa cv. seedlings. Conversely, the Złota Karłowa plants responded with a greater elevation in the content of ONOO− and protein 3-nitrotyrosine than the Waza cv. plants The multifaceted role of NO and its derivatives in maize plants challenged by single and combined stresses, as well as during post-stress recovery, is discussed. [ABSTRACT FROM AUTHOR]

Phytohormones are signaling substances that control essential elements of growth, development, and reactions to environmental stress. Drought, salt, heat, cold, and floods are a few examples of abiotic factors that have a significant impact on plant development and survival. Complex sensing, signaling, and stress response systems are needed for adaptation and tolerance to such pressures. Abscisic acid (ABA) is a key phytohormone that regulates stress responses. It interacts with the jasmonic acid (JA) and salicylic acid (SA) signaling pathways to direct resources toward reducing the impacts of abiotic stressors rather than fighting against pathogens. Under exposure to nanoparticles, the plant growth hormones also function as molecules that regulate stress and are known to be involved in a variety of signaling cascades. Reactive oxygen species (ROS) are detected in excess while under stress, and nanoparticles can control their formation. Understanding the way these many signaling pathways interact in plants will tremendously help breeders create food crops that can survive in deteriorating environmental circumstances brought on by climate change and that can sustain or even improve crop production. Recent studies have demonstrated that phytohormones, such as the traditional auxins, cytokinins, ethylene, and gibberellins, as well as more recent members like brassinosteroids, jasmonates, and strigolactones, may prove to be significant metabolic engineering targets for creating crop plants that are resistant to abiotic stress. In this review, we address recent developments in current understanding regarding the way various plant hormones regulate plant responses to abiotic stress and highlight instances of hormonal communication between plants during abiotic stress signaling. We also discuss new insights into plant gene and growth regulation mechanisms during stress, phytohormone engineering, nanotechnological crosstalk of phytohormones, and Plant Growth-Promoting Rhizobacteria's Regulatory Powers (PGPR) via the involvement of phytohormones. [ABSTRACT FROM AUTHOR]

Although graphene oxide (GO) has extensive recognized application prospects in slow-release fertilizer, plant pest control, and plant growth regulation, the incorporation of GO into nano herbicides is still in its early stages of development. This study selected a pair of sweet corn sister lines, nicosulfuron (NIF)-resistant HK301 and NIF-sensitive HK320, and sprayed them both with 80 mg kg–1 of GO-NIF, with clean water as a control, to study the effect of GO-NIF on sweet corn seedling growth, photosynthesis, chlorophyll fluorescence, and antioxidant system enzyme activity. Compared to spraying water and GO alone, spraying GO-NIF was able to effectively reduce the toxic effect of NIF on sweet corn seedlings. Compared with NIF treatment, 10 days after of spraying GO-NIF, the net photosynthetic rate (A), stomatal conductance (Gs), transpiration rate (E), photosystem II photochemical maximum quantum yield (Fv/Fm), photochemical quenching coefficient (qP), and photosynthetic electron transfer rate (ETR) of GO-NIF treatment were significantly increased by 328.31%, 132.44%, 574.39%, 73.53%, 152.41%, and 140.72%, respectively, compared to HK320. Compared to the imbalance of redox reactions continuously induced by NIF in HK320, GO-NIF effectively alleviated the observed oxidative pressure. Furthermore, compared to NIF treatment alone, GO-NIF treatment effectively increased the activities of superoxide dismutase (SOD), guaiacol peroxidase (POD), catalase (CAT), and ascorbate peroxidase (APX) in both lines, indicating GO induced resistance to the damage caused by NIF to sweet corn seedlings. This study will provides an empirical basis for understanding the detoxification promoting effect of GO in NIF and analyzing the mechanism of GO induced allogeneic detoxification in cells. [ABSTRACT FROM AUTHOR]

Peanut is a significant source of protein for human consumption. One of the primary objectives in peanut breeding is the development of new cultivars with enhanced nutritional values. To further this goal, a genome‐wide association study (GWAS) was conducted to analyze seed amino acids contents in 390 diverse peanut accessions collected worldwide, mainly from China, India, and the United States, in 2017 and 2018. These accessions were assessed for their content of 10 different amino acids. Variations in amino acids contents were observed, and arginine (Arg) was found to have the highest average value among all the amino acids quantified. The geographical distribution of the accessions also revealed variations in amino acids contents. High and positive correlation coefficients were observed among the amino acids, suggesting linked metabolic pathways or genetic regulation. A total of 88 single nucleotide polymorphisms (SNPs) spanning various chromosomes were identified, each associated with different amino acids. By using a combination of GWAS, expression anlaysis, and genomic polymorphisim comparisions, the Ahy_A09g041582 (LAC15) gene located on chromrosome A09 was identified as the key candidate which might be involved in plant growth and regulation and may alter amino acids levels. Expression analysis indicated that Ahy_A09g041582 has higher expressions in the shells and seeds than other genes located in the candidate region. This study may help with marker‐based breeding of peanuts with higher nutritional value and offers fresh insights into the genetic basis of the amino acids contents of peanuts. [ABSTRACT FROM AUTHOR]

This special issue of the Journal of Plant Growth Regulation focuses on the role of plant specialized metabolites in various aspects of plant growth, adaptability, and productivity. The articles cover a wide range of topics, including the interaction between native rhizobacteria and plants, the pathogenic interaction between ginger and Fusarium wilt, and the use of bacterial endophytes to promote plant growth. Other articles discuss the mitigation of salt stress in carnation plants, the increase of carbazole alkaloids in Murraya koenigii leaves, and the accumulation of steviol glycosides in Stevia rebaudiana plants. The document also explores the relationship between specialized metabolites and plant phytohormones, and how they impact plant growth and stress tolerance. The articles provide valuable insights into plant biosynthetic pathways and offer potential applications for optimizing plant growth and yield in sustainable contexts. [Extracted from the article]

Salt stress has a detrimental impact on both plant growth and global crop yields. B‐box proteins have emerged as pivotal players in plant growth and development regulation. Although the precise role of B‐box proteins orchestrating salt stress responses in B. napus (Brassica napus) is not well understood in the current literature, further research and molecular explorations are required. Here, we isolated the B‐box protein BnBBX22.A07 from B. napus. The overexpression of BnBBX22.A07 significantly improved the salt tolerance of Arabidopsis (Arabidopsis thaliana) and B. napus. Transcriptomic and histological analysis showed that BnBBX22.A07 enhanced the salt tolerance of B. napus by activating the expression of reactive oxygen species (ROS) scavenging‐related genes and decreasing salt‐induced superoxide anions and hydrogen peroxide. Moreover, BnBBX22.A07 interacted with BnHY5.C09, which specifically bound to and activated the promoter of BnWRKY33.C03. The presence of BnBBX22.A07 enhanced the activation of BnHY5.C09 on BnWRKY33.C03. Overexpression of BnHY5.C09 and BnWRKY33.C03 improved the salt tolerance of Arabidopsis. Functional analyses revealed that BnBBX22.A07‐mediated salt tolerance was partly dependent on WRKY33. Taken together, we demonstrate that BnBBX22.A07 functions positively in salt responses not only by activating ROS scavenging‐related genes but also by indirectly activating BnWRKY33.C03. Notably, our study offers a promising avenue for the identification of candidate genes that could be harnessed in breeding endeavours to develop salt‐resistant transgenic crops. Summary statement: BnBBX22.A07 functions positively in salt responses not only by activating ROS scavenging‐related genes, but also by indirectly activating BnWRKY33.C03 in Brassica napus. [ABSTRACT FROM AUTHOR]

Zinc (Zn) deficiency is a serious problem for agriculture and human health. Under Zn deficient conditions, many physiological functions in plants are disturbed, and cellular homeostasis is badly affected. Under these circumstances, wheat crops produce fewer yields having low concentration of micronutrients in grains. In this modern era of nanotechnology, a possible way to achieve maximum plant growth in a sustainable manner is using nanoparticles (NPs). The present study was developed to observe the ameliorating effect of Zn nanoparticles (ZnNPs) as priming agents in wheat (Triticum aestivum L.) plants grown under saline circumstances. Five levels of ZnNPs: 0, 25, 50, 75, and 100 ppm, and two levels of salinity: 2 and 12 dS m−1, were studied. The mitigation of stress was seen in ZnNPs-applied wheat plants under salt stress, with a marked rise in total soluble sugars and total free amino acids. A significant decrease in pigment contents, total soluble proteins, and gas exchange characteristics was observed in the stress condition. Application of ZnNPs significantly improved the working of antioxidant enzymes, increased biochemical attributes, and helped regulate water relations and lipid peroxidation in wheat plants in a dose-dependent manner. It is worth mentioning that the application of ZnNPs at a rate of 100 ppm as a seed priming agent was observed to be the most distinct treatment in the accumulation of osmolytes and regulation of growth in wheat plants. [ABSTRACT FROM AUTHOR]

Background: The yield of major crops is generally limited by sink capacity and source strength. Cucumber is a typical raffinose family oligosaccharides (RFOs)–transporting crop. Non-coding RNAs and alternative polyadenylation (APA) play important roles in the regulation of growth process in plants. However, their roles on the sink‒source regulation have not been demonstrated in RFOs–translocating species. Results: Here, whole–transcriptome sequencing was applied to compare the leaves of cucumber under different sink strength, that is, no fruit-carrying leaves (NFNLs) and fruit-carrying leaves (FNLs) at 12th node from the bottom. The results show that 1101 differentially expressed (DE) mRNAs, 79 DE long non–coding RNAs (lncRNAs) and 23 DE miRNAs were identified, which were enriched in photosynthesis, energy production and conversion, plant hormone signal transduction, starch and carbohydrate metabolism and protein synthesis pathways. Potential co–expression networks like, DE lncRNAs–DE mRNAs/ DE miRNAs–DE mRNAs, and competing endogenous RNA (ceRNA) regulation models (DE lncRNAs–DE miRNAs–DE mRNAs) associated with sink‒source allocation, were constructed. Furthermore, 37 and 48 DE genes, which enriched in MAPK signaling and plant hormone signal transduction pathway, exist differentially APA, and SPS (CsaV3_2G033300), GBSS1 (CsaV3_5G001560), ERS1 (CsaV3_7G029600), PNO1 (CsaV3_3G003950) and Myb (CsaV3_3G022290) may be regulated by both ncRNAs and APA between FNLs and NFNLs, speculating that ncRNAs and APA are involved in the regulation of gene expression of cucumber sink‒source carbon partitioning. Conclusions: These results reveal a comprehensive network among mRNAs, ncRNAs, and APA in cucumber sink–source relationships. Our findings also provide valuable information for further research on the molecular mechanism of ncRNA and APA to enhance cucumber yield. [ABSTRACT FROM AUTHOR]

A comprehensively analysis of the transcriptomics and metabolomics was conducted to investigate the mechanism of plant growth regulators on the quality of jujube fruit. After the application of plant growth regulators, a total of 3097 differentially expressed genes (DEGs) were identified, which were mainly annotated in 123 pathways such as flavonoid biosynthesis, metabolism of alanine, aspartate, and glutamate. In addition, 1091 differential expressed metabolites (DEMs), including 519 up-regulated and 572 down-regulated metabolites, were significantly altered after application of plant growth regulators. DEGs and DEMs simultaneously annotated 69 metabolic pathways, including biosynthesis of phenylpropane, flavonoid, starch and sucrose. The key genes in flavonoid biosynthesis pathway were revealed, which may play an important role in plant growth regulator regulation quality of jujube fruit. Besides, the application of plant growth regulator during the jujube flowering period increased the contents of gibberellin and indole-3-acetic acid in leaves, and decreased the contents of abscisic acid. The results may help to reveal the metabolic network and molecular mechanism of plant growth regulators in jujube fruit. [ABSTRACT FROM AUTHOR]

The cytokinin response factors (CRFs) are pivotal players in regulating plant growth, development, and responses to diverse stresses. Despite their significance, comprehensive information on CRF genes in the primary food crop, maize, remains scarce. In this study, a genome-wide analysis of CRF genes in maize was conducted, resulting in the identification of 12 members. Subsequently, we assessed the chromosomal locations, gene duplication events, evolutionary relationships, conserved motifs, and gene structures of all ZmCRF members. Analysis of ZmCRF promoter regions indicated the presence of cis-regulatory elements associated with plant growth regulation, hormone response, and various abiotic stress responses. The expression patterns of maize CRF genes, presented in heatmaps, exhibited distinctive patterns of tissue specificity and responsiveness to multiple abiotic stresses. qRT-PCR experiments were conducted on six selected genes and confirmed the involvement of ZmCRF genes in the plant's adaptive responses to diverse environmental challenges. In addition, ZmCRF9 was demonstrated to positively regulate cold and salt tolerance. Ultimately, we explored the putative interaction partners of ZmCRF proteins. In summary, this systematic overview and deep investigation of ZmCRF9 provides a solid foundation for further exploration into how these genes contribute to the complex interplay of plant growth, development, and responses to stress. [ABSTRACT FROM AUTHOR]

Copyright of Science & Technology of Food Industry is the property of Science & Technology of Food Industry Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Plants are sessile organisms that are often subjected to a multitude of environmental stresses, with the occurrence of these events being further intensified by global climate change. Crop species therefore require specific adaptations to tolerate climatic variability for sustainable food production. Plant stress results in excess accumulation of reactive oxygen species leading to oxidative stress and loss of cellular redox balance in the plant cells. Moreover, enhancement of cellular oxidation as well as oxidative signals has been recently recognized as crucial players in plant growth regulation under stress conditions. Multiple roles of redox regulation in crop production have been well documented, and major emphasis has focused on key redox-regulated proteins and non-protein molecules, such as NAD(P)H, glutathione, peroxiredoxins, glutaredoxins, ascorbate, thioredoxins and reduced ferredoxin. These have been widely implicated in the regulation of (epi)genetic factors modulating growth and health of crop plants, with an agricultural context. In this regard, priming with the employment of chemical and biological agents has emerged as a fascinating approach to improve plant tolerance against various abiotic and biotic stressors. Priming in plants is a physiological process, where prior exposure to specific stressors induces a state of heightened alertness, enabling a more rapid and effective defense response upon subsequent encounters with similar challenges. Priming is reported to play a crucial role in the modulation of cellular redox homeostasis, maximizing crop productivity under stress conditions and thus achieving yield security. By taking this into consideration, the present review is an up-to-date critical evaluation of promising plant priming technologies and their role in the regulation of redox components toward enhanced plant adaptations to extreme unfavorable environmental conditions. The challenges and opportunities of plant priming are discussed, with an aim of encouraging future research in this field toward effective application of priming in stress management in crops including horticultural species. [ABSTRACT FROM AUTHOR]

Selenium nanoparticles (SeNPs) exhibit great potential across a spectrum of applications, yet the development of effective methods for their large-scale preparation remains an emerging field. Herein, we propose an effective method to produce SeNPs using nontoxic bulk selenium powder. By dissolving selenium powder in ethylenediamine (EDA) to create a homogeneous Se–EDA solution, SeNPs can be easily formed by adding this solution to water. The obtained SeNPs exhibit small and uniform size, fine water dispersibility, low cytotoxicity, and also exceptional antioxidant activities. Furthermore, we conducted a comprehensive examination of the potential for using SeNPs in the cultivation of selenium-enriched bean sprouts. Our findings indicate that SeNPs exert a minimal effect on the growth of bean sprouts while substantially boosting the levels of seleno-amino acids within them. At a SeNP concentration of 20 mg/L, the concentration of seleno-amino acids in the bean sprouts can increase to as much as 0.182 μg/g. This study not only provides a viable approach for producing SeNPs, but also opens up an opportunity for the cultivation of selenium-rich foods that meet the requirements of human health. [ABSTRACT FROM AUTHOR]

Bacillus genera, especially among rhizobacteria, are known for their ability to promote plant growth and their effectiveness in alleviating several stress conditions. This study aimed to utilize indigenous Bacillus cereus PM38 to degrade four organophosphate pesticides (OPs) such as chlorpyrifos (CP), profenofos (PF), monocrotophos (MCP), and dimethoate (DMT) to mitigate the adverse effects of these pesticides on cotton crop growth. Strain PM38 exhibited distinct characteristics that set it apart from other Bacillus species. These include the production of extracellular enzymes, hydrogen cyanide, exopolysaccharides, Indol-3-acetic acid (166.8 μg/mL), siderophores (47.3 μg/mL), 1-aminocyclopropane-1-carboxylate deaminase activity (32.4 μg/mL), and phosphorus solubilization (162.9 μg/mL), all observed at higher concentrations. This strain has also shown tolerance to salinity (1200 mM), drought (20% PEG-6000), and copper and cadmium (1200 mg/L). The amplification of multi-stress-responsive genes, such as acdS, ituC, czcD, nifH, sfp, and pqqE, further confirmed the plant growth regulation and abiotic stress tolerance capability in strain PM38. Following the high-performance liquid chromatography (HPLC) analysis, the results showed striking compatibility with the first kinetic model. Strain PM38 efficiently degraded CP (98.4%), PF (99.7%), MCP (100%), and DMT (95.5%) at a concentration of 300 ppm over 48 h at 35 °C under optimum pH conditions, showing high coefficients of determination (R2) of 0.974, 0.967, 0.992, and 0.972, respectively. The Fourier transform infrared spectroscopy (FTIR) analysis and the presence of opd, mpd, and opdA genes in the strain PM38 further supported the potential to degrade OPs. In addition, inoculating cotton seedlings with PM38 improved root length under stressful conditions. Inoculation of strain PM38 reduces stress by minimizing proline, thiobarbituric acid–reactive compounds, and electrolyte leakage. The strain PM38 has the potential to be a good multi-stress-tolerant option for a biological pest control agent capable of improving global food security and managing contaminated sites. [ABSTRACT FROM AUTHOR]

Copyright of Anbar Journal of Agricultural Sciences is the property of Republic of Iraq Ministry of Higher Education & Scientific Research (MOHESR) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Potassium (K) is an essential macronutrient for plant development. Although the low-K+-responsive calcium (Ca2+) signaling pathway is known, its regulator remained elusive. Li et al. recently demonstrated that the target of rapamycin complex (TORC) and Ca2+ signaling pathways show reciprocal regulation of K+-responsive growth in plants. [ABSTRACT FROM AUTHOR]

Mepiquat chloride (1,1-dimethyl piperidinium chloride, DPC) is a representative plant growth regulator which can regulate the source-sink relationship for yield increase and shape ideal plant type for mechanical cultivation. Here we show a DPC adsorbed layered double hydroxide (DPC-LDH) architecture with enhanced controlled release property and soil distribution. By drip irrigation on cotton, it makes total dosage of DPC reduced from 270 to 90 g/ha, while the frequency decreased from 5 to 2 times. The unique supramolecular interaction is confirmed as the basis of controlled release behavior. Moreover, except for the physical resistance to the sedimentation brought by the lamellar LDH, the enhanced electrostatic interaction makes DPC-LDH the dominant distribution in soil. It improves the efficiency of DPC molecules absorbed by cotton plants and greatly saves the inputs in labor and chemicals. This method is expected to achieve the yield increase and agricultural sustainability by energy saving and emission reduction.

The WUSCHEL-related homeobox (WOX) transcription factor plays a vital role in stem cell maintenance and organ morphogenesis, which are essential processes for plant growth and development. Dendrobium chrysotoxum, D. huoshanense, and D. nobile are valued for their ornamental and medicinal properties. However, the specific functions of the WOX gene family in Dendrobium species are not well understood. In our study, a total of 30 WOX genes were present in the genomes of the three Dendrobium species (nine DchWOXs, 11 DhuWOXs, and ten DnoWOXs). These 30 WOXs were clustered into ancient clades, intermediate clades, and WUS/modern clades. All 30 WOXs contained a conserved homeodomain, and the conserved motifs and gene structures were similar among WOXs belonging to the same branch. D. chrysotoxum and D. huoshanense had one pair of fragment duplication genes and one pair of tandem duplication genes, respectively; D. nobile had two pairs of fragment duplication genes. The cis-acting regulatory elements (CREs) in the WOX promoter region were mainly enriched in the light response, stress response, and plant growth and development regulation. The expression pattern and RT-qPCR analysis revealed that the WOXs were involved in regulating the floral organ development of D. chrysotoxum. Among them, the high expression of DchWOX3 suggests that it might be involved in controlling lip development, whereas DchWOX5 might be involved in controlling ovary development. In conclusion, this work lays the groundwork for an in-depth investigation into the functions of WOX genes and their regulatory role in Dendrobium species' floral organ development. [ABSTRACT FROM AUTHOR]

Bulbil is an important asexual reproductive structure of bulbil plants. It mainly grows in leaf axils, leaf forks, tubers and the upper and near ground ends of flower stems of plants. They play a significant role in the reproduction of numerous herbaceous plant species by serving as agents of plant propagation, energy reserves, and survival mechanisms in adverse environmental conditions. Despite extensive research on bulbil-plants regarding their resources, development mechanisms, and utilisation, a comprehensive review of bulbil is lacking, hindering progress in exploiting bulbil resources. This paper provides a systematic overview of bulbil research, including bulbil-plant resources, identification of development stages and maturity of bulbils, cellular and molecular mechanisms of bulbil development, factors influencing bulbil development, gene research related to bulbil development, multi-bulbil phenomenon and its significance, medicinal value of bulbils, breeding value of bulbils, and the application of plant tissue culture technology in bulbil production. The application value of the Temporary Immersion Bioreactor System (TIBS) and Terahertz (THz) in bulbil breeding is also discussed, offering a comprehensive blueprint for further bulbil resource development. Additionally, additive, seven areas that require attention are proposed: (1) Utilization of modern network technologies, such as plant recognition apps or websites, to collect and identify bulbous plant resources efficiently and extensively; (2) Further research on cell and tissue structures that influence bulb cell development; (3) Investigation of the network regulatory relationship between genes, proteins, metabolites, and epigenetics in bulbil development; (4) Exploration of the potential utilization value of multiple sprouts, including medicinal, ecological, and horticultural applications; (5) Innovation and optimization of the plant tissue culture system for bulbils; (6) Comprehensive application research of TIBS for large-scale expansion of bulbil production; (7) To find out the common share genetics between bulbils and flowers. [ABSTRACT FROM AUTHOR]

The highly phosphorylated nucleotide, guanosine tetraphosphate (ppGpp), functions as a secondary messenger in bacteria and chloroplasts. The accumulation of ppGpp alters plastidial gene expression and metabolism, which are required for proper photosynthetic regulation and robust plant growth. However, because four plastid-localized ppGpp synthases/hydrolases function redundantly, the impact of the loss of ppGpp-dependent stringent response on plant physiology remains unclear. We used CRISPR/Cas9 technology to generate an Arabidopsis thaliana mutant lacking all four ppGpp synthases/hydrolases and characterized its phenotype. The mutant showed over 20-fold less ppGpp levels than the wild type under normal growth conditions and exhibited leaf chlorosis and increased expression of defense-related genes as well as salicylic acid and jasmonate levels upon transition to nitrogen-starvation conditions. These results demonstrate that proper levels of ppGpp in plastids are required for controlling not only plastid metabolism but also phytohormone signaling, which is essential for plant defense. [ABSTRACT FROM AUTHOR]

The plant-specific NAC gene family is one of the largest transcription factor families, participating in plant growth regulation and stress response. Despite extensive characterization in various plants, our knowledge of the NAC family in oat is lacking. Herein, we identified 333 NAC genes from the latest release of the common oat genome. We provide a comprehensive overview of the oat NAC gene family, covering gene structure, chromosomal localization, phylogenetic characteristics, conserved motif compositions, and gene duplications. AsNAC gene expression in different tissues and the response to various abiotic stresses were characterized using RT-qPCR. The main driver of oat NAC gene family expansion was identified as segmental duplication using collinearity analysis. In addition, the functions of AsNAC109 in regulating abiotic stress tolerance in Arabidopsis were clarified. This is the first genome-wide investigation of the NAC gene family in cultivated oat, which provided a unique resource for subsequent research to elucidate the mechanisms responsible for oat stress tolerance and provides valuable clues for the improvement of stress resistance in cultivated oat. [ABSTRACT FROM AUTHOR]

Dragon fruit (Hylocereus sp.) is an exotic crop with a great potential for its cultivation in semi arid tracts throughout India. Its planting is mainly confined to harsh climates and degraded lands facing challenges in its establishment. Hence, availability of quality planting material is essential for attaining success. Due to long juvenile phase of the sexually propagated seedlings it can be propagated asexually by stem cuttings but proper rooting is not possible without exogenous auxin application. Hence, during 2022- 2023 a research was carried out at the Horticultural Experimental area of Khalsa College, Amritsar to standardize the concentration of plant growth regulators viz. IBA, NAA and PHB for rooting and success rate in stem cuttings comprising of sixteen treatments with three replications arranged in randomized block design. The results revealed that the stem cuttings treated with IBA 4000 ppm proved to be superior for the sprouting and survival of the cuttings resulting in the improved vegetative growth with profuse, longer, thicker and the heaviest roots. Hence, the cutting treatment of IBA 4000 ppm can be proposed for dragon fruit plant propagation to meet the market demand in India. [ABSTRACT FROM AUTHOR]

Plant roots are constantly prepared to adjust their growth trajectories to avoid unfavorable environments, and their ability to reorient is particularly crucial for survival. Under laboratory conditions, this continuous reorientation of the root tip is manifested as coiling or waving, which we refer to as root circumnutation. However, the effect of ambient temperature (AT) on root circumnutation remains unexplored. In this study, rice seedlings were employed to assess the impact of varying ATs on root circumnutation. The role of ethylene in mediating root circumnutation under elevated AT was examined using the ethylene biosynthesis inhibitor aminooxyacetic acid (AOA) and the ethylene perception antagonist silver thiosulfate (STS). Furthermore, transcriptome sequencing, weighted gene co-expression network analysis, and real-time quantitative PCR were utilized to analyze gene expressions in rice root tips under four distinct treatments: 25°C, 35°C, 35°C+STS, and 35°C+AOA. As a result, genes associated with ethylene synthesis and signaling (OsACOs and OsERFs), auxin synthesis and transport (OsYUCCA6, OsABCB15, and OsNPFs), cell elongation (OsEXPAs, OsXTHs, OsEGL1, and OsEXORDIUMs), as well as the inhibition of root curling (OsRMC) were identified. Notably, the expression levels of these genes increased with rising temperatures above 25°C. This study is the first to demonstrate that elevated AT can induce root circumnutation in rice via the ethylene pathway and proposes a potential molecular model through the identification of key genes. These findings offer valuable insights into the growth regulation mechanism of plant roots under elevated AT conditions. [ABSTRACT FROM AUTHOR]

Introduction: Plant growth is a plastic phenomenon controlled both by endogenous genetic programs and by environmental cues. The embryonic stem, the hypocotyl, is an ideal model system for the quantitative study of growth due to its relatively simple geometry and cellular organization, and to its essentially unidirectional growth pattern. The hypocotyl of Arabidopsis thaliana has been studied particularly well at the molecular-genetic level and at the cellular level, and it is the model of choice for analysis of the shade avoidance syndrome (SAS), a growth reaction that allows plants to compete with neighboring plants for light. During SAS, hypocotyl growth is controlled primarily by the growth hormone auxin, which stimulates cell expansion without the involvement of cell division. Methods: We assessed hypocotyl growth at cellular resolution in Arabidopsis mutants defective in auxin transport and biosynthesis and we designed a mathematical auxin transport model based on known polar and non-polar auxin transporters (ABCB1, ABCB19, and PINs) and on factors that control auxin homeostasis in the hypocotyl. In addition, we introduced into the model biophysical properties of the cell types based on precise cell wall measurements. Results and Discussion: Our model can generate the observed cellular growth patterns based on auxin distribution along the hypocotyl resulting from production in the cotyledons, transport along the hypocotyl, and general turnover of auxin. These principles, which resemble the features of mathematical models of animal morphogen gradients, allow to generate robust shallow auxin gradients as they are expected to exist in tissues that exhibit quantitative auxin-driven tissue growth, as opposed to the sharp auxin maxima generated by patterning mechanisms in plant development. [ABSTRACT FROM AUTHOR]

Strigolactone (SL) biosynthesis inhibitors have shown impressive activity in increasing shoot branching and inhibiting seed germination of the root parasitic plants Striga spp. and Orobanche spp. Herein, novel 1H-1,2,4-triazole derivatives were designed as SL biosynthesis inhibitors based on the backbone modification strategy, 33 target compounds were chemical synthesized and screened on Arabidopsis thaliana and Oryza sativa. The structure–activity relationship analysis enabled the discovery of a potential SL biosynthesis inhibitor B4 with the promising activity in increasing shoot branching, elongating taproot by inhibiting the biosynthesis of 4-deoxyorobanchol (4DO). We further found that B4-treated A. thaliana showed increased branching phenotype with the upregulated gene expression of AtMAX3 and AtMAX4. These results indicated that B4 might be a potent SL biosynthesis inhibitor and provide a unique scaffold for the development of new SL biosynthesis inhibitors. [ABSTRACT FROM AUTHOR]

Several closely related Myb‐like activator proteins are known to have partially redundant functions within the plant circadian clock, but their specific roles are not well understood. To clarify the function of the REVEILLE 4, REVEILLE 6, and REVEILLE 8 transcriptional activators, we characterized the growth and clock phenotypes of CRISPR‐Cas9‐generated single, double, and triple rve mutants. We found that these genes act synergistically to regulate flowering time, redundantly to regulate leaf growth, and antagonistically to regulate hypocotyl elongation. We previously reported that increasing intensities of monochromatic blue and red light have opposite effects on the period of triple rve468 mutants. Here, we further examined light quality‐specific phenotypes of rve mutants and report that rve468 mutants lack the blue light‐specific increase in expression of some circadian clock genes observed in wild type. To investigate the basis of these blue light‐specific circadian phenotypes, we examined RVE protein abundances and degradation rates in blue and red light and found no significant differences between these conditions. We next examined genetic interactions between RVE genes and ZEITLUPE and ELONGATED HYPOCOTYL5, two factors with blue light‐specific functions in the clock. We found that the RVEs interact additively with both ZEITLUPE and ELONGATED HYPOCOTYL5 to regulate circadian period, which suggests that neither of these factors are required for the blue light‐specific differences that we observed. Overall, our results suggest that the RVEs have separable functions in plant growth and circadian regulation and that they are involved in blue light‐specific circadian signaling via a novel mechanism. [ABSTRACT FROM AUTHOR]

Root growth in Arabidopsis is inhibited by exogenous auxin–amino acid conjugates, and mutants resistant to one such conjugate [indole-3-acetic acid (IAA)–Ala] map to a gene (AtIAR1) that is a member of a metal transporter family. Here, we test the hypothesis that AtIAR1 controls the hydrolysis of stored conjugated auxin to free auxin through zinc transport. AtIAR1 complements a yeast mutant sensitive to zinc, but not manganese- or iron-sensitive mutants, and the transporter is predicted to be localized to the endoplasmic reticulum/Golgi in plants. A previously identified Atiar1 mutant and a non-expressed T-DNA mutant both exhibit altered auxin metabolism, including decreased IAA–glucose conjugate levels in zinc-deficient conditions and insensitivity to the growth effect of exogenous IAA–Ala conjugates. At a high concentration of zinc, wild-type plants show a novel enhanced response to root growth inhibition by exogenous IAA–Ala which is disrupted in both Atiar1 mutants. Furthermore, both Atiar1 mutants show changes in auxin-related phenotypes, including lateral root density and hypocotyl length. The findings therefore suggest a role for AtIAR1 in controlling zinc release from the secretory system, where zinc homeostasis plays a key role in regulation of auxin metabolism and plant growth regulation. [ABSTRACT FROM AUTHOR]

Key message: The creeping bentgrass small heat shock protein AsHSP26.2 positively regulates plant growth and is a novel candidate for use in crop genetic engineering for enhanced biomass production and grain yield. Small heat shock proteins (sHSPs), a family of proteins with high level of diversity, significantly influence plant stress tolerance and plant development. We have cloned a creeping bentgrass chloroplast-localized sHSP gene, AsHSP26.2 responsive to IAA, GA and 6-BA stimulation. Transgenic creeping bentgrass overexpressing AsHSP26.2 exhibited significantly enhanced plant growth with increased stolon number and length as well as enlarged leaf blade width and leaf sheath diameters, but inhibited leaf trichomes initiation and development in the abaxial epidermis. These phenotypes are completely opposite to those displayed in the transgenic plants overexpressing AsHSP26.8, another chloroplast sHSP26 isoform that contains additional seven amino acids (AEGQGDG) between the consensus regions III and IV (Sun et al., Plant Cell Environ 44:1769–1787, 2021). Furthermore, AsHSP26.2 overexpression altered phytohormone biosynthesis and signaling transduction, resulting in elevated auxin and gibberellins (GA) accumulation. The results obtained provide novel insights implicating the sHSPs in plant growth and development regulation, and strongly suggest AsHSP26.2 to be a novel candidate for use in crop genetic engineering for enhanced plant biomass production and grain yield. [ABSTRACT FROM AUTHOR]

Precise knowledge of all aspects controlling plant tissue culture and in vitro plant regeneration is crucial for plant biotechnologists and their correlated industry, as there is increasing demand for this scientific knowledge, resulting in more productive and resilient plants in the field. However, the development and application of cell and tissue culture techniques are usually based on empirical studies, although some data-driven models are available. Overall, the success of plant tissue culture is dependent on several factors such as available nutrients, endogenous auxin synthesis, organic compounds, and environment conditions. In this review, the most important aspects are described one by one, with some practical recommendations based on basic research in plant physiology and sharing our practical experience from over 20 years of research in this field. The main aim is to help new plant biotechnologists and increase the impact of the plant tissue culture industry worldwide. [ABSTRACT FROM AUTHOR]

Apple fire blight, caused by the bacterium Erwinia amylovora, is a devastating disease of apple and pear trees. Biological control methods have attracted much attention from researchers to manage plant diseases as they are eco-friendly and viable alternatives to synthetic pesticides. Herein, we isolated Streptomyces sp. JCK-8055 from the root of pepper and investigated its mechanisms of action against E. amylovora. Streptomyces sp. JCK-8055 produced aureothricin and thiolutin, which antagonistically affect E. amylovora. JCK-8055 and its two active metabolites have a broad-spectrum in vitro activity against various phytopathogenic bacteria and fungi. They also effectively suppressed tomato bacterial wilt and apple fire blight in in vivo experiments. Interestingly, JCK-8055 colonizes roots as a tomato seed coating and induces apple leaf shedding at the abscission zone, ultimately halting the growth of pathogenic bacteria. Additionally, JCK-8055 can produce the plant growth regulation hormone indole-3-acetic acid (IAA) and hydrolytic enzymes, including protease, gelatinase, and cellulase. JCK-8055 treatment also triggered the expression of salicylate (SA) and jasmonate (JA) signaling pathway marker genes, such as PR1, PR2, and PR3. Overall, our findings demonstrate that Streptomyces sp. JCK-8055 can control a wide range of plant diseases, particularly apple fire blight, through a combination of mechanisms such as antibiosis and induced resistance, highlighting its excellent potential as a biocontrol agent. Key points: • JCK-8055 produces the systemic antimicrobial metabolites, aureothricin, and thiolutin. • JCK-8055 treatment upregulates PR gene expression in apple plants against E. amylovora. • JCK-8055 controls plant diseases with antibiotics and induced resistance. [ABSTRACT FROM AUTHOR]

Activation of γ-aminobutyric acid (GABA) shunt pathway and upregulation of dehydrins are involved in metabolic homeostasis and protective mechanisms against drought stress. Seed germination percentage, seedling growth, levels of GABA, alanine, glutamate, malondialdehyde (MDA), and the expression of glutamate decarboxylase (GAD) and dehydrin (dhn and wcor) genes were examined in post-germination and seedlings of four durum wheat (Triticum durum L.) cultivars in response to water holding capacity levels (80%, 50%, and 20%). Data showed a significant decrease in seed germination percentage, seedling length, fresh and dry weight, and water content as water holding capacity level was decreased. Levels of GABA, alanine, glutamate, and MDA were significantly increased with a negative correlation in post-germination and seedling stages as water holding capacity level was decreased. Prolonged exposure to drought stress increased the GAD expression that activated GABA shunt pathway especially at seedlings growth stage to maintain carbon/nitrogen balance, amino acids and carbohydrates metabolism, and plant growth regulation under drought stress. The mRNA transcripts of dhn and wcor significantly increased as water availability decreased in all wheat cultivars during the post-germination stage presumably to enhance plant tolerance to drought stress by cell membrane protection, cryoprotection of enzymes, and prevention of reactive oxygen species (ROS) accumulation. This study showed that the four durum wheat cultivars responded differently to drought stress especially during the seedling growth stage which might be connected with ROS scavenging systems and the activation of antioxidant enzymes that were associated with activation of GABA shunt pathway and the production of GABA in durum seedlings. [ABSTRACT FROM AUTHOR]

Soil salinity is one of the major limiting factors in plant growth regulation. Salinity-tolerant endophytic bacteria (STEB) can be used to alleviate the negative effects of salinity and promote plant growth. In this study, thirteen endophytic bacteria were isolated from mungbean roots and tested for NaCl salt-tolerance up to 4%. Six bacterial isolates, TMB2, TMB3, TMB5, TMB6, TMB7 and TMB9, demonstrated the ability to tolerate salt. Plant growth-promoting properties such as phosphate solubilization, indole-3-acetic acid (IAA) production, nitrogen fixation, zinc solubilization, biofilm formation and hydrolytic enzyme production were tested in vitro under saline conditions. Eight bacterial isolates indicated phosphate solubilization potential ranging from 5.8-17.7 µg mL-1, wherein TMB6 was found most efficient. Ten bacterial isolates exhibited IAA production ranging from 0.3-2.1 µg mL-1, where TMB7 indicated the highest potential. All the bacterial isolates except TMB13 exhibited nitrogenase activity. Three isolates, TMB6, TMB7 and TMB9, were able to solubilize zinc on tris-minimal media. All isolates were capable of forming biofilm except TMB12 and TMB13. Only TMB2, TMB6 and TMB7 exhibited cellulase activity, while TMB2 and TMB7 exhibited pectinase production. Based on in vitro testing, six efficient STEB were selected and subjected to the further studies. 16S rRNA gene sequencing of efficient STEB revealed the maximum similarity between TMB2 and Rhizobium pusense, TMB3 and Agrobacterium leguminum, TMB5 and Achromobacter denitrificans, TMB6 and Pseudomonas extremorientalis, TMB7 and Bradyrhizobium japonicum and TMB9 and Serratia quinivorans. This is the first international report on the existence of A. leguminum, A. denitrificans, P. extremorientalis and S. quinivorans inside the roots of mungbean. Under controlled-conditions, inoculation of P. extremorientalis TMB6, B. japonicum TMB7 and S. quinivorans TMB9 exhibited maximum potential to increase plant growth parameters; specifically plant dry weight was increased by up to 52%, 61% and 45%, respectively. Inoculation of B. japonicum TMB7 displayed the highest potential to increase plant proline, glycine betaine and total soluble proteins contents by 77%, 78% and 64%, respectively, compared to control under saline conditions. It is suggested that the efficient STEB could be used as biofertilizers for mungbean crop productivity under saline conditions after field-testing. [ABSTRACT FROM AUTHOR]

This study aimed to determine the effects of plant growth regulators and different medium on in vitro propagation of 'Hayward' and 'Zespri Gold' kiwifruits. Microcuttings were used as explant sources and cultured in MS and WPM medium containing different concentrations of BA and GA3. Subcultures were carried out at intervals of 4-6 weeks. Contamination rate (%), blackening rate (%), callus development rate (%), shoot rate (%), and propagation coefficient (plantlet/explant) were determined. The micropropagation experiment was carried out according to the randomized plot design. The arc-sin transformation was applied to the percentage values before analysis. Significance levels of the means were compared with the LSD test. It was determined that 0.1% mercury chloride application increased the sterilization efficiency. As the BA concentration in the medium increased, the rate of callus formation of the explants increased. While there was no difference in shoot rates of explants cultured on MS and WPM medium, the propagation rate was higher in MS medium. The propagation coefficient of the 'Hayward' kiwi cultivar was 3.08 in MS medium containing 1.0 mgL-1 BA + 0.5 mgL-1 GA3. MS medium can be recommended as a basic medium for in vitro kiwi propagation. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the effects of Putrescine and Indole-3-Butyric Acid (IBA) on the adventitious rooting of micro-cuttings and semi-hardwood cutting of Rosa damascena, this study was conducted under both in vitro and in vivo conditions. Research Method: The rooting of micro-cuttings was induced on the basal MS medium supplemented with five concentrations (0, 0.25, 0.5, 1 and 2 mg/L) of IBA and putrescine. In vivo experiment, putrescine and IBA at five concentrations (0, 0.25, 0.5, 1 and 2 g/L) were applied on semi-hardwood damask cuttings, while a downward wounding was created by a sharp blade on the bases of cutting as another treatment. Findings: Data showed significant variations in the root number and root length for in vitro and in vivo cuttings treated with different concentrations of putrescine and IBA. The obtained results revealed that presence of putrescine and IBA in both conditions enhanced root formation, as significantly improved the number of roots and root length in each explant. Under in vitro conditions, the maximum root length and root number were observed on the MS medium supplemented with 1 mg/l IBA+1 mg/l putrescine. Research limitations: No limitations were found. Originality/Value: The present study highlighted the role of putrescine and IBA in the adventitious rooting of R. damascena, under both in vitro and in vivo situations. [ABSTRACT FROM AUTHOR]

Rice fields are one of the important anthropogenic sources of methane emissions. Methanotrophs dwelling near the rice roots and at the oxic–anoxic interface of paddy fields can oxidize a large fraction of the generated methane and are therefore considered to be important. Nitrogen fixation in rice root-associated methanotrophs is well known. Our aim in this study was to explore the potential of methanotrophs as bio-inoculants for rice and the studies were performed in pot experiments in monsoon. Ten indigenously isolated methanotrophs were used belonging to eight diverse genera of Type Ia, Type Ib, and Type II methanotrophs, including the newly described genera and/or species, Methylocucumis oryzae and Methylolobus aquaticus, as well as Ca. Methylobacter oryzae and Ca. Methylobacter coli. Additionally, two consortia (Methylomonas strains and Methylocystis-Methylosinus strains) were used. Nitrogen fixation pathways or nifH genes were detected in all of the used methanotrophs. Plant growth promotion (PGPR) was seen in terms of increased plant height and grain yield. Nine out of twelve (seven single strains and two consortia) showed positive effects on grain yield (6–38%). The highest increase in grain yield was seen after inoculation with Ca. Methylobacter coli (38%) followed by Methylomonas consortium (35%) and Methylocucumis oryzae (31%). Methylomagnum ishizawai inoculated plants showed the highest plant height. Methylocucumis oryzae inoculated plants showed early flowering, grain formation, and grain maturation (~17–18 days earlier). In all the pot experiments, minimal quantities of nitrogen fertilizer were used with no additional organic fertilizer inputs. The present study demonstrated the possibility of developing methanotrophs as bio-inoculants for rice agriculture, which would promote plant growth under low inputs of nitrogenous fertilizers. Although the effect of methanotrophs on methane mitigation is still under investigation, their application to reduce methane emissions from rice fields could be an added advantage. [ABSTRACT FROM AUTHOR]

Rice is widely cultivated worldwide, and beneficial bactrial colonization are particularly desirable for sustainable agriculture because they promote growth and production by preventing excessive heavy metal contamination. The present study was conducted with the aim of improving the growth of rice seedlings (MTU1010 variety) under copper (Cu) stress by using Cu-tolerant plant growth promoting bacteria (PGPB) Micrococcus yunnanensis GKSM13. Strain GKSM13 was able to produce plant growth promoting factors (PGPFs) such as indole-3-acetic acid (IAA), gibberellin A3 (GA3) and ammonia, accumulate proline, fix N2, and inhibit 2,2-Diphenyl-1-picrylhydrazyl (DPPH). Rice seedlings treated with Cu2+ and co-inoculated with GKSM13 significantly improved their growth in morphological and biochemical aspects. When analysed by field emission scanning electron microscope (FE-SEM), GKSM13 was found to be associated with the root cells in the form of large number of coccoid cells. The uptake of Cu2+ in rice seedlings was reduced to 57.5% in the presence of GKSM13. Strain GKSM13 treatment also reduced Cu-induced oxidative stress of rice seedlings by activating antioxidant enzymes including superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APOX) and glutathione peroxidase (GPOX), which was supported by DPPH inhibition and reduction of malondialdehyde (MDA) accumulation. Insight into the genome of strain GKSM13 reveals the presence of tryptophan (trp), ent-kaurene, cyanase (cyn), phosphate-specific transport (pst), major facilitator superfamily transporter (MFS), sulphate transporter (cys), proline (pro) and SOD (sod) genes, which are responsible for promoting plant growth and alleviating Cu2+ stress. Therefore, the application of strain M. yunnanensis GKSM13 could provide a sustainable agricultural solution for Cu-affected mining areas.

This editorial titled "Hormones and biostimulants in plants: physiological and molecular insights on plant stress responses" explores the impact of biotic and abiotic stress signals on cultivated crops. It focuses on the use of biostimulants, substances or microorganisms that enhance plant nutrition, quality, fitness, and stress tolerance. The editorial discusses the role of phytohormones and their interaction with biostimulants in modifying gene activity, metabolic pathways, and antioxidant systems in plants under stress conditions. It includes research articles and reviews on the effects of phytohormones and biostimulants on plant stress responses, particularly in relation to drought, salinity, and heat. The text also covers various aspects of plant stress responses, such as salt stress, acidification stress, and biotic stresses, and highlights the importance of environmentally friendly strategies for sustainable agricultural production. [Extracted from the article]

Aim. To synthesize new 1-alkyl-3-polyfluoroalkyl-1,3-dihydrobenzimidazole-2-selenones and study their biological activity as potential plant growth regulators. Results and discussion. 1-Alkyl-3-polyfluoroalkyl-1,3-dihydrobenzimidazole-2-selenones were obtained from the corresponding 1-alkyl-3-polyfluoroalkylbenzimidazolium iodides by the action of elemental selenium in the presence of a base. The preliminary biological tests for the growth-regulating activity of the compounds obtained were conducted. Experimental part. The structure of the compounds synthesized was proven by 1H and 19F NMR spectroscopy methods, as well as by the elemental analysis. The biological studies were done on model plants of winter wheat of the “bezosta” variety. Conclusions. A convenient method for obtaining 1-alkyl-3-polyfluoroalkyl-1,3-dihydro-benzimidazole-2-selenones has been developed. Biological studies have shown that the compounds synthesized have a diverse effect on the plant growth.

The protein phosphatase 2C (PP2C), a key regulator of the ABA signaling pathway, plays important roles in plant growth and development, hormone signaling, and abiotic stress response. Although the PP2C gene family has been identified in many species, systematic analysis was still relatively lacking in ramie (Boehmeria nivea L.). In the present study, we identified 63 BnPP2C genes from the ramie genome, using bioinformatics analysis, and classified them into 12 subfamilies, and this classification was consistently supported by their gene structures and conserved motifs. In addition, we observed that the functional differentiation of the BnPP2C family of genes was restricted and that fragment replication played a major role in the amplification of the BnPP2C gene family. The promoter cis-regulatory elements of BnPP2C genes were mainly involved in light response regulation, phytohormone synthesis, transport and signaling, environmental stress response and plant growth and development regulation. We identified BnPP2C genes with tissue specificity, using ramie transcriptome data from different tissues, in rhizome leaves and bast fibers. The qRT-PCR results showed that the BnPP2C1, BnPP2C26 and BnPP2C27 genes had a strong response to drought, high salt and ABA, and there were a large number of stress-responsive elements in the promoter region of BnPP2C1 and BnPP2C26. The results suggested that BnPP2C1 and BnPP2C26 could be used as the candidate genes for drought and salt tolerance in ramie. These results provide a reference for further studies on the function of the PP2C gene and advance the development of the mechanism of ramie stress response, with a view to providing candidate genes for the molecular breeding of ramie for drought and salt tolerance. [ABSTRACT FROM AUTHOR]

This article, published in the journal Environment & Ecology, provides information on the distribution, damage, and management of guava sucking pests, focusing on the two-tailed mealybug. The study found that the Lucknow 49 variety of guava was most affected by sucking pests, with the population of the two-tailed mealybug being highest in February. Weather parameters such as temperature and rainfall were found to be correlated with the population of sucking pests. The study also evaluated the effectiveness of different treatments, with Acetamiprid 20% SP showing the highest mortality rate for the two-tailed mealybug. Overall, this document offers valuable insights into the distribution, damage, and management of major sucking pests affecting guava plants. [Extracted from the article]

This article explores the impact of plant growth regulators and nano zinc on the growth and yield of wheat. The study was conducted in Prayagraj, India and found that the application of Nano zinc 120 ppm + Salicylic acid 400 mg/l resulted in higher growth parameters and superior yield parameters. The study suggests that using plant growth regulators and nano zinc can enhance wheat growth and yield. The combination of Nano zinc and Salicylic acid was found to be particularly effective in improving plant dry weight, number of tillers per hill, and test weight. [Extracted from the article]

Histones are the basic structural proteins that make up chromatin. The amino acid sequence of histone H3 is highly conserved, and it plays an important role in maintaining chromatin stability, regulating plant growth and development, and responding to environmental changes. In order to explore the structure and function of the histone H3 gene family in foxtail millet, and lay a theoretical foundation for further research on the biological function of histone H3 in foxtail millet, in this study, 15 histone H3 genes from the xiaomi and Yugu 1(YG1) genomes were identified, and named sequentially as SiH3.1-SiH3.15. Furthermore, comparative and analytical studies were conducted using bioinformatics techniques to investigate the distribution on chromosomes, phylogenetic relationships, gene structure, conserved motifs, conserved domains, promoter cis-acting elements, subcellular localization, and tissue expression patterns of SiH3 genes. The results showed that, except for SiH3.2 and SiH3.13 in xiaomi, and SiH3.10.1 and SiH3.11.1 in YG1, the other genes were located in corresponding positions on chromosomes. Phylogenetic analysis revealed that SiH3 genes could be classified into four categories, with 6, 1, 6, and 2 genes in each category for xiaomi, and 4, 2, 7, and 2 genes in each category for YG1. Genes within the same subgroup in the two varieties exhibited similar gene structure, conserved motifs, and domains. They were localized in the cell nucleus according to subcellular localization. Promoter cis-acting elements were mainly associated with plant growth and development regulation and stress responses. Expression pattern analysis showed that SiH3.7 and SiH3.15, belonging to the H3.3 subgroup, exhibited constitutive high expression in different tissues, with significantly higher expression levels in the spike than in other tissues, indicating their important role in foxtail millet throughout its growth, especially at reproductive stages, and suggesting their significant potential applications in foxtail millet production. [ABSTRACT FROM AUTHOR]

This article explores the impact of plant growth regulators on the growth and yield of sweet peppers. The study, conducted in Southern Odisha, used a Randomized Block Design with seven treatments. The results revealed that different growth regulators had varying effects on plant height, fruiting branches, fruit weight, and yield. The study concluded that the application of BA (5 ppm) resulted in the highest fruit yield and early harvesting, which could be beneficial for farmers. Overall, the use of growth regulators at the flowering stage enhanced plant growth and development, leading to increased fruit yield. [Extracted from the article]

Drought is one of the most important factors that limit crop yield. In this study, the growth promotive activity of terrein, a microbial metabolite, on four selected agricultural plants (Vigna radiata, Brassica chinensis, Triticum aestivum and Sorghum bicolor) under drought conditions was assessed via pot experiment. Terrein effectively stimulated the seedling growth of tested species and increased their fresh and dry weight at low concentrations (2 and 10 μg/mL), either applied as a seed soaking agent or a spray solution, especially on root growth. The maximum stimulatory effect on root growth was observed on B. chinensis seedlings (99.20%), on fresh weight was found on T. aestivum seedlings (97.23%), and on dry weight was discovered on V. radiata seedlings (58.33%), implying that this stimulatory effect was species-specific. Further study revealed that the application of terrein significantly raised the contents of GA3, IAA and CTK; meanwhile, MDA content declined significantly, whereas the activity of POD, CAT and SOD was boosted significantly, suggesting that terrein can stimulate plant growth by reducing the production of ROS. Our work is the first study focusing on terrein's plant growth promotive activity, indicating terrein has the potential to be further explored as an environment-friendly growth regulator. [ABSTRACT FROM AUTHOR]

Wollemi pine (Wollemia nobilis (Jones, Hill, Allen)) is a living fossil, known only through fossil records until its 1994 discovery in Australia. Wollemi Pine is closely related to Norfolk Island pine (Araucaria heterophylla (Salisb.) Franco), making it an interesting system to study metabolic evolution. We employed untargeted liquid chromatography mass spectrometry-based (LC-MS) metabolomics, with chemometrics, pathway analysis, and our novel plant growth regulator (PGR) putative identification tool (HormonomicsDB), to explore the metabolomes of both species. We identified PGR conjugates and found cytokinin, zeatin, and brassinosteroid pathways to be overrepresented in Wollemi pine tissues, suggesting these PGRs play an important role in its survival. Melatonin, a proposed ancient and stress-related PGR, was not identified in untargeted analysis of either species. Based on our untargeted results, we employed targeted LC-MS to quantify brassinolide and confirm the absence or presence of melatonin in Wollemi and Norfolk Island pine. Both species had similar concentrations of brassinolide, while Wollemi pine had significantly higher melatonin levels than Norfolk Island pine. High levels of melatonin and brassinolide in Wollemi pine supports the hypothesis that these are ancient PGRs that conferred an evolutionary advantage in Wollemi, allowing it to persist. [ABSTRACT FROM AUTHOR]

Tomato (Solanum lycopersicum) is one of the most important vegetable crops in the world and abiotic stresses often cause serious problems in tomato production. It is thus important to identify new regulators in stress response and to devise new approaches to promote stress tolerance in tomato. Previous studies have shown that small secreted peptides (SSPs) are important signal molecules regulating plant growth and stress response by mediating intercellular communication. However, little is known about tomato SSPs, especially their roles in responding to abiotic stresses. Here we report the identification of 1,050 putative SSPs in the tomato genome, 557 of which were classified into 38 known SSP families based on their conserved domains. GO and transcriptome analyses revealed that a large proportion of SlSSPs might be involved in abiotic stress response. Further analysis indicated that stress response related cis-elements were present on the SlCEP promotors and a number of SlCEPs were significantly upregulated by drought treatments. Among the drought-inducible SlCEPs, SlCEP10 and SlCEP11b were selected for further analysis via exogenous application of synthetic peptides. The results showed that treatments with both SlCEP10 and SlCEP11b peptides enhanced tomato drought stress tolerance, indicating the potential roles of SlSSPs in abiotic stress response. [ABSTRACT FROM AUTHOR]

The phytohormone abscisic acid (ABA) is vital in regulating root elongation, seed germination, and abiotic stress responses in plants. Conversely, the mechanisms of ABA in mulberry root growth, seed germination, and abiotic stress responses are poorly understood. Here, we reported that exogenous ABA and drought treatment inhibited the growth of mulberry seedlings but significantly increased the ratio of root/stem. Inhibition of ABA synthesis by fluridone and sodium tungstate resulted in the decrease of root/stem ratio. We also showed that the expression of MaNCED1 in the root was strongly induced by drought and salt stress. Increasing the expression of MaNCED1 in tobacco using overexpression leads to increased root elongation and reduced seed germination. Compared with the wild type, the accumulation of H2O2 and MDA was reduced, while the POD activity and proline content was increased in the transgenic plants after drought and salt treatment. Further studies revealed increased resistance to drought and salt stress in MaNCED1 overexpressed tobaccos. Meanwhile, the auxin and ethylene signal pathway-related gene expression levels increased in MaNCED1 overexpressed tobaccos. This study demonstrated the roles of mulberry MaNCED1 in regulating plant development and abiotic stress responses. It gave further insights into the coordinated regulation of ABA, auxin, and ethylene in seed growth and germination. [ABSTRACT FROM AUTHOR]