Cereal Crop Plants Research Articles

Cytokinin: An invisible warrior to spot blotch disease: A new proposal to way forward

Background of Abstract: Wheat is threatened by spot blotch disease causing considerable yield loss, with existing genotypes lacking resistance and the necessary nutrients. Cytokinins (CKs) are key phytohormones that not only regulate plant development but also play an important role during spot blotch disease and in the nutrient metabolic pathway of crop plants. Body of Abstract: Spot blotch disease, caused by Bipolaris sorokiniana syn. Helminthosporium sativum syn. Cochliobolus sativus is one of the dangerous diseases of wheat (Triticum aestivum L.) in Asia. Previous study identified the significant impact of zinc (Zn), sulfur(S), iron (Fe), nitrogen(N), potassium(P), and chlorine (Cl) fertilization on dipping the spot blotch acuteness in two wheat varieties Bhrikuti and Sonalika in Nepal. Cytokinins (CKs) are crucial phytohormones that not only control plant growth but also show a significant function during the nutrient metabolic pathway and in the stressed condition of the cereal crop plants. Lack of vital nutrients like Zn, S and Fe initiates severe injury of the body which is pleading the urgent requirement to improve the increase of these micronutrients in the cereal crop plant. Crop bio-fortification is one of the promising methods through which these nutrients could be boosted to a desirable volume. Cytokinin has a crucial role in controlling environmental stress and defense methods of plants. It is also discovered that it has an effect over Zn growth in cereal crop plants. Many studies identified that an augmentation of Zn, S and Fe in the seeds of the cereal crop plants ensuing the improvement of the root elongation which is also helpful for foraging nutrients to the innate ends of the soil and supports in the water absorbance in the drought area. Traveling micronutrients from the lithosphere through the root supports in the uptake of the micronutrients and transferring them to the cereal crop plants. Short Conclusion: This review is exploring a crop bio- fortification method containing CRISPR-Cas9 through breeding methods could be a significant job for spot blotch stress management and developing the desirable traits to boost the nutritional rate of wheat which would be beneficial for mankind.

Reducing Arsenic Uptake in Cereal Crop Plants with Sugarcane Waste Application: A Comparative Study on the Effects on Physiology, Biochemistry, and Grain Nutrient Status

Reducing Arsenic Uptake in Cereal Crop Plants with Sugarcane Waste Application: A Comparative Study on the Effects on Physiology, Biochemistry, and Grain Nutrient Status

Sydnone Imines: A Novel Class of Plant Growth Regulators

An increase in the yield of the main cereal crops in the context of global climate changes requires additional impacts on plants. Natural and synthetic plant growth regulators (PGRs) are used to increase plant productivity and reduce the injury level caused by abiotic stressors. There is a growing need for novel highly effective plant growth stimulants to exhibit their effects at low doses and to not pose an environmental threat or injury to the crop quality. The derivatives of sydnone imine (SI), a mesoionic heterocycle possessing a 1,2,3-oxadiazole core, have been used as medicines until now but have not been used for agricultural applications. Some SI derivatives have recently been found to exhibit PGR properties. Herein, we report on the study of the PGR potential of nine SI derivatives bearing variable substituents at N(3), C(4), and N6 positions of the heterocycle designed to disclose the “molecular structure-PGR activity” relationship in this family. The SI derivatives were used in a wide concentration range (10−9–10−4 mol/L) for a pre-sowing treatment of winter wheat (Triticum aestivum L., two cultivars) and maize (Zea mays L., two hybrids) seeds in germinating experiments. All compounds were found to affect the growth of the axial organs of germinants, with the growth-stimulating or -inhibitory effect as well as its rate being considerably different for wheat and maize and, in many cases, also for roots and shoots. In addition, a pronounced concentration dependence of the effect was disclosed for many cases. The features of the molecular structure of SIs affecting their growth-regulating properties were elucidated. Compounds 4, 6, 7, and 8, which had exhibited a growth-promoting effect in germinating experiments, were used at appropriate concentrations for pot experiments on the same crops. For all compounds, the experiments showed a stimulating effect on the growth of roots (up to 80%), shoots (up to 112%), leaf area (up to 113%), fresh weights of roots (up to 83%), and aerial parts of the plants (up to 87%) or only on some of these parameters. The obtained results show a healthy outlook for the use of SI derivatives as promoting agents for improving the growth of cereal crop plants.

A CRISPR way for accelerating cereal crop improvement: Progress and challenges.

Humans rely heavily on cereal grains as a key source of nutrients, hence regular improvement of cereal crops is essential for ensuring food security. The current food crisis at the global level is due to the rising population and harsh climatic conditions which prompts scientists to develop smart resilient cereal crops to attain food security. Cereal crop improvement in the past generally depended on imprecise methods like random mutagenesis and conventional genetic recombination which results in high off targeting risks. In this context, we have witnessed the application of targeted mutagenesis using versatile CRISPR-Cas systems for cereal crop improvement in sustainable agriculture. Accelerated crop improvement using molecular breeding methods based on CRISPR-Cas genome editing (GE) is an unprecedented tool for plant biotechnology and agriculture. The last decade has shown the fidelity, accuracy, low levels of off-target effects, and the high efficacy of CRISPR technology to induce targeted mutagenesis for the improvement of cereal crops such as wheat, rice, maize, barley, and millets. Since the genomic databases of these cereal crops are available, several modifications using GE technologies have been performed to attain desirable results. This review provides a brief overview of GE technologies and includes an elaborate account of the mechanisms and applications of CRISPR-Cas editing systems to induce targeted mutagenesis in cereal crops for improving the desired traits. Further, we describe recent developments in CRISPR-Cas-based targeted mutagenesis through base editing and prime editing to develop resilient cereal crop plants, possibly providing new dimensions in the field of cereal crop genome editing.

Role of Antioxidant Enzymes and Glutathione S-Transferase in Bromoxynil Herbicide Stress Tolerance in Wheat Plants.

Background: Numerous pesticides and herbicides used in excess cause oxidative stress in plants. These chemicals protect plants from weeds and pests, but they also have very negative side effects, making them common abiotic stressors. One of the most significant nutritional crops in the world is the wheat plant. Conditions of herbicide stress have a negative impact on the plant’s phonological phases and metabolic pathways. Plants primarily make an effort to adjust to the environment and develop oxidative homeostasis, which supports stress tolerance. Methods: When controlling broadleaf weeds that emerge after cereal crop plants have been planted, bromoxynil is frequently used as a selective-contact herbicide. This study looked at the effects of the cyanobacteria Arthrospira platensis and Nostoc muscorum aqueous extracts, tryptophan, and bromoxynil (Bh) alone or in combination on wheat plant growth parameters. Both tryptophan and cyanobacterial extract were used as chemical and natural safeners against Bh application. The antioxidant activity and transcriptome studies using qRT-PCR were assayed after 24, 48, 72, 96 h, and 15 days from Bh application in the vegetation stage of wheat plants (55 days old). Results: In comparison with plants treated with Bh, wheat plants treated with cyanobacteria and tryptophan showed improvements in all growth parameters. Following application of Bh, wheat plants showed reduced glutathione content, as well as reduced antioxidant enzyme activities of superoxide dismutase, catalase, glutathione peroxidase, and glutathione-s-transferase. The combination of different treatments and Bh caused alleviation of the harmful effect induced by Bh on the measured parameters. Additionally, the expression of glutathione synthase and glutathione peroxidase, in addition to those of three genes (Zeta, Tau, and Lambda) of the GST gene family, was significantly upregulated when using Bh alone or in combination with different treatments, particularly after 24 h of treatment. Conclusion: The current study suggests using cyanobacterial extracts, particularly the A. platensis extract, for the development of an antioxidant defense system against herbicide toxicity, which would improve the metabolic response of developed wheat plants.

Evolution of pathogenicity in obligate fungal pathogens and allied genera.

Obligate fungal pathogens (ascomycetes and basidiomycetes) and oomycetes are known to cause diseases in cereal crop plants. They feed on living cells and most of them have learned to bypass the host immune machinery. This paper discusses some of the factors that are associated with pathogenicity drawing examples from ascomycetes, basidiomycetes and oomycetes, with respect to their manifestation in crop plants. The comparisons have revealed a striking similarity in the three groups suggesting convergent pathways that have arisen from three lineages independently leading to an obligate lifestyle. This review has been written with the intent, that new information on adaptation strategies of biotrophs, modifications in pathogenicity strategies and population dynamics will improve current strategies for breeding with stable resistance.

Source-To-Sink Transport of Sugar and Its Role in Male Reproductive Development.

Sucrose is produced in leaf mesophyll cells via photosynthesis and exported to non-photosynthetic sink tissues through the phloem. The molecular basis of source-to-sink long-distance transport in cereal crop plants is of importance due to its direct influence on grain yield—pollen grains, essential for male fertility, are filled with sugary starch, and rely on long-distance sugar transport from source leaves. Here, we overview sugar partitioning via phloem transport in rice, especially where relevant for male reproductive development. Phloem loading and unloading in source leaves and sink tissues uses a combination of the symplastic, apoplastic, and/or polymer trapping pathways. The symplastic and polymer trapping pathways are passive processes, correlated with source activity and sugar gradients. In contrast, apoplastic phloem loading/unloading involves active processes and several proteins, including SUcrose Transporters (SUTs), Sugars Will Eventually be Exported Transporters (SWEETs), Invertases (INVs), and MonoSaccharide Transporters (MSTs). Numerous transcription factors combine to create a complex network, such as DNA binding with One Finger 11 (DOF11), Carbon Starved Anther (CSA), and CSA2, which regulates sugar metabolism in normal male reproductive development and in response to changes in environmental signals, such as photoperiod.

Quality evaluation of millet (Panicum miliaceum) instant cereal product in Cebu, Philippines

Millet is a collective term referring to several small-grained cereal crop plants belonging to the grass family which are used as human food and is considered an important staple in several countries in the arid and semi-arid tropics. With the increasing appreciation concerning the benefits of millet, there has been an inclination towards their consumption. Literature on the millet production, processing, and introduction of millet in the Philippines has been minimal, even though a few millet species are successfully grown in the Visayas region. This study was conducted to develop an instant cereal product from millet. This includes the milling of millet to powder, cooked, and packed for the desired amount. Five treatments representing five different concentration levels of millet (80%, 65%, 50%, 35%, and 20%) and five different concentration levels of powdered skimmed milk (20%, 35%, 50%, 65%, and 80%). A single factor experiment arranged in a complete randomized design (CRD) was used in the study. The study results showed that significant differences were noted in the sensory attributes in terms of colour, aroma, taste, flavour, mouthfeel, and the overall acceptability of the millet instant cereal product. The treatment with a concentration mixture of 20% millet and 80% powdered skimmed milk (4 g millet and 16 g powdered skimmed milk for a 30 g serving size) was considered the most acceptable. Proximate analysis of the millet instant cereal product showed that it contains 4.53±0.21 moisture, 2.60±0.03 ash, 0.34±0.08 crude fibre, 3.95±0.05 fat, and 8.61±0.11 crude protein. Based on the prevailing market price of millet ($4/kg) and skim milk powder ($3.5/kg), Treatment 5 had the least partial cost with $0.071 per serving size of 30 g. It can be noted that the lesser the amount of millet in the formulation, the better was the acceptability of each sensory attribute as evaluated, and the cheaper it was to produce the millet instant cereal.

Virus-Induced Gene Silencing in Wheat and Related Monocot Species.

Advances made in genome sequencing projects and structural genomics are generating large repertoire of candidate genes in plants associated with specific agronomic traits. Rapid and high-throughput functional genomics approaches are therefore needed to validate the biological function of these genes especially for agronomically important crops beyond the few model plant species. This can be achieved by utilizing available gene knockout or transgenic methodologies, but these can take considerable time and effort particularly in crops with large and complex genomes such as wheat. Therefore, any tool that expedites the validation of gene function is of particular benefit especially in cereal crop plants that are genetically difficult to transform. One such reverse genetics tool is virus-induced gene silencing (VIGS) which relies on the plants' natural antiviral RNA silencing defence mechanism. VIGS is used to downregulate target gene expression in a transient manner which persists long enough to determine its effect on a specific trait. VIGS based on Barley stripe mosaic virus (BSMV) is rapid, powerful, efficient, and relatively inexpensive tool for the analysis of gene function in cereal species. Here we present detailed protocols for BSMV-mediated VIGS for robust gene silencing in bread wheat and related species.

Sorghum-Phosphate Solubilizers Interactions: Crop Nutrition, Biotic Stress Alleviation, and Yield Optimization.

Sweet sorghum [Sorghum bicolor (L.) Moench] is a highly productive, gluten-free cereal crop plant that can be used as an alternative energy resource, human food, and livestock feed or for biofuel-ethanol production. Phosphate fertilization is a common practice to optimize sorghum yield but because of high cost, environmental hazards, and soil fertility reduction, the use of chemical P fertilizer is discouraged. Due to this, the impetus to search for an inexpensive and eco-friendly microbiome as an alternative to chemical P biofertilizer has been increased. Microbial formulations, especially phosphate solubilizing microbiome (PSM) either alone or in synergism with other rhizobacteria, modify the soil nutrient pool and augment the growth, P nutrition, and yield of sorghum. The use of PSM in sorghum disease management reduces the dependence on pesticides employed to control the phytopathogens damage. The role of PSM in the sorghum cultivation system is, however, relatively unresearched. In this manuscript, the diversity and the strategies adopted by PSM to expedite sorghum yield are reviewed, including the nutritional importance of sorghum in human health and the mechanism of P solubilization by PSM. Also, the impact of solo or composite inoculations of biological enhancers (PSM) with nitrogen fixers or arbuscular mycorrhizal fungi is explained. The approaches employed by PSM to control sorghum phytopathogens are highlighted. The simultaneous bio-enhancing and biocontrol activity of the PS microbiome provides better options for the replacement of chemical P fertilizers and pesticide application in sustainable sorghum production practices.

Effect of silver nitrate and growth regulators to enhance anther culture response in wheat (Triticum aestivum L.)

Application of chemical substances as stress pre-treatment factors may positively influence androgenetic responses in cereal and other crops. AgNO3 is an anti-ethylene compounds that played a significant role in combination with other chemicals for anther culture responses in cereal and other crop plants. For this study two local wheat cultivars viz. Kheri and Akbar were considered to evaluate the effect of AgNO3 and to optimize the suitable doses of plant growth regulators, amino acids and sucrose that supplemented in MS medium. Data were recorded on the basis of embryoids induction, regenerated green and albino plants. The results clearly stated that anther culture responses and its major outcomes on regeneration significantly increased with suitable dosages of chemicals. The most noteworthy increases embryo like structures and regenerated green plants accomplished by utilizing the combined effect of AgNO3 (50 mg/l) and as plant growth regulators IAA (1.0 mg/l) + kinetin (0.5 mg/l). Best embryo like structures (79.17%) and green plants (33.33%) were recorded in Kheri. The results clearly stated that reducing albinism and increasing embryos induction and green plants 50–75 mg/l silver nitrate along with optimum doses of IAA and kinetin showed very effective results in wheat.

Genetic response of growth phases for abiotic environmental stress tolerance in cereal crop plants

The yield potential and quality of main cereals crop plants including maize, wheat, rice and barley have improved through breeding and introduction of transgenic crop plants from last three decades. There has been intensive research for the improvement of resistance against biotic and abiotic environmental conditions to safe the potential of cereal crop plants. Among abiotic stresses drought and heat are two most important abiotic factors which caused major loss in yield and quality of crop plants. The heat stress leads towards drought due to loss of water from soil and plant surfaces, therefore drought and heat caused combined adverse effects on plant morphological, physiological and yield traits which leads to reduce crop plant potential. There has been always an interaction among the environmental conditions and crop plants to produce grain and restore productivity. The drought and heat stress caused changes at cellular level, molecular changes and gene expression changes in cereals at various vegetative and reproductive stages/phases of crop growth and development. A large number of genes have indentified in cereals which switch up-regulated and down-regulated during drought and heat stress conditions. However, there is a need to improve resistance in cereals at gene level to maintain potential of yield and quality under abiotic stress conditions like drought, heat, salinity, and cold.

Effect of Trichoderma Spp. as a Bio-control Agent on Cereal Crop Plants

Trichoderma is a Deuteromycetous fungus with hyphae long, creeping, conidiophores erect, philiadic, having conidial heads. Trichoderma species produces a chemical, trichodermin; it is the sesquiteroenoid acting as a bio-control agent on the principal of myco-parasitism, antibiosis and competition to control soil borne plant pathogens. The phytotoxic effect was screened by treating cereal crop seeds with culture filtrate of Trichoderma species, the effect of culture filtrate was measured in terms of seed germination percentage and results were compared with control one. The obtained results shows percentage of germination in treated seeds was more than the control. The culture filtrate of Trichoderma harzianum showed superior effects (95-97%) than that of Trichoderma viridae (90-95%) and Trichoderma virens (86-92%) on the seed germination of selected cereal crop seeds

A CYC/TB1-type TCP transcription factor controls spikelet meristem identity in barley.

Barley possesses a branchless, spike-shaped inflorescence where determinate spikelets attach directly to the main axis, but the developmental mechanism of spikelet identity remains largely unknown. Here we report the functional analysis of the barley gene BRANCHED AND INDETERMINATE SPIKELET 1 (BDI1), which encodes a TCP transcription factor and plays a crucial role in determining barley inflorescence architecture and spikelet development. The bdi1 mutant exhibited indeterminate spikelet meristems that continued to grow and differentiate after producing a floret meristem; some spikelet meristems at the base of the spike formed two fully developed seeds or converted to branched spikelets, producing a branched inflorescence. Map-based cloning analysis showed that this mutant has a deletion of ~600 kb on chromosome 5H containing three putative genes. Expression analysis and virus-induced gene silencing confirmed that the causative gene, BDI1, encodes a CYC/TB1-type TCP transcription factor and is highly conserved in both wild and cultivated barley. Transcriptome and regulatory network analysis demonstrated that BDI1 may integrate regulation of gene transcription cell wall modification and known trehalose-6-phosphate homeostasis to control spikelet development. Together, our findings reveal that BDI1 represents a key regulator of inflorescence architecture and meristem determinacy in cereal crop plants.

Effect of Drought and Salt Stress on Cereal Crop Plants and their Proteomic and Physiological Studies

The photosynthetic potential and underlying internal metabolism of a plant are some of the most commonly affected physiological functions as a direct consequence of stresses due to salt and water resulting in hindering plant growth and productivity. Under the influence of such detrimental stresses, a drastic alteration in a plant's osmotic requirements, hormonal production, shedding of leaves, and closure of stomata, along with a lessening in the diffusion and transportation of CO2 and H2O are commonly seen. This review unfolds with a description of the basic methodology involved in the proteomic analysis of various proteins involved in stress response along with a brief idea on identifying and obtaining a genomic sequence for proteomic studies. It then dives deep into understanding the impact of abiotic stresses such as salinity, drought and high temperatures on cereal crops such as rice and sorghum as well as the internal dynamics of tolerance mechanism unfolding during stresses have also been described. Extensive literature describing the proteomic and physiological responses to primary and secondary effects of salt stress in cereal crops emphasizing on ROS production and apoptosis, the role of osmolytes as ROS scavengers during osmotic stress and vacuolar antiporters in ionic stress along with the responses during drought stress such as the accumulation of LEA proteins and ABA-based signaling has been reviewed and critically discussed. The study also sheds light on some experimental proteomic studies conducted on the seedlings, root tissues, and shoots of rice cultivars.

Less Is More: Lower Sowing Rate of Irrigated Tef (Eragrostis tef) Alters Plant Morphology and Reduces Lodging

Tef (Eragrostis tef (Zucc.) Trotter) is a panicle-bearing cereal crop plant, originating from and grown mainly in Ethiopia. Tef yields highly nutritious gluten-free grain as well as high-quality forage, therefore, interest is rising regarding tef cultivation for grain and forage outside Ethiopia. Lodging is a major factor limiting tef quality and yield, with losses estimated at 30%–35% and presumably higher under mechanical harvest. Studies in other cereal crops suggested that lowering plant density would lead to sturdier plants less prone to lodging. In this work, we reported on the effects of sowing rate on lodging, lodging-related traits, and productivity of tef under irrigated conditions. Four tef genotypes were grown under irrigation across two years at three sowing rates: low (3 kg/ha), medium (6 kg/ha), and high (common, 9 kg/ha). Grain yield and biomass did not differ significantly among sowing rates. The visually assessed lodging index (LI) increased as the season progressed, with the lowest values recorded under low sowing density. A significant difference in LI values among the tested genotypes suggested potential for crop improvement. Aerial RGB images of the field taken by an unmanned aerial vehicle twice during the second season produced a high-resolution crop surface model, which was used to assess lodging. Aerial-based LI values were significantly correlated with the ground-based ones and exhibited better capacity to identify minor differences in lodging. Among the morphological traits assessed, crown diameter, crown root number, and crown root diameter were significantly affected by sowing rate and genotype and were correlated with LI values. In summary, this study demonstrated for the first time the feasibility of tef production under irrigated Mediterranean conditions and the potential of a reduced sowing rate as a remedy for lodging.

Plant Transformation Techniques: Agrobacterium- and Microparticle-Mediated Gene Transfer in Cereal Plants.

Biotechnological methods for targeted gene transfers into plants are key for successful breeding in the twenty-first century and thus essential for the survival of humanity. Two decades ago, genetic transformation of crop plants was not routine, and it was all but impossible with important cereals such as barley and wheat. The recent focus on crop plant genomics-yet based on the Arabidopsis toolbox-boosted the research for more efficient plant transformation protocols, thereby considerably widened the number of genetically tractable crops. Moreover, modern genome editing methods such as the CRISPR/Cas technique are game changers in plant breeding, though heavily dependent on technical optimization of plant transformation. Basically, there are two successful ways of introducing DNA into plant cells: one is making use of a living DNA vector, namely, microbes such as the soil bacterium Agrobacterium tumefaciens that infects plants and naturally transfers and subsequently integrates DNA into the plant genome. The other method uses a direct physical transfer of DNA by means of microinjection, microprojectile bombardment, or polymers such as polyethylene glycol. Both ways subsequently require sophisticated strategies for selecting and multiplying the transformed cells under tissue culture conditions to develop into a fully functional plant with the new desirable characteristics. Here we discuss practical and theoretical aspects of cereal crop plant transformation by Agrobacterium-mediated transformation and microparticle bombardment. Using immature embryos as explants, the efficiency of cereal transformation is compelling, reaching today up to 80% transformation efficiency.

The Effect of Different Fertilizer on Aphids Populations

Hordeum vulgare is one of the most important cereal crop plants and severe attacked by aphid. Present study was designed to evaluate the effect of different fertilizers and their combination on aphid infestation in barley. Three different fertilizer i. e. urea, DAP, and urea+DAP were applied to three different barley fields after 25 days of germinations. Data was recorded after every 10 days. Results showed that lowest pest population was recorded in urea+DAP field. DOI : 10.7176/ALST/77-01 Publication date: January 31 st 2020

Analysis of Epigenetic Modifications During Vegetative and Reproductive Development in Cereals Using Chromatin Immunoprecipitation (ChIP).

The study of heritable genetic changes that do not implicate alterations in the DNA sequence-epigenetics-represents one of the most prolific and expanding fields in plant biology during the last two decades. With a focus on DNA methylation and histone modifications, recent advances also reported the identification of epigenetic regulatory mechanisms that control reproductive development in cereal crop plants. One of the most powerful methods to selectively study interactions between epigenetic factors or specific proteins bound to genomic DNA regions is called chromatin immunoprecipitation (ChIP). ChIP can be widely used to determine the presence of particular histones with posttranslational modifications at specific genomic regions or whether and where specific DNA-binding proteins including transcription factors interact with candidate target genes. ChIP is also an exciting tool to study and compare chromatin states under normal and stress conditions. Here, we present a detailed step-by-step ChIP assay to investigate epigenetic chromatin marks during vegetative and reproductive development in cereals. However, the method described here can be used for all plant tissues and plant species.

Fluorescent reporter lines for auxin and cytokinin signalling in barley (Hordeum vulgare).

The phytohormones auxin and cytokinin control development and maintenance of plant meristems and stem cell systems. Fluorescent protein reporter lines that monitor phytohormone controlled gene expression programmes have been widely used to study development and differentiation in the model species Arabidopsis, but equivalent tools are still missing for the majority of crop species. Barley (Hordeum vulgare) is the fourth most abundant cereal crop plant, but knowledge on these important phytohormones in regard to the barley root and shoot stem cell niches is still negligible. We have now analysed the role of auxin and cytokinin in barley root meristem development, and present fluorescent protein reporter lines that allow to dissect auxin and cytokinin signalling outputs in vivo. We found that application of either auxin or cytokinin to barley seedlings negatively impacts root meristem growth. We further established a barley cytokinin reporter, TCSnew, which revealed significant cytokinin signalling in the stele cells proximal to the QC, and in the differentiated root cap cells. Application of exogenous cytokinin activated signalling in the root stem cell niche. Commonly employed auxin reporters DR5 or DR5v2 failed to respond to auxin in barley. However, analysis of putative auxin signalling targets barley PLETHORA1 (HvPLT1) is expressed in a similar pattern as its orthologue AtPLT1 from Arabidopsis, i.e. in the QC and the surrounding cells. Furthermore, the PINFORMED1 (HvPIN1) auxin efflux carrier was found to be expressed in root and shoot meristems, where it polarly localized to the plasma membrane. HvPIN1 expression is negatively regulated by cytokinin and its intracellular localisation is sensitive to brefeldinA (BFA). With this study, we provide the first fluorescent reporter lines as a tool to study auxin and cytokinin signalling and response pathways in barley.