Dicotyledonous Crops Research Articles

Metproxybicyclone, a Novel Carbocyclic Aryl-dione Acetyl-CoA Carboxylase-Inhibiting Herbicide for the Management of Sensitive and Resistant Grass Weeds.

Postemergence control of grass weeds has become problematic due to the evolution of resistance to 5-enolpyruvylshikimate-3-phosphate synthase, acetyl-CoA carboxylase (ACCase), and acetolactate synthase-inhibiting herbicides. Herein we describe the invention and synthesis journey toward metproxybicyclone, the first commercial carbocyclic aryl-dione ACCase-inhibiting herbicide for the cost-effective management of grass weeds in dicotyledonous crops and in preplant burndown applications. Glasshouse and field experiments have shown that metproxybicyclone is safe for use on soybean, cotton, and sugar beet, among other crops. It is effective on a variety of key grass weeds including Eleusine indica, Digitaria insularis, Sorghum halepense, and Echinochloa crus-galli. Importantly, metproxybicyclone was more efficacious at killing resistant grass weed populations than current ACCase herbicides. Metproxybicyclone controlled the main ACCase target-site and nontarget site resistant mechanisms in characterized Lolium multiflorum and E. indica populations under glasshouse conditions. Excellent control of a broad resistance-causing D2078G target-site mutant E. indica population was also observed under field conditions.

Heritable gene editing in tomato through viral delivery of isopentenyl transferase and single-guide RNAs to latent axillary meristematic cells

Realizing the full potential of genome editing for crop improvement has been slow due to inefficient methods for reagent delivery and the reliance on tissue culture for creating gene-edited plants. RNA viral vectors offer an alternative approach for delivering gene engineering reagents and bypassing the tissue culture requirement. Viruses, however, are often excluded from the shoot apical meristem, making virus-mediated gene editing inefficient in some species. Here, we developed effective approaches for generating gene-edited shoots in Cas9-expressing transgenic tomato plants using RNA virus-mediated delivery of single-guide RNAs (sgRNAs). RNA viral vectors expressing sgRNAs were either delivered to leaves or sites near axillary meristems. Trimming of the apical and axillary meristems induced new shoots to form from edited somatic cells. To further encourage the induction of shoots, we used RNA viral vectors to deliver sgRNAs along with the cytokinin biosynthesis gene, isopentenyl transferase. Abundant, phenotypically normal, gene-edited shoots were induced per infected plant with single and multiplexed gene edits fixed in the germline. The use of viruses to deliver both gene editing reagents and developmental regulators overcomes the bottleneck in applying virus-induced gene editing to dicotyledonous crops such as tomato and reduces the dependency on tissue culture.

Analysis of Twenty Years of Suction Trap Data on the Flight Activity of Myzus persicae and Brevicoryne brassicae, Two Main Vectors of Oilseed Rape Infection Viruses

Myzus persicae and Brevicoryne brassicae are the main aphid pests and vectors of viruses that attack many crops, including oilseed rape, the most commonly grown dicotyledonous crop in the Czech Republic. In this study, we analysed the flight activity of both aphids from five suction traps over 20 years (2004–2023). We focussed on (i) the influence of the ban on seed dressing with neonicotinoids on aphid catches, (ii) the influence of the average temperature on flight activity, and (iii) the number of males/females caught in the suction traps. We compared the data on aphid flight activity at the coldest and warmest sites and found that migration starts about 10 days earlier at the warmest site than at the coldest site and that aphid populations are more numerous here. The number of catches in suction traps was observed for both aphids after the ban on neonicotinoids was significantly increased. For M. persicae, it was about 9 times higher, while for B. brassicae, it was about 1.3 times higher. In addition, we observed a significant decrease in the number of males in M. persicae with a simultaneous increase in the number of females (in autumn), which could be an indication of the formation of anholocyclic populations. Overall, our results showed a significantly high abundance of both aphid species depending on the observed locations, which seems to be related to the ban of neonicotinoids. Therefore, an effective alternative is needed to improve the control of aphid vectors that can ensure the stability of crops against aphid-transmitted virus diseases.

Greater mesophyll conductance and leaf photosynthesis in the field through modified cell wall porosity and thickness via AtCGR3 expression in tobacco.

Mesophyll conductance (gm) describes the ease with which CO2 passes from the sub-stomatal cavities of the leaf to the primary carboxylase of photosynthesis, Rubisco. Increasing gm is suggested as a means to engineer increases in photosynthesis by increasing [CO2] at Rubisco, inhibiting oxygenation and accelerating carboxylation. Here, tobacco was transgenically up-regulated with Arabidopsis Cotton Golgi-related 3 (CGR3), a gene controlling methylesterification of pectin, as a strategy to increase CO2 diffusion across the cell wall and thereby increase gm. Across three independent events in tobacco strongly expressing AtCGR3, mesophyll cell wall thickness was decreased by 7%-13%, wall porosity increased by 75% and gm measured by carbon isotope discrimination increased by 28%. Importantly, field-grown plants showed an average 8% increase in leaf photosynthetic CO2 uptake. Up-regulating CGR3 provides a new strategy for increasing gm in dicotyledonous crops, leading to higher CO2 assimilation and a potential means to sustainable crop yield improvement.

Mapping weed infestation in maize fields using Sentinel-2 data

Weed management in maize farms is a time-specific activity and requires timely detection of weed infestations. The challenge to early detection of weeds is that many dicotyledonous crops and broad-leaved weeds often display similar reflectance profile in the early growth stage and requires hyperspectral data to detect them. However, the advent of Sentinel-2 sensor series, with enhanced spectral configuration featuring red-edge bands that are known for species-level discrimination of plants, presents an affordable opportunity to detect weeds using multispectral data. The present study explores the question of whether Sentinel-2 sensor with its advanced spectral configuration can differentiate weeds from maize (Zea mays) in the early growth stages of maize. The study recorded 165 GPS points of weeds, maize, and mixed class in six maize farms during the early stages of maize growth. These GPS points were overlaid on Sentinel-2 images acquired within two days of field data gathering to guide the collection of spectral signatures of the maize, mixed, and weed classes. Spectral signatures were divided into training (70%) and validation (30%) data in a Random Forest (RF) model with S-2 spectral bands and vegetation indices as predictor variables. Spectral signatures were firstly tested for spectral separability between classes using ANOVA. The results of spectral analysis showed that the weed class had higher interclass variability from the maize and mixed class particularly in the red-edge and NIR regions of Sentinel-2. The classification matrix consistently showed that weeds were detected with high user and producers’ accuracy of 95%. These results indicate the utility of the enhanced spectral configuration of Sentinel-2 data in the early detection of weeds in maize farms.

ИЗУЧЕНИЕ ВЛИЯНИЯ ЭНДОФИТНЫХ БАКТЕРИЙ РОДА BACILLUS НА РОСТ И СТРЕССОУСТОЙЧОВОСТЬ ПРОРОСТКОВ ЯРОВОЙ ПШЕНИЦЫ И СОИ

The studies were carried out to assess the indicators of seed germination, root length, level of lipid peroxidation, content of photosynthetic pigments and free proline in monocotyledonous and dicotyledonous crops when seeds were treated with strains of endophytic bacteria of the genus Bacillus. The scheme of vegetation experiments included modeling of 30% drought on sand and pre-sowing treatment of seeds of spring wheat variety Yoldyz and soybean variety Sultana with endophytic bacteria: Bacillus subtilis KS-55 AU, Bacillus cereus KS-56 AU, Bacillus pumilus KS-57 AU, Bacillus megaterium KS- 58 AU, Bacillus cereus KS-59 AU, Bacillus megaterium KS-60 AU and Bacillus pumilus KS-61 AU. Bacteria better stimulated root growth when using a titer of 1×106 cells in 1 ml of the drug (the increase was 0.6 cm on soybean with Bacillus subtilis KS-55 AU and Bacillus megaterium KS-60 AU and 0.4 cm on wheat with Bacillus cereus KS -56 AU, Bacillus cereus KS-59 AU and Bacillus pumilus KS-61 AU). In wheat, the Bacillus subtilis KS-55 AU strain stood out, treatment with which contributed to an increase in germination by 30%, a decrease in the level of lipid peroxidation by 46%, an increase in the amount of free proline by 148% and photosynthetic pigments by 6%, relative to the control variant. On soybean plants, the strain Bacillus subtilis KS-55 AU contributed to an increase in germination by 40%, Bacillus cereus KS-59 AU contributed to a decrease in the level of lipid peroxidation by 47% and the accumulation of proline by 73%, and Bacillus pumilus KS-61 AU increased the amount of total chlorophyll by 141%, relative to the control variant. Thus, we can conclude that the above strains of endophytic bacteria improve the growth and development of spring wheat and soybean seedlings, and also serve as inducers of crop resistance to soil drought.

Effects of potassium fertilizer rates on growth, tuber yield and quality of sweet potato (Ipomea batatas L) in Ogbomoso, Southwest Nigeria

Sweet potato (Ipomoea batatas L) is an important dicotyledonous tuberous staple crop of the Convolvulaceae family. It is valued for its tubers which are either boiled, fried, baked or roasted for human consumption or boiled and fed to livestock as a source of energy. However, the cultivation of sweet potato is constrained by low soil fertility, particularly inadequate potassium, which plays a pivotal role in the growth and tuber development of sweet potato. Therefore, the effects of potassium fertilizer rates on the growth, tuber yield and quality of sweet potato were determined at the Teaching and Research Farm, Ladoke Akintola University of Technology, Ogbomoso during 2022 major cropping season. The treatments were; 0 (control), 60, 90, 120, 150 and 180 kg K2O/ha laid out in randomized complete block design replicated three times. Data collected on length of primary vines, number of leaves, fresh shoot biomass, number of tubers, fresh tuber yield and nutritional contents of the tubers were subjected to analysis of variance and treatment means separated with least significance difference (LSD) at 5% probability level. The application of K fertilizer had significant influence on the performance of sweet potato. At 14 weeks after planting (WAP), plants treated with 180 kg K2O/ha produced the longest mean vine length (p = 0.043, 184.93 cm), highest number of leaves (p = 0.003, 217), highest fresh shoot biomass (p = 0.015, 11.83 t/ha), number of tubers (p = 0.037, 68) and fresh tuber yield (p = 0.0004, 22 t/ha). In contrast, plants that received no fertilizer, had the shortest vine length (133.67 cm), the least fresh shoot biomass (7.1 t/ha) and tuber yield (12.7 t/ha). The least number of leaves (136) was observed with the application of 60 kg K2O/ha while 90 kg K2O/ha produced the least number of tubers (46). The potassium content of sweet potato tuber was significantly influenced by K fertilizer rates, whereas the phosphorus content was unaffected. The highest contents of phosphorus (p = 0.967, 0.10%) and potassium (p = 0.038, 1.26%) were recorded in tubers that received 150 kg K2O/ha and 180 kg K2O/ha, respectively. The carotenoid, carbohydrate, and protein contents of sweet potato tuber decreased as the potassium rates increased. Conversely, the crude fiber content increased (p = 0.044) as the potassium rate increased. In conclusion, application of 180 kg K2O/ha improved the performance of sweet potato better than the other rates in the study area. However, it seems that the maximum yield potential of sweet potato in the study area had not been attained. Therefore, further research with higher than 180 kg K2O/ha may be required to identify the optimal level for cultivating sweet potatoes.

A cAMP phosphodiesterase is essential for sclerotia formation and virulence in Sclerotinia sclerotiorum.

Sclerotinia sclerotiorum is a plant pathogenic fungus that causes white mold or stem rot diseases. It affects mostly dicotyledonous crops, resulting in significant economic losses worldwide. Sclerotia formation is a special feature of S. sclerotiorum, allowing its survival in soil for extended periods and facilitates the spread of the pathogen. However, the detailed molecular mechanisms of how sclerotia are formed and how virulence is achieved in S. sclerotiorum are not fully understood. Here, we report the identification of a mutant that cannot form sclerotia using a forward genetics approach. Next-generation sequencing of the mutant's whole genome revealed candidate genes. Through knockout experiments, the causal gene was found to encode a cAMP phosphodiesterase (SsPDE2). From mutant phenotypic examinations, we found that SsPDE2 plays essential roles not only in sclerotia formation, but also in the regulation of oxalic acid accumulation, infection cushion functionality and virulence. Downregulation of SsSMK1 transcripts in Sspde2 mutants revealed that these morphological defects are likely caused by cAMP-dependent inhibition of MAPK signaling. Moreover, when we introduced HIGS construct targeting SsPDE2 in Nicotiana benthamiana, largely compromised virulence was observed against S. sclerotiorum. Taken together, SsPDE2 is indispensable for key biological processes of S. sclerotiorum and can potentially serve as a HIGS target to control stem rot in the field.

Host Resistance to Parasitic Plants—Current Knowledge and Future Perspectives

Parasitic flowering plants represent a diverse group of angiosperms, ranging from exotic species with limited distribution to prominent weeds, causing significant yield losses in agricultural crops. The major damage caused by them is related to the extraction of water and nutrients from the host, thus decreasing vegetative growth, flowering, and seed production. Members of the root parasites of the Orobanchaceae family and stem parasites of the genus Cuscuta are among the most aggressive and damaging weeds, affecting both monocotyledonous and dicotyledonous crops worldwide. Their control and eradication are hampered by the extreme seed longevity and persistence in soil, as well as their taxonomic position, which makes it difficult to apply selective herbicides not damaging to the hosts. The selection of resistant cultivars is among the most promising approaches to deal with this matter, although still not widely employed due to limited knowledge of the molecular mechanisms of host resistance and inheritance. The current review aims to summarize the available information on host resistance with a focus on agriculturally important parasitic plants and to outline the future perspectives of resistant crop cultivar selection to battle the global threat of parasitic plants.

Regulation of capsule spine formation in castor.

Castor (Ricinus communis L.) is a dicotyledonous oilseed crop that can have either spineless or spiny capsules. Spines are protuberant structures that differ from thorns or prickles. The developmental regulatory mechanisms governing spine formation in castor or other plants have remained largely unknown. Herein, using map-based cloning in 2 independent F2 populations, F2-LYY5/DL01 and F2-LYY9/DL01, we identified the RcMYB106 (myb domain protein 106) transcription factor as a key regulator of capsule spine development in castor. Haplotype analyses demonstrated that either a 4,353-bp deletion in the promoter or a single nucleotide polymorphism leading to a premature stop codon in the RcMYB106 gene could cause the spineless capsule phenotype in castor. Results of our experiments indicated that RcMYB106 might target the downstream gene RcWIN1 (WAX INDUCER1), which encodes an ethylene response factor known to be involved in trichome formation in Arabidopsis (Arabidopsis thaliana) to control capsule spine development in castor. This hypothesis, however, remains to be further tested. Nevertheless, our study reveals a potential molecular regulatory mechanism underlying the spine capsule trait in a nonmodel plant species.

Comparative transcriptome and genome analysis unravels the response of Tatary buckwheat root to nitrogen deficiency

Tartary buckwheat (Fagopyrum tataricum Garetn.), a dicotyledonous herbaceous crop, has good adaptation to low nitrogen (LN) condition. The plasticity of roots drives the adaption of Tartary buckwheat under LN, but the detailed mechanism behind the response of TB roots to LN remains unclear. In this study, the molecular mechanism of two Tartary buckwheat genotypes' roots with contrasting sensitivity in response to LN was investigated by integrating physiological, transcriptome and whole-genome re-sequencing analysis. LN improved primary and lateral root growth of LN-sensitive genotype, whereas the roots of LN-insensitive genotype showed no response to LN. 2, 661 LN-responsive differentially expressed genes (DEGs) were identified by transcriptome analysis. Of these genes, 17 N transport and assimilation-related and 29 hormone biosynthesis and signaling genes showed response to LN, and they may play important role in Tartary buckwheat root development under LN. The flavonoid biosynthetic genes’ expression was improved by LN, and their transcriptional regulations mediated by MYB and bHLH were analyzed. 78 transcription factors, 124 small secreted peptides and 38 receptor-like protein kinases encoding genes involved in LN response. 438 genes were differentially expressed between LN-sensitive and LN-insensitive genotypes by comparing their transcriptome, including 176 LN-responsive DEGs. Furthermore, nine key LN-responsive genes with sequence variation were identified, including FtNRT2.4, FtNPF2.6 and FtMYB1R1. This paper provided useful information on the response and adaptation of Tartary buckwheat root to LN, and the candidate genes for breeding Tartary buckwheat with high N use efficiency were identified.

Standardization of protocol for in vitro tuberization in potato (Solanum tuberosum) cultivar Kufri Sindhuri

Potato (Solanum tuberosum L.) is an economically important dicotyledonous and tuber crop which is ranked as the fourth most cultivated food crop after wheat, rice and maize. Asexual propagation of potato is done through tubers which are prone to large number of fungal and viral diseases. Microtubers produced through tissue culture serve as an essential component for production of disease-free quality potato seed. The present study was carried out during 2018 and 2019 at School of Biotechnology, Sher-e-Kashmir University of Agriculture Science and Technology of Jammu, Jammu to standardize in vitro microtuber production protocol in potato variety Kufri Sindhuri using different explants. Nodal segments were the most suitable explants for culture establishment which resulted in maximum survival with least contamination and mortality. Murashige and Skoog medium supplemented with BAP (1.5 mg/litre) and NAA (0.1 mg/litre) resulted in 100% shoot regeneration with 3.75 shoots per explant. Vigorous shoot proliferation was achieved by fortification of calcium pentothenate (2 mg/litre) and gibberellic acid (0.25 mg/litre) in establishment medium. Pre-tuberization was done by incubating cultures for 28 days in liquid multiplication medium supplemented with NAA (0.5 mg/litre). Maximum microtubers (24) per culture flask were obtained in 10 days when tuberization medium was fortified with 80 g/litre of sucrose while maximum diameter of 0.9 cm was recorded in the presence of growth retardant chlorocholine chloride (500 mg/litre). Complete darkness was an essential factor for microtuber induction. The harvested microtubers (G0) were stored at 4°C after treating them with fungicides.

Waitea circinata var. zeae - prouzrokovač truleži korena kupusa i uljane repice

Waitea circinata var. zeae (anamorf Rhizoctonia zeae) is an important pathogen of mainly monocotyledonous plants characterized by its soil-borne nature and capability for the long-term preservation. The host range of W. circinata var. zeae recently expanded to several dicotyledonous crops. The latest research conducted in Serbia revealed this pathogen as the causal agent of root and root neck rot, as well as plant decay of cabbage and oilseed at the localities of Futog and Rimski Šančevi. In this paper the available data on the distribution, preservation, dissemination pattern and control of W. circinata var. zeae, as well as research in Serbia are discussed.

Competitiveness and Policy Analysis of Potato Production in Different Agro-ecological Zones of Northern Areas: Implications for Food Security and Poverty Alleviation

Potato (L. Solanum tuberosum) belongs to Solanaceae family. It is the most important dicotyledonous tuber crop and possesses major socio-economic importance worldwide. It is the fourth most cultivated food crop after wheat, rice and maize in world. Potato is a good and cheaper source of carbohydrates, vitamins, minerals and proteins and also provides most of the trace elements, which can meet the energy requirement of the people living in the developing countries like Pakistan [Rahman (1986)]. About 325 million metric ton of potato is produced annually throughout the world [World Book (2001)]. This crop is financially more remunerative than cereals from food security and can be recommended as a partial replacement of cereals.

In vivo maternal haploid induction based on genome editing of DMP in Brassica oleracea.

In vivo maternal haploid induction based on genome editing of DMP in Brassica oleracea.

The field phenotyping platform's next darling: Dicotyledons.

The genetic information and functional properties of plants have been further identified with the completion of the whole-genome sequencing of numerous crop species and the rapid development of high-throughput phenotyping technologies, laying a suitable foundation for advanced precision agriculture and enhanced genetic gains. Collecting phenotypic data from dicotyledonous crops in the field has been identified as a key factor in the collection of large-scale phenotypic data of crops. On the one hand, dicotyledonous plants account for 4/5 of all angiosperm species and play a critical role in agriculture. However, their morphology is complex, and an abundance of dicot phenotypic information is available, which is critical for the analysis of high-throughput phenotypic data in the field. As a result, the focus of this paper is on the major advancements in ground-based, air-based, and space-based field phenotyping platforms over the last few decades and the research progress in the high-throughput phenotyping of dicotyledonous field crop plants in terms of morphological indicators, physiological and biochemical indicators, biotic/abiotic stress indicators, and yield indicators. Finally, the future development of dicots in the field is explored from the perspectives of identifying new unified phenotypic criteria, developing a high-performance infrastructure platform, creating a phenotypic big data knowledge map, and merging the data with those of multiomic techniques.

Herbicide residues in Australian grain cropping soils at sowing and their relevance to crop growth

Herbicides are used extensively in Australian grain cropping systems. Despite occasional observations of herbicide-induced phytotoxicity, there is little information on the persistence and carryover of multiple herbicide classes in cropping soils and the risk to subsequent crops. Two soil surveys were conducted, in 2015 (n = 40) and 2016 (n = 42), across different Australian grain cropping fields prior to sowing of winter crops, and soil samples analysed for herbicide residues (16 analytes in 2015 and 22 analytes in 2016). Samples in 2015 were taken at two depths (0–10 cm and 10-30 cm), whilst samples in 2016 were taken in topsoil (0–10 cm) only, but from two discrete locations in each field. Our research in both years found at least one herbicide (or herbicide metabolite) residue at all sites, with a median of 6 analytes detected in 2015 and 7 analytes detected in 2016. The most frequently detected residues were glyphosate and its primary breakdown product aminomethylphosphonic acid (AMPA), in 87 and 100%, respectively, of topsoil (0–10 cm) samples in 2015, and 67 and 93% of samples in 2016. The median concentration of glyphosate in 2015 was 0.12 mg kg−1, while AMPA was 0.41 mg kg−1. In 2016, median concentrations of glyphosate and AMPA were 0.22 mg kg−1 and 0.31 mg kg−1. Residues of 2,4-dichlorophenoxyacetic acid, trifluralin and diflufenican were also detected in >40% of topsoil samples in both seasons, but with median concentrations of <0.05 mg kg−1. A literature review found limited availability of phytotoxicity thresholds for major grain crops exposed to soilborne herbicide residues. A risk assessment using available thresholds suggested that although up to 29% of fields contained trifluralin residues that could constrain cereal crop growth, and 24% of fields contained residues of phenoxy or sulfonylureas that could affect dicotyledonous crops, the majority of these fields when planted with tolerant crops would be unlikely to be affected by herbicide residues. More work is required to ascertain the spatial distribution, bioavailability and phytotoxicity of residues and residue mixtures to enable a more accurate agronomic risk assessment.

Sources of genomic diversity in the self-fertile plant pathogen, Sclerotinia sclerotiorum, and consequences for resistance breeding.

The ascomycete, Sclerotinia sclerotiorum, has a broad host range and causes yield loss in dicotyledonous crops world wide. Genomic diversity was determined in a population of 127 isolates obtained from individual canola (Brassica napus) fields in western Canada. Genotyping with 39 simple sequence repeat (SSR) markers revealed each isolate was a unique haplotype. Analysis of molecular variance showed 97% was due to isolate and 3% due to geographical location. Testing of mycelium compatibility among 133 isolates identified clones of mutually compatible isolates with 86–95% similar SSR haplotype, whereas incompatible isolates were highly diverse. In the Province of Manitoba, 61% of isolates were compatible forming clones and stings of pairwise compatible isolates not described before. In contrast, only 35% of isolates were compatible in Alberta without forming clones and strings, while 39% were compatible in Saskatchewan with a single clone, but no strings. These difference can be explained by wetter growing seasons and more susceptible crop species in Manitoba favouring frequent mycelium interaction and more life cycles over time, which might also explain similar differences observed in other geographical areas and host crops. Analysis of linkage disequilibrium rejected random recombination, consistent with a self-fertile fungus, restricted outcrossing due to mycelium incompatibility, and only a single annual opportunity for genomic recombination during meiosis in the ascospore stage between non-sister chromatids in the rare event nuclei from different isolates come together. More probable sources of genomic diversity is slippage during DNA replication and point mutation affecting single nucleotides that accumulate and likely increase mycelium incompatibility in a population over time. A phylogenetic tree based on SSR haplotype grouped isolates into 17 sub-populations. Aggressiveness was tested by inoculating one isolate from each sub-population onto B. napus lines with quantitative resistance. Analysis of variance was significant for isolate, line, and isolate by line interaction. These isolates represent the genomic and pathogenic diversity in western Canada, and are suitable for resistance screening in canola breeding programs.

Genetic diversity and evolutionary analyses of potyviruses infecting narcissus in Iran.

Potyviruses are among the most important pathogens of dicotyledonous and monocotyledonous ornamentals and crop plants. In this study, leaf samples were collected from symptomatic narcissus plants and weeds in Fars and Tehran provinces of Iran. Enzyme-linked immunosorbent assay using broad-spectrum potyvirus antibodies gave a positive reaction with 38 out of 61 narcissus samples tested (62.3%); the results were confirmed by reverse-transcription polymerase chain reaction using universal NIb primers, and for thirty samples, by sequencing and phylogenetic studies. The results suggested the infection of almost all positive samples with narcissus yellow stripe virus (NYSV); only one sample seemed to be infected with narcissus late season yellows virus (NLSYV). The 3'-end of the genome of the NLSYV isolate and six NYSV isolates, encompassing the complete coat protein gene, was amplified and sequenced using species-specific and universal potyvirus primers. Sequence analysis indicated the presence of NLSYV and NYSV, not previously identified from Western Asia. No evidence of recombination was found in Iranian isolates. Based on phylogenetic analyses, isolates of NLSYV and NYSV clustered into five and three phylogroups, respectively, where all the Iranian isolates fell into distinct subpopulations in groups NLSYV-I and NYSV-II. Multiple sequence alignments showed some phylogroup-specific amino acid substitutions for both viruses. Phylogroup IV and II populations had higher nucleotide diversities as compared with other populations of NLSYV and NYSV, respectively. Our findings revealed the presence of negative selection in the populations of both viruses. Almost no statistically significant gene flow was found between populations of these viruses.Supplementary informationThe online version contains supplementary material available at 10.1007/s42161-021-00985-0.

Zinc deficiency responses: bridging the gap between Arabidopsis and dicotyledonous crops.

Zinc (Zn) deficiency is a widespread phenomenon in agricultural soils worldwide and has a major impact on crop yield and quality, and hence on human nutrition and health. Although dicotyledonous crops represent >30% of human plant-based nutrition, relatively few efforts have been dedicated to the investigation of Zn deficiency response mechanisms in dicotyledonous, in contrast to monocotyledonous crops, such as rice or barley. Here, we describe the Zn requirement and impact of Zn deficiency in several economically important dicotyledonous crops, Phaseolus vulgaris, Glycine max, Brassica oleracea, and Solanum lycopersicum. We briefly review our current knowledge of the Zn deficiency response in Arabidopsis and outline how this knowledge is translated in dicotyledonous crops. We highlight commonalities and differences between dicotyledonous species (and with monocotyledonous species) regarding the function and regulation of Zn transporters and chelators, as well as the Zn-sensing mechanisms and the role of hormones in the Zn deficiency response. Moreover, we show how the Zn homeostatic network intimately interacts with other nutrients, such as iron or phosphate. Finally, we outline how variation in Zn deficiency tolerance and Zn use efficiency among cultivars of dicotyledonous species can be leveraged for the design of Zn biofortification strategies.