Search

A better understanding of the genetic and ecological factors underlying successful invasions is critical to mitigate the negative impacts of invasive species. Here, we study the invasion history of Helianthus annuus populations from Argentina, with particular emphasis on the role of post‐introduction admixture with cultivated sunflower (also H. annuus) and climate adaptation driven by large haploblocks. We conducted genotyping‐by‐sequencing of samples of wild populations as well as Argentinian cultivars and compared them with wild (including related annual Helianthus species) and cultivated samples from the native range. We also characterised samples for 11 known haploblocks associated with environmental variation in native populations to test whether haploblocks contributed to invasion success. Population genomics analyses supported two independent geographic sources for Argentinian populations, the central United States and Texas, but no significant contribution of related annual Helianthus species. We found pervasive admixture with cultivated sunflower, likely as result of post‐introduction hybridization. Genomic scans between invasive populations and their native sources identified multiple genomic regions of divergence, possibly indicative of selection, in the invaded range. These regions significantly overlapped between the two native‐invasive comparisons and showed disproportionally high crop ancestry, suggesting that crop alleles contributed to invasion success. We did not find evidence of climate adaptation mediated by haploblocks, yet outliers of genome scans were enriched in haploblock regions and, for at least two haploblocks, the cultivar haplotype was favoured in Argentina. Our results show that admixture with cultivated sunflower played a major role in the establishment and spread of H. annuus populations in Argentina. [ABSTRACT FROM AUTHOR]

• Helianthus annuus L. is a significant oilseed plant with economic importance. • Secondary metabolites in plants have high potential to produce new drugs and bioactive compounds. • Compounds with anticancer properties such as taxadiene-5α-hydroxylase, parthenolide synthase, vinorine synthase etc. have been identified in H. annuus. • There are gene clusters categorized as polyketide, saccharide, saccharide-terpene, alkaloid, putative, and terpene types in H. annuus. Plant secondary metabolite gene clusters are regions within the plant genome that encode enzymes and proteins involved in the biosynthesis of secondary metabolites. Helianthus annuus L. is a significant oilseed plant with economic importance. This study aims to comprehensively identify secondary metabolite biosynthetic gene clusters within H. annuus using bioinformatics tools, shedding light on the functions of the enzymes involved. In this study, the plantiSMASH software was utilized to predict secondary metabolite biosynthetic gene clusters in H. annuus. The results from plantiSMASH were analyzed to identify the biosynthetic gene clusters for secondary metabolites on each chromosome. The biological and molecular functions of the enzymes within these clusters were predicted using data from the relevant articles. According to the obtained data, H. annuus lacks a biosynthetic gene cluster on chromosomes four, seven, and fifteen. The identified gene clusters in this plant are polyketide, saccharide, saccharide-terpene, alkaloid, putative, and terpene. The enzyme categories found in secondary metabolite biosynthetic gene clusters include Methyltransferase, Ketosynthase, Glycosyltransferase, BAHD acyltransferase, Dioxygenase, CoA-ligase, Epimerase, PRISE enzymes, Prenyltransferase, Oxidoreductase, Aminotransferase, Copper amine oxidase, Cytochrome P450, Terpene synthase, and Pictet-Spengler enzyme (Bet v1). This comprehensive analysis provides a foundation for further investigations into the biosynthesis of secondary metabolites in H. annuus , offering valuable insights for researchers exploring the medicinal and pharmaceutical potential of this plant species. [ABSTRACT FROM AUTHOR]

Premise Methods Results Conclusions The use of hybrid breeding systems to increase crop yields has been the cornerstone of modern agriculture and is exemplified in the breeding and improvement of cultivated sunflower (Helianthus annuus). However, it is poorly understood what effect supporting separate breeding pools in such systems, combined with continued selection for yield, may have on leaf ecophysiology and specialized metabolite variation.We analyzed 288 lines of cultivated H. annuus to examine the genomic basis of several specialized metabolites and agronomically important traits across major heterotic groups.Heterotic group identity supports phenotypic divergences between fertility restoring and cytoplasmic male‐sterility maintainer lines in leaf ecophysiology and specialized metabolism. However, the divergence is not associated with physical linkage to nuclear genes that support current hybrid breeding practices in cultivated H. annuus. Additionally, we identified four genomic regions associated with leaf ecophysiology and specialized metabolism that colocalize with previously identified QTLs for quantitative self‐compatibility traits and with S‐protein homolog (SPH) proteins, a recently discovered family of proteins associated with self‐incompatibility and self/nonself recognition in Papaver rhoeas (common poppy) with suggested conserved downstream mechanisms among eudicots.Further work is necessary to confirm the self‐incompatibility mechanisms in cultivated H. annuus and their relationship to the integrative and polygenic architecture of leaf ecophysiology and specialized metabolism in cultivated sunflower. However, because self‐compatibility is a derived quantitative trait in cultivated H. annuus, trait linkage to divergent phenotypic traits may have partially arisen as a potential unintended consequence of historical breeding practices and selection for yield. [ABSTRACT FROM AUTHOR]

Thrips, Frankliniella intonsa, is a highly polyphagous pest with a worldwide distribution. F. intonsa‐infested sunflower seeds show marked visual damage. The study findings revealed that significantly more F. intonsa infested confection sunflower compared to oilseed sunflower, via olfactometer bioassay studies, we found that compared with the flower and pollen of oilseed sunflowers, those of confection sunflowers attract F. intonsa. Considering this discrepancy in the preference of F. intonsa on oilseed and confection sunflowers, the volatiles of the flower and pollens of two sunflowers were analysed by gas chromatography‐mass spectroscopy. The behavioural responses of F. intonsa were assessed for these compounds using Y‐tube bioassays. Geranyl bromide, a unique volatile component of oilseed sunflowers, induced an assertive approach‐avoidance behaviour in F. intonsa, whereas the unique component ethyl isovalerate in confection sunflowers attracted F. intonsa. F. intonsa adults demonstrated significant attraction to the blends of confection sunflowers. Furthermore, field verification revealed that intercropping confection and oilseed sunflowers could effectively control F. intonsa. The study provided insights into the chemical cues used by F. intonsa in locating hosts. Therefore, oilseed sunflowers can be used as repellent plants to prevent F. intonsa invasion. Summary Statement: The damage to sunflower seeds is caused by Frankliniella intonsa. A previous study found that the seed damage rate of oilseed sunflower varieties was lower than that of confection sunflower varieties. Understanding the underlying reason behind this distinction can help us understand the behaviour of F. intonsa, thereby aiding their control. Our research shows that the attraction of sunflower volatiles to F. intonsa is the root cause of the difference in F. intonsa population. Geranyl bromide, a unique volatile component of oilseed sunflowers, induces an assertive approach‐avoidance behaviour in F. intonsa, whereas the unique component ethyl isovalerate in confection sunflowers attracts F. intonsa. F. intonsa adults demonstrated significant attraction to the blends of confection sunflowers. Furthermore, field verification revealed that intercropping confection and oilseed sunflowers could effectively control F. intonsa. The study provided insights into the chemical cues used by F. intonsa in locating hosts. Therefore, oilseed sunflowers can be used as repellent plants to prevent F. intonsa invasion. [ABSTRACT FROM AUTHOR]

Sunflower (Helianthus annuus) is a widely cultivated crop that exhibits a trait known as capitulum (or head) inclination at maturity. This trait is influenced by various structural factors, including head weight, stem traits, and plant height. A sunflower head should be at an angle at which the head faces the ground to avoid damage from the sun and birds. While this desired inclination range is known, current methods, including visual estimation and a model of measuring inclined length of the stem, fail to provide precise measurements of angle. This study introduces novel approaches to mathematically measure the head inclination angle. The research, which was conducted over the 2022 and 2023 growing seasons, involved an aluminum rod equipped with a ruler and a digital protractor to measure various height and angle components. Using the data collected, three methods were applied for measuring inclination: a previously published model as a control, a trigonometry‐based approach using angle and height measurements, and other model‐based approaches. A linear model resulted in a formula to calculate the head angle of any plant based solely on two height measurements, the highest point of the plant at both bloom (R5) and maturity (R9). Calculations of heritability and correlation suggest this method has created a precise alternative to existing estimation methods. The resulting formula has the potential to be paired with measurements from high‐throughput phenotyping methods, such as those facilitated with drones and ground robots, to fully automate the process of collecting head inclination data. Core Ideas: Sunflower head inclination angle can be estimated using the height of plants at two distinct growth stages.Heritability and correlation suggest an improvement over existing estimation methods.The height measurements required are expected to become automated with high‐throughput phenotyping methods. [ABSTRACT FROM AUTHOR]

Sunflower (Helianthus annuus L.) capacity to synthesize and accumulate soluble carbohydrates that will ultimately contribute to grain filling, either via actual photosynthesis or previously stored reserves, has been largely neglected despite its relevance regarding crop yield. The present work is aimed at studying the effect of photoassimilate availability on the dynamics of production and distribution of soluble carbohydrates in the plant during vegetative and reproductive phases. Plant photoassimilate availability was modified from production crop level in two hybrids during two field experiments by shading or thinning plants, which resulted in a range of intercepted radiation between 20 and 300 MJ per plant and also by removal of the main sink, the capitulum. Plants under higher light availability developed larger leaves and accumulated much more biomass than shaded ones. In general, plant sugar storage increased up to flowering and was highest in the developing capitulum and upper stem internodes. Increasing light availability led to a strong growth promotion that was especially remarkable in the capitulum and stem upper internodes, which precluded an increase in sugar concentration in these parts. Capitulum removal led to sugar remobilization to the plant base, resulting in a strong growth promotion of roots, basal stem internodes, and even in leaves from the lower strata, showing an extremely high plasticity of all sunflower organs in response to photoassimilates. These results also suggest that sugars per se may drive plastic changes of organ size ultimately conditioning plant capacity to store sugars and crop yield. [ABSTRACT FROM AUTHOR]

In modern agriculture, nano-priming represents an innovative approach, harnessing the power of nanotechnology to enhance crop yields and nutrition. However, to effectively harness the potential of nanoparticles (NPs) for agriculture applications, understanding their mode of action and optimal application rates for positive effects on microgreen growth and physiology is critical. In this interdisciplinary study, we investigated the priming of sunflower seeds with a range of concentrations (25, 50, and 100 mg/L) of ferric oxide (Fe2O3) nanoparticles (FeNPs) and compared them with control samples. Our findings revealed a significant increase in plant biomass, leaf size, and photosynthetic activity in treated samples. The activities of photosystems I and II increased with higher FeNPs concentration. The treated samples exhibited elevated levels of total phenolics, anthocyanin, and antioxidant enzyme activity, along with increased macronutrients and micronutrients. These findings highlight the potential of FeNPs as a promising tool for enhancing plant growth and physiology in sunflower microgreens. [ABSTRACT FROM AUTHOR]

The research on actinobacteria isolated from traditional medicinal plants is limited. Here, four new Streptomyces isolates (Ha1, Pp1, UzK and UzM) were obtained from the rhizospheres of Helianthus annuus, Pongamia pinnata and Ziziphus mauritiana, frequently utilized in Indian traditional medicine. The Streptomyces isolates aqueous extracts were studied alone against the growth of the Cryptococcus neoformans H99 reference strain, the fluconazole-tolerant T1-5796 and 89–610 strains, three histone deacetylase (HDAC) genes mutant strains, C. gattii NIH198, Candida albicans, C. glabrata, C. parapsilosis and C. tropicalis to determine minimum inhibitory concentration (MIC). Next, the extracts were employed in combination with aluminium-phthalocyanine chloride nanoemulsion-mediated photodynamic therapy to evaluate a possible interaction. We demonstrated that the C. neoformans T1-5796 fluconazole-tolerant strain was more severely inhibited by the Pp1 isolate extract (MIC: 6 mg mL−1) than H99, which was not inhibited. Growth inhibition of the HDAC null mutants was more prominent for the extract of the UzM isolate, showing inhibition at 2 mg mL−1. The UzM extract was also the most effective in hindering the Candida species proliferation, with MIC values ranging from 10 to 40 mg mL−1. The four Streptomyces extracts, especially UzK and UzM, significantly enhanced the antifungal effect of the photodynamic therapy. Our results indicate these Streptomyces isolates as sources of novel metabolites which could potentiate the effect of photodynamic therapy in controlling yeasts superficial infections. [ABSTRACT FROM AUTHOR]

In saline conditions, establishing healthy seedlings is crucial for the productivity of sunflowers (Helianthus annuus L.). Excessive potassium (K+) from irrigation water or overfertilization, similar to sodium (Na+), could adversely affect sunflower growth. However, the effects of salt stress caused by varying K/Na ratios on the establishment of sunflower seedlings have not been widely studied. We conducted a pot experiment in a greenhouse, altering the K/Na ratio of a soil solution to grow sunflower seedlings. We tested three saline solutions with K/Na ratios of 0:1 (P0S1), 1:1 (P1S1), and 1:0 (P1S0) at a constant concentration of 4 dS m−1, along with a control (CK, no salt added), with five replicates. The solutions were applied to the pots via capillary rise through small holes at the bottom. The results indicate that different K/Na ratios significantly influenced ion-selective uptake and transport in crop organs. With an increasing K/Na ratio, the K+ concentration in the roots, stems, and leaves increased, while the Na+ concentration decreased in the roots and stems, with no significant differences in the leaves. Furthermore, an excessive K/Na ratio (P1S0) suppressed the absorption and transportation of Mg2+, significantly reducing the Mg2+ concentration in the stems and leaves. A lower leaf Mg2+ concentration reduced chlorophyll concentration, impairing photosynthetic performance. The lowest plant height, leaf area, dry matter, and shoot/root ratio were observed in P1S0, with reductions of 27%, 48%, 48%, and 13% compared to CK, respectively. Compared with CK, light use efficiency and CO2 use efficiency in P1S0 were significantly reduced by 13% and 10%, respectively, while water use efficiency was significantly increased by 9%. Additionally, improved crop morphological and photosynthetic performance was observed in P1S1 and P0S1 compared with P1S0. These findings underscore the critical role of optimizing ion composition in soil solutions, especially during the sensitive seedling stage, to enhance photosynthesis and ultimately to improve the plant's establishment. We recommend that agricultural practices in saline regions incorporate tailored irrigation and fertilization strategies that prioritize optimal K/Na ratios to maximize crop performance and sustainability. [ABSTRACT FROM AUTHOR]

The exogenous application of oxalic acid is a potential approach to amplifying phytoremediation performance on Cd-contaminated soils. However, few studies explore the optimal oxalic acid application regime from a perspective of coupling different concentrations and timings to maximize Cd removal rate. Given this, a pot experiment was conducted using oil sunflower (Helianthus annuus L.) as the test plant. Oxalic acid was added to the pots at concentrations of 1, 2, 3, 4, 5, and 6 mmol/kg at 20, 30, 40, and 50 days after emergence. A control (CK) without exogenous oxalic acid was also included. We examined the discrepancies in various soil Cd forms, sunflower height, plant non-protein thiol (NPT) levels, and soil Cd remediation efficiency under different oxalic acid application regimes. The results showed that applying oxalic acid at a concentration of 4 mmol/kg reduced the proportion of Fe-Mn oxide Cd and organic Cd compared to the control (CK), while increased the proportion of available Cd. The optimal application time is 30 or 40 days after emergence. The addition of exogenous oxalic acid promoted the growth of sunflowers, with the greatest increase in plant height observed when 4 mmol/kg oxalic acid was applied at 30 days after emergence. Exogenous oxalic acid enhanced the absorption of Cd by sunflower roots, with the total Cd accumulation in roots, stems, and leaves being higher than in the control (CK). When 4 mmol/kg oxalic acid was applied at 30 days after emergence, the total Cd accumulation in roots, stems, and leaves was highest. Under different application times and concentration levels of oxalic acid, Cd accumulation was highest in roots, followed by leaves, with stems showing the lowest accumulation. The NPT content in each part is as follows: root > stem > leaf. Applying 5 mmol/kg oxalic acid after 30 days of sunflower emergence resulted in relatively higher total NPT content in roots, stems, and leaves compared to the control (CK). The TOPSIS model was used for comprehensive evaluation, which showed that 4 mmol/kg oxalic acid application at 30 days after emergence could be used as the optimal oxalic acid application regime for phytoremediation. These findings indicate that the addition of oxalic acid effectively promoted the absorption of Cd by sunflower and increased the efficiency of Cd removal from the rhizosphere soil, with the optimal removal of soil Cd achieved by applying oxalic acid at a concentration of 4 mmol/kg 30 days after the emergence of oilseed sunflower seedlings. [ABSTRACT FROM AUTHOR]

The pathogen Plasmopara halstedii, causing downy mildew (DM), is a widespread sunflower disease which can be controlled by single dominant genes. Wild Helianthus annuus have been a valuable source of vertical resistance to control P. halstedii, but such resistance may eventually be overcome by new races of the pathogen. Alternatively, quantitative, or partial resistance, is more stable and may be combined with vertical resistance to prevent DM outbreaks. We assessed the responses of six populations of wild H. annuus naturalized in Argentina to race 710 of P. halstedii. We examined: 1) the aerial phenotype (including seedling death) using two damage scales and three disease indices, 2) the growth of the pathogen along the hypocotyls, and 3) the presence of the pathogen in the root system. We found that the evaluated sunflower wild populations had lower disease levels than the susceptible cultivated controls. A histologic analysis showed that the wild H. annuus seedlings showed cellular reactions (e.g. necrosis and the deposit of materials on the walls of invaded cells) to restrict the pathogen's growth, allowing the identification of two possible types of resistance: type I, when the growth of the pathogen was limited to the base of the hypocotyls, and type II, when the pathogen managed to invade the entire length of the hypocotyls. The wild sunflower populations also showed differential responses to root infections. A quantitative or partial genetic resistance, rather than resistance based on major genes, seems to be operating in the sampled populations. The individuals found to be resistant in each population represent promising germplasm for sunflower breeding. [ABSTRACT FROM AUTHOR]

Potato (Solanum tuberosum L.) dry rot due to fungal infections causes the loss of a significant amount of potatoes. In this study, the antifungal effects of sunflower (Helianthus annuus L.) extracts against Fusarium sulphureum were investigated. The results of in vitro antifungal tests showed that all four sunflower extracts significantly inhibited the growth of F. sulphureum. Notably, the optimal inhibitory concentrations of ethyl acetate extract from sunflower disk (EESD), ethyl acetate extract from sunflower stalk (EESS), petroleum ether extract from sunflower disk (PESD) and petroleum ether extract from sunflower stalk (PESS) against F. sulphureum were 160 mg/mL, 160 mg/mL, 240 mg/mL, and 240 mg/mL, respectively. In addition, these extracts significantly inhibited the activities of polygalacturonase (PG), polymethyl-galacturonase (PMG), carboxymethyl cellulase (Cx), and β-glucosidase (β-Glu) secreted by F. sulphureum in three potato varieties: Longshu No.7, Longshu No.10 and Xindaping. These results provide a theoretical foundation for the biological control of potato dry rot. [ABSTRACT FROM AUTHOR]

Waterlogging affects a high proportion of cultivated land worldwide. Sunflower, soybean and sorghum growth and yield can be affected differently depending on the moment and duration of waterlogging stress. If stress conditions occur during the critical period for yield potential definition (flowering in, sunflower and sorghum and end of pod formation in soybean) they directly reduce grain number, but if the stress occurs during the grain‐filling period, grain weight would be affected. The aim of this study focuses on determining the effects of the moment and duration of waterlogging stress on the yield and its components in sunflower, soybean and sorghum. This information will be useful to understand the effects of waterlogging on yield and to choose a suitable crop or sowing date based on predicted weather conditions for a certain place. To achieve this objective, four experiments were conducted at the Experimental Station of INTA (Reconquista, Santa Fe, Argentina). The effect of the waterlogging in terms of moment (vegetative, critical and grain‐filling periods) and duration (3, 7 and 10 days) on the three crops was evaluated. Sunflower expressed the most negative impact of waterlogging during the vegetative stages (26, 78 and 98% of yield losses with 3, 7 and 10 days, respectively) while soybean suffered major reductions when the stress occurred during the critical period (5%–17% of yield loses). Sorghum did not express any negative responses for the moments and durations tested. This study suggests that the critical period for a waterlogging event differs, according to crops, from the critical period cited for other stresses. Moreover, the magnitude of the damage will mainly depend on the duration of the event. Further studies are needed to elucidate different physiological responses of the species during waterlogging stress. [ABSTRACT FROM AUTHOR]

This study evaluates the phytotoxic potential of methanolic extracts from six Asteraceae species: Wedelia chinensis, Helianthus annuus, Cosmos bipinnatus, Tagetes erecta, Tithonia diversifolia, and Zinnia elegans. The extracts were tested at concentrations of 0.03, 0.1, 0.3, and 1.0 g/mL to assess their inhibitory effects on the radicle and hypocotyl lengths of Echinochloa crus‐galli and Echinochloa colona. The two most potent species, C. bipinnatus and T. diversifolia, were further evaluated using extracts from their roots, stems, and leaves. Among these, C. bipinnatus leaf extracts showed the most significant phytotoxicity and were tested at 20, 40, and 60 days of plant age. At 0.03 g/mL, C. bipinnatus extract inhibited the hypocotyl and radicle lengths of E. colona by 23.01% and 56.45%, and E. crus‐galli by 8.5% and 36.35%, respectively. At 1.0 g/mL, the extract inhibited the hypocotyl lengths of E. colona and E. crus‐galli by 97.54% and 88.15%, and the radicle lengths by 93.52% and 99.99%, respectively. The 60‐day‐old C. bipinnatus leaf extract exhibited the highest inhibitory effect, correlating with the identification of key allelochemicals such as cinnamic acid, caffeic acid, coumaric acid, ferulic acid, 2‐4 dimethohydroxy benzoic acid, and salicylic acid. These findings suggest that the 60‐day‐old C. bipinnatus leaf extracts have strong potential for use in the biological control of these weed species, offering a promising avenue for the development of natural herbicides. [ABSTRACT FROM AUTHOR]

Phytoremediation is a rapidly expanding process due to its technical and economic viability. The objective of this work was to evaluate the phytoremediation potential of Helianthus annuus in three cultivation media: artificially contaminated Catalão soil, hydroponics and roadside soil. In hydroponics, ZnCl2 doses 0.32 mgL− 1, 29.94 mgL− 1, 60.06 mgL− 1, 119.94 mgL− 1 were used. While in the artificially contaminated soil, the doses were 0 mgkg− 1, 299 mgkg− 1, 599 mgkg− 1, 1498 mgkg− 1. Physiological analyzes made it possible to demonstrate that treatments T3 and T4, with the highest concentrations of the metal, inhibited growth and promoted darkening of the roots. The highest Zn contents occurred in the aerial part. The results indicated that Helianthus annuus was classified as hyperaccumulator due to its ability to accumulate high levels of Zn mainly in artificially contaminated soil. [ABSTRACT FROM AUTHOR]

Daily changes in the content of phytohormones accumulating in the hypocotyls of young sunflower seedlings that grow under a 14/10-h light-to-dark (LD) photoperiod were followed using LC–MS. The objective of the work was to investigate whether the presence of light and light transitions lead to visible changes visible in phytohormone levels on the sixth day after the onset of germination. The LC–MS technique used allowed the simultaneous detection of more than one hundred individual phytohormone derivatives, of which the daily accumulation patterns were determined for nearly fifty members. The daily changes in phytohormone levels followed specific patterns for each phytohormone. There were differences between the daytime and nighttime levels, most likely reflecting the effects of light on phytohormone metabolism. A significant difference was found between cytokinins (CKs) and all other phytohormones, so that CK group of phytohormones may be considered to have a separate role in hypocotyl elongation. Prolonged daytime (postponed dusk) resulted in a rapid disruption of rhythmic hypocotyl elongation and it triggered an acute light stress response that was evident in increased levels of a number of important phytohormones from all groups except CKs. However, this light stress, termed ARELD (Acute Response to Extended Light Duration), was not present in control plants grown under continuous light conditions. The data suggest that sunflower has means to adapt to the potentially stressful conditions of continuous light (LL). The qPCR-RT study of the isoforms of circadian clock-associated genes HaLHY, HaTOC1, HaELF3, and HaPIF3 revealed diurnal rhythms under both LD and LL conditions in which the peaks were synchronized and shifted toward the subjective dawn. [ABSTRACT FROM AUTHOR]

Sunflower (Helianthus annuus L.), known for its adaptability and high yield potential, is vital in global edible oil production. Estimating genetic diversity is a key pre-breeding activity in crop breeding. The current study comprised of 48 genotypes which were assessed for their biometrical traits at department of Oilseeds, Tamil Nadu Agricultural University, during the rainy season of 2022. The lines were subsequently characterised using 103 simple sequence repeat (SSR) markers for molecular diversity analysis. The results indicated that the net nucleotide distances indicated varying genetic divergence, with subpopulations II and V showing the highest (0.056) and I and IV the lowest (0.014). Subpopulation IV exhibited the highest heterozygosity (0.352), while subpopulation III had the lowest heterozygosity and a low Fst (0.173). Principal components analysis (PCA) and hierarchical cluster analysis were employed for assessing the morphological diversity, facilitating genotype grouping and parent selection for breeding programs. The first four components cumulatively accounted for 86.72% of the total variation. Cluster Analysis grouped 48 sunflower genotypes into three clusters based on genetic diversity. COSF 13B stands out for its high head diameter, oil content, seed yield, and oil yield based on mean performance of morphological data. Principal coordinate analysis (PCoA) mirrored the groupings from the Neighbor Joining method, with the first three components explaining 27.24% of the total variation. Molecular data analysis identified five distinct clusters among the germplasm. By integrating morphological and molecular marker data with genetic distance analysis, substantial diversity was revealed with the genotypes RHA 273 and GMU 325 consistently demonstrated high oil yield per plant. The genotypes GMU 477, GMU 450, COSF 13B, RHA 102, CMS 1103B, and RHA GPR 58 have been identified as suitable parents for enhancing oil content in sunflower breeding programs. These findings also aid in selecting SSR markers for genotype characterization and in choosing diverse parents for breeding programs. [ABSTRACT FROM AUTHOR]

The cultivation of sunflower (Helianthus annuus L.) as a cut flower stands out in floriculture due to its aesthetic beauty and commercial value. Understanding how cut sunflower genotypes adapt to different edaphoclimatic regions and management practices is essential to optimize flower quality and productivity. This study aimed to evaluate the effect of plant density and location on the development, growth, and quality of cut sunflower in tropical and subtropical environments. Plant densities of 10, 20, 30, 40, and 50 plants/m2 were evaluated in tropical climate and subtropical climate using a randomized block design in a factorial scheme. Results showed significant differences between locations for plant height, capitulum and stem diameter, final number of leaves, leaf area, leaf area index, phyllochron, and the developmental cycle. Plant density significantly influenced these variables except for plant height and developmental cycle. The interaction between location and plant density was significant only for capitulum diameter and final leaf number. The findings indicate that both planting density and location significantly influence the developmental cycle of cut sunflowers, with lower densities favoring more robust plants at harvest. A density of 30 plants/m2 is recommended for efficient space use without significantly compromising floral stem quality. All produced stems are marketable, suggesting that adjusting planting density can optimize production without compromising quality, adapting to specific regional conditions. [ABSTRACT FROM AUTHOR]

Trichomes play a key role in both heavy metal tolerance and herbivory defense, and both stressors have been shown to induce increased trichome density. However, the combined effect of these stressors on trichome density in general, and specifically on metal-hyperaccumulating plants, has yet to be examined. The aim of this study was to test the effect of cadmium availability and herbivory on leaf trichome density and herbivore deterrence in the metal hyperaccumulator Helianthus annuus. To test this, H. Annuus plants were grown in control pots or pots inoculated with 10 mg/kg cadmium and were subjected to either no herbivory or simulated herbivory using mechanical damage and foliar jasmonic acid application. Herbivore deterrence was tested in a feeding assay using Spodoptera littoralis caterpillars. Interestingly, while the trichome density of H. annuus increased by 79% or 53.5% under high cadmium availability or simulated herbivory, respectively, it decreased by 26% when the stressors were combined. Furthermore, regardless of cadmium availability, simulated herbivory induced a 40% increase in deterrence of S. littoralis. These findings suggest that the combination of metal availability and herbivory might present excessive stress to hyperaccumulators. Moreover, they suggest that the risk of metal bioaccumulation in phytoremediation can be reduced by simulated herbivory. [ABSTRACT FROM AUTHOR]

In this work, sunflower (Helianthus annuus) seed pericarp (SSPC) was converted into mesoporous activated carbon (SSPCAC) via microwave-assisted ZnCl2 activation to be a cost-effective and renewable adsorbent for crystal violet (CV) dye removal. The obtained SSPCAC exhibits a preferable surface area of 641 m2/g with mesoporous characteristics. A statistical optimization by Box-Behnken Design (BBD) with Response Surface Methodology (RSM) was adopted to achieve the optimal operational conditions for CV dye including SSPCAC dose, solution pH, and contact time. Moreover, desirability functions confirm the maximum CV removal of 91% was attended at SSPC-AC dose (0.083 g/100 mL), solution pH (9.8), and contact time (5.38 min). Thus, the equilibrium data were best described by the Langmuir isotherm model with a maximum adsorption capacity of 111.9 mg/g at 25 0C. Thus, the adsorption kinetics were well described by a pseudo-second order (PSO) model. The adsorption mechanism of CV onto SSPCAC surface can be assigned to the electrostatic attraction, hydrogen bonding, pore filling, and pi-pi interactions. This research highlights the potential of sunflower seed pericarp as a renewable precursor for activated carbon production with promising applications in toxic dye removal from wastewater. [ABSTRACT FROM AUTHOR]

Dependence on reclaimed wastewater and biosolids for agronomic use in semi-arid and arid regions is progressively increasing across the globe. The impact of contamination of treated water with residues of recalcitrant pharmaceuticals on the ecosystem is now one of the major environmental concerns. Common sunflower, Helianthus annuus (H. annuus), has been reported to remove one of the recalcitrant pharmaceuticals, carbamazepine (CBZ). However, it's potential to tolerate CBZ is not yet characterized. For this, the plant cell suspension system of H. annuus (6.67 g DWL-1) was used as a model system and within 6 h of exposure to CBZ (15 ppm), 39.47 ± 6.8% was found to be removed with initial removal rate of 0.987 ± 0.17 mg L −1 h−1. The adsorption equilibrium data was fitted with the Freundlich isotherm and the removal kinetics of CBZ onto plant cells of H. annuus was correlated well with Elovich kinetics. Also, no significant change in the viability and antioxidant levels (Ascorbate peroxidase and Glutathione peroxidase) was observed in the plant cells exposed to higher concentrations of CBZ (15 ppm), demonstrating high tolerance. The finding strongly indicates that in-vitro system of H. annuus holds significant promise as a robust platform for investigating the intricate mechanisms underlying its tolerance to CBZ. [ABSTRACT FROM AUTHOR]

Sunflower (Helianthus annuus L.) plays an essential role in meeting the demand for edible oil worldwide. The yield of sunflower seeds encompasses several component traits, including the disc diameter. Over three consecutive years, 2019, 2020, and 2022, we assessed phenotypic variation in disc diameter across a diverse set of sunflower accessions (N = 342) in replicated field trials. Upon aggregating the phenotypic data from multiple years, we estimated the broad sense heritability (H2) of the disc diameter trait to be 0.88. A subset of N = 274 accessions was genotyped by using the tunable genotyping‐by‐sequencing (tGBS) method, resulting in 226,779 high‐quality SNPs. Using these SNPs and the disc diameter phenotype, we conducted a genome‐wide association study (GWAS) employing two statistical approaches: the mixed linear model (MLM) and the fixed and random model circulating probability unification (farmCPU). The MLM and farmCPU GWAS approaches identified 106 and 8 significant SNPs located close to 53 and 21 genes, respectively. The MLM analysis identified two significant peaks: a prominent signal on chromosome 10 and a relatively weaker signal on chromosome 16, both of which were also detected by farmCPU. The genetic loci associated with disc diameter, as well as the related candidate genes, present promising avenues for further functional validation and serve as a basis for sunflower oil yield improvement. [ABSTRACT FROM AUTHOR]

Sunflower (Helianthus annuus) is a globally significant field crop, and disease resistance is crucial for ensuring yield stability and crop quality. Verticillium dahliae is a notorious soilborne pathogen that causes Verticillium Wilt (VW) and threatens sunflower production worldwide. In this study, we conducted a comprehensive assessment of sunflower resistance to V. dahliae across 231 sunflower cultivar lines, from the Sunflower Association Mapping (SAM) population. We employed EMMAX and ridge regression best linear unbiased prediction (rrBLUP) and identified 148 quantitative trait loci (QTLs) and 23 putative genes associated with V. dahliae resistance, including receptor like kinases, cell wall modification, transcriptional regulation, plant stress signalling and defense regulation genes. Our enrichment and quantitative real-time PCR validation results highlight the importance of membrane vesicle trafficking in the sunflower immune system for efficient signaling and defense upon activation by V. dahliae. This study also reveals the polygenic architecture of V. dahliae resistance in sunflowers and provides insights for breeding sunflower cultivars resistant to VW. This research contributes to ongoing efforts to enhance crop resilience and reduce yield losses due to VW, ultimately benefiting sunflower growers and the agricultural sector. [ABSTRACT FROM AUTHOR]

The microbiological and biochemical properties of a goat cheese produced using Helianthus annuus (sunflower) seed extract as a coagulant and the potentially probiotic autochthonous culture Limosilactobacillus mucosae CNPC007 were examined in comparison to a control cheese devoid of the autochthonous culture. Throughout a 60-day storage period at 6 ± 1 °C, lactobacilli maintained a count of above 8 log CFU/g. Additionally, its viability in cheeses subjected to the in vitro gastrointestinal conditions demonstrated improvement over this period. Specifically, the recovery of lactobacilli above 6 log CFU/g was observed in 16.66% of the samples in the first day, increasing to 66.66% at both 30 and 60 days. While total coliforms were detected in both cheese trials, this sanitary parameter exhibited a decline in L. mucosae cheeses during storage, falling below the method threshold (<3 MPN/g) at 60 days. This observation suggests a potential biopreservative effect exerted by this microorganism, likely attributed to the higher acidity of L. mucosae cheeses at that point (1.80 g/100 g), which was twice that of the control trial (0.97 g/100 g). Furthermore, distinct relative proportions of >30 kDa, 30–20 kDa, and <20 kDa proteins during storage was verified for L. mucosae and control cheeses. Consequently, either the H. annuus seed extract or the L. mucosae CNPC007 autochthonous culture influenced the biochemical properties of the cheese, particularly in terms of proteolysis. Moreover, L. mucosae CNPC007 acidification property resulted in a biopreservative effect throughout the storage period, indicating the potential as a promising source of probiotics for this product. [ABSTRACT FROM AUTHOR]

Intracellular plant defense against pathogens is mediated by a class of disease resistance genes known as NB‐LRRs or NLRs (R genes). Many of the diseases these genes protect against are more prevalent in regions of higher rainfall, which provide better growth conditions for the pathogens. As such, we expect a higher selective pressure for the maintenance and proliferation of R genes in plants adapted to wetter conditions. In this study, we enriched libraries for R genes using RenSeq from baits primarily developed from the common sunflower (Helianthus annuus) reference genome. We sequenced the R gene libraries of Silphium integrifolium Michx, a perennial relative of sunflower, from 12 prairie remnants across a rainfall gradient in the Central Plains of the United States, with both Illumina short‐read (n = 99) and PacBio long‐read (n = 10) approaches. We found a positive relationship between the mean effective annual precipitation of a plant's source prairie remnant and the number of R genes in its genome, consistent with intensity of plant pathogen coevolution increasing with precipitation. We show that RenSeq can be applied to the study of ecological hypotheses in non‐model relatives of model organisms. [ABSTRACT FROM AUTHOR]

Nutrient use efficiency may be reduced due to overuse of fertilizers, leaching, volatilization and denitrification in most Indian soils. Nano urea and other micronutrients are used as foliar applications to reduce losses and increase agriculture production. Considering this, a field experiment was carried out to check the different levels of sulphur (S) and boron (B) along with nano urea on sunflower's growth, yield and quality. The treatment consisted of two levels of sulphur (30 & 45 kg/ha) and boron (100 & 200 ml/ha) along with nano urea except for control. The experiment was laid out in a Randomized Block Design (RBD) with nine treatments (T0 to T8). The results revealed that the crop raised with nano urea plus 45 kg/ha S and 200 ml/ha B significantly impacted sunflowers growth, yield and quality. The highest values in plant height (181.6 cm), no. of leaves (31.7), stem girth (11.16 cm), dry matter production (121.5 g/plant), and Leaf area index (5.06), diameter of the head (19.59 cm), no. of filled seeds/head (753.3), weight of 100 seeds (5.46) were registered in T8. Ultimately, treatment T8 has an impeccable influence on improving seed yield (3140.8 kg/ha) and stover yield (5570.0 kg/ha). The same treatment also showed maximum oil content (44.20 %), oil yield (1388.34 kg/ha), and crude protein content (16.07 %). The study suggests that the sulphur, boron, and nano urea had a synergistic relationship, and proper dosages, application methods, and time for the above nutrients can significantly improve sunflower production. [ABSTRACT FROM AUTHOR]

The response of mesophyll conductance (gm) to CO2 plays a key role in photosynthesis and ecosystem carbon cycles under climate change. Despite numerous studies, there is still debate about how gm responds to short‐term CO2 variations. Here we used multiple methods and looked at the relationship between stomatal conductance to CO2 (gsc) and gm to address this aspect. We measured chlorophyll fluorescence parameters and online carbon isotope discrimination (Δ) at different CO2 mole fractions in sunflower (Helianthus annuus L.), cowpea (Vigna unguiculata L.), and wheat (Triticum aestivum L.) leaves. The variable J and Δ based methods showed that gm decreased with an increase in CO2 mole fraction, and so did stomatal conductance. There were linear relationships between gm and gsc across CO2 mole fractions. gm obtained from A‐Ci curve fitting method was higher than that from the variable J method and was not representative of gm under the growth CO2 concentration. gm could be estimated by empirical models analogous to the Ball‐Berry model and the USO model for stomatal conductance. Our results suggest that gm and gsc respond in a coordinated manner to short‐term variations in CO2, providing new insight into the role of gm in photosynthesis modelling. Summary statement: For photosynthesis modelling, the response of gm to short‐term CO2 changes is essential. Using variable J and carbon isotope discrimination methods, we showed that gm decreased with an increase in CO2 mole fraction, which contradicts the assumption of a constant gm in photosynthesis models. [ABSTRACT FROM AUTHOR]

The state of Rio Grande do Sul (RS) is the third largest sunflower producer in Brazil. This study verified the existence of linear relationships between grain yield, oil content, and oil yield in sunflower (Helianthus annuus L.) genotypes evaluated in RS. The data on grain yield (GY), oil content (OC), and oil yield (OY) were obtained from 73 sunflower cultivar trials in 21 municipalities in RS from 1999 to 2018. Scatter diagrams were createdto investigate the relationships between the variables GY, OC, and OY. Then, Pearson's linear correlation coefficient (r) was calculated between the variables, and the Student's t-test was performed at a 5% significance level. There is a positive and significant linear relationship between PG and OY. However, no linear relationship was found between grain yield and oil content in sunflower genotypes. Additionally, a positive linear association of high magnitude (r = 0.9672) was observed between grain yield and oil yield, while a low magnitude (r = 0.2245) was found between oil content and oil yield. [ABSTRACT FROM AUTHOR]

Insufficient dietary vitamin intake can lead to severe health conditions in humans. Improving the vitamin E (VE) content of food crops such as rice through breeding is an economical and effective means to alleviate this problem. In this study, Homogentisate phytyltransferase (HPT) and γ-tocopherol methyltransferase (γ-TMT), two genes derived from sunflower (Helianthus annuus L., a high VE species), were introduced into an elite rice (Oryza sativa L.) cultivar "Ningjing 7" for biofortification. We verified the successful expression of the two genes in multiple transformation events. High-performance liquid chromatography revealed that transgenic plants expressing either HaHPT alone or HaHPT and HaTMT accumulate more VE compared with the wild type. We also revealed that the level of α-tocopherol, the form of VE with the highest biological activity, had increased to 2.33 times in transgenic HaTMT plants compared with the wild type. Transcriptome analysis revealed that the expression levels of some chlorophyll synthesis pathway genes related to VE precursor synthesis significantly increased during grain filling in transgenic rice grains. No difference in agronomic traits was observed between the transgenic plants and their wild type except for a slightly reduced plant height associated with the transgenic plants. These data demonstrate that the heterologous expression of HaHPT gene is effective in increasing the total VE content, while HaTMT plays an important role in the relative abundance of α-tocopherol in rice grains. This study demonstrates a promising strategy for breeding rice with elevated VE content via metabolic engineering. [ABSTRACT FROM AUTHOR]

Imidacloprid, one of the latest members of the neonicotinoids, is a widely used synthetic organic insecticide. In this study, it was aimed to reveal the effects of 2 ppm, 4 ppm, and 8 ppm imidacloprid on antioxidant enzymes and lipid peroxidation in Helianthus annuus L. Tarsan-1018 oilseed sunflower leaves. As a result of the applications, sunflower leaves were collected and frozen in liquid nitrogen, then stored at -40 °C until analyses were conducted. Sunflower seeds were a registered variety and were obtained from Trakya Agricultural Research Institute. Imidacloprid were applied as foliar to the Sunflower plant grown under controlled conditions and samples were taken at 24. 48. and 72. hours. Superoxide dismutase (SOD), catalase (CAT), glutathione s-transferase (GST), glutathione (GSH), oxidized glutathione (GSSG) and malondialdehyde (MDA) analyzes were performed in the samples taken after the applications. As a result, it was determined that imidacloprid had different effects on the biochemical parameters of sunflower plant leaves. It was understood that imidacloprid used in ppm doses stimulated antioxidant defense and created stress responses in the plant, and as with all plant protection products, the importance of proper dosage and controlled use must not be overlooked. [ABSTRACT FROM AUTHOR]

Weedy sunflowers can cause severe yield losses and have recently been reported in several regions of Europe. We present the results of a survey of 24 grid cells 1 km2 in size on the distribution of weedy sunflowers in two different regions in Austria. Our results showed that weedy sunflowers (Helianthus annuus L.) occur in various crops (oil pumpkin, soybean, and maize). While most occurrences were small, a few fields were heavily infested (> 500 individuals) and weedy sunflowers reached cover values of up to 25%. The average number was 175 plants/km2 across all grid cells surveyed, with an average of 324 plants/km2 in the 13 infested grid cells and a maximum of approx. 1000 plants in the most heavily infested grid cell. The expression of recorded morphological traits (i.e., head number, height, and head diameter) varied considerably between populations of weedy sunflower, escaped sunflower, and cultivated sunflower. This study is the first to assess the infestation of weedy sunflowers in fields in Austria. We found evidence of the potentially substantial impact of weedy sunflowers on crop yields. Our findings highlight the need for further monitoring and controlling of weedy sunflowers in fields. [ABSTRACT FROM AUTHOR]

Deviation from uniform target plant population density in sunflower (Helianthus annuus L.) production may negatively affect canopy closure, yield, and grain quality. The objective of this study was to evaluate the effects of plant density heterogeneity on yield, quality, and canopy closure in confectionery and oilseed sunflowers. Field experiments consisted of fixed differences in the number of skips/doubles per plot while maintaining equal total number of plants, and stand gaps with proportional decreasing plant counts. These were conducted in Minnesota, Texas, and Colorado, USA. Experiments revealed that yield was occasionally influenced by heterogeneity, with more uniform stand density yielding higher; however, substantial changes in uniformity of plant density often resulted in no differences in yield. Confectionery sunflowers compensated for yield losses in thinner stands mainly by producing larger seeds (observed range of 0.1%–46.2% of seeds over a 9.53 mm sieve), while oilseed sunflowers increased seed production per head (as shown by invariable test weight across treatments within environments). Plants that were unharvestable for any cause (most often due to head rot disease or lodging) were more prevalent in less uniform stands, and faster canopy closure was achieved in uniformly spaced plants. Although sunflower is very resilient to stand uniformity issues, these findings underscore the importance of uniform sunflower plant spacing for effective weed suppression and crop performance and highlight the need for further research into sunflower yield compensation mechanisms. [ABSTRACT FROM AUTHOR]

The lesion nematode Pratylenchus brachyurus is a major pest of soybean in Brazil, managed by treating seed with nematicides and replacing corn for pearl millet (Pennisetum glaucum) and rattlepods (Crotalaria spp.) as a second crop. However, these cover crops are not profitable, leading growers to consider alternatives as cowpea, sunflower, and sorghum. In fact, although cowpea and sorghum are susceptible to P. brachyurus, cowpea is widely cultivated in the Brazilian Cerrado, where P. brachyurus is prevalent, and the forage sorghum 'BRS Ponta Negra' has been recommended for P. brachyurus management, based on field observations. Considering the increasing importance of cowpea in the Brazilian Cerrado, three pot trials were carried out to evaluate the host status of modern cowpea cultivars for P. brachyurus. Additionally, two pot trials were carried out to evaluate the effect of cowpea, sunflower, forage sorghum 'BRS Ponta Negra', pearl millet and showy rattlepod on soybean production in soil with P. brachyurus, taking account the scarcity of studies that prove the benefits of replacing corn for resistant crops on soybean grain production. The five cowpea cultivars tested were highly suitable hosts for P. brachyurus, supporting previous findings. Therefore, cowpea should be avoided in infested growing areas, especially as a second crop after soybean. Among the cover crops, only showy rattlepod consistently decreased P. brachyurus population density and increased soybean grain production, proving to be more effective than pearl millet in managing P. brachyurus. [ABSTRACT FROM AUTHOR]

Virus-Induced Gene Silencing (VIGS) is a versatile tool in plant science, yet its application to non-model species like sunflower demands extensive optimization due to transformation challenges. In this study, we aimed to elucidate the factors that significantly affect the efficiency of Agrobacterium-VIGS in sunflowers. After testing a number of approaches, we concluded that the seed vacuum technique followed by 6 h of co-cultivation produced the most efficient VIGS results. Genotype-dependency analysis revealed varying infection percentages (62–91%) and silencing symptom spreading in different sunflower genotypes. Additionally, we explored the mobility of tobacco rattle virus (TRV) and phenotypic silencing manifestation (photo-bleaching) across different tissues and regions of VIGS-infected sunflower plants. We showed the presence of TRV is not necessarily limited to tissues with observable silencing events. Finally, time-lapse observation demonstrated a more active spreading of the photo-bleached spots in young tissues compared to mature ones. This study not only offers a robust VIGS protocol for sunflowers but also provides valuable insights into genotype-dependent responses and the dynamic nature of silencing events, shedding light on TRV mobility across different plant tissues. [ABSTRACT FROM AUTHOR]

Short tandem repeat (STR) variation is rarely explored as a contributor to adaptive evolution. An intriguing mechanism involving STRs suggests that STRs function as "tuning knobs" of adaptation whereby stepwise changes in STR allele length have stepwise effects on phenotypes. Previously, we tested the predictions of the "tuning knob" model at the gene expression level by conducting an RNA-Seq experiment on natural populations of common sunflower (Helianthus annuus L.) transecting a well-defined cline from Kansas to Oklahoma. We identified 479 STRs with significant allele length effects on gene expression (eSTRs). In this study, we expanded the range to populations further north and south of the focal populations and used a targeted approach to study the relationship between STR allele length and gene expression in five selected eSTRs. Seeds from 96 individuals from six natural populations of sunflower from Nebraska and Texas were grown in a common garden. The individuals were genotyped at the five eSTRs, and gene expression was quantified with qRT-PCR. Linear regression models identified that eSTR length in comp26672 was significantly correlated with gene expression. Further, the length of comp26672 eSTR was significantly correlated with latitude across the range from Nebraska to Texas. The eSTR locus comp26672 was located in the CHUP1 gene, a gene associated with chloroplast movement in response to light intensity, which suggests a potential adaptive role for the eSTR locus. Collectively, our results from this targeted study show a consistent relationship between allele length and gene expression in some eSTRs across a broad geographical range in sunflower and suggest that some eSTRs may contribute to adaptive traits in common sunflower. [ABSTRACT FROM AUTHOR]

Fluorescence photography was used to evaluate the effects of bentazon, an herbicide that inhibits electron transport in photosystem II, on sunflower, taken as a model plant. We measured chlorophyll fluorescence to visualize the penetration, distribution, and effect of the herbicide on the plant. Our results showed that bentazon penetrates the leaf within 10–16 min, reaching full depth within 40 min. Also, we show that the herbicide is distributed along the conducting tissues of the leaf. The presence of necrotic spots, as well as the size of increased-fluorescence areas, were positively correlated to the concentration of herbicide. These findings suggest that fluorescence imaging may be a useful tool for observing the absorption and distribution of photosystem II-inhibiting herbicides in plants as an alternative to radioactive labeling in some cases. [ABSTRACT FROM AUTHOR]

One of the most important oil crops in the world, sunflower (Helianthus annuus L.), is recognized to help in soil phytoremediation. Heavy metal (HM) contamination is one of the most abiotic challenges that may affect the growth and productivity of such an important crop plant. We studied the influence of HM-contaminated soils on metal homeostasis and the potential hypertolerance mechanisms in two sunflower Egyptian cultivars (V120 and S53). Both cultivars accumulated significantly higher cadmium concentrations in their roots compared to their shoots during Cd and Zn/Cd treatments. Higher root concentrations of 121 mg g−1 dry weight (DW) and 125 mg g−1 DW were measured in V120 plants compared to relatively lower values of 111 mg g−1 DW and 105 mg g−1 DW in the roots of S53 plants, respectively. Cadmium contamination significantly upregulated the expression of heavy metal ATPases (HaHMA4) in the shoots of V120 plants. On the other hand, their roots displayed a notable expression of HaHMA3. This study indicates that V120 plants accumulated and sequestered Cd in their roots. Therefore, it is advised to cultivate the V120 cultivar in areas contaminated with heavy metals as it is a promising Cd phytoremediator. The current study confirms and provides new insights into the low Cd and Zn concentration responses of two cultivars of Helianthus annuus as potential HM phytoremediators. HMA3 and HMA4 mediated both root sequestration and reduced root-to-shoot translocation rates. Moreover, high CAT and POX activities may reduce oxidative damage and enhance plant tolerance. The V120 showed higher levels of Cd accumulation in its roots and could be a promising cultivar for the phytoremediation of this heavy metal. This work recalls that Cd tolerance is a trait that may vary among cultivars of the same species and should be taken into consideration in the phytomanagement of heavy metals in contaminated soils. [ABSTRACT FROM AUTHOR]

We present a reference genome for the federally endangered Gaviota tarplant, Deinandra increscens subsp. villosa (Madiinae, Asteraceae), an annual herb endemic to the Central California coast. Generating PacBio HiFi, Oxford Nanopore Technologies, and Dovetail Omni-C data, we assembled a haploid consensus genome of 1.67 Gb as 28.7 K scaffolds with a scaffold N50 of 74.9 Mb. We annotated repeat content in 74.8% of the genome. Long terminal repeats (LTRs) covered 44.0% of the genome with Copia families predominant at 22.9% followed by Gypsy at 14.2%. Both Gypsy and Copia elements were common in ancestral peaks of LTRs, and the most abundant element was a Gypsy element containing nested Copia/Angela sequence similarity, reflecting a complex evolutionary history of repeat activity. Gene annotation produced 33,257 genes and 68,942 transcripts, of which 99% were functionally annotated. BUSCO scores for the annotated proteins were 96.0% complete of which 77.6% was single copy and 18.4% duplicates. Whole genome duplication synonymous mutation rates of Gaviota tarplant and sunflower (Helianthus annuus) shared peaks that correspond to the last Asteraceae polyploidization event and subsequent divergence from a common ancestor at ∼27 MYA. Regions of high-density tandem genes were identified, pointing to potentially important loci of environmental adaptation in this species. [ABSTRACT FROM AUTHOR]

To maximize their fitness, plants have to adjust their allocation strategy according to their abiotic and biotic environments. Plants can use the ratio of red to far‐red light (R:FR) to sense neighbours, allowing them to modify their growth in response to aboveground competition.In this study, we used supplemental FR light to artificially lower the R:FR of the lower leaves of common sunflowers (Helianthus annuus) to examine how plants change their growth in response to the threat of neighbours. We combined this treatment with a nitrogen fertilization treatment to investigate how responses to neighbour‐detection interact with nitrogen limitation.Plants grown in low R:FR increased in height at the expense of root growth, resulting in nitrogen limitation that restricted leaf growth. However, we found that plants reduced their nitrogen investment into leaves in low R:FR. By weakening the nitrogen sink strength of these lower leaves before they experienced low photosynthetically active radiation, plants were able to preemptively allocate nitrogen to leaves higher in the canopy.Plants responded to the perception of neighbours by simultaneously diverting resources from root growth to stem elongation and from leaves threatened by neighbours to leaves that would pose a threat to neighbours. This whole‐plant response to neighbour‐detection enables plants to change their allocation in a way that simultaneously manages their limited nitrogen and prepares them for future light competition. Read the free Plain Language Summary for this article on the Journal blog. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Agroindustrial Technology / Jurnal Teknologi Industri Pertanian is the property of IPB University 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.)

Drought stress poses a significant obstacle to agricultural productivity, particularly in the case of oilseed crops such as sunflower (Helianthus annuus L.). Selenium (Se) is a fundamental micronutrient that has been recognized for its ability to enhance plant resilience in the face of various environmental stresses. The FH-770 sunflower variety was cultivated in pots subjected to three stress levels (100% FC, 75% FC, and 50% FC) and four Se application rates (0 ppm, 30 ppm, 60 ppm, and 90 ppm). This research aimed to investigate the effect of exogenously applied Se on morpho-physiological and biochemical attributes of sunflower to improve the drought tolerance. Foliar Se application significantly lowered H2O2 (hydrogen peroxide; ROS) (20.89%) accumulation that markedly improved glycine betaine (GB) (74.46%) and total soluble protein (Pro) (68.63%), improved the accumulation of ascorbic acid (AA) (25.51%), total phenolics (TP) (39.34%), flavonoids (Flv) (73.16%), and anthocyanin (Ant) (83.73%), and improved the activity of antioxidant system superoxide dismutase (SOD) (157.63%), peroxidase (POD) (100.20%), and catalase (CAT) (49.87%), which ultimately improved sunflower growth by 36.65% during drought stress. Supplemental Se significantly increased shoot Se content (93.86%) and improved calcium (Ca2+), potassium (K+), and sodium (Na+) ions in roots by 36.16%, 42.68%, and 63.40%, respectively. Seleniumsupplements at lower concentrations (60 and 90 ppm) promoted the growth, development, and biochemical attributes of sunflowers in controlled and water-deficient circumstances. However, selenium treatment improved photosynthetic efficiency, plant growth, enzymatic activities, osmoregulation, biochemical characteristics, and nutrient balance. The mechanisms and molecular processes through which Se induces these modifications need further investigation to be properly identified. [ABSTRACT FROM AUTHOR]

The quality of river and borehole water fluctuates because of both agricultural and industrial pollutants. Surface runoff during the rainy seasons is high which promote increased turbidity levels in water sources, and this exerts pressure on the quality and usability of the water for domestic use. Unfortunately, most municipalities in developing countries are poor to afford conventional water treatment methods. This study assessed the use of natural coagulants extracted from sunflower seeds for turbidity treatment. Water samples were collected during summer, winter, and autumn from 10 randomly selected groundwater sources and three segments of the Mwerahari River in Buhera District, Zimbabwe. Results captured seasonal turbidity variations across the river segments and the boreholes. Summer season recorded the maximum average levels of turbidity (76 NTU) while autumn and winter recorded 38.7 NTU 36.7 NTU, respectively. Water turbidity levels were above the acceptable 5 NTU Standard Association of Zimbabwe and WHO. The maximum removal efficiency of turbidity was achieved at 80 min at the dose of 4 g/l. These results revealed that the removal efficiency of 95% with 4.6 NTU turbidity is a function of dose; removal efficiency increases as dose of coagulant increases. These results demonstrated that sunflower seed is an effective low-cost natural coagulant for turbidity water treatment. [ABSTRACT FROM AUTHOR]

Sunflower (Helianthus annuus L.), a vital crop for global vegetable oil production, encounters sustainability challenges in its cultivation. This study assesses the effects of incorporating a winter cover crop (CC), Avena sativa (L.), on the subsequent growth of sunflower crops and the vitality of their rhizosphere microbial communities over a two-year period. It examines the impact of two methods for suppressing winter CC--chemical suppression using glyphosate and mechanical suppression via rolling--both with and without the addition of phosphorus (P) starter fertilizer. These approaches are evaluated in comparison to the regional best management practices for sunflower cultivation, which involve a preparatory chemical fallow period and the subsequent application of starter P fertilizer. The methodology utilized Illumina sequencing for the analysis of rhizosphere bacterial 16S rRNA genes and fungal internal transcribed spacer (ITS) amplicons. Findings indicate a significant improvement (9-37%) in sunflower growth parameters (plant height, stem diameter, head diameter, and head dry weight) when cultivated after glyphosate-suppressed winter CC compared to the chemical fallows. Conversely, rolling of winter CC generally negatively affected sunflower growth. Rhizosphere bacterial communities following chemical suppression of winter CC showed greater Pielou's evenness, indicating a uniform distribution of species. In general, this treatment had more detrimental effects on beneficial sunflower rhizosphere bacteria such as Hymenobacter and Pseudarthrobacter than rolling of the winter CC, suggesting that the overall effect on sunflower growth may be mitigated by the redundancy within the bacterial community. As for fungal diversity, measured by the Chao-1 index, it increased in sunflowers planted after winter CC and receiving P fertilization, underscoring nutrient management's role in microbial community structure. Significant positive correlations between fungal diversity and sunflower growth parameters at the reproductive stage were observed (r = 0.41-0.72; p < 0.05), highlighting the role of fungal communities in plant fitness. The study underscores the positive effects of winter CC inclusion and management for enhancing sunflower cultivation while promoting beneficial microbes in the crop's rhizosphere. We advocate for strategic winter CC species selection, optimization of mechanical suppression techniques, and tailored phosphorus fertilization of sunflower to foster sustainable agriculture. [ABSTRACT FROM AUTHOR]

From the Archaic period onward, Indigenous populations across the Eastern Woodlands cultivated a suite of crops known to archaeologists as the Eastern Agricultural Complex. However, aside from squash (Cucurbita pepo) and sunflower (Helianthus annuus), little evidence exists for the cultivation of these plants in the northeastern Algonquian homeland. Botanical analysis from the Manna site (36Pi4), located in the Upper Delaware Valley, provides evidence for the cultivation of the full suite of Eastern Agricultural Complex crops. Flotation samples analyzed from Manna provide the first evidence for possible Lenape cultivation of chenopodium (Chenopodium berlandieri), squash, sunflower, and marshelder (Iva annua) from contexts dating to AD 0–1650 (Middle and Late Woodland) at Manna. Lenape cultivation of these crops complicates the traditional view of Indigenous agricultural systems in northeastern North America and raises questions about when and how these species were introduced to the region. [ABSTRACT FROM AUTHOR]

Summary: Vascular systems are intimately related to the shape and spatial arrangement of the plant organs they support. We investigate the largely unexplored association between spiral phyllotaxis and the vascular system in Asteraceae flower heads.We imaged heads of eight species using synchrotron‐based X‐ray micro‐computed tomography and applied original virtual reality and haptic software to explore head vasculature in three dimensions. We then constructed a computational model to infer a plausible patterning mechanism.The vascular system in the head of the model plant Gerbera hybrida is qualitatively different from those of Bellis perennis and Helianthus annuus, characterized previously. Cirsium vulgare, Craspedia globosa, Echinacea purpurea, Echinops bannaticus, and Tanacetum vulgare represent variants of the Bellis and Helianthus systems. In each species, the layout of the main strands is stereotypical, but details vary. The observed vascular patterns can be generated by a common computational model with different parameter values.In spite of the observed differences of vascular systems in heads, they may be produced by a conserved mechanism. The diversity and irregularities of vasculature stand in contrast with the relative uniformity and regularity of phyllotactic patterns, confirming that phyllotaxis in heads is not driven by the vasculature. See also the Commentary on this article by Burian & Kierzkowski, 243: 10–13. [ABSTRACT FROM AUTHOR]

Sunflower (Helianthus annuus) is an important oil crop, ranking behind soybean, peanut, and rapeseed in terms of planting area in China. Throughout its cultivation, sunflower is susceptible to various diseases that can significantly reduce its seed yield. Among them, Fusarium species pose a major threat to numerous crops. The accurate identification of Fusarium species responsible for specific diseases is crucial for developing effective control measures. In Inner Mongolia, sunflower disk rot (SDR) has been observed in various sunflower fields, with an average infection rate of approximately 8.50%. The infection rate can reach up to 11.67% in certain highly susceptible cultivars. Samples of diseased sunflower receptacles were collected from different locations, and Koch's postulates were employed to identify the causal agent. The results confirmed Fusarium verticillioides as the pathogen responsible for SDR. Fungicide toxicity tests were conducted, screening six fungicides for efficacy against F. verticillioides. Fludioxonil and Flutolanil were identified as the most effective, with EC50 values of 0.05 µg/mL (R = 0.9825) and 0.96 µg/mL (R = 0.9964), respectively. This is the first report of SDR caused by F. verticillioides, and it will alert sunflower researchers to include SDR in the disease list, so as to control sunflower diseases with integrated management strategies successfully. [ABSTRACT FROM AUTHOR]

The sunflower (Helianthus annuus L.) is one of the most essential oil crops in the world. Several component traits, including flowering time, plant height, stem diameter, seed weight, and kernel weight, determine sunflower seed and oil yield. Although the genetic mechanisms governing the variation of these yield-related traits have been studied using various approaches, genome-wide association studies (GWAS) have not been widely applied to sunflowers. In this study, a set of 342 sunflower accessions was evaluated in 2019 and 2020 using an incomplete randomized block design, and GWAS was conducted utilizing two complementary approaches: the mixed linear model (MLM) and the fixed and random model circulating probability unification (farmCPU) model by fitting 226,779 high-quality SNPs. As a result, GWAS identified a number of trait-associated SNPs. Those SNPs were located close to several genes that may serve as a basis for further molecular characterization and provide promising targets for sunflower yield improvement. [ABSTRACT FROM AUTHOR]

Purpose. To study the influence of steppe and forest-steppe climatic conditions on the yield, oil content in seeds and fatty acid composition of oil in new sunflower varieties of high oleic and oilseed use. Methods. The research was conducted in accordance with "Methods of qualification examination of plant varieties for their suitability for distribution in Ukraine (general part)" and "Methods of qualification examination of plant varieties for their suitability for distribution. Methods of determining quality indicators of plant production". The following methods were used in the research: laboratory, comparison, generalisation, mathematical statistics, analysis and synthesis to draw conclusions. Results. The fatty acid composition of the seeds of new varieties of sunflower (Helianthus annuus L.) of high oleic and oilseed use, grown in different soil and climatic conditions, was studied. According to the results of the analysis in the steppe zone, the variety 'LG50648' has the highest economic and value characteristics: oil content (51,0%), oleic acid (85.1%), yield (3.11 t/ha); varieties 'SULIANO' and 'MAS 908HOCP' - yield (3.40 and 3.91 t/ha) and oleic acid content (85.8 and 86.1%) regardless of the growing conditions. It was found that high oleic sunflower varieties 'MAS 908HOCP', 'LG50648', 'SULIANO' grown under steppe and forest-steppe conditions yielded higher quality oil. The maximum content of oleic acid in 2022-2023 was characteristic of the seeds of the varieties 'MAS 908HOCP' (86.1% in the steppe and 85.8% in the forest steppe) and 'SULIANO'. The hi ghest linoleic acid content was obtained in the seeds of the oilseed use varieties 'STK104' (62.9% in the steppe and 58.5% in the forest steppe) and 'STK103' (61.2% in the forest steppe). Among the high oleic varieties, the best results were obtained with 'LG50648' (5.7% in the steppe and 5.9% in the forest steppe). Conclusions. Oil content of sunflower varieties and fatty acid composition are determined by varietal characteristics of sunflower and environmental conditions. Modern sunflower varieties, which are included in the State Register of Plant Varieties of Ukraine, have high yield potential and can provide a large yield of vegetable oil per unit area. Agroclimatic conditions have different effects on the gross seed yield and oil quality in the conditions of the forest steppe and steppe of Ukraine. [ABSTRACT FROM AUTHOR]

Stress-associated proteins (SAPs) are known to play an important role in plant responses to abiotic stresses. This study systematically identified members of the sunflower SAP gene family using sunflower genome data. The genes of the sunflower SAP gene family were analyzed using bioinformatic methods, and gene expression was assessed through fluorescence quantification (qRT-PCR) under salt and drought stress. A comprehensive analysis was also performed on the number, structure, collinearity, and phylogeny of seven Compositae species and eight other plant SAP gene families. The sunflower genome was found to have 27 SAP genes, distributed across 14 chromosomes. The evolutionary analysis revealed that the SAP family genes could be divided into three subgroups. Notably, the annuus variety exhibited amplification of the SAP gene for Group 3. Among the Compositae species, C. morifolium demonstrated the highest number of collinearity gene pairs and the closest distance on the phylogenetic tree, suggesting relative conservation in the evolutionary process. An analysis of gene structure revealed that Group 1 exhibited the most complex gene structure, while the majority of HaSAP genes in Group 2 and Group 3 lacked introns. The promoter analysis revealed the presence of cis-acting elements related to ABA, indicating their involvement in stress responses. The expression analysis indicated the potential involvement of 10 genes (HaSAP1, HaSAP3, HaSAP8, HaSAP10, HaSAP15, HaSAP16, HaSAP21, HaSAP22, HaSAP23, and HaSAP26) in sunflower salt tolerance. The expression of these 10 genes were then examined under salt and drought stress using qRT-PCR, and the tissue-specific expression patterns of these 10 genes were also analyzed. HaSAP1, HaSAP21, and HaSAP23 exhibited consistent expression patterns under both salt and drought stress, indicating these genes play a role in both salt tolerance and drought resistance in sunflower. The findings of this study highlight the significant contribution of the SAP gene family to salt tolerance and drought resistance in sunflower. [ABSTRACT FROM AUTHOR]

The development of floral organs, crucial for the establishment of floral symmetry and morphology in higher plants, is regulated by MADS-box genes. In sunflower, the capitulum is comprised of ray and disc florets with various floral organs. In the sunflower long petal mutant (lpm), the abnormal disc (ray-like) floret possesses prolongated petals and degenerated stamens, resulting in a transformation from zygomorphic to actinomorphic symmetry. In this study, we investigated the effect of MADS-box genes on floral organs, particularly on petals, using WT and lpm plants as materials. Based on our RNA-seq data, 29 MADS-box candidate genes were identified, and their roles on floral organ development, especially in petals, were explored, by analyzing the expression levels in various tissues in WT and lpm plants through RNA-sequencing and qPCR. The results suggested that HaMADS3, HaMADS7, and HaMADS8 could regulate petal development in sunflower. High levels of HaMADS3 that relieved the inhibition of cell proliferation, together with low levels of HaMADS7 and HaMADS8, promoted petal prolongation and maintained the morphology of ray florets. In contrast, low levels of HaMADS3 and high levels of HaMADS7 and HaMADS8 repressed petal extension and maintained the morphology of disc florets. Their coordination may contribute to the differentiation of disc and ray florets in sunflower and maintain the balance between attracting pollinators and producing offspring. Meanwhile, Pearson correlation analysis between petal length and expression levels of MADS-box genes further indicated their involvement in petal prolongation. Additionally, the analysis of cis-acting elements indicated that these three MADS-box genes may regulate petal development and floral symmetry establishment by regulating the expression activity of HaCYC2c. Our findings can provide some new understanding of the molecular regulatory network of petal development and floral morphology formation, as well as the differentiation of disc and ray florets in sunflower. [ABSTRACT FROM AUTHOR]