Petal Width Research Articles

Assessment of genetic parameters and heritability of Dendrobium species section Spatulata native to Indonesia

Being one of the most abundant genera of orchids, Dendrobium presents a valuable genetic resource for hybridization programs. Morphological characterization and assessment of genetic parameters plays a crucial role in establishing genetic connections among orchid species within the same genus. The study aims to discern the morphological traits of five Indonesian Dendrobium species, intending to evaluate their potential as candidates for crossbreeding programs. The materials used in this study were D. antennatum, D. discolor, D. stratiotes, D. lineale, D. gouldii, and D. sylvanum. This research examines 21 quantitative traits and 21 qualitative morphological traits of the studied Dendrobium. The findings reveal variations in characters related to flowers, leaves, and pseudobulbs. The analysis of genetic parameters indicates the presence of genetic diversity in traits such as flower stalk length, length of inflorescence, flower series length, flower length, flower width, dorsal sepal width, lateral sepal width, petal length, petal width, labellum length, labellum width, and the number of florets. All observed traits demonstrate high heritability. So, the characters that have high genetic variability and heritability are valuable in selection criteria for plant breeding.

Cell wall remodeling confers plant architecture with distinct wall structure in Nelumbo nucifera.

Lotus (Nelumbo nucifera G.) is a perennial aquatic horticultural plant with diverse architectures. Distinct plant architecture (PA) has certain attractive and practical qualities, but its genetic morphogenesis in lotus remains elusive. In this study, we employ genome-wide association analysis (GWAS) for the seven traits of petiole length (PLL), leaf length (LL), leaf width (LW), peduncle length (PLF), flower diameter (FD), petal length (PeL), and petal width (PeW) in 301 lotus accessions. A total of 90 loci are identified to associate with these traits across 4 years of trials. Meanwhile, we perform RNA sequencing (RNA-seq) to analyze the differential expression of the gene (DEG) transcripts between large and small PA (LPA and SPA) of lotus stems (peduncles and petioles). As a result, eight key candidate genes are identified that are all primarily involved in plant cell wall remodeling significantly associated with PA traits by integrating the results of DEGs and GWAS. To verify this result, we compare the cell wall compositions and structures of LPA versus SPA in representative lotus germplasms. Intriguingly, compared with the SPA lotus, the LPA varieties have higher content of cellulose and hemicellulose, but less filling substrates of pectin and lignin. Additionally, we verified longer cellulose chains and higher cellulose crystallinity with less interference in LPA varieties. Taken together, our study illustrates how plant cell wall remodeling affects PA in lotus, shedding light on the genetic architecture of this significant ornamental trait and offering a priceless genetic resource for future genomic-enabled breeding.

Determination of natural populations to be included in breeding program in St. John's wort species (Hypericum perforatum L.).

St. John's wort (Hypericum perforatum L.) is a medicinal and aromatic plant of rapidly increasing importance. The cultural production of this species, which is of economic importance due to its medicinal properties, is limited. One of the main ways to increase production is to develop cultivars. Thus, the homogeneous raw material required for a standard product will be provided. This study aimed to determine the characteristics of natural populations to obtain productive cultivars with high hypericin and hyperforin that can meet market demands. In addition to yield and quality values, other characteristic features of the plant such as flower diameter, petal length and petal width, which directly affect productivity, were revealed in the study. The study was conducted under field conditions for two years with three replications. Fresh flower weight among the populations varied between 30.15 and 240.28 g/plant, while the hypericin ratio varied between 51.32 and 105.31 (mg/100 g). The study determined a wide variation among the populations, and the populations with superior characteristics were included in the breeding program.

Chrysanthemum lavandulifolium homolog ClCYCA2;1 modulates cell division in ray florets.

Morphology of ray florets in chrysanthemums is tightly associated with cell division and cell expansion, both of which require proper cell cycle progression. Here we identified a Chrysanthemum lavandulifolium homolog ClCYCA2;1, whose expression in ray florets is negatively correlated with petal width in C. lavandulifolium. Two TCP transcription factors in CYCLOIDEA2 (CYC2) family, ClCYC2a interacts with and stabilizes ClCYC2b and the latter can bind to the promoter of ClCYCA2;1 to activate its transcription. Overexpression of ClCYCA2;1 in C. lavandulifolium reduces the size of capitula and ray florets. Cytological analysis reveals that ClCYCA2;1 overexpression inhibits both cell division and cell expansion via repressing mitotic cell cycle in ray florets whose latitudinal development was more negatively influenced leading to increased ratios of petal length to width at later developmental stages. Yeast two hybrid library screening reveals multiple ClCYCA2;1 interacting proteins including ARP7, and silencing ClARP7 inhibits the development of ray florets. Co-immunoprecipitation assays confirm that ClCYCA2;1 can induce the degradation of ClARP7 to inhibit the development of ray florets. Taken together, our study constitutes a regulatory network containing ClCYC2b-ClCYCA2;1-ClARP7 in ray floret development via governing mitosis, which may facilitate breeding efforts targeted for novel ornamental traits of chrysanthemums.

Uncovering genes involved in pollinator-driven mating system shifts and selfing syndrome evolution in Brassica rapa.

Shifts in pollinator occurrence and their pollen transport effectiveness drive the evolution of mating systems in flowering plants. Understanding the genomic basis of these changes is essential for predicting the persistence of a species under environmental changes. We investigated the genomic changes in Brassica rapa over nine generations of pollination by hoverflies associated with rapid morphological evolution toward the selfing syndrome. We combined a genotyping-by-sequencing (GBS) approach with a genome-wide association study (GWAS) to identify candidate genes, and assessed their functional role in the observed morphological changes by studying mutations of orthologous genes in the model plant Arabidopsis thaliana. We found 31 candidate genes involved in a wide range of functions from DNA/RNA binding to transport. Our functional assessment of orthologous genes in A. thaliana revealed that two of the identified genes in B. rapa are involved in regulating the size of floral organs. We found a protein kinase superfamily protein involved in petal width, an important trait in plant attractiveness to pollinators. Moreover, we found a histone lysine methyltransferase (HKMT) associated with stamen length. Altogether, our study shows that hoverfly pollination leads to rapid evolution toward the selfing syndrome mediated by polygenic changes.

Natural selection by pollinators on floral attractive and defensive traits did not translate into selection via fruits in common milkweed

Considering both pollinator and herbivore pressures on plant reproductive and defensive traits is key to understanding patterns of selection for plants. However, phenotypic selection studies connecting floral traits and plant defenses with pollinator activity and herbivore damage remain rare. We used the common milkweed, Asclepias syriaca (Apocynaceae), to study phenotypic selection on attractive and defensive traits, and nectar rewards. We measured herbivore (leaf damage) and pollinator activity (pollinia movement) and quantified selection via female (pollinia insertions and fruit number) and male fitness (pollinia removals). We found selection to increase plant and inflorescence size and to decrease floral size (i.e. petal width) via female fitness. We also detected selection to increase floral but not leaf latex. The lack of selection on leaf latex was congruent with the low herbivory observed, however we also did not observe florivory in the population that would explain the advantage of more floral latex. Interestingly, we found selection on attractive traits differed via pollinia insertions and fruits initiated, suggesting that something other than pollinators was driving selection via fruit production. In contrast to female fitness, we did not find selection on any trait through male fitness, suggesting no sexual conflicting selection, at least through these proxies. Our findings reinforce the importance of the direct assessment of pollinator pressures in phenotypic selection studies before assuming pollinators as drivers of floral evolution by natural selection. Further work in southern populations closer to the centre of the species range, where herbivory and plant defense investment are higher, may help elucidate selection on attractive and defensive traits.

Impacts of reduced water availability on vegetative and reproductive traits of a Solanum species

AbstractWhile drought is known to affect crop yields negatively, there is limited knowledge of the strategies used by animal‐pollinated plants to cope with such conditions. In this study, we simulated low and moderate drought conditions in a greenhouse experiment and examined the vegetative and reproductive traits of a buzz‐pollinated species (Solanum lycopersicum). Our findings indicate that individuals exposed to both drought conditions decreased in height and bore fewer leaves but increased in the ratio of root length to dry mass. The number of flowers produced per day and the overall flower production were higher in plants under control conditions. We found no differences in the onset of flowering between the treatments, but the plants exposed to low drought showed peak flowering earlier. Among the morphometric traits, flower height, floral diameter, petal length, and petal width were significantly lower in both drought conditions. Individuals in the moderate‐drought treatment displayed greater variation in reproductive traits than those in the low‐drought treatment. Overall, drought stress negatively impacted the aboveground vegetative growth and the reproductive efforts of plants.

Comprehensive Classification of Iris Flower Species: A Machine Learning Approach

This study employs robust machine learning techniques to comprehensively assess the classification of Iris flower species. This study investigates the effectiveness of several machine learning algorithms in reliably classifying Iris flower species by utilizing a dataset that includes crucial morphological attributes such as sepal length, sepal width, petal length, and petal width. The algorithms under consideration are Decision Tree, Random Forest, Support Vector Machine (SVM), K-Nearest Neighbors (KNN), and XGBoost. Every algorithm has its own distinct methodology for classification, where Decision Trees offer clear interpretability and Random Forest and XGBoost offer strong and complex ensemble techniques. The primary aim of this study is to assess and contrast different algorithms, considering not only their classification accuracy but also significant performance metrics including precision, recall, F1-score, ROC AUC, and specificity. This research provides valuable insights into the capabilities and constraints of each methodology when implemented on a meticulously organized and defined botanical dataset. It is expected that the results of this study will contribute significantly to the fields of artificial intelligence and botanical taxonomy, highlighting the capacity of these methods to accurately identify and categorize plant species.

Analysis of Naive Bayesian and Back Propagation algorithms in iris classification

An efficient taxonomy of irises can provide botanists with valuable tools. Machine learning algorithms can effectively improve the performance of iris classification models because they can automatically analyze and summarize data. To this end, this paper introduces Naive Bayesian (NB) and Back Propagation (BP) to build classification models. When creating the NB model, the petal and sepal data from the iris dataset are used sequentially as classification criteria to classify the data. When constructing the BP model, the author sets different iterations and outputs the loss function and accuracy of the BP model under different iterations. The study finds that the NB model has higher classification accuracy when using petal length and petal width as classification criteria, which is 17% higher than the classification accuracy using sepal length and sepal width. Therefore, the NB model is more suitable for classifying independent data. By studying the use of the BP algorithm to classify iris flowers, the automatic classification of iris flowers can be realized and the accuracy of classification can be improved. Compared with the traditional NB algorithm, the BP algorithm can better mine the hidden patterns and information in the iris data and make effective classifications. This study provides new insights and discoveries for the taxonomic study of Iris plants.

Identification of distinct roses suitable for future breeding by phenotypic and genotypic evaluations of 192 rose germplasms

Rose (Rosa) is a prominent ornamental plant that holds substantial economic and social significance. Roses originating from different regions exhibit intricate phenotypic and genetic characteristics, but the majority of rose genetic resources are poorly characterized. In this study, 192 genotypes of the genus Rosa were examined using 33 phenotypic traits and 10 pairs of SSR markers. Compared to wild species, both old garden and modern roses exhibited a significant level of diversity, with flower color having the highest degree of diversity and style morphology having the lowest degree of diversity. This phenomenon may be attributed to the limited utilization of wild roses due to their simpler ornamental traits and the frequent phenotypic and molecular infiltration between old garden roses and modern roses. Following a inaugural comprehensive evaluation employing principal component analysis, R. chinensis ‘Zihongxiang’, R. hybrida ‘Burgundy Iceberg’, R. hybrida ‘Conrad F. Meyer’, R. rugosa ‘Gaohong’ and R. floribunda ‘Sheherazad’ were selected as core germplasm resources for future breeding. Moreover, three tetraploid roses, namely R. hybrida ‘Midnight Blue’, R. floribunda ‘Sheherazad’, and R. hybrida ‘Couture Rose Tilia’, with significant differences in both phenotypic and molecular profiles were selected and reciprocally intercrossed. Ultimately, two populations were obtained exhibiting significant variation in flower size, annual stem color, stem pickle density, and leaf number. Furthermore, our results indicated that the traits of flower diameter, flower height, petal width, and petal number may potentially be controlled by two major-effect loci. In conclusion, this study provides novel insights into the evolutionary patterns of Rosa germplasm resources. It paves the way for identifying core genotypes that carry distinct ornamental characteristics and possess immense value for breeding novel varieties in the future.

Flower morphology and sexual phenotype of Capparis ovata Desf.

It was aimed to investigate the flower morphology and sexual phenotypes of Capparis ovata Desf. A C. ovata population inhabits in Çorum Osmancık Kumbaba locality. A total of 68 flower samples were collected from the population and their morphological characteristics and sexual phenotypes were investigated. According to the morphometric data, the coefficient of variation (CV) was calculated for the examined traits. Petal width (CV:3.11-20.26%) and sepal width (CV: 3.17-20.57%) showed the highest variation range. In terms of flower phenotype, 25 out of 68 flowers (36.76%) showed perfect flower and 43 (63.24%) showed male flower phenotype. The perfect flowers are hypogeynous flowers and have campylotropous type ovules. C. ovata has zygomorphic flower. C. ovata Desf. plants were defined as andromonoecious due to both the male flower and the perfect flower are present on the same plant. In conclusion, according to morphological analysis, a remarkably high variation was observed in flower morphological structures and the ratio of male flowers were found to be more common than perfect flowers in the C. ovata Desf. population. During evolutionary history, the protandry feature, in which male and female reproductive organs begin to develop at different times in perfect flowers, emerged in plants to prevent the depression of self-pollination, and inbreeding.

Determining Salt Tolerance of Zinnia Flower

In this study, it was aimed to determine the effects of irrigation water containing different salt levels on the morphological characteristics of zinnia (Zinnia elegans). For this purpose, five different salt levels (control, 2 dS m-1, 4 dS m-1, 6 dS m-1 and 8 dS m-1) were established. As morphological characteristics, plant height, plant diameter, number of flowers, flower diameter, flower stalk length, flower stalk diameter, petal number, petal length, petal width, leaf thickness, leaf length and leaf width were measured. Irrigation was carried out at 7-day intervals. Soil moisture was monitored with pot weights. The research was carried out in Çanakkale Onsekiz Mart University, Faculty of Agriculture, in 2020.
 As a result of the study, while the number of flowers, flower diameter, number of petals, leaf thickness, leaf length and leaf width values of morphological features were found to be statistically different according to salt levels; plant height, plant diameter, peduncle length, peduncle diameter, petal length and petal width were found to be insignificant. When evaluated in terms of visuality, it can be said that there are significant differences between the treaments depending on the level of salt stress. According to the results of the research, it was revealed that the salt tolerance of the zinnia flower was partially low.

More is not always better: Impact of nutrient-addition on floral traits important for buzz pollination

Nutrient addition can affect plant fitness by altering resource allocation to reproduction or modifying floral traits. Alterations in floral attributes, particularly in species that exhibit specialization in specific ecological niches, can disrupt or augment the dynamics of interactions between plants and their pollinators. However, very little is known about how soil enrichment affects the floral characteristics and pollen release dynamics of buzz pollinated plants. Our study analyzed the effects of nutrient enrichment on the reproductive traits of a buzz pollinated plant species. Under greenhouse conditions, we established a phosphorus-rich nutrient gradient to investigate the impact of such enrichment on tomato plants (Solanum lycopersicum). Our study focused on: i) flowering patterns, ii) flower morphology, iii) pollen release from anthers, and iv) pollen quantity and quality (protein concentration). Plants were grown in low, intermediate, and high nutrient conditions, and various functional traits that are essential for buzz pollination were examined. Adding nutrients improved the display of flowers. Morphometric traits important for pollinator attraction and interaction, such as floral diameter, anther-tube width, and petal width, showed an increase in the high nutrient condition. The pollen quality and quantity were found to be unaltered; however, flowers originating from intermediate and high nutrient conditions exhibited reduced pollen release upon buzzing despite possessing ample pollen reserves. Our findings suggest that the positive effects of nutrient addition on floral traits are limited to a narrow range of concentrations. Higher concentrations can diminish these effects and impact the accessibility of pollen, as well as the reproductive performance of plants. In conclusion, based on our results, we predict that changing land use scenarios leading to nutrient accumulation may have significant consequences for plant-pollinator interactions.

Molecular phylogeny and character-mapping support the synonymy of Cordobia and Gallardoa in Mionandra (Malpighiaceae)

Background and aims – Cordobia, Gallardoa, Mionandra, and Peixotoa (Stigmaphylloid clade, Malpighiaceae) are four small, closely related genera comprising shrubs or lianas endemic to South American savannas, dry forests, and temperate steppes. Their generic limits have significantly changed in the last century, and past molecular phylogenetic studies of Malpighiaceae have not tested the morphological characters of this group to identify synapomorphies supporting these clades/genera. Material and methods – We sampled the monospecific Cordobia and Gallardoa, one species of Mionandra (out of 2 spp.), nine species of Peixotoa (out of 29 spp.), and a single species of Camarea and Janusia as outgroups. Bayesian and Maximum Likelihood analyses were carried out for this clade based on five molecular markers (i.e. ETS, ITS, PHYC, matK, and ndhF). A set of 16 macromorphological characters was scored and coded for identifying synapomorphies under the Maximum Likelihood criteria. Key results – Our molecular phylogeny recovered Peixotoa as monophyletic and sister to the clade comprising Cordobia + Gallardoa + Mionandra, strongly corroborating previous phylogenetic studies of Malpighiaceae. The character-mapping analyses recovered two synapomorphies supporting the Cordobia + Gallardoa + Mionandra + Peixotoa clade, six supporting Mionandra s.l. (i.e. Cordobia + Gallardoa + Mionandra), and five supporting Peixotoa. Cordobia and Gallardoa are proposed as synonyms of Mionandra, alongside the necessary combinations, typifications, and identification keys. Conclusions – Morphological characters related to the degree of connation of the stipules, leaf indumentum type, petiole length, inflorescence architecture, number of flowers per inflorescence, presence of a peduncle in the 1-flowered cincinni, sepal connation, posture and texture, petal width and margin integrity, staminode presence, shape and size, and the shape of the apex of styles were key in circumscribing these lineages. Mionandra s.l. is proposed and characterised, including a new combination, an identification key to distinguish its species, a distribution map, and taxonomy notes.

Morphological characterization and screening of Impatiens wild species for heat tolerance

Impatiens sp. is an annual plant that flowers all year round. High temperature stress is a major challenge limiting crop productivity. The research was conducted at experiment garden in Palasari Cipanas, BRIN, Indonesia, at an altitude of 1000 ASL, from January - April 2023. The aim of the research was to explore the morphological variation of Impatiens wild species and to obtain some heat tolerance accession for next breeding program. Twenty nine accession of Impatiens were observed for the qualitative and quantitative data including the evaluation of heat tolerance. Twelve qualitative characters were recorded. The qualitative characters were analyzed as degree of similarity. DICE Similarity coefficient of qualitative data was 0.06. Broad variability in the genotypic, phenotypic variances and genetic advance was found for leaf length, leaf width and heat tolerance score. Of the electrolyte leakage analyses, it was found that flower length, ventral petal length width, lateral petal length and spur length positively support the high tolerance of Impatiens accession to heat stress. The darker color of the stem, anther, and bract is followed by a reduction in the dimension of flower width, lateral petal width, dorsal petal width and spur length but the increased leaf thicknesses. There was no direct correlation between the heat tolerance score and the leaf thickness. The largest data diversity explained by 3 factors with a total variance of 68.88 %.

Caracterización fenotípica en flores de Cacao (Theobroma cacao l.) en 40 híbridos experimentales en la finca experimental La Represa

Pollination is one of the most decisive practices in cocoa cultivation; therefore, to determine the self-compatibility and evaluate the morphology of the flower, it was carried out in the experimental farm "La Represa", Quevedo, Ecuador. For this purpose, a completely randomized DCA design was used, with forty treatments, considering treatments the cocoa hybrids used, with three repetitions. Tukey's multiple range test (P≤0.05) was applied to determine the differences between the means. Manual pollination tests were performed to determine the percentage of fertilization with fifteen flowers per treatment, whose pollination rate stood out in the T26 and T38 treatments with 100% self-compatibility, followed by T15 and T35 with 80% anti-incompatibility. Variables such as the length and width of sepal and petal, peduncle length, length of staminoid and pistil, and the weight of the flower were also recorded where different hybrids stood out, such as T1 and T11 for sepal length and width with 2.70 and 8.20 mm respectively. In the height and width of the petal, the T10 and T26 treatments stood out with 2.50 mm. In the size of the peduncle, I highlight the T20 with 1.81 mm and T6 with 6.20 mm for the length of the staminoid. The length of the pistil, the T10, obtained the highest index at 2.50 mm. However, the weight of the flower highlighted the T13 and T20 treatments, registering the highest average with 0.065 g, concerning the other hybrids studied. Keywords: Autocompatibility, cocoa , hybrids , pollination ; flowers .

Assessment of relationship among traits and genotypes for melon (Cucumis melo) breeding

Abstract. Maghfiroh RN, Suwarno WB, Sobir, Gunawan E. 2023. Assessment of relationship among traits and genotypes for melon (Cucumis melo) breeding. Biodiversitas 24: 4523-4531. Melon (Cucumis melo L.) is widely consumed as fresh fruit or juice, and therefore deeper analyses of fruit quality are needed for future breeding purposes. Breeders have a role in providing improved melon varieties that suit consumer ideotypes or preferences. This study aimed to (i) evaluate the performance of melon genotypes, (ii) estimate the correlation between quantitative traits, and (iii) determine the clustering among genotypes based on plant and fruit traits. This research evaluated 24 genotypes from inodorus, reticulatus, and makuwa groups that were carried out from March to June 2022 at a greenhouse in the Tajur experimental station of the Center for Tropical Horticulture Studies, Bogor, Indonesia. IPB HD 2-111 and IPB HD 2-100 had good quality based on soluble solids content, fruit shape, flesh texture, and rind color, and G30 was relatively superior on flesh thickness, fruit weight, and vitamin C. Based on the multiple regression analysis, it was known that petal width, petiole length, and days to harvest were significantly affected the proportion of fruit cavity width to the fruit diameter. The adjusted coefficient of determination (R2) was 0.569. Cluster analysis grouped 23 genotypes into three main clusters based on the neighbor-joining method. These results may be useful for selection in melon breeding programs.

A Novel Method Using the Petal Pattern for Contouring a Domed Nipple in Tuberous Breasts.

The main cause of domed nipples is increased pressure, which causes the breast tissue to herniate toward the nipple-areola complex. It appears as a characteristic of a tuberous breast rather than occurring alone, and the boundary between the nipple and areolar region is unclear. The authors present a method using petal patterns for single-stage aesthetic correction of domed nipples. The method is designed by placing the left and right corners of each petal at the desired position as the edge boundary of the nipple. The number and width of petals are adjusted so that the obtuse angle between the nipple and areola is 90 to 100 degrees. The areolar and soft tissues in the designed patterns are excised together with the skin and collected using a barbed suture in a specially designed suture technique. Surgery is completed after the skin is sutured using nylon. Case examples are presented to illustrate the appropriate candidate selection and results. Overall, the aesthetic results are positive in terms of shape and patient satisfaction. This method is useful for contouring domed nipples. This new design is simple, leaves minimal scars, and provides the surgeon with an additional option for treating tuberous breasts. It can be used alone or along with breast augmentation.

Karakteristik Buah dan Biji Lontar (Borassus Flabelifer L.)

The purpose of this study was to provide the data about character of lontar fruit and seeds in Kefamenanu City, North Central Timor Regency. This research was conducted from August to September 2022 using exploration and sample collection methods than contnued with characterization of fruit and seed. The results showed that the lontar fruit and seed in Kefamenanu can be characterized using the characteristics of the diameter of the base of the petals, the diameter of the tip of the petals, the length of the inner petals, the length of the outer petals, the width of the inner petals, the width of the outer petals, the number of petals, color. petals, edges of petals, petal shape, weight of petals, weight of fruit with petals, weight of fruit without petals, fruit diameter, fruit length, fruit circumference, fruit skin color, fruit shape, fruit skin surface, fruit tip and base surface, base color and fruit tip, seed weight, seed length, seed width, seed diameter, endosperm diameter, seed coat thickness, endosperm length, and endoperm color. In conclusion, there are 31 qualitative and quantitative characters that have been used to characterize lontar fruit and seed in Kefamenanu City.
 Keywords: Fruit and Seed Characters, Lontar

In Situ Synthesis of Hierarchical Flower-like Sn/SnO2 Heterogeneous Structure for Ethanol GAS Detection.

In this study, morphogenetic-based Sn/SnO2 graded-structure composites were created by synthesizing two-dimensional SnO sheets using a hydrothermal technique, self-assembling into flower-like structures with an average petal width of roughly 3 um. The morphology and structure of the as-synthesized samples were characterized by utilizing SEM, XRD, XPS, etc. The gas-sensing characteristics of gas sensors based on the flower-like Sn/SnO2 were thoroughly researched. The sensor displayed exceptional selectivity, a rapid response time of 4 s, and an ultrahigh response at 250 °C (Ra/Rg = 17.46). The excellent and enhanced ethanol-gas-sensing properties were mainly owing to the three-dimensional structure and the rise in the Schottky barrier caused by the in situ production of tin particles.