Flower Position Research Articles

Flower position within plants influences reproductive success both directly and via phenology.

In plants, within-individual trait variation might result from mechanisms related to ontogenetic contingency, i.e., to the position of a particular structure within the plant, previous developmental events, and/or the developmental environment. Flower position within inflorescences as well as inflorescence position within plants can influence resource provisioning, phenology, biotic interactions, and reproductive success. Despite the potential implications of within-individual variation in plant reproductive phenotypes, its causes and effects on reproductive success are still little explored. We assessed how reproductive success, in terms of fruit and seed set, and seed predation of 5883 flowers in Lathyrus vernus were influenced by their position within and among racemes, to what extent relationships between flower position and reproductive success and seed predation were mediated by phenology, and if positional effects on reproductive success depended on the external environment. In three years, basal flowers and racemes opened earlier and had higher fruit set than distal. Basal flowers also experienced higher seed predation. Differences among racemes in fruit and seed set were largely related to phenology, while differences in fruit set, seed set, and seed predation within racemes were not. In one year, differences in fruit set among flowers at different positions depended on flowering duration. Our results highlight the important role of ontogenetic contingency for within-individual variation in phenology and reproductive success. As the spatial distribution of reproductive structures affects both within-plant trait distributions and fitness, it is a likely target for natural selection.

Karakterisasi Morfologi Sukun (Artocarpus altilis Forb.) Di Desa Ohoitahit Dan Danar Kepulauan Kei Kecil Kabupaten Maluku Tenggara

This study aims to characterize the morphology of breadfruit (Artocarpus Altilis Forb.) In Ohoitahit Village and Danar Kecil Kecil Kecil Southeast Maluku. The sampling method through two sample units, namely key informants and target plant accessions. Key informants are community leaders who have in -depth knowledge about the genetic diversity of breadfruit in the village that is used as a sample. Target plant accessions are a variety of varieties of identification of key informants. Withdrawal of samples for critical informants is carried out by snowball sampling methods, while target plant accessions are selected using accidental sampling methods (accidental sampling) or intentional sampling (purposive sampling). Data presentation using descriptive methods. The results showed a significant morphological diversity in breadfruit in the Kei Islands. There is a diversity of morphology in breadfruit based on 31 observation variables. In the character of the tree, there is diversity, among others, the tree's shape, the trunk's surface, the branching pattern, and the direction of growing. In the leaf character there is diversity, namely the color of the leaf, the tip of the leaf, the length of the leaf strands, and the width of the leaf strands, and on the tip of the leaf. Flower characters have a diversity that is, the color of male flowers, male flower positions, and female flower positions. Fruit character has diversity is the shape of the fruit, the texture of the fruit skin, the sap on the skin, the skin color of the fruit, the length of the fruit, the weight of the fruit, and the fruit yield.

Floral Biology of Chinar (Platanus orientalis L.) under Temperate Conditions in the Kashmir Himalayas

Chinar, Platanus orientalis is a huge, widely distributed, and long-lived deciduous tree native to the eastern Mediterranean. It is the only species of the Platanaceae family found in India and grows throughout the valley. Since ancient times, this particular species has garnered fascination and reverence, leading to its continuous examination and admiration. However, the information related to its floral biology is meagre. The floral biology of P. orientalis is crucial to understanding its reproductive mechanisms and ecological interactions. The present study, therefore, aimed at investigating the floral characteristics of P. orientalis. For this study, seven young sexually mature trees were selected to study the floral characteristics. It was revealed that, in general, male flowers often emerge earlier than female blosssoms. The position of the male flower is always proximal and that of the female flower is distal when present on terminal branches. The average male female ratio recorded was 7:1 and the ratio between pollen and ovules on average was 9550 to 1. The pollen-ovule ratio is a fundamental reproductive parameter that provides insights into the reproductive strategies and ecological adaptations of plant species. The floral biology of P. orientalis demonstrates its adaptation to wind pollination and efficient seed dispersal mechanisms. This knowledge enhances comprehension and aids in gaining a deeper understanding of the reproductive strategies of P. orientalis and its ecological significance within its native range. Research in this field can help in developing effective conservation strategies and utilizing this species for research purposes.

Modeling Positions and Orientations of Cantaloupe Flowers for Automatic Pollination

An automatic system for cantaloupe flower pollination in greenhouses is proposed to meet the requirements of automatic pollination. The system consists of a mobile platform, robotic manipulator, and camera that reaches the flowers to detect and recognise their external features. The main task of the vision system is to detect the position and orientation of the flower in Cartesian coordinates, allowing the manipulator to reach the pose and perform pollination. A comprehensive method to ensure the accuracy of the pollination process is proposed that accurately determines the position and orientation of cantaloupe flowers in real environments. The vision system is used to capture images, detect the flower, and recognise its state according to its external features, such as size, colour, and shape, thereby providing appropriate nozzle access during pollination. The proposed approach begins with a segmentation method designed to precisely locate and segment the target cantaloupe flowers. Subsequently, a mathematical model is used to determine the key points that are important for establishing the growth orientation of each flower. Finally, an inverse-projection method is employed to convert the position of the flower from a two-dimensional (2D) image into a three-dimensional (3D) space, providing the necessary position for the pollination robot. The experimental process is conducted in a laboratory and proves the efficacy of the cantaloupe flower segmentation method, yielding precision, recall, and F1 scores of 87.91%, 90.76%, and 89.31%, respectively. Furthermore, the accuracy of the growth-orientation prediction method reaches approximately 86.7%. Notably, positional errors in 3D space predominantly fall within the allowable range, resulting in a successful pollination rate of up to 83.1%.

The patterns of inbreeding depression in food-deceptive Dactylorhiza orchids.

Inbreeding depression (ID) in food-deceptive plants have been reported previously, however, it has not been often proven that selfed seeds germinate better than outbred ones or that selfing affects ID. To resolved these issues, food-deceptive related Dactylorhiza majalis, D. incarnata var. incarnata and D. fuchsii orchids were investigated. Hand pollination treatments and control pollination were conducted. Fruit set, number of seeds per fruit, seed length, number of well-developed seeds per fruit, and proportion of in vitro asymbiotic germination seeds, were analyzed in relation to inflorescence levels and used as fitness indicators for these orchids. The ID and pollen limitation were measured. The lowest ID (δ = -1.000) was in D. majalis, and present in combination with a high pollen limitation in its populations. D. fuchsii showed higher ID (δ = 0.366), and D. incarnata var. incarnata weak ID (δ = 0.065), although ID varied between its fitness components. The seed number per fruit differed significantly between the treatments and the inflorescence levels in treatments. This study emphasizes that the breeding system rather than the flower position on the inflorescence shaped the quality and quantity of reproductive output. The ID and its effect on germination of food-deceptive orchid seeds undoubtedly played an important role.

Potential of peppers of the genus Capsicum and their use as an ornamental plant

Capsicum is a genus of the Solanaceae family, where the different types of domesticated peppers are found. They are bushy plants, originating from the Americas, producing fruits that are generally used in cooking. The Garden of the School of Agronomy, at the Federal University of Goiás, has a collection of peppers with 167 accessions, where part of these accessions (57) was evaluated to verify their suitability as an ornamental plant. This work was carried out in the experimental area of the Garden of the School of Agronomy at the Federal University of Goiás, in Goiânia – GO Brazil, in the Horticulture sector. The experiment was installed in August 2022 with sowing carried out in resistant plastic trays, with 50 cells, kept in a greenhouse and transplanting carried out in the open area. 5 (five) seedlings were used per accession, where for every 10 (ten accessions of the collection, 5 (five) seedlings of round potted commercial red pepper were transplanted, also added to the collection, with the code (UFGMH070) and the experiment outlined in enlarged blocks. The studied accessions were characterized agronomically, using fifteen descriptors recommended by IPGRI (1995). Among these descriptors, eight are quantitative in nature (plant height (PH), crown diameter (CD), fruit length (FRL), fruit width (FRW), pericarp thickness (PT), number of locules (NL), pericarp weight (PW) and seed weight (SEW) and seven have a qualitative nature (flower color (FLC), position fruit size (FRP), fruit color (FRC), fruit shape (FRS), fruit surface (FRS), seed color (SEC), seed surface (SES). For data analysis, a matrix was estimated of dissimilarity, through the joint analysis of quantitative and qualitative variables, with this matrix, a dendrogram was obtained. The grouping of accesses was obtained using the UPGMA (Unweighted Pair-Group Method Using an Arithmetic Average) method. The data were analyzed by the computational software R. To establish the ornamental value of the plants, the criteria of the Veiling cooperative in Holambra were used, where the variables plant height and position of flowers and fruits, among the descriptors evaluated, are the most important. According to the cluster analysis, there was a division into seven groups and it was possible to observe that Group III had the highest number of accesses, 63.16%, followed by Group II with 15.79%, Group IV with 12.28%. %, Group V with 3.51% and those who were isolated, in groups with only one access Group I 1.75%, Group VI 1.75% and Group VII 1.75%, of the total accesses. Within the dendrogram, the group with the largest number of accessions is Group 3, where in this group are the plants that presented ideal plant height, white flowers and fruits with an upright arrangement, ideal characteristics for their use as an ornamental plant. Agronomic characterization, based on quantitative and qualitative descriptors, enabled an interpretation of genetic dissimilarity, which allows better targeting, for the producer, research, as well as for extension.

Predicting positions and orientations of individual kiwifruit flowers and clusters in natural environments

The positional and orientational detection of kiwifruit flower clusters in the natural environment is essential for the development of automated mechanical pollination systems. To ensure the timeliness and accuracy of this process, we propose a deep-learning-based method that predicts kiwifruit flower positions and orientations. Based on a single flower, this method effectively predicts the position and orientation of the entire cluster of flowers. First, the SOLOv2 instance segmentation model is used to locate and segment the location of the target kiwifruit flowers. Subsequently, the MobileNetV2 key point detection model is employed to detect the key points of the centre of gravity of the petal contour and the stamen part of the kiwifruit flower, and draw the orientation prediction line of the corresponding clusters. Finally, flower clusters are determined by calculating the Intersection over Union (IoU) of kiwi flowers. By taking the average of the orientation prediction line of each kiwi flower in a cluster as the entire cluster’s orientation, the method effectively generates a prediction of the said orientation. To verify the effectiveness of the proposed method, we compared and analysed the effects of SOLOv2 with the YOLOv5s, YOLOv4, and Faster-RCNN models with respect to the segmentation effect. The comparison results show that the SOLOv2 model exhibits a fast segmentation speed while maintaining a high segmentation accuracy. Verification results indicate that the SOLOv2 model has an accuracy rate of 74.2% for the detection of multi-target flowers of clustered kiwifruit from a wide perspective angle. It is therefore feasible to apply the proposed method to detect the positions and orientations of kiwi flower clusters in real time. This study can provide a technical reference for the development of robotic arms for the purpose of kiwifruit pollination.

AB-452675-3 CHARACTERISTICS OF RESIDUAL SIGNALS AFTER PULSED FIELD ABLATION OF THE PULMONARY VEINS

Pulsed field ablation (PFA) is a new energy source for isolation of the pulmonary veins in the treatment of paroxysmal atrial fibrillation (PAF). Dose titration is challenging but important to avoid reversible electroporation. Analysis of high resolution unipolar electrograms after PFA might be of value to analyze the tissue response to PFA deliveries. Unipolar and bipolar electrograms were recorded from a proprietary pentaspline basket catheter (Boston Scientific Inc., USA) before and after PFA energy delivery using a novel electrophysiology recording system (ECGenius System, CathVision, Denmark) with resolution at a 0.05 mV level and a sampling rate of 2 KHz. Data was recorded from 12 consecutive patients diagnosed with PAF and scheduled for pulmonary vein isolation. The treatment protocol consisted of conventional PFA delivery in two baskets and two flower positions for each vein. Both unipolar and bipolar signals were analyzed manually. Overall, 790 EGMs from 12 patients were analyzed. In 131 out of 160 EGMs (82%) recorded after first PFA delivery, we observed a residual sharp downward deflection in the unipolar signal that matched the timing of the corresponding bipolar signal (Fig. 1). Median amplitude of the deflection was 0.18 mV (IQR = 0.09 - 0.32 mV). The sharp deflections were eliminated with further PFA delivery in 29.7% of cases (suggesting true local activation) but persisted in 71.3%. High resolution electrogram recording allows identification of residual sharp deflections in the unipolar electrogram after PFA delivery. The coincident timing with the bipolar EGM together with elimination by further PFA suggests that this EGM signature reflects true local activity. It remains to be seen whether persisting deflections are a measure for non-isolation or reversible electroporation.

Effects of floral traits on geitonogamous selfing rates and reproductive success in a protandrous species

Abstract Through its role in regulating pollinator behavior, floral display size and nectar gradient within inflorescences may alter the extent of geitonogamy and thus female reproductive success in protandrous species. However, this has seldom been examined. By quantifying selfing rate, seed number and male donor number, we estimated the effects of floral display size, nectar gradient and their interactions on plant reproduction in protandrous Aconitum gymnandrum. At plant level, selfing rate and seed number increased with a larger floral display of both main and lateral inflorescences but reduced with a declining nectar gradient. The effects of floral display of the main inflorescence on selfing rate and seed number were altered by the nectar gradient and floral display of lateral inflorescences as shown by their interactions. Larger floral display of the main inflorescence reduced male donor diversity. At flower level, the selfing rate and the seed number varied among flower positions, in which bottom flowers had lower selfing rate and higher seed number than top flowers. The effects of floral traits on geitonogamous selfing rate and seed number were inconsistent among flower positions. Although low cost of geitonogamous selfing for reproduction was tested by hand-pollination, the selfing rate was negatively correlated with seed number and male donor number in open-pollinated population. Our results suggest the potential role of trade-off between geitonogamy cost and reproductive benefit in evolution of floral traits. The variation of selfing rate and reproductive success among flowers may alter the trade-off and thus complicate evolution of traits.

The effect of inflorescence display size and flower position on pollination success in two deceptive and one rewarding orchid.

Inflorescence display size and flower position on the inflorescence play important roles in plant reproduction, in the formation of fruits and are primarily linked to pollinator behaviour. We used three orchids to determine how visitation rates and choice of pollinator depend on number and position of the flowers along the inflorescence. We measured reproductive success in (1) natural conditions, (2) hand-pollination experiments and (3) an experimental design, by modifying composition of inflorescences in populations of two deceptive orchids, Orchis anthropophora and O. italica, and one rewarding orchid, Anacamptis coriophora subsp. fragrans. There were no differences in natural fruit production in relation to flower position on the inflorescence (i.e. upper versus lower part), suggesting no preference of pollinators for different parts of the inflorescence. Hand-pollination experiments highlighted low pollen limitation in A. coriophora subsp. fragrans but high limitation in O. italica and O. anthropophora. Reproductive success of deceptive orchids in experimental plots decreased significantly when flowers on the upper half of the inflorescence were removed leading to reduced floral display, while reproductive success of the nectariferous species did not differ significantly. Our data highlight that in the examined orchids there is no clear relationship between fruit formation and flower position along inflorescences. Thus we can affirm that, for orchids, the entire inflorescence plays a dominant role in insect attraction but the part of the flower spike does not influence the choice of the insect. This implies that all flowers have the same possibility of receiving visits from pollinators, and therefore each flower has the same opportunity to set fruit.

Exploring agro-morphological diversity of Algerian hot pepper (Capsicum annuum L.) accessions using multivariate statistics

Pepper is an inevitable constituent in the diets of Algerian population. Unfortunately, the local landraces are endangered by both genetic erosion and pollution. This study aimed to perform agro-morphological characterization of hot peppers (Capsicum annuum L.) accessions. Twenty one accessions collected from the east and south of Algeria were evaluated for 24 quantitative and 38 qualitative morphological characters under green-house conditions. The trial was conducted in a Randomized Complete Block Design (RCBD), with four replicates at the experimental station of the Department of agronomical sciences of Biskra University in Southeast Algeria. Significant variations in most of the traits were strikingly demonstrated using variance analysis and coefficients of variation and the number of modalities, frequencies and Shannon–Weaver diversity index (H′) values for the quantitative and qualitative characters respectively indicating the heterogeneity of the studied accessions. The correlations between the studied quantitative variables showed that the yield parameters were correlated with the variables related to the vegetative part of the plant. The first five PCs explained 76.877 % of the total variation and identified the most discriminant variables related particularly to yield and fruit characteristics contributing to PC1: fruit width; fruit index; fruit weight, number of locules; placenta length, pedicel length, anther length, leaf width and plant height /stem length ratio. For several qualitative traits, an important degree of variability was observed. The first factorial dimension explained 42.5% of the variance and was mostly associated with: plant height; growth habit; flower position; corolla shape; number of flower per axil and fruit shape at pedicel attachment and at blossom end; calyx margin. Cluster analysis of the combined data grouped the pepper landraces into four clusters regardless of the localities and the closest accessions belonged to different localities and/or provinces. This study notably confirms the presence of considerable genetic diversity within and between accessions of hot pepper in Algeria and provides a basis for its active conservation and future selection to develop improved local pepper populations

Impacts of Different Light Spectra on CBD, CBDA and Terpene Concentrations in Relation to the Flower Positions of Different Cannabis Sativa L. Strains.

Cannabis is one of the oldest cultivated plants, but plant breeding and cultivation are restricted by country-specific regulations. The plant has gained interest due to its medically important secondary metabolites, cannabinoids and terpenes. Besides biotic and abiotic stress factors, secondary metabolism can be manipulated by changing light quality and intensity. In this study, three morphologically different cannabis strains were grown in a greenhouse experiment under three different light spectra with three real light repetitions. The chosen light sources were as follows: a CHD Agro 400 ceramic metal-halide lamp with a sun-like broad spectrum and an R:FR ratio of 2.8, and two LED lamps, a Solray (SOL) and an AP67, with R:FR ratios of 13.49 and 4, respectively. The results of the study indicated that the considered light spectra significantly influenced CBDA and terpene concentrations in the plants. In addition to the different light spectra, the distributions of secondary metabolites were influenced by flower positions. The distributions varied between strains and indicated interactions between morphology and the chosen light spectra. Thus, the results demonstrate that secondary metabolism can be artificially manipulated by the choice of light spectrum, illuminant and intensity. Furthermore, the data imply that, besides the cannabis strain selected, flower position can have an impact on the medicinal potencies and concentrations of secondary metabolites.

Qualitative Characters Diversity of Prentul Kediri Cayenne Pepper Mutant (M1) Resulted from Gamma Ray Mutation Induction

Prentul Kediri cayenne pepper is a local variety that has the potential to be developed into a new superior variety through the breeding of gamma-ray mutations. The purpose of the study is to find out the diversity and degree of similarity in plants of the M1 generation based on qualitative character. The research was conducted in August 2021-February 2022 at the research field, Ketindan Village, Malang City. This study was conducted in a completely randomized block design with three replications. Data was subjected to cluster analysis using the NTSYSpc.2.02i program. The results showed that induction of gamma-ray mutations led to phenotype diversity in several qualitative characters, namely plant habitus, leaf shapes, and fruit shapes, while two other characters, i.e., fruit calyx and the position of flowers remained uniform. The degree of intermutants at each dose of gamma ray mutation is varied. Qualitative characters that remained uniform in the mutant population (M1) were the calyx character of the fruit and the position. In the mutant population (M1), the results of mutations in gamma rays at doses of 100 Gy and 200 Gy were still found in individuals with characters 100% similar to control plants. Meanwhile, in the mutant population (M1), the results of mutations in gamma rays at a dose of 300 Gy were not found to have individuals with characters 100% similar to control plants. Keywords: Gamma ray, Mutation diversity, Prentul Kediri Cayenne Pepper

Identification and characterization of putative targets of VEGETATIVE1/FULc, a key regulator of development of the compound inflorescence in pea and related legumes.

Inflorescence architecture contributes to essential plant traits. It determines plant shape, contributing to morphological diversity, and also determines the position and number of flowers and fruits produced by the plant, thus influencing seed yield. Most legumes have compound inflorescences, where flowers are produced in secondary inflorescences (I2), formed at the flanks of the main primary inflorescence (I1), in contrast to simple inflorescences of plants like Arabidopsis, in which flowers are directly formed on the I1. The pea VEGETATIVE1/FULc (VEG1) gene, and its homologs in other legumes, specify the formation of the I2 meristem, a function apparently restricted to legumes. To understand the control of I2 development, it is important to identify the genes working downstream of VEG1. In this study, we adopted a novel strategy to identify genes expressed in the I2 meristem, as potential regulatory targets of VEG1. To identify pea I2-meristem genes, we compared the transcriptomes of inflorescence apices from wild-type and mutants affected in I2 development, such as proliferating inflorescence meristems (pim, with more I2 meristems), and veg1 and vegetative2 (both without I2 meristems). Analysis of the differentially expressed genes using Arabidopsis genome databases combined with RT-qPCR expression analysis in pea allowed the selection of genes expressed in the pea inflorescence apex. In situ hybridization of four of these genes showed that all four genes are expressed in the I2 meristem, proving our approach to identify I2-meristem genes was successful. Finally, analysis by VIGS (virus-induced gene silencing) in pea identified one gene, PsDAO1, whose silencing leads to small plants, and another gene, PsHUP54, whose silencing leads to plants with very large stubs, meaning that this gene controls the activity of the I2 meristem. PsHUP54-VIGS plants are also large and, more importantly, produce large pods with almost double the seeds as the control. Our study shows a new useful strategy to isolate I2-meristem genes and identifies a novel gene, PsHUP54, which seems to be a promising tool to improve yield in pea and in other legumes.

Mendel: From genes to genome.

Two hundred years after the birth of Gregor Mendel, it is an appropriate time to reflect on recent developments in the discipline of genetics, particularly advances relating to the prescient friar's model species, the garden pea (Pisum sativum L.). Mendel's study of seven characteristics established the laws of segregation and independent assortment. The genes underlying four of Mendel's loci (A, LE, I, and R) have been characterized at the molecular level for over a decade. However, the three remaining genes, influencing pod color (GP), pod form (V/P), and the position of flowers (FA/FAS), have remained elusive for a variety of reasons, including a lack of detail regarding the loci with which Mendel worked. Here, we discuss potential candidate genes for these characteristics, in light of recent advances in the genetic resources for pea. These advances, including the pea genome sequence and reverse-genetics techniques, have revitalized pea as an excellent model species for physiological-genetic studies. We also discuss the issues that have been raised with Mendel's results, such as the recent controversy regarding the discrete nature of the characters that Mendel chose and the perceived overly-good fit of his segregations to his hypotheses. We also consider the relevance of these controversies to his lasting contribution. Finally, we discuss the use of Mendel's classical results to teach and enthuse future generations of geneticists, not only regarding the core principles of the discipline, but also its history and the role of hypothesis testing.

Identification of the operating position and orientation of a robotic kiwifruit pollinator

Accurate identification of flower position and orientation is an essential prerequisite for robotic pollinators to accomplish precise targeted pollination and improve the pollen utilisation rate. To accurately identify the pollination position and orientation of kiwifruit flowers, this study presents a vision-based information perception approach for automatically detecting flowers and accurately identifying their positions and orientations. After using YOLO v4 to identify the kiwifruit flower, the contour detection algorithm was used to detect the contour boundary of the flower pistil area and the contour boundary of the minimum circumscribed circle of the petals, and fit the centres of gravity of the pistil contour and the petal contour according to the two contours respectively. The line connecting the two centre points was used as the central axis representing the growth direction of the flowers, achieving precise identification of the flower position and orientation. After building a robotic pollinator, an experiment was conducted to identify kiwifruit flower targets and a performance test experiment was performed to target pollinated kiwifruit flowers in a kiwifruit orchard with a mechanical arm based on flower position and orientation. The experimental results showed that the precision of the identification of kiwifruit flowers was 95.27%, the success rate of the mechanical arm for target pollination based on flower position and orientation identification was 89.59%, the average pollination time was 6 s⋅per flower, and the pollination efficiency was 20 h⋅ha-1. The identification algorithm of flower position and orientation proposed in this study can improve the precision and success rate of robotic pollination.

Genome-Wide Identification and Characterization of Members of the ACS Gene Family in Cucurbita maxima and Their Transcriptional Responses to the Specific Treatments.

Ethylene biosynthesis and signal transduction play critical roles in plant sex differentiation. ACS (1-aminocyclopropane-1-carboxylic acid synthase) is a rate-limiting enzyme in ethylene biosynthesis. However, the understanding of the ACS gene family in Cucurbita maxima is limited. Here, we identified and characterized 13 ACS genes in the C. maxima genome. All ACS genes could be divided into three groups according to a conserved serine residue at the C-terminus. Thirteen CmaACS genes were found to be randomly distributed on 10 of the 20 chromosomes of C. maxima. The ACS gene exhibits different tissue-specific expression patterns in pumpkin, and four ACS genes (CmaACS1, CmaACS4, CmaACS7, and CmaACS9) were expressed specifically in both the female and male flowers of C. maxima. In addition, the expression levels of CmaACS4 and CmaACS7 were upregulated after ethephon and IAA treatments, which ultimately increased the number of female flowers, decreased the position of the first female flower and decreased the number of bisexual flowers per plant. These results provide relevant information for determining the function of the ACS genes in C. maxima, especially for regulating the function of ethylene in sex determination.

Novel Pollination Drone for Agricultural Assistance

Abstract: One of the major issues concerning current agricultural productionis crop pollination. Approximately $74 billion per year worth of crops in rely on pollination by various pollinators. However, the recent decline ofhoney bees (i.e. colony collapse disorder) has greatly threatened productivity. Declines of other native pollinators, such as different insecttypes and animals, have also been reported. Such shortages of pollinatorshave significantly increased the cost of farmers and renting them for pollination services. To overcome this problem, this project presents an automated drone for pollination which uses deeplearning and machine learning algorithms to estimate the flower position, size, orientation, andphysical condition to guide the drone to capture and interact with flowersfor pollination. In this concept we use drone and artificial intelligence method to carry pre collected pollen and to inject them in flowers for pollination to increase productivity. Drone pollination bypasses many current issues with natural pollinators inagriculture, such as honeybee colony collapse disorder, pollinator parasites and diseases, predators, pesticide spray, adverse weather, and the availability of pollinators in a timely manner. Second, robotic pollinators will improve fruit quality andproduction. With the decreasing number of bees, artificial pollination is more in trend. If we take the example of China, 100% plants are pollinated artificially. So, we can see that artificial pollination is beneficial and can increase plant productivity. The successful completionof this project will significantly impact the field of artificial pollination inagriculture.

Directional asymmetry and direction‐giving factors: Lessons from flowers with complex symmetry

Directional asymmetry is a systematic difference between the left and right sides for structures with bilateral symmetry or a systematic differentiation among repeated parts for complex symmetry. This study explores factors that produce directional asymmetry in the flower of Iris pumila, a structure with complex symmetry that makes it possible to investigate multiple such factors simultaneously. The shapes and sizes of three types of floral organs, the falls, standards, and style branches, were quantified using the methods of geometric morphometrics. For each flower, this study recorded the compass orientations of floral organs as well as their anatomical orientations relative to the two spathes subtending each flower. To characterize directional asymmetry at the whole‐flower level, differences in the average sizes and shapes according to compass orientation and relative orientation were computed, and the left–right asymmetry was also evaluated for each individual organ. No size or shape differences within flowers were found in relation to anatomical position; this may relate to the terminal position of flowers in Iris pumila, suggesting that there may be no adaxial–abaxial polarity, which is very prominent in many other taxa. There was clear directional asymmetry of shape in relation to compass orientation, presumably driven by a consistent environmental gradient such as solar irradiance. There was also clear directional asymmetry between left and right halves of every floral organ, most likely related to the arrangement of organs in the bud. These findings indicate that different factors are acting to produce directional asymmetry at different levels. In conventional analyses not recording flower orientations, these effects would be impossible to disentangle from each other and would probably be included as part of fluctuating asymmetry.

Investigation of Bunch Cut at Different Times After Pollination and Flower Position in the Spikelet in Date Palm 'Sukkary' Variety

As many studies on other crops showed an acropetal decline of fruit-set and fruit size in the inflorescence, this paper investigates the effect of flower position in spikelets in the '˜Sukkary' variety of date palm on fruit-set and final fruit weight. Also studied was the best time to apply strand-cut (bunch cut) as an alternative to hand thinning, to increase final fruit weight. Hand thinning is a labor cost operation and worker productivity operation is one adult tree per day maximum. To study fruit-set in relation to fruit position, three types of pollen were used to pollinate female trees: new pollen harvested in March 2018, pollen stored for one year at room temperature (25-35° C), and pollen stored for two years at room temperature. Four weeks after pollination, fruits aborted and those non-aborted in every bunch were counted. Recording was done in every spikelet from proximal to distal. To study the effect of fruit position in spikelet on fruit weight, fresh pollen was used to pollinate 'Sukkary' females. Every two days, fruit weight was measured from pollination to harvest, and fruit growth pattern was drawn. An analysis of variance (ANOVA) was carried out for the final fruit weight in every spikelet part. This investigation showed no pattern in fruit-set or in final fruit weight when using new pollen. When pollinated with old pollen that was one and two years old, the proximal '˜Sukkary' flowers of the spikelets showed less fruit-set compared to those of the middle and distal part. This basipetal decline is explained by low viability of old pollen, combined with the basipetal opening of the spathes in date palm...