Corolla Diameter Research Articles

Diptera‐dominated generalist pollination systems in Eurya japonica and Eurya emarginata (Pentaphylacaceae)

AbstractWe investigated the flower visitors and floral traits of two dioecious shrub species Eurya japonica Thunb. (Pentaphylacaceae) and Eurya emarginata (Thunb.) Makino in temperate Kochi and subtropical Okinawa in Japan during the cool seasons. We demonstrated that the two Eurya species could be pollinated by a wide spectrum of flower visitors—mainly Diptera. The main pollinators were probably Chironomidae and Empididae for E. japonica in Kochi and Calliphoridae and Syrphidae for the remaining species–site combinations (i.e., E. emarginata in Kochi, E. japonica in Okinawa, and E. emarginata in Okinawa). We demonstrated that several dominant families of Dipteran visitors have the ability to pollinate the two Eurya species. Interestingly, floral traits (corolla diameter and nectar concentration) could not explain the difference in the assemblages. These results indicate that floral traits are not specifically adapted to their local pollinators. The fruit set rate was significantly lower for naturally pollinated flowers than for hand‐pollinated flowers, indicating pollen limitation in both Eurya species. However, there was no apparent difference in the number of seeds per fruit between naturally pollinated and hand‐pollinated flowers.

Taxonomic revision of Physalis species (Solanaceae) in Korea

The records of various Physalis species in Korea along with unclear descriptions and the use of multiple Korean names for a single species have led to confusion with regard to species identification in this genus. Therefore, the aim of the present study was to identify and characterize Physalis species distributed in the Republic of Korea through a literature review, specimen observations, and field surveys. Five Physalis species were found to be distributed in the Republic of Korea: P. angulata, P. lagascae, P. longifolia, P. philadelphica, and P. pubescens. Additionally, it was confirmed that part of P. fauriei and P. repens can be considered to be synonyms of P. lagascae, whereas the other part of P. fauriei is regarded as synonyms of P. pubescens. The species can be distinguished based on their life forms, presence of rhizomes, leaf serration depth, arrangement of hairs on the calyx, corolla diameter and spot color, and fruit shape and ridge number. Physalis angulata and P. pubescens are distributed in various regions, primarily in the southern and western parts of the Republic of Korea. In contrast, P. lagascae is found exclusively in limited regions of Jeju-do, Chungcheongbuk-do, and Gangwon-do, with P. longifolia and P. philadelphica found only in Yeongwol-gun of Gangwon-do. This study provides revised descriptions and an identification key along with photographs and distribution information for Physalis species in the Republic of Korea.

Insights into the bZIP gene family in Osmanthus fragrans and the role of OfbZIP98 in the callus and flower

Osmanthus fragrans has important ornamental and economic value. As the callus re-differentiation process is difficult, a genetic transformation system has not been successfully established in O. fragrans. The basic leucine zipper (bZIP) transcription factors play an important role in plant growth and development. A total of 116 OfbZIP genes were identified in O. fragrans using bioinformatics methods. According to the evolutionary relationships, these genes were divided into 12 subfamilies and were found to be unevenly distributed on 23 chromosomes of O. fragrans. The quantitative real-time PCR results showed that the expression trend of OfbZIP98 was consistent with the proliferation of O. fragrans callus. The subcellular localization and yeast self-activation results showed that OfbZIP98 was localized in the nucleus and had self-activation activity. Further, phenotypic observation of over-expressed tobacco showed that compared with the wild type (WT), the transgenic strain formed callus 4 d earlier, and callus re-differentiation began on day 15. Analysis of the callus differentiation rate showed that after 20 d of culture, the differentiation rate of the leaf callus of the transgenic strain was about twice that of the WT plants. In addition, measurements of corolla diameter, corolla circumference, corolla area, and corolla tube diameter indicated that the petals of the transgenic strain were significantly larger than the WT plants. Our results showed that OfbZIP98 has the important function of promoting callus growth, re-differentiation, and flower organ enlargement. These findings provide new insights into the potential role of OfbZIP98 in the growth and development of O. fragrans.

Study of Early Iron Age Vessels Using 3D-Modeling (Based on Baraba, Sargat Culture): Metric Characteristics

Purpose. The purpose of the paper is to approve and identify the possibilities of 3D modelling in the study of the Early Iron Age vessels.Methods. A series of experiments comparing computer and manual measurements of the vessels metric characteristics have been carried out (corolla diameter and vessel height). The experiments are based on 3D-models of three Early Iron Age vessels: a complete round-bottom vessel; a complete flat-bottom vessel; a fragmented round-bottom vessel. The respondents are represented by two groups: Iron/Bronze age and Stone Age researchers. The methods of statistics and arithmetic were used to process the results. The obtained computer and manual metric characteristics were subjected to arithmetic and statistical analyses.Results. It was revealed that the differences in measuring the corolla diameter between two groups were 0.1–1 mm. Measurements of vessels height by Stone Age researchers are more exact: the difference at the minimum discrepancies is less than 1 mm, the maximum values diverged up to 7 mm. According to the results of preliminary statistical analysis, there are no differences between the researcher groups on metric measurements of vessels. Statistical analysis showed that the results of manual measurements of simple objects (corollas) are sufficiently accurate and can be used for research. If a complex object (the complete vessel) is to be measured, it is better to use computerised measurements. Manipulation of high-precision artefact measurements is possible through the application of 3D-modelling.

Pollen and Floral Organ Morphology of 18 Oil-Tea Genotypes and Its Systematic Significance

Oil-tea belongs to the Camellia genus, an important oil crop in China. However, oil-tea is taxonomically challenging due to its morphological variation, polyploidy, and interspecific hybridization. Therefore, the present study aimed to investigate the flower organs’ morphology and pollen micro-morphology of 18 oil-tea genotypes in detail and discussed their significance for oil-tea taxonomy. The quantitative parameters of flowers were measured using Vernier caliper measurements. Pollen morphology was observed and photographed using scanning electron microscopy (SEM). The results indicated that the flower size varied significantly among the tested oil-tea genotypes, with the corolla diameter ranging from 42.25 μm in C. meiocarpa ‘LP’ to 89.51 μm in C. oleifera ‘ASX09’. The pollen grains of oil-tea are monads and medium grade in pollen size. There were two types of polar views, including triangular or subcircular, with a polar axis length (P) ranging from 27.5 μm in C. oleifera ‘CY67’ to 59.04 μm in C. mairei (H. Lév.) Melch. var. lapidea (Y.C. Wu) Sealy. The equatorial views exhibited oblate, spherical, or oblong shapes, with an equatorial axis length (E) of 21.32 to 41.62 μm. The pollen exine sculpture was perforate, verrucate, and reticulate. The perforation lumina diameter (D) ranged from 0.29 μm in C. magniflora Chang to 1.22 μm in C. yuhsienensis Hu, and the perforation width (W) varied from 0.77 μm in C. osmantha to 1.40 μm in C. gauchowensis ‘HM349’, respectively. Qualitative clustering analysis (Q-type cluster) and principal component analysis (PCA) were conducted using eleven indexes of flower and pollen morphology, and the 18 oil-tea genotypes were classified into three categories. In addition, the correlation analysis showed that there was a significant correlation between pollen size and flower morphology or pollen exine sculpture. These results offer valuable information on the classification and identification of the 18 oil-tea germplasm resources.

Exochaenium natalense (Gentianaceae), a reinstated taxon endemic to KwaZulu-Natal, South Africa

Based on morphological and ecological considerations, Belmontia natalensis (syn. Exochaenium grande var. homostylum) is reinstated as Exochaenium natalense (Gentianaceae). It only occurs in a section of the coastal region of the Eastern Cape (Pondoland) and southern KwaZulu-Natal provinces, South Africa. Exochaenium natalense differs from E. grande, the only other South African Exochaenium taxon, by having smaller flowers (corolla diameter < 2 cm vs > 3 cm) with a different colour (white vs cream-salmon or yellow). Because the type material of E. natalense consists of two sheets, a lectotype is designated.

Integrative taxonomy in a rapid speciation group associated with mating system transition: A case study in the Primula cicutariifolia complex

Accurate species delimitation is the key to biodiversity conservation and is fundamental to most branches of biology. However, species delimitation remains challenging in those evolutionary radiations associated with mating system transition from outcrossing to self-fertilization, which have frequently occurred in angiosperms and are usually accompanied by rapid speciation. Here, using the Primula cicutariifolia complex as a case, we integrated molecular, morphological and reproductive isolation evidence to test and verify whether its outcrossing (distylous) and selfing (homostylous) populations have developed into independent evolutionary lineages. Phylogenetic trees based on whole plastomes and SNPs of the nuclear genome both indicated that the distylous and homostylous populations grouped into two different clades. Multispecies coalescent, gene flow and genetic structure analyses all supported such two clades as two different genetic entities. In morphology, as expected changes in selfing syndrome, homostylous populations have significantly fewer umbel layers and smaller flower and leaf sizes compared to distylous populations, and the variation range of some floral traits, such as corolla diameter and umbel layers, show obvious discontinuity. Furthermore, hand-pollinated hybridization between the two clades produced almost no seeds, indicating that well post-pollination reproductive isolation has been established between them. Therefore, the distylous and homostylous populations in this studied complex are two independent evolutionary lineages, and thus these distylous populations should be treated as a distinct species, here named Primula qiandaoensis W. Zhang & J.W. Shao sp. nov.. Our empirical study of the P. cicutariifolia complex highlights the importance of applying multiple lines of evidence, in particular genomic data, to delimit species in pervasive evolutionary plant radiations associated with mating system transition.

Relative importance of two bat species as pollinators of Neobuxbaumia tetetzo (Cactaceae): Evidences from morphometric and pollen load analyses

AbstractNeobuxbaumia tetetzo is a columnar cactus whose flowers are visited by the bat species Choeronycteris mexicana and Leptonycteris yerbabuenae. Although both bat species are considered the pollinators of N. tetetzo, the probability of pollination of each bat species has not been estimated. In this study, we determine the relative importance of C. mexicana and L. yerbabuenae as pollinators of N. tetetzo. The probability of pollination was estimated using two different approaches: (i) morphological correspondence between head (linear traits [total head length, snout length, and face height and width]) and cranial traits (shape traits) of bats and flower traits (linear [internal floral tube length including and excluding the nectary, corolla diameter, stamen length, style length, and corolla tube diameter] and shape traits), and (ii) pollen load analyses to estimate the percentage of occurrence (PO) and the pollination probability index (PPI). Our results showed a lack of a significant correspondence between both head and cranial traits of C. mexicana and the flowers of N. tetetzo, and linear morphological correspondence between total head length of L. yerbabuenae and flower length. Pollen loads of C. mexicana were composed by seven different pollen types, its PO and PPI were 41.87 ± 9.53% and 0.29, respectively. Leptonycteris yerbabuenae pollen loads were composed by three pollen types, with a PO of 78.29 ± 13.67% and a PPI of 0.67. Our results suggest that whereas C. mexicana has a low constancy to the flowers of N. tetetzo, L. yerbabuenae has a higher probability of pollination.

Morphological characterization of different genotypes of adenium

Adenium is recently gaining popularity as high value pot plant in the ornamental plant industry. Research on Adenium obesum with the basic objective for genetic improvement is being conducted at advance technology centre of soilless system, NAU, Navsari. As a component of breeding work, a study was conducted for morphological characterization of thirty three different genotypes of adenium that comprised of ten selected from local collection and the remaining twenty three from their crosses. Significant variation with regard to plant height, number of leaves, number of flowers, leaf and petal thickness, flower diameter, number of branches, corolla diameter and length, flower longevity, flower weight, flowers per cluster and number of flower flushes in a year were observed. Among all 33 genotypes, considering vegetative traits, Taiwan Dwarf showed significant dwarfness with more number of branches and smaller leaves while plant spread was observed maximum in Cross 14 and number of leaves in Cross 15. Further, fourteen genotypes were found suitable for flowering traits out of which two genotypes (Cross 2 and Cross 23) had flowers with 15 petals and eight genotypes (Cross 5,8,11,14,16,20,21 and dSh) had 10 petals while all others had five petals. Further, Cross 20 for large flower size, Cross 15 for number of flowers per cluster, flower longevity as well as for bearing maximum flowers in a year and Cross 18 and Cross 22 for more number of flower flushes in a year have been identified. These genotypes, can be further exploited for commercial application as well as for breeding work in floriculture industry.

Андромоноэция и протандрия у Oenanthe aquatica (Apiaceae)

The paper studies the synflorescence structure and flowering biology of the biennial monocarpic wetland plant Oenanthe aquatica. This species has a set of adaptations to prevent self-pollination, including generation of a pseudanthium, andromonoecy, intra- and interfloral protandry, and a specific sequence of flowering within its umbels. The synflorescence of O. aquatica is a panicle of umbels. The size of perfect and male flowers consistently decreases as the order of synflorescence axes grows. The size-related differences between perfect and staminate flowers on axes of the same branching order consist only in the length of their calyx abaxial teeth, corolla diameter, width of abaxial petals, length and width of anthers, and length and height of stylopodium. We have identified two arrangements of staminate flowers in O. aquatica: male flowers are located at the periphery or in the center of the umbellets. The share of staminate flowers in umbels increases as an axis order grows. The female phase of flowers on axes of one order occurs simultaneously within entire synflorescences with the male phase of flowers on axes of the next order, which might mean geitonogamy. Perfect flowers live for five to seven days, while staminate flowers function for no more than one day. The article contains 4 Figures, 2 Tables, 32 References. The Authors declare no conflict of interest.

Evolution of Autonomous Selfing in Marginal Habitats: Spatiotemporal Variation in the Floral Traits of the Distylous Primula wannanensis.

Outcrossing plant species are more likely to exhibit autonomous selfing in marginal habitats to ensure reproduction under conditions of limited pollinator and/or mate availability. Distyly is a classical paradigm that promotes outcrossing; however, little is known about the variation in floral traits associated with distylous syndrome in marginal populations. In this study, we compared the variation in floral traits including stigma and anther height, corolla tube length, herkogamy, and corolla diameter between the central and peripheral populations of the distylous Primula wannanensis, and assessed the variation of floral traits at early and late florescence stages for each population. To evaluate the potential consequences of the variation in floral traits on the mating system, we investigated seed set in each population under both open-pollinated and pollinator-excluded conditions. The flower size of both short- and long-styled morphs was significantly reduced in late-opening flowers compared with early opening flowers in both central and peripheral populations. Sex-organ reciprocity was perfect in early opening flowers; however, it was largely weakened in the late-opening flowers of peripheral populations compared with central populations. Of these flowers, disproportionate change in stigma height (elongated in S-morph and shortened in L-morph) was the main cause of reduced herkogamy, and seed set was fairly high under pollinator-excluded condition. Our results provide empirical support for the hypothesis on the evolution of delayed autonomous selfing in marginal populations of distylous species. Unsatisfactory pollinator service is likely to have promoted reproductive assurance of distylous plants with largely reduced herkogamy mimicking “homostyles.”

P.002 Effects of long-term ethanol consumption: study the possible interaction between brain-derived neurotrophic factor and serotonin brain systems

The results of a long-term study of the Campanula altaica phenotypic variation in the Western Siberian forest steppe (Novosibirsk) are described. Two ecotypes (subalpine and meadow) and three populations (Altai, Mountain Altai, and Tomsk) were assessed for the variation in phenological and several structural traits. The PAleontological STatistics (PAST) tool was used for statistical data processing. The adaptive changes in plant seasonal rhythms during their cultivation mainly appeared as a high lability of the flowering phase, whereas most phenological traits did not significantly differ at an intrapopulation level, reflecting an endogenous character of seasonal development. The intraspecific variation of structural traits is more pronounced: significant differences in the flowering shoot height, seed productivity per capsule, and several other characteristics are observed. The same traits of the accessions with different origins display different degrees and directions of changes. The least variable among the examined traits are the duration of vegetation, corolla diameter, and mass of 1000 seeds. High individual variation is a factor determining C. altaica as culturally sustainable species.

P.121 Effect of 5-HT1A receptor gene overexpression in hippocampus on behavior and neuroplasticity in BTBR mice – animal model of autism

The results of a long-term study of the Campanula altaica phenotypic variation in the Western Siberian forest steppe (Novosibirsk) are described. Two ecotypes (subalpine and meadow) and three populations (Altai, Mountain Altai, and Tomsk) were assessed for the variation in phenological and several structural traits. The PAleontological STatistics (PAST) tool was used for statistical data processing. The adaptive changes in plant seasonal rhythms during their cultivation mainly appeared as a high lability of the flowering phase, whereas most phenological traits did not significantly differ at an intrapopulation level, reflecting an endogenous character of seasonal development. The intraspecific variation of structural traits is more pronounced: significant differences in the flowering shoot height, seed productivity per capsule, and several other characteristics are observed. The same traits of the accessions with different origins display different degrees and directions of changes. The least variable among the examined traits are the duration of vegetation, corolla diameter, and mass of 1000 seeds. High individual variation is a factor determining C. altaica as culturally sustainable species.

Morphological variability of Veronica arguteserrata Regel & Schmalh. – new adventive species in Dnipro area

In the Dnipro area, Veronica arguteserrata is a new adventitious species of Asian origin from the family Plantaginaceae Juss., growing in the same ecological conditions – in shaded areas with moderate anthropogenic impact due to trampling, on loose soils and on parchment plots. The species is ephemeral: begins to grow in the second half of April, blooms in mid-May, bears fruit at the end of the same month, turns yellow in June and dies. We used 160 plants to study the morphological and ecological variability of Veronica arguteserrata. For analysis, we measured plant height, root length, length of the first and second internodes, length and width of leaf blade, number of peduncles, number of flowers, width and length of bract, corolla diameter, length and width of the fruits, number of seeds in the nest and number of fruits on the plant. The average values of all components were determined, the errors and population density, the number of individuals per 0.01 m2 were determined. Using a grid of 20 × 10 cm, divided into eight squares 5 × 5 cm, calculated the density of plants in tenfold repetition. The accuracy of density estimation, calculated as the ratio of error of the arithmetic mean to the arithmetic mean and expressed as a percentage, was 3.8–6.3%. The accuracy of assessment of other traits ranged from 2.2 to 7.5%, which is quite acceptable for field research. Analysis of the data showed that Veronica arguteserrata in the study area forms a fairly dense density of grasses, in which almost no other species are immersed. With increasing density, there is a tendency to increase the length of the first internode and reduce the area of the leaf blade, the number of peduncles, flowers and fruits on individuals. Within the parks, the plants were mowed at the end of the growing season. Probably due to mowing, as well as a slightly greater impact of trampling, the density of park populations is lower than on the highway near buildings. Synecological analysis showed that in the conditions of Dnipro area Veronica arguteserrata is a xeromesophyte, mesotroph, sciogeliophyte and ruderant. In the studied phytocenoses with increasing population of Veronica arguteserrata there is a tendency to decrease plant height, length of the second internode, length and width of the leaf blade, number of peduncles and flowers, length and width of bracts, peduncle length, corolla diameter and corolla diameter increase and box length. The highest variability was observed in the following signs from the vegetative sphere of Veronica arguteserrata plants: root length, leaf blade length, in the generative sphere: the number of flowers and of fruit on the plant. It is these features that make the largest share in the morphological variability of the studied species and determine its overall ecological and morphological plasticity. As a result of analysis of variance, the influence of population density on morphometric characteristics of plants was statistically proved. The population density has the greatest influence on the following features of the vegetative sphere: the length of the first internode and the length of the leaf blade; in the generative sphere: the diameter of the corolla and the length of the bract. Thus, the variability of these traits can be considered as a mechanism of intra-population morphological adaptations of the new adventitious species Veronica arguteserrata in the Dnipro area. The new adventitious species needs further monitoring studies to assess the level of impact on the ecosystems of Dnipro area.

New multipetalous variety G. Ad.2 in Adenium obesum

Research was conducted on Adenium obesum, a popular flowering pot plant with the basic objective for genetic improvement at Advance Technology Centre of soilless system, Department of Floriculture and Landscape Architecture, NAU, Navsari. Initially, hybridization was done involving ten parents (seven females and three males) in 2014 and their crosses were studied during 2015 to 2016. Among the crosses studied, a germplasm viz., MSDSH1 (Mung Siam x Double Sweet Heart) showed novel morphological character for colour and flower form having attractive purplish coloured ten petals. Further evaluation was carried out for stability and other flowering characters along with its parents viz., Mung Siam and Double Sweet Heart (DSH) and the local germplasm, Local Pink for two years 2016-17 and 2017-18. The MSDSH1 was significantly superior in terms of the number of flowers per cluster (10.23) and flower longevity on plant (11.91 days) as compared to parent and Local Pink as inferred from the pooled data of two years. Flower diameter was significantly superior in DSH at par with MSDSH1 (7.06 cm) while that of Mung Siam was minimum (5.89 cm), although the diameter of corolla was maximum (1.62 cm) in Local Pink while the length of corolla tube (4.01 cm) was maximum in Double Sweet Heart. Further, the maximum flower weight was observed in Double Sweet Heart (1.72 g) which was at par with MSDSH1 (1.61 g). Number of petals was ten in MSDSH1 and Double Sweet Heart as compared to Mung Siam and Local Pink with five petals. Since the genotype MSDSH1 was novel in flower colour with reddish purple shade and morphology with ten multipetalous flower form, besides being superior for the other flowering parameters, especially the number of flowers per cluster and flower longevity on plant, it was renamed as G. Ad.2 and released in SVRC, Gujarat.

Phenotypic intraspecific variability of Campanula altaica Ledeb. (Campanulaceae) in the Western Siberian forest steppe

The results of a long-term study of the Campanula altaica phenotypic variation in the Western Siberian forest steppe (Novosibirsk) are described. Two ecotypes (subalpine and meadow) and three populations (Altai, Mountain Altai, and Tomsk) were assessed for the variation in phenological and several structural traits. The PAleontological STatistics (PAST) tool was used for statistical data processing. The adaptive changes in plant seasonal rhythms during their cultivation mainly appeared as a high lability of the flowering phase, whereas most phenological traits did not significantly differ at an intrapopulation level, reflecting an endogenous character of seasonal development. The intraspecific variation of structural traits is more pronounced: significant differences in the flowering shoot height, seed productivity per capsule, and several other characteristics are observed. The same traits of the accessions with different origins display different degrees and directions of changes. The least variable among the examined traits are the duration of vegetation, corolla diameter, and mass of 1000 seeds. High individual variation is a factor determining C. altaica as culturally sustainable species.

Наследование длины и диаметра венчика у трубчатых цветков подсолнечника

Наследование длины и диаметра венчика у трубчатых цветков подсолнечника

CRITERIA OF THE CULTIVAR MODEL AND INTERRELATIONS AMONG ECONOMICALLY USEFUL CHARACTERISTICS OF CHAENOMELES IN CONNECTION WITH BREEDING

Background. Chaenomeles Lindl. is a popular ornamental and relatively young fruit crop. Genetic diversity of the genus favors breeding not only in these two areas, but also aiming at the development of cultivars of a universal type. To improve the efficiency of the breeding process, a cultivar model with the maximum combination of useful qualities in one genotype is vitally needed. The goal of this work was to identify the criteria for the model of a universal Chaenomeles cultivar, select cultivars that come closest to the model in their main economic traits, and find relationships among such characteristics. Materials and methods. The study engaged 21 Chaenomeles cultivars and forms selected for their valuable qualities from the Nikita Botanical Gardens collection. They were compared with the cultivar model using cluster analysis, while correlation analysis was employed to assess interrelations between traits. Results and conclusion. Criteria were identified for the universal cultivar model of Chaenomeles (ornamental and fruit purposes) according to 27 characteristics. Seven genotypes turned out to be closest to the universal model in a set of traits (4.44 units of the Euclidean distance): PХ4/9 (4.25 units), ‘Samurai’ (4.15 units), ‘Araks’ (4.01 units), ‘Afrikanych’, ‘Shatenka’ (3.9 units), ‘Krasavitsa Madlen’ and ‘Rosemary’ (3.7 units). Different degrees of correlation between the main 17 characteristics were observed. The strongest relationships was found between the beginning of flowering and its duration (r = –0.9), between the beginning of flowering and the duration of the dormancy period (r = 0.91), between the durations of flowering and dormancy periods (r = –0.82), between the corolla diameter, the flower’s originality (r = 0.83) and the overall ornamentality of the bush (r = 0.86). A tendency to dependence was observed in 12 pairs of traits (r = 0.46 to 0.61).

A comparison of coffee floral traits under two different agricultural practices

Floral traits and rewards are important in mediating interactions between plants and pollinators. Agricultural management practices can affect abiotic factors known to influence floral traits; however, our understanding of the links between agricultural practices and floral trait expression is still poorly understood. Variation in floral morphological, nectar, and pollen traits of two important agricultural species, Coffea arabica and C. canephora, was assessed under different agricultural practices (sun and shade). Corolla diameter and corolla tube length were larger and pollen total nitrogen content greater in shade plantations of C. canephora than sun plantations. Corolla tube length and anther filament length were larger in shade plantations of C. arabica. No effect of agricultural practice was found on nectar volume, sugar or caffeine concentrations, or pollen production. Pollen total nitrogen content was lower in sun than shade plantations of C. canephora, but no difference was found between sun and shade for C. arabica. This study provides baseline data on the influence of agronomic practices on C. arabica and C. canephora floral traits and also helps fill a gap in knowledge about the effects of shade trees on floral traits, which can be pertinent to other agroforestry systems.

Manipulating the frequency of intra-plant parts influences the foraging behaviour of a facultatively florivorous grasshopper

Studying density- (total available resources) and frequency-dependent (relative abundance of resources) foraging by herbivores can shed light on our understanding of insect–plant interaction. However, these concepts are rarely investigated on different resources within an individual plant, such as flowers and leaves, even though this can be informative on how each plant individual allocates different resources and defends against florivory and folivory. We performed manipulative experiments in an insectary on the facultatively florivorous grasshoppers (Xenocatantops humilis) and flowering twigs of the tropical dogwood (Mussaenda erythrophylla). The tropical dogwood was used because each plant has both typical leaves and modified calyx lobes of the flowers which function as attractive flags. By manipulating the densities and frequencies, in terms of biomass, of leaves and flag calyx lobes, we aimed to investigate the following questions: (1) Do the grasshoppers exhibit density- and/or frequency-dependent foraging of the intra-plant structures? (2) Do the grasshoppers show a dietary preference for the intra-plant structures? (3) Do relative and/or total biomasses of the intra-plant structures affect the intensity of corolla feeding? Our results provide support for frequency-, but not density-dependent foraging. We found that relative consumption and total herbivory increase with the relative biomass of the preferred flag calyx lobes, whereas a larger corolla diameter increases the intensity of corolla feeding. Our findings suggest that the colourful flag calyx lobes attract unwanted herbivores but could potentially be a decoy against folivory.