Number Of Stamens Research Articles

Physiological and biochemical assessment of a new three-breed carp cross

The article presents data about the physiological and biochemical assessment of a new three-breed carp cross. The basis for the creation of the cross was the theory of heterosis and the high combinational ability of both parent forms. The effect of heterosis was noted for a number of zootechnical indicators: body weight, head index, number of stamens on the anterior gill arch. The results of a comparative analysis of biochemical parameters such as alanine aminotransferase activity, glucose and total protein content are presented, which allowed us to conclude about the physiological state of the new three-breed cross, about the balance of its carbohydrate metabolism and high rates of protein metabolism, low level of hepatocyte destruction, high immune status and cellular immunity. The new cross is characterized by intensive metabolism of a greater proportion of mature neutrophils and a high level of cellular immunity according to the cytochemical coefficient of lysosomal cationic protein. When obtaining a new three-breed cross, the method of reciprocal hybridization of different carp breeds was used and the choice of an acceptable option with a pronounced effect of heterosis in terms of productivity and vitality was used. The article presents the results of immunological, hematological and biochemical blood tests of the new cross. Also, the article demonstrates the results of studies of the phagocytic activity of neutrophils and determines the content of non-enzymatic cationic protein in them. According to the results of the biochemical assessment, the new three-breed cross showed a high combination of its parent forms with the expected level of the heterosis effect.

Alternative splicing variants of IiSEP3 in Isatis indigotica are involved in floral transition and flower development

The SEPALLATA3 genes regulate several aspects of plant development. This study identified four distinct splicing isoforms of the SEPALLATA3 gene in Isatis indigotica (I. indigotica). IiSEP3-1 and IiSEP3-2 have eight exons and were named as IiSEP3-2/1. However, IiSEP3-3 and IiSEP3-4 with the missing sixth exon were labeled IiSEP3ΔK3. Furthermore, the IiSEP3-1 and IiSEP3-4 amino acids sequences lack the V90. IiSEP3 splicing variants were primarily expressed in floral organs, with petals showing the highest expression. Ectopic expression of IiSEP3-2 or IiSEP3-3 may cause early flowering and reduce the number of sepals, petals, and stamens. The ectopic expression of IiSEP3-2 resulted in cauline leaves and sepals converting to carpelloid structures. In contrast, the four floral whorls prematurely wilted, and the entire flower displayed an abortive state when IiSEP3-3 was expressed ectopically. Silencing the IiSEP3 gene of I. indigotica employing VIGS (tobacco rattle virus-mediated virus-induced gene silencing) technology using the TRV-IiSEP3-2/1 vector delayed flowering time and reduced the number of petals and stamens. Plants silenced with TRV-IiSEP3ΔK3 also exhibited similar phenotypes, including fewer sepals. The transcriptome analysis of silenced plants (TRV-IiSEP3-2/1 treatment group) indicated significant alterations in 1861 genes, with 1035 upregulated and 826 downregulated. TRV-IiSEP3ΔK3 treatment altered the expression of 2063 genes in plants, with 1289 genes upregulated and 774 genes transcription inhibited. Y2H and BIFC experiments revealed that IiSEP3-2 and IiSEP3-3 had distinct interacting proteins. Thus, we can conclude that IiSEP3-2 and IiSEP3-3 interact with different proteins, affecting floral transition and organ development in I. indigotica.

Floral morphology and development reveal extreme diversification in some species of Croton (Euphorbiaceae).

Floral diversity of Croton, the second largest genus in Euphorbiaceae, is currently under-explored. Several clades demonstrate an unusual floral morphology, e.g., lower or higher stamen number, bilateral symmetry and reduced ovary, but have never been investigated in a comparative study with typical Croton. This study examined morphology and ontogeny of flowers in nine Croton species from different clades within the genus with light and scanning microscopy, resin sectioning and micro-computed tomography. In staminate flowers, great variations of stamen number and arrangement are observed. The ancestral androecium likely consisted of two or more whorls with the outermost antepetalous stamen whorl developing centrifugally. Modification by reduction of the antepetalous whorl resulted in an outer alternipetalous stamen whorl in Croton section Moacroton, subgenus Quadrilobi. Several species in the subgenus Geiseleria show an independent reduction of stamen numbers by absence of a centrifugal development with the antepetalous whorl the first whorl to develop. Petal losses are observed in the distantly related C. setiger and C. dioicus. Chaotic stamen arrangement is found in C. celtidifolius (subgenus Adenophylli) as a result of a secondary stamen increase. In pistillate flowers, reduction of carpel numbers happened three times in the subgenus Geiseleria. C. monanthogynus has a bicarpellate ovary, while in C. setiger and C. michauxii the ovary is monocarpellate. Reduction of carpel number is linked with merism change and perianth reduction. The ovary in C. michauxii has basal placentation which is unique among all Croton. Moreover, strong bilateral sepals and nectaries are observed in species from section Julocroton. Therefore, the floral diversity of some species in the genus Croton could be explained by developmental modification of an ancestral form via reduction, rearrangement of stamen whorls, and symmetry shifts.

Jean-Baptiste Payer (1818–1860), prolific botanist and enlightened French citizen: his legacy in flower development and a need for a new, global compendium

ABSTRACT Jean-Baptiste Payer was among the pioneer botanists who promoted ontogeny as a clue to understanding the morphological nature and affinities of floral parts. He can be rightly seen as the father of floral developmental studies. In his magnus opus, Traité d’organogénie comparée de la fleur, he compared developmental stages across 333 species from 130 families sensu APGIV to explain phenomena such as the integration of the receptacle in the flower, the nature of the perianth, congenital fusion, shifts in stamen number, and the homology of carpels. His work is breathtaking not only in its scale and beauty, but also in providing a solid scientific basis for understanding the processes involved in the differentiation of flowers. Despite being pre-Darwinian, his research demonstrates the potential for evolutionary changes in flowers, in the context of the understanding of angiosperm classification at that time. Many of Payer’s ideas are still up-to-date and his observations are of great value in contemporary studies. In addition to botany, Payer had a lightning career in politics starting from the 1848 revolution. First a rioter, he then served two terms in the Constituent Assembly, before going back to science in 1852. In poor health, he died at the age of 42. This article aims at celebrating Payer as a scientist and a politician. We highlight a need for a new, global (encompassing at least all angiosperm orders) compendium on flower development that will facilitate analyses of evolutionary transitions of ontogenetic pathways. An outline of this research program is provided.

Ignoring within‐flower self‐fertilization and inbreeding depression biases estimates of selection on floral traits in a perennial alpine herb

Abstract Within‐flower self‐pollination should be the major source of self‐fertilization in mixed‐mating species that present single or few flowers simultaneously. It is also an often unmeasured source of selfing in species with many flowers open simultaneously. In self‐compatible species in which pistil and stamen numbers vary, the rate of within‐flower selfing should depend on the number of pistils and stamens, the timing of flowering and the morphology of subsidiary floral traits. The intensity and direction of selection on these traits should thus also depend on the level of inbreeding depression. Here, we measured the dependence of the within‐flower selfing rate on floral sex allocation, phenology, petal length and floral stalk height in a population of the perennial herb Pulsatilla alpina (Ranunculaceae) in which most individuals had single flowers. We estimated inbreeding depression in the population by comparing inbreeding coefficients between parents and seed progeny using microsatellite markers. We then estimated selection on the measured traits via female reproductive success at the flower level and compared our estimates with a hypothetical scenario in which inbreeding depression was assumed to be absent. Inbreeding depression was estimated to be severe (0.95). The within‐flower selfing rate varied widely among flowers and depended positively on stamen number and negatively on pistil number and flowering date, supporting the predictions of a mass‐action model. The dependence of the selfing rate on the measured floral traits consistently predicted (non‐linear) patterns of selection under high inbreeding depression that were distinct from those under a hypothetical scenario of no inbreeding depression. Synthesis. While previous research has emphasized the importance of mass‐action mating on selfing among flowers of plants with large floral displays, our results demonstrate its importance for selfing within individual flowers. They also demonstrate the importance of accounting for both the selfing rate and inbreeding depression when inferring selection on floral and other traits via female fitness.

Over-expression of a plant-type phosphoenolpyruvate carboxylase derails Arabidopsis stamen formation

We examined whether plant-type phosphoenolpyruvate carboxylase (PEPC) is involved in flower organ formation or not by over-expression in Arabidopsis. A wheat PEPC isogene Tappc3A, belonging to the ppc3 group, was targeted due to its preferential expression pattern in pistils and stamens. Transgenic Arabidopsis over-expressing Tappc3A exhibited irregular stamen formation, i.e., a lesser number of stamens per flower and shorter filaments in T2 and T3 generations. Irregular stamens were frequently observed in homozygous T4 lines, but no morphological change was observed in other floral organs. High-degree gene co-expression of Tappc3 isogenes with wheat SEEDSTICKs but not with other homeotic transcription factor genes for flower formation implicates that Tappc3 is under control by the class D genes of the ABCDE model to flower development. In addition, the conservation of CArG box sequences on the Tappc3 promoters supported the developmentally programmed gene expression of ppc3 in wheat flowering organs. Thus, this study provides the first experimental evidence for the critical regulation of plant-type PEPC for flower formation.

Morphological and phenological variation of flower colour morphs in a wild population of Opuntia streptacantha (Cactaceae)

Background and aims – Opuntia s.s. (Cactaceae) is one of the most diverse genera in the subfamily Opuntioideae, with approximately 220 species. The considerable morphological and anatomical diversity among these species has resulted in a remarkable adaptative plasticity, evident in both intra- and interspecific variability. Our study system is Opuntia streptacantha, which has two flower colour morphs: yellow and orange. The objective is to determine if there are morphological differences in the reproductive and vegetative structures between floral morphs. Material and methods – We measured 8 cladode traits (n = 20 cladodes for each floral morph) and 17 flower traits (n = 30 flowers per morph), and reproductive phenology was recorded for both morphs to describe their phenophases (n = 10 individuals per morph). Key results and conclusion – We found that floral colour morphs of O. streptacantha showed significant differences mostly associated with flower traits. Principal component analysis revealed seven components that explained 80% of the total variation, namely total flower length, number of stamens, distance between anther and stigma, number of pollen grains, style length, equatorial diameter of the ovarian chamber, pericarp width, and number of areole lines. Some individuals of O. tomentosa were classified as floral morphs of O. streptacantha, not having a clear separation between the species. The phenology of the floral colour morphs showed a slight lag in their peak flowering and fruiting. Very high flowering synchrony was found for each floral morph and between them. The modifications found in the flowers of O. streptacantha may be associated with a possible hybridization with O. tomentosa favouring the appearance of the two floral morphs.

Varietal diversity and selection of potential varieties of Petunia hybrida L. for commercial cultivation in Bangladesh

A study was conducted to compare the morpho-reproductive traits of twenty two genotype of Petunia in order to select superior and sustainable genotypes for commercial cultivation in Bangladesh during winter 2021-22. Thirteen qualitative and quantitative characters viz. stigma type, leaf shape, plant height (cm), number of branches, number of effective branches, days to flower initiation, number of flowers, duration of flowers, flowering duration, plant longevity, number of stamens, stamen length (cm) and petiole length (cm) were observed during the study period. The findings found that all morpho-reproductive traits differed significantly amongst the genotypes investigated, with the exception of the stamens, which were five in number. Highest quantitative variation was observed in days to flower initiation and longevity of the plants. Glow picotee blue showed the superior plant height (29.33 cm). Deep salmon had the shortest time to bloom initiation (52 days). Maximum number of flowers was recorded from ultra purple star (50) followed by ultra crimson star (49.67) while the duration of the flowers was maximum (6.67 days) in opera supreme white, prism pink, ultra burgundy star and ultra purple star. Opera supreme white had the longest flowering time (69.67 days). Whereas ultra purple star, ultra crimson star and ultra rose star had the longest lifespan (111 days). The genotypes deep salmon, ultra purple star, ultra red star, ultra rose star, opera supreme white, dreams midnight, and prism pink are recommended for commercial cultivation based on their overall morpho-reproductive performance. Jahangirnagar University J. Biol. Sci. 12(1 & 2): 23-33, 2023 (June & December)

Aerobiology of the Family Lamiaceae: Novel Perspectives with Special Reference to Volatiles Emission.

Lamiaceae is a botanical family rich in aromatic species that are in high demand such as basil, lavender, mint, oregano, sage, and thyme. It has great economical, ecological, ethnobotanical, and floristic importance. The aim of this work is to provide an updated view on the aerobiology of species from the family Lamiaceae, with an emphasis on novelties and emerging applications. From the aerobiology point of view, the greatest interest in this botanical family is related to the volatile organic compounds emitted by the plants and, to a much lesser extent, their pollen. Research has shown that the major volatile organic compounds emitted by the plants from this botanical family are monoterpenes and sesquiterpenes. The most important monoterpenes reported across studies include α-pinene, β-pinene, 1,8-cineole, menthol, limonene, and γ-terpinene. Most reports tend to cover species from the subfamily Nepetoideae. Volatile oils are produced by glandular trichomes found on aerial organs. Based on general morphology, two main types are found in the family Lamiaceae, namely peltate and capitate trichomes. As a result of pollinator-mediated transfer of pollen, Lamiaceae species present a reduced number of stamens and quantity of pollen. This might explain the low probability of pollen presence in the air from these species. A preliminary synopsis of the experimental evidence presented in this work suggests that the interplay of the organic particles and molecules released by these plants and their environment could be leveraged for beneficial outcomes in agriculture and landscaping. Emerging reports propose their use for intercropping to ensure the success of fructification, increased yield of entomophilous crops, as well as in sensory gardens due to the therapeutic effect of volatiles.

A new species of Polylepis (Rosaceae) from Santuario Nacional Pampa Hermosa, Peru

A new species of Polylepis from central Peruvian province of Tarma and present in Santuario Nacional Pampa Hermosa, is described and illustrated. The new species is most similar to Polylepis canoi but differs by its 3-foliate leaves, smaller oblong-lanceolate auriculate and sessile leaflets, shorter petioles with glandular hairs of reddish yellow resin, shorter pendulous axillary inflorescences 8–14 cm long with 6–13 flowers, and higher number of stamens (17–24). On present knowledge, the species has a tiny distribution and is further threatened by land use practices, so that we classify it as critically endangered. This discovery reinforces our understanding of the central Peruvian Andes as a poorly known center of biodiversity and endemism.

The Roles of Drift and Selection on Short Stamen Loss in Arabidopsis thaliana along an Elevational Gradient in the Spanish Pyrenees.

Traits that have lost function sometimes persist through evolutionary time. These traits may be maintained by a lack of standing genetic variation for the trait, if selection against the trait is weak relative to drift, or if they have a residual function. To determine the evolutionary processes shaping whether nonfunctional traits are retained or lost, we investigated short stamens in 16 populations of Arabidopsis thaliana along an elevational cline in the Spanish Pyrenees. We found a cline in short stamen number from retention of short stamens in high elevation populations to incomplete loss in low elevation populations. We did not find evidence that limited genetic variation constrains the loss of short stamens at high elevations nor evidence for divergent selection on short stamens between high and low elevations. Finally, we identified loci associated with short stamens in the Spanish Pyrenees that are different from loci associated with variation in short stamen number across latitudes from a previous study. Overall, we did not identify the evolutionary mechanisms maintaining an elevational cline in short stamen number but did identify different genetic loci underlying the variation in short stamen along similar phenotypic clines.

Taxonomic Evaluation of Zingiberaceae

The order Scitaminales is generally accepted as a well-knit assemblage of closely related and highly advanced monocotyledons and forms a natural group. Among the families of the order, the Zingiberaceae are the largest and are best represented in India, there being 21 genera including more than 200 species.The family is of special interest from the taxonomic stand point. On the basis of morphological differences, Schumann (1904) divided the Zingiberaceae into two subfamilies : the Zingiberoideae with many genera and Gostoidae with four genera namely, Costus (tropics), Monocostus (Peru), Dimerocostus (tropical America) and Tapeinochilus (Tabutu). The Costoideae differs from the rest of the family in showing vegetative and floral organization that is unique among the flowering plants. Therefore, morphologically, they form a natural group that deserves the status of a subfamily.It is accepted that taxonomy should be based on evidences from as many disciplines as possible in the final evaluation of its units. But among the Costoideae, only Costus has been studied in detail. As the other genera of the Costoideae agree with Costus in anatomy, Tomlinson (1956) considers it reasonable to assume that the features that serve to distinguish Costus from the Zingiberaceae are equally diagnostic for the Costoidae as a whole. A list of diagnostic characters obtained from various disciplines are given in table I. These evidences also reveal that Costoideae is distinct and forms a natural group deserving the rank of a subfamily.Certain-outstanding feature of the Costoideae are unique not only to the family, but also to the order Scitaminales as a whole. Perhaps, because of these Tomlinson (1956) has suggested that the Costoideae may possibly be given a family rank. However, although Tomlinson’s view is really encouraging, it is necessary to study the features of other genera of the Costoideae, with respect to various disciplines, in order to decide such an issue, instead of depending on the results obtained only on Costus.The Zingiberaceae is further subdivided into three tribes Globbeae, Hedychieae and Zingibereae on the basis of the nature of lateral staminodes and the ovary. For the taxonomic consideration of tribes, there are no adequate data. However, it can be said that further research in the divergent fields on many more genera may only help in solving the taxonomic problems.To a systematist the four families of the Scitaminales show an interesting floral organization, although they form a natural group because of certain morphological features common to all the families. A line of reduction in the number of stamens and ovules can be recognised in this order. The data available from various disciplines are too inadequate to verify the prevailing systematic arrangement of the families of the order. Nevertheless, the available embryological data consolidated in the table II unmistakably speak of a common ancestry of the families and their grouping in the order Scitaminales. At the same time certain distinguishing features of each family are probably suggestive of a family rank for each of them.

Preliminary selection of wild male kiwifruit (Actinidia callosa var. strigillosa C. F. Liang) accessions in North Sikkim, India, for future breeding programmes

ABSTRACT The flower morphology and phenology of 10 healthy, profusely flowering wild male kiwifruit (Actinidia callosa var. strigillosa C. F. Liang) accessions growing in North Sikkim district in Sikkim state, Northeast India, were analysed in 2021–2022. There was distinct variation among the accessions in the number of flowers per inflorescence, number of sepals and petals, colour of the sepals, arrangement of the petals, and average number of stamens, as well as the timing and duration of flowering. Accessions SKNFF-04 and SKNLC-21 were superior in terms of pollinating traits, with the highest average numbers of flowers and stamens per vine and the longest duration of flowering. Principal component analysis (PCA) revealed that the first and second principal components (PC1 and PC2) had eigenvalues greater than 1 and together explained 95.13% of the variation. Hierarchical cluster analysis categorised the accessions into two major clusters: Cluster I with eight accessions and Cluster II with the two superior accessions. The presence of the pleiochasium inflorescence type among all the observed accessions is of particular significance, as it can increase the efficacy of male selection in kiwifruit breeding programmes. This research sets the stage for further investigations into the potential advantages and unique characteristics of wild kiwifruit germplasm.

An updated infrageneric classification based on phylogenomics and character evolution in Hydrangea (Hydrangeaceae)

AbstractThe genus Hydrangea s.l. (Hydrangeaceae), a favorite among gardeners, comprises more than 80 species that are important understory plants in natural temperate and subtropical forests of the Northern Hemisphere. These species are hypervariable in morphology, especially in indumentum and floral characters, warranting a thorough exploration of the complex evolutionary history of morphological characters of the genus. Ideally, this is done within a robust phylogenetic framework with extensive taxon sampling. In this study, we propose a comprehensive taxonomic reassessment of Hydrangea based on a reconstruction of its molecular phylogeny based mainly on the chloroplast genome (plastome) and the most representative taxon sampling reported to date. Phylogenomic reconstruction yielded five well‐resolved major clades and three newly recognized subclades. Inspection of the 28 characters employed in traditional taxonomic revisions revealed homoplasy in many of these traits. Our results show that characters such as growth habit, woody stem type, number of enlarged marginal sepals, style and stamen number, fruit shape, and ovary position are useful for circumscribing infrageneric divisions. Unique synapomorphies are limited. For example, herb and subshrub growth habits are associated with all the species in H. sect. Deinanthe and sect. Cardiandra, respectively. Character state combinations are proposed for distinguishing infrageneric taxa. Based on a robust phylogenetic framework, our findings suggest a complex evolutionary history of Hydrangea morphological characters. Following the criterion of monophyly and considering the morphological consistency and synapomorphy of single and combined characters to diagnose relevant lineages, we update the classification of Hydrangea into 5 subgenera and 19 sections. Our proposed taxonomic scheme, based on a robust phylogenetic framework and in‐depth character study, provides an updated perspective on the infrageneric subdivision of Hydrangea s.l.

The transcription factor RhMYB17 regulates the homeotic transformation of floral organs in rose (Rosa hybrida) under cold stress.

Low temperatures affect flower development in rose (Rosa hybrida), increasing petaloid stamen number and reducing normal stamen number. We identified the low-temperature-responsive R2R3-MYB transcription factor RhMYB17, which is homologous to Arabidopsis MYB17 by similarity of protein sequences. RhMYB17 was up-regulated at low temperatures, and RhMYB17 transcripts accumulated in floral buds. Transient silencing of RhMYB17 by virus-induced gene silencing decreased petaloid stamen number and increased normal stamen number. According to the ABCDE model of floral organ identity, class A genes APETALA 1 (AP1) and AP2 contribute to sepal and petal formation. Transcription factor binding analysis identified RhMYB17 binding sites in the promoters of rose APETALA 2 (RhAP2) and APETALA 2-LIKE (RhAP2L). Yeast one-hybrid assays, dual-luciferase reporter assays, and electrophoretic mobility shift assays confirmed that RhMYB17 directly binds to the promoters of RhAP2 and RhAP2L, thereby activating their expression. RNA sequencing further demonstrated that RhMYB17 plays a pivotal role in regulating the expression of class A genes, and indirectly influences the expression of the class C gene. This study reveals a novel mechanism for the homeotic transformation of floral organs in response to low temperatures.

IiAGL6 participates in the regulation of stamen development and pollen formation in Isatis indigotica

The AGL6 (AGMOUSE LIKE 6) gene is a member of the SEP subfamily and functions as an E-class floral homeotic gene in the development of floral organs. In this study, we cloned IiAGL6, the orthologous gene of AGL6 in Isatis indigotica. The constitutive expression of IiAGL6 in Arabidopsis thaliana resulted in a late-flowering phenotype and the development of curly leaves during the vegetative growth period. Abnormal changes in floral organ development were observed during the reproductive stage. In woad plants, suppression of IiAGL6 using TRV-VIGS (tobacco rattle virus-mediated virus-induced gene silencing) decreased the number of stamens and led to the formation of aberrant anthers. Similar changes in stamen development were also observed in miRNA-AGL6 transgenic Arabidopsis plants. Yeast two-hybrid and BiFC tests showed that IiAGL6 can interact with other MADS-box proteins in woad; thus, playing a key role in defining the identities of floral organs, particularly during stamen formation. These findings might provide novel insights and help investigate the biological roles of MADS transcription factors in I. indigotica.

Ochradenus lakhpatensis (Resedaceae), a new species from Gujarat, India

A new species of the genus Ochradenus (Resedaceae), O. lakhpatensis, is described and illustrated. It is known from just five populations endemic to a relatively restricted area in Western India (Gujarat state), constituting the easternmost known records of the genus. It is morphologically similar to O. harsusiticus but differs in having pedicellate flowers and fruits, a higher number of stamens, wider fruit, and open fruit apex. A detailed description of the new species including colour photographs and an identification key to distinguish currently accepted Ochradenus species are provided. A preliminary conservation assessment of the species is also conducted under IUCN categories and criteria at the global level, resulting in the proposal of the Endangered category. In addition, we propose the exclusion of O. baccatus from the Indian flora, as it seems to be erroneous record.

A 49-bp deletion of PmAP2L results in a double flower phenotype in Prunus mume.

The double flower is an important trait with substantial ornamental value. While mutations in PETALOSA TOE-type or AG (AGAMOUS) genes play a crucial role in enhancing petal number in ornamental plants, the complete mechanism underlying the formation of double flowers remains to be fully elucidated. Through the application of bulked segregant analysis (BSA), we identified a novel gene, APETALA2-like (PmAP2L), characterized by a 49-bp deletion in double-flowered Prunus mume. β-Glucuronidase (GUS) staining and luciferase reporter assays confirmed that the 49-bp deletion in PmAP2L reduced its binding with Pmu-miRNA172a. Phylogenetic analysis and microsynteny analysis suggested that PmAP2L was not a PETALOSA TOE-type gene, and it might be a new gene controlling the formation of double flower in P. mume. Subsequently, overexpression of PmAP2L-D in tobacco led to a significant rise in the number of stamens and the conversion of stamens to petals. Furthermore, silencing of the homologue of RC5G0530900 in rose significantly reduced the number of petals. Using transient gene expression in P. mume flower buds, we determined the functional differences between PmAP2L-D and PmAP2-S in controlling flower development. Meanwhile, DNA-affinity purification sequencing (DAP-seq), yeast hybrid assays and luciferase reporter assays indicated that PmAP2L negatively regulated the floral organ identity genes by forming a repressor complex with PmTPL and PmHDA6/19. Overall, these findings indicate that the variation in PmAP2L is associated with differences in the regulation of genes responsible for floral organ identity, providing new insights into the double-flower trait and double-flower breeding in plants.

Modifications in floral morphology of Coffea spp. genotypes at two distinct elevations

Floral traits are influenced by elevation in various species, but no information is available for the Coffea canephora and C. arabica. It was hypothesized that: 1) number of stamens and petals can vary depending on the species and genotype within the same species; 2) variations in the morphological traits occur in response to the difference in elevation, 3) greater variability in flower morphology among C. canephora genotypes is expressed at high- than at low-elevation, due to environmental pressure, and 4) the changes in floral morphology due to alterations in elevation are more pronounced in C. canephora than in C. arabica. This study aimed to investigate the G × E interaction for morphological traits of coffee flowers and, based in genetic parameters estimation, explore the potential use of these traits in breeding programs. Experiment comprised of coffee plantations under full sun of both species at two elevations. The number of petals and stamens varied between five and six in C. canephora. At two elevations, Beira Rio 8 (C. canephora) genotype stood out for presenting the highest averages for all size traits related to corolla, and stigmatic lobes. The variability in floral morphology among C. canephora genotypes was not greater at high- than at low- elevation. Overall, flower size of all studied C. canephora and C. arabica genotypes was larger at low- than at high-elevation, but the stigmatic lobes length, the ratio between stigmatic lobe length and style length, and partially the ratio between anther length and stamen length were greater at high-elevation. C. arabica flowers were smaller and mostly irresponsive to elevation, in contrast with C. canephora flowers. There was a significant genotype by environment interaction for seven out of the nine traits, with a predominance of complex-type interactions. Conducting studies on morphological traits of flowers at a greater number of environments with distinct elevations can provide better insights into the potential use of these traits in studies of adaptability and stability of Coffea spp. genotypes to different environmental conditions, contributing to genetic improvement efforts to achieve resilience of coffee cultivation in the scenarios of climate change.

Floral morphology of 'Anand' rapid cycling Brassica oleracea .

Abstract The 'Anand' type of cytoplasmic male sterility (CMS) was introduced to Brassica oleracea through protoplast fusion (Cardi and Earle, 1997), providing a source of male sterility that is of value in producing F1 hybrid varieties of this species without the cold sensitivity of 'Ogura' cytoplasm. In this species, as in others in which it has been introduced, 'Anand' mitochondria are associated with flower abnormalities. The best lines have been used by commercial breeders. This paper describes 'Anand' flower abnormalities in further detail. Rapid cycling brassica with 'Anand' cytoplasm may have promise as a model system for research on floral patterning. Materials and Methods. Three lines of rapid cycling B. oleracea carrying the 'Anand' cytoplasm and one wild type were grown. The flower morphology of 'Anand' lines was classified as good in F25-F-1A, fair in F25-F-6B, and poor in F23-F-1B (Cardi and Earle, 1997). Seedlings were started in an indoor growth room, but were maintained in a naturally lit greenhouse at 20° night, 25° day during flowering. Five flowers on 5 plants of each line were examined. Results. Morphological abnormalities affected all floral parts (Table 1). There was substantial variation among flowers on individual plants and among lines but little within lines. Conclusions. "Good" flowers have large petals that push open the sepals before the carpel elongates. Female fertility could be reduced due to occlusion of the stigma or physical damage caused by the stigma pressing against the end of a sepal and kinking the style. Female fertility in some flowers was unlikely because the carpel suture failed to fuse. In some cases the edge of the split carpel was sepal-like, consistent with the absence of SEPALLATA expression. The stigma on a sepal represents the converse. Stamens were most strongly affected, with outer stamens most reduced. This whorl is the one most frequently suppressed in flowering plants (Masters, 1869). The number of stamens was reduced to varying degrees. First to be lost was one or both of the pair outside the petals. Then the outer pair inside the petals was affected. One or both of these stamens could either be lost or doubled to give 3 to 5 stamens. Again a positional cue for stamens appears to be weakened. Anther development was often limited, the expected and desired consequence of the Anand genotype. Some undehisced " good " anthers contained pollen. There is variation even among the lines initially described as " good ". Further selection among these may help identify those that are most promising for further use in hybrid production.