Organogenesis of the male inflorescence and flowers of Myrica esculenta

1978 ◽  
Vol 56 (19) ◽  
pp. 2415-2423 ◽  
Author(s):  
Alastair D. Macdonald
Keyword(s):  
Flower Development ◽  
Male Flower ◽  
Distal Region ◽  
Male Inflorescence ◽  
Inflorescence Axis ◽  
Floral Apex ◽  
Reduction Series ◽  
Secondary Inflorescence ◽  
Myrica Esculenta ◽  
Floral Bracts

Organogenesis of the male inflorescence and flowers of Myrica esculenta is described. The inflorescence is a panicle of spikes. The myricaceous flower consists of up to five stamens and two transversal bracts. The organography and organogenesis of the flowers of the distal region of the inflorescence are similar to the organography and organogenesis of the flowers of the secondary inflorescence axes in the intermediate region of the inflorescence. The presence of a transversal pair of bracts on the floral axis is variable. Only in monostaminate flowers does a stamen terminate an axis. This is a function of the monostaminate flower being positioned at the extreme distal region of the primary inflorescence or secondary inflorescence axis. Five-, four-, three-, and two-stamened flowers occur as an acropetal reduction series along the primary inflorescence or secondary inflorescence axis. Whether or not floral bracts are present, the stamens arise simultaneously in a whorl on the flank of a flattened floral apex. The stamens do not form in the axils of the floral bracts. The pattern of male flower development is the same in all other species examined. It is concluded that this pattern of flower development illustrates a conservative sequence of ontogenetic events within the family. This is of taxonomic and phylogenetic significance.

scholarly journals Molecular Cloning and Expression Analysis of a MADS-Box Gene (GbMADS2) from Ginkgo biloba

2015 ◽  
Vol 43 (1) ◽  
pp. 19-24 ◽  
Author(s):  
Xiaohui WANG ◽  
Junhuan CHENG ◽  
Feng XU ◽  
Xingxiang LI ◽  
Weiwei ZHANG ◽  
...  
Keyword(s):  
Expression Analysis ◽  
Ginkgo Biloba ◽  
Flower Development ◽  
Time Course ◽  
Male Flower ◽  
Cloning And Expression ◽  
Pcr Analysis ◽  
Mads Box ◽  
Typical Structure ◽  
Mads Box Gene

As a kind of transcription factors gene family, MADS-box genes play an important role in plant development processes. To find genes involved in the floral transition of Ginkgo biloba, a MADS-box gene, designated as GbMADS2, was cloned from G. biloba based on EST sequences by RT-PCR. Sequence analysis results showed that the cDNA sequence of GbMADS2 contained a 663 bp length ORF encoding 221 amino acids protein, which displayed typical structure of plant MADS-box protein including MADS, I, and K domains and C terminus. The sequence of GbMADS2 protein was highly homologous to those of MADS-box proteins from other plant species with the highest homologous to AGAMOUS (CyAG) from Cycas revoluta. The phylogenetic tree analysis revealed that GbMADS2 belonged to AGAMOUS clade genes. Real-time PCR analysis indicated that expression levels of GbMADS2 gene in female and male flower were significantly higher than those in root, stem, and leaves, and that GbMADS2 expression level increased along with time of flower development. The spatial and time-course expression profile of GbMADS2 implied that GbMADS2 might be involved in development of reproductive organs. The isolation and expression analysis of GbMADS2 provided basis for further studying the molecular mechanism of flower development in G. biloba.

Ontogeny of floral organs and morphology of floral apex in Phellodendron amurense (Rutaceae)

2002 ◽  
Vol 50 (5) ◽  
pp. 633 ◽  
Author(s):  
Qingyuan Zhou ◽  
Yinzheng Wang ◽  
Xiaobai Jin
Keyword(s):  
Laser Scanning ◽  
Male Flower ◽  
Female Flower ◽  
Laser Scanning Confocal Microscopy ◽  
Morphological Evidence ◽  
Phellodendron Amurense ◽  
Flower Buds ◽  
Floral Organs ◽  
Floral Apex ◽  
Female Flowers

The ontogeny of floral organs and the morphology of floral apex in the dioecious Phellodendron amurense Rupr. were investigated by light microscopy (LM), scanning electron microscopy (SEM) and laser scanning confocal microscopy (LSCM). Investigations indicated that P. amurense is hermaphroditic in its organisation and a common set of floral organs (sepals, petals, stamens and carpels) arise in all flowers during the early stages of development. Later, selective abortion of gynoecium and androecium occurs resulting in dimorphic unisexual flowers. The carpels in male flower buds become different from those in female flower buds soon after their initiation. The stamens of female flowers are not differentiated into anthers and filaments before abortion. The poorly differentiated carpel of male flowers never develops normal structures. Floral morphological evidence supports that Zanthoxylum, Tetradium and Phellodendron are related to one another in a linear sequence. LSCM revealed some interesting features on the apical meristem surface such as zonal differentiation, a triangular or sectorial cell, radiating cell files and linear rows of anticlinal cell walls fluorescing relatively brightly. The concept of carpel-enhancing meristem in the floral apex is tentatively proposed to account for the different fates of carpel development in male and female flowers in P. amurense.

scholarly journals Differential gene expression among three sex types reveals a MALE STERILITY 1 (CpMS1) for sex differentiation in papaya

2019 ◽  
Vol 19 (1) ◽  
Author(s):  
Dessireé Zerpa-Catanho ◽  
Jennifer Wai ◽  
Ming Li Wang ◽  
Li’ang Yu ◽  
Julie Nguyen ◽  
...  
Keyword(s):  
Sex Determination ◽  
Male Sterility ◽  
Flower Development ◽  
Sex Differentiation ◽  
Male Flower ◽  
Organ Development ◽  
Flower Buds ◽  
Flower Organ ◽  
Expression Of Genes ◽  
Development Processes

Abstract Background Carica papaya is a trioecious plant species with a genetic sex-determination system defined by sex chromosomes. Under unfavorable environmental conditions male and hermaphrodite exhibit sex-reversal. Previous genomic research revealed few candidate genes for sex differentiation in this species. Nevertheless, more analysis is still needed to identify the mechanism responsible for sex flower organ development in papaya. Results The aim of this study was to identify differentially expressed genes among male, female and hermaphrodite flowers in papaya during early (pre-meiosis) and later (post-meiosis) stages of flower development. RNA-seq was used to evaluate the expression of differentially expressed genes and RT-qPCR was used to verify the results. Putative functions of these genes were analyzed based on their homology with orthologs in other plant species and their expression patterns. We identified a Male Sterility 1 gene (CpMS1) highly up-regulated in male and hermaphrodite flower buds compared to female flower buds, which expresses in small male flower buds (3–8 mm), and that might be playing an important role in male flower organ development due to its homology to MS1 genes previously identified in other plants. This is the first study in which the sex-biased expression of genes related to tapetum development in the anther developmental pathway is being reported in papaya. Besides important transcription factors related to flower organ development and flowering time regulation, we identified differential expression of genes that are known to participate in ABA, ROS and auxin signaling pathways (ABA-8-hydroxylases, AIL5, UPBEAT 1, VAN3-binding protein). Conclusions CpMS1 was expressed in papaya male and hermaphrodite flowers at early stages, suggesting that this gene might participate in male flower organ development processes, nevertheless, this gene cannot be considered a sex-determination gene. Due to its homology with other plant MS1 proteins and its expression pattern, we hypothesize that this gene participates in anther development processes, like tapetum and pollen development, downstream gender specification. Further gene functional characterization studies in papaya are required to confirm this hypothesis. The role of ABA and ROS signaling pathways in papaya flower development needs to be further explored as well.

Floral development of Maidenia rubra Rendle, (Hydrocharitaceae)

1983 ◽  
Vol 31 (6) ◽  
pp. 585 ◽  
Author(s):  
CA McConchie
Keyword(s):  
Floral Development ◽  
Floral Morphology ◽  
Male Flower ◽  
Pollen Grains ◽  
Anther Wall ◽  
Male And Female ◽  
The Third ◽  
Male Inflorescence ◽  
Single Flower

Floral development of Maidenia rubra was followed from initiation to maturity. Plants are dioecious. Both male and female inflorescences develop from complexes initiated subapically. Complexes have three meristematic components that include two inflorescence initials flanking a central primordium; these form sequentially in the axil of the preceding initial. The third component also produces an inflorescence and branches sympodially to form further floral initials that have a spiral arrangement. The female inflorescences produce a single flower only with an inferior, unilocular ovary and three sepals, staminodes and bifid stigma. In the locule, numerous bitegmic ovules, borne panetally, are produced. A male inflorescence produces hundreds of small flowers that are released and float to the surface individually. Each male flower has three sepals, a staminode and two stamens, each anther consisting of three locules with eight pollen grains. Prior to maturation, the anther wall breaks down leaving a membraneous layer that assists in binding the octad of pollen grains together. Both male and female inflorescences are enclosed in a pair of fused bracts. The floral morphology is compared with other closely related genera in the Hydrocharitaceae and the unique features are assessed.

Net alignment of cellulose in the periclinal walls of the shoot apex surface cells in Kalanchoe blossfeldiana. II. Flower development

1990 ◽  
Vol 68 (12) ◽  
pp. 2678-2684 ◽  
Author(s):  
Amy J. Nelson
Keyword(s):  
Key Words ◽  
Shoot Apex ◽  
Flower Development ◽  
Cell Layer ◽  
Floral Organogenesis ◽  
Floral Apex ◽  
Kalanchoe Blossfeldiana ◽  
Periclinal Walls ◽  
Circumferential Reinforcement ◽  
Kalanchoë Blossfeldiana

Dome geometry and the pattern of net cellulose alignment in the periclinal walls of the surface cells of Kalanchoe blossfeldiana were examined during sequential stages of flower development. Floral apices of photoperiodically induced plants were dissected, stained, and observed under a dissecting microscope. The outermost cell layer(s) of the surface was surgically removed from the floral apex and viewed under a polarizing microscope. Correlations were found between the geometry of the dome, the pattern of cellulose in the surface cells, and the pattern of initiation of floral organs at the apex. Tangentially aligned cellulose was always observed around the periphery of the floral dome, whereas no net alignment of cellulose typically occurred in the centermost region. Circumferential reinforcement of cellulose was consistently observed at sites of incipient organ initiation, and the pattern of cellulose alignment on emerging primordia correlated with the type of organ development. No strict dependence was evident between the number and positioning of one whorl of floral ogans and that of the previous whorl. Key words: shoot, cellulose, flower, floral, organogenesis.

Floral development of Ruppia maritima var. maritima

1974 ◽  
Vol 52 (7) ◽  
pp. 1607-1612 ◽  
Author(s):  
U. Posluszny ◽  
R. Sattler
Keyword(s):  
Floral Development ◽  
Early Ontogeny ◽  
Main Axis ◽  
Ruppia Maritima ◽  
Procambial Strand ◽  
Inflorescence Axis ◽  
Floral Apex ◽  
Median Position ◽  
Floral Bud

A hyaline, unvascularized sheath envelops a portion of the inflorescence near maturity. Though resembling an appendage of the main axis, in early ontogeny it develops as a prophyll of the renewal growth apex below the inflorescence. Two flowers develop on the inflorescence axis, subopposite each other. Fertile appendages are initiated in an acropetal sequence on each floral bud. The first to form, in the median position, are the two stamens, the lower preceding the upper. Each stamen develops two bisporangiate thecae separated by a broad connective. A dorsiventral outgrowth is initiated slightly abaxially near the tip of the connective at the stage of theca differentiation. This outgrowth appears to be homologous with a similar outgrowth in Potamogeton densus, but not with the sterile appendages of the Potamogeton flower which, by some authors, have incorrectly been interpreted as connective outgrowths. Each carpel arises as a radial primordium which becomes peltate after its inception. One ovule is initiated at the adaxial portion (Querzone). The stigma becomes broad and flat, lobing at its margins. A slight outgrowth develops at the abaxial wall of the carpel. The floral apex has a two-layered tunica. The primordia of the stamens, carpels, and ovules arise by periclinal divisions in the second layer. Procambial development is acropetal following closely primordial inception. Each appendage, including the ovule, receives one procambial strand. The outgrowths of the connective and the carpel lack procambium.

scholarly journals Forecast of Total Pollen Counts of Sugi (Cryptomeria japonica) from the Amount of Male Flower Development and the Revised Total Pollen Counts.

2000 ◽  
Vol 103 (6) ◽  
pp. 742-747
Author(s):  
Hiroshi Ogasawara ◽  
Osamu Adachi ◽  
Masafumi Sakagami ◽  
Shiro Yoshimura ◽  
Tetsuzo Fujitani
Keyword(s):  
Flower Development ◽  
Cryptomeria Japonica ◽  
Male Flower ◽  
Pollen Counts ◽  
Total Pollen

Floral development of Comptonia peregrina (Myricaceae)

1974 ◽  
Vol 52 (10) ◽  
pp. 2165-2169 ◽  
Author(s):  
Alastair D. Macdonald
Keyword(s):  
Floral Development ◽  
Early Stage ◽  
Male Flower ◽  
Female Flower ◽  
Median Plane ◽  
Distal Portion ◽  
Second Order ◽  
Third Order ◽  
Floral Apex ◽  
Growth Activity

Early stages of development of the male and female flower are similar; two second-order bracts arise in the transversal plane on either side of the floral apex before the apex flattens and becomes somewhat concave because of growth activity at the flank of the apex. In the female flower, the gynoecium develops as an extension of the girdling gynoecial primordium and the two primordial stigmas each result from more rapid growth in the median plane at the distal portion of the gynoecial wall. The floral apex resumes growth to form the unitegmic ovule. Third-order lanceolate-shaped bracts develop from a meristem situated in the axil of each second-order bract. In the male flower, staminate primordia arise at three or four loci on the ridge surrounding the apex. The apex briefly resumes growth. Growth of the second-order bracts terminates at an early stage. The floral construction is compared to other myricaceous species. It is concluded that the axillary scale-like bracts of the female flower are third-order bracts; the gynoecium does not overtop the second-order axis and the female flower is not a reduced cyme; the male flower is more floral- than inflorescence-like compared to some other myricaceous species.

Ontogeny of the vegetative and floral apex of Calycanthus occidentalis

1972 ◽  
Vol 50 (6) ◽  
pp. 1349-1356 ◽  
Author(s):  
N. G. Dengler
Keyword(s):  
Early Ontogeny ◽  
Apical Growth ◽  
Axillary Buds ◽  
The Third ◽  
Early Stages ◽  
Floral Apex ◽  
Intercalary Meristem ◽  
Floral Bracts ◽  
Parenchyma Tissue

The early ontogeny of the flower of Calycanthus occidentalis is described. The pattern of initiation, procambial development, apical growth, and marginal growth of floral bracts and tepals is similar to that of the leaf, while stamens, staminodia, and carpels are not leaf-like in some aspects of their development. The initiating periclinal divisions of staminodia and carpels occur in the third and fourth layers from the surface and procambium development in the carpel is discontinuous and bidirectional. These similarities in development to some axillary buds are probably due to the position of the young primordia which are isolated from developing procambial strands by parenchyma tissue. The concave floral cup is formed through the activity of an intercalary meristem concurrently with the early stages of appendage ontogeny.

Inflorescence and flower development in wild-type and sid mutant Melilotus alba, white sweetclover

2002 ◽  
Vol 80 (7) ◽  
pp. 732-740 ◽  
Author(s):  
Ann M Hirsch ◽  
Rebecca SN Krupp ◽  
Yimei Lin ◽  
Susan S Wang ◽  
Weigang Yang ◽  
...  
Keyword(s):  
Flower Development ◽  
Floral Development ◽  
Abc Model ◽  
Wild Type ◽  
Inflorescence Development ◽  
Melilotus Alba ◽  
Secondary Inflorescence

White sweetclover, Melilotus alba Desr. (Fabaceae), produces white, papilionoid flowers on a simple raceme. Individual floral apices originate in the axil of a bract. Each flower consists of five alternating whorls that, from outside to inside, consist of (i) five sepals, (ii) five petals, of which two fuse along their abaxial edges to form the keel, (iii) five antesepalous stamens, (iv) five antepetalous stamens with shorter filaments, and (v) a single carpel containing two to four ovules. The development of the wild-type sweetclover inflorescence and flowers is described in detail and compared with a mutant in which secondary inflorescences, instead of individual flowers, developed in axils of the bracts, especially at the base of the inflorescence. This white sweetclover mutant, designated sid for "secondary inflorescence development", might serve as a test of the ABC model of floral development, which was based on the model plants Antirrhinum and Arabidopsis.Key words: white sweetclover, inflorescence, flower, development, sid mutant.

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