Life Sciences Commons^™

Rugaspermum Minuta - A New Species Of The Seed Genus Rugaspermum From The Triassic Of Nidpur, India, Nupur Bhowmik, Shabnam Parveen

Turkish Journal of Botany

This paper provides a description of a new species of Rugaspermum D.D.Pant & Basu, R. minuta Bhowmik & Parveen, from the Nidpur Triassic beds. The dispersed seeds were recovered after macerating large chunks of shale in hydrofluoric acid. The structurally preserved compressed seed is platyspermic, orthotropus, and oval- to barrel-shaped with a short beak-like micropyle. The surfaces of the seeds are wrinkled and there is a wide lateral ridge running from the apex to the base on both the obverse and reverse sides. Upon maceration, the seed yielded 4 membranes: outer, inner, nucellar, and megaspore membranes. The outer cuticle of …

Verbascum Hasbenlii (Scrophulariaceae), A New Species From Turkey, Zeki̇ Aytaç, Hayri̇ Duman

Turkish Journal of Botany

Verbascum hasbenlii Aytaç & H.Duman sp. nov. (sect. Bothrosperma Murb.) is described and illustrated from Turkey. This new species was collected in B1 Çan (Çanakkale Province) area. V. hasbenlii appears to be closely allied to V. luciliae (Boiss.) O.Kuntze and V. haraldi-adnani Parolly & Eren. Its affinities with this and other related species are discussed. The characteristic features of pollen, seed, stomata structure, and hairs are studied using a scanning electron microscope and the distribution of the new species in Turkey is given.

Analysis Of Chenopodiaceae-Amaranthaceae Airborne Pollen In Salamanca, Spain, David Rodríguez De La Cruz, Estefania Sanchez-Reyes, José Sánchez-Sánchez

Turkish Journal of Botany

Chenopodiaceae-Amaranthaceae pollen represents an allergenic risk for pollen-sensitive people. The aim of this study was to describe the Chenopodiaceae-Amaranthaceae pollen dynamics in the atmosphere of Salamanca (mid-west Spain) during the years 2000-2007. Measurements were performed by the volumetric method using a Burkard spore trap located in the urban centre at the height of 20 m above ground level. This pollen type was mainly detected in the atmosphere between late spring and late summer, with an Atmospheric Pollen Season (APS) registered between late May and early October and maximum concentrations detected in August. The intradiurnal pattern, calculated by means of 3 …

Developing Biocontainment Strategies To Suppress Transgene Escape Via Pollen Dispersal From Transgenic Plants, Hong Seok Moon

Doctoral Dissertations

Genetic engineering is important to enhance crop characteristics and certain traits. Genetically engineered crop cultivation brings environmental and ecological concerns with the potential of unwanted transgene escape and introgression. Transgene escape has been considered as a major environmental and regulatory concern. This concern could be alleviated by appropriate biocontainment strategies. Therefore, it is important to develop efficient and reliable biocontainment strategies.

Removing transgenes from pollen has been known to be the most environmentally friendly biocontainment strategy. A transgene excision vector containing a codon optimized serine resolvase CinH recombinase (CinH) and its recognition sites RS2 were constructed and transformed into tobacco …

Developmental Evolution Of The Progamic Phase In Nymphaeales, Mackenzie Lorraine Taylor

Doctoral Dissertations

The period between pollination and fertilization, or the progamic phase, is a critical life history stage in seed plants and innovations in this life history stage are hypothesized to have played an important role in the diversification of flowering plants. Over the course of this dissertation research, I investigated programic phase development in Nymphaeales (water lilies), an ancient angiosperm lineage that diverged from the basalmost or next most basal node of the angiosperm phylogenetic tree and that is represented in the oldest angiosperm fossil record. I used field experiments and microscopy to document pollination biology, breeding system, and reproductive developmental …

Pollen Morphology Of The Genus Seseli L. (Umbelliferae) In Turkey, Ebru Doğan Güner, Hayri̇ Duman, Nur Münevver Pinar

Turkish Journal of Botany

Morphological features of pollen of 11 Turkish taxa belonging to the complex genus Seseli L. were examined using light and scanning electron microscopy. On the basis of exine sculpturing, 3 main types were recognised in Seseli: Type 1, rugulate at equator, psilate-perforate at pole; Type 2, striate-reticulate at equator, rugulate at pole; and Type 3, rugulate at equator, striate at pole. The study revealed that palynological characters display taxonomic significance in the genus.

Pollen Analysis Of Honeys From Varaždin County, Croatia, Mirjana Sabo, Mirjana Potocnjak, Ines Banjari, Danijela Petrovic

Turkish Journal of Botany

The palynological properties of 8 honey samples commercially produced in 1 region in Croatia (Varazdin County) were determined. Each sample was examined to determine the pollen percentage and pollen spectrum. On the basis of honey pollen analysis, in these 8 samples different botanical origin was determined. In total, 20 different types of pollen grains were identified. The dominant group of pollen grains consisted of Castanea sativa Mill. in samples 2 and 8, Brassica napus L. in samples 4 and 5, and Trifolium pratense L. in samples 6 and 7. The pollen analysis revealed 6 unifloral and 2 multifloral honeys. Analysis …

Pollen Interception By Linyphiid Spiders In A Corn Agroecosystem: Implications For Dietary Diversification And Risk-Assessment, Julie A. Peterson, Susan Romero, James D. Harwood

West Central Research and Extension Center, North Platte

Dietary diversification, including consumption of plant tissues such as pollen, can enhance the fecundity of generalist predators, resulting in improved control of pest prey. Supplemental pollen feeding has been observed in many natural enemies, including sheet-web spiders (Araneae: Linyphiidae), which represent a major component of food webs in agroecosystems. Their horizontal, ground-based webs have the potential to intercept pollen grains during anthesis of crop plants, providing the opportunity for consumption of pollen to occur. In laboratory feeding trials, Frontinella communis and Tennesseellum formicum (Araneae: Linyphiidae) readily fed on pollen grains dusted on their webs, with 82 and 92% of spiders …

Pollen And Seed Morphology Of Velezia L. (Caryophyllaceae) Genus In Turkey, İlham Eröz Poyraz, Ebru Ataşlar

Turkish Journal of Botany

In this study, pollen and seed morphology of Velezia L. (Caryophyllaceae) species in Turkey were investigated by light and scanning electron microscopy. The genus is represented by 5 species in Turkey: V. tunicoides P.H.Davis, V. hispida Boiss., V. quadridentata Sibth. & Sm., V. pseudorigida Hub.-Mor. and V. rigida L. Endemism ratio of the genus is 60%, which shows that Turkey is the gene center for this genus. The pollen grains of Velezia species are radially symmetrical and isopolar, oblate-spheroidal, operculate, and polypantoporate, pores with conical spinules on operculum. Pollen ornamentation, pore numbers, exine thickness, pore diameter, operculum ornamentation, and spinule …

Comparative Rapd Analysis And Pollen Structure Studies Of Bellis Perennis L., Nesli̇han Kavalcioğlu, Leyla Açik, Nur Münevver Pinar

Turkish Journal of Botany

Random amplified polymorphic DNA (RAPD) is one of the easiest and most commonly used molecular techniques for genetic variability analysis. In the present study, the genetic diversity of analysis of Bellis perennis L. collected in 4 Turkish geographical locations was investigated by RAPD-PCR analysis. In addition to RAPD, pollen analysis of the 4 plant populations was also conducted. Out of 40 RAPD primers tested, 12 exhibited distinct banding patterns showing 45% to 79% polymorphism. Plants from these 4 localities were almost the same morphologically. Considerable differences were observed in the RAPD profile and pollen shape of plants from the Rize/Dereköy …

A New Species Of Echinops (Asteraceae) From Turkey, Cem Vural, Mustafa Kemal Bi̇ter, Mehmet Yaşar Dadandi

Turkish Journal of Botany

Echinops dumanii C.Vural is described and illustrated from Adana province, South Anatolia, Turkey. It is considered to be endemic to Turkey. The morphological differences from the closely related species Echinops phaeocephalus Hand.-Mazz. are discussed. The International Union for Conservation of Nature (IUCN) threat category and observations on the ecology of the populations are noted. The geographical distribution of the new species is mapped.

Functional Analysis Of Receptor-Like Kinases In Pollen-Pistil Interactions In Arabidopsis Thaliana, Mini Aggarwal

Masters Theses 1911 - February 2014

Rac/Rop GTPases are molecular switches in plants that control the growth of polarized cells such as pollen tubes and root hairs, differentiation, development, actin dynamics, production of reactive oxygen species (ROS) and disease resistance. These small GTPases are activated by guanine nucleotide exchange factors (GEFs) that replace GDP for GTP and are referred to as RopGEFs in plants. To identify upstream components of the RopGEF regulated signaling pathways, GEF1 from Arabidopsis thaliana was used as a bait to screen a seedling cDNA library in a yeast two-hybrid system. This yielded members of a small family of the Catharanthus roseus Receptor-like …

Pollen And Seed Morphology Of The Genus Hesperis L. (Brassicaceae) In Turkey, Münevver Pinar, Ahmet Duran, Tali̇p Çeter, G. Ni̇lhan Tuğ

Turkish Journal of Botany

Pollen and seed morphology were examined in 35 specimens representing 25 Turkish species of the taxonomically complex genus Hesperis L. by light and scanning electron microscopes. Three main types and 2 subtypes were recognized based on the seed coat surface, pollen shape, and exine sculpturing. The seed coat ornamentation of Type I was ocellate, and pollen shape was oblate-spheroidal. While Type II was represented by reticulate seed coat and prolate-spheroidal pollen shape, Type III had tuberculate seed coat. This study revealed that both palynological and seed morphological characters are of significant importance in the taxonomy of the genus.

Pollen Morphology Of Some Gypsophila L. (Caryophyllaceae) Species And Its Taxonomic Value, Ebru Ataşlar, İsmühan Potoğlu Erkara, Süleyman Tokur

Turkish Journal of Botany

Pollen morphology of 12 taxa (6 of them endemic) that belong to the genus Gypsophila L. were investigated using light microscopy (LM), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). Differences in pollen morphology between these taxa were determined based on palynological studies. Pollen grains are spheroidal and polyporate. The exine structure is tectate, but that of G. sphaerocephala var. sphaerocephala is intectate. The exine sculpture is granulate-microechinate-microperforate, but that of G. sphaerocephala var. sphaerocephala displays clavate-microechinate ornamentation. The operculum exists in the form of scattered pieces in G. curvifolia, while it exists as a whole in the other …

Nectar Secondary Compounds Affect Self-Pollen Transfer: Implications For Female And Male Reproduction, Rebecca E. Irwin, Lynn S. Adler

Dartmouth Scholarship

Pollen movement within and among plants affects inbreeding, plant fitness, and the spatial scale of genetic differentiation. Although a number of studies have assessed how plant and floral traits influence pollen movement via changes in pollinator behavior, few have explored how nectar chemical composition affects pollen transfer. As many as 55% of plants produce secondary compounds in their nectar, which is surprising given that nectar is typically thought to attract pollinators. We tested the hypothesis that nectar with secondary compounds may benefit plants by encouraging pollinators to leave plants after visiting only a few flowers, thus reducing self-pollen transfer. We …

The Structure And Ultra Structure Of Anther Epidermis And Pollen In Lagerstroemia Indica L. (Lythraceae) In Response To Air Pollution, Farkhondeh Rezanejad

Turkish Journal of Botany

The structure of the anthers and pollen of Lagerstroemia indica L. (crepe myrtles) (Lythraceae) in samples collected from clean and polluted areas was studied by OM, SEM, and TEM. The epidermal cells of the anthers enlarged during anther development. Their cuticle content increased and became thick and folded. The cytoplasm of epidermal cells was peripheral and degenerated in mature anthers. At this time, their major content was phenolic compounds. The epidermal cells in the anthers collected from polluted areas were shrunken, fragile, and burned at the tip, compared to those collected from non-polluted areas. Flavonoid stainability was greater in the …

Inflorescence Architecture And Floral Morphology Of Aratitiyopea Lopezii (Xyridaceae), Lisa M. Campbell, Dennis Wm. Stevenson

Aliso: A Journal of Systematic and Floristic Botany

Aratitiyopea lopezii is a robust perennial species of Xyridaceae from seasonally saturated, mid- to high-elevation, sandstone and granite sites in northern South America. The species lacks the scapose inflorescence characteristic of Xyridaceae and, having the gestalt of a rhizomatous bromeliad, it is seemingly aberrant in the family. However, closer examination confirms features consistent with the family and the previously noted morphological similarities to Orectanthe. Details of inflorescence structure and floral morphology are presented and compared to other genera of Xyridaceae.

The Operculum In Pollen Of Monocotyledons, Carol A. Furness, Paula J. Rudall

Aliso: A Journal of Systematic and Floristic Botany

Within monocotyledons, monosulcate pollen is the predominant type and probably represents the plesiomorphic condition, but considerable variation occurs in sulcus morphology. An operculum is an exine thickening that covers most of an aperture. Monocot opercula are usually associated with sulci, although they can occur in ulcerate apertures, as in Poaceae. There are several other aperture types closely related to the monosulcate-operculate type, and confusion occurs in the palynological literature between monosulcate-operculate, pontoperculate, disulculate, disulcate, and zona-aperturate (zonasulculate or zonasulcate) pollen. Transmission electron microscopy (TEM) was used to determine the distribution of the thick apertural intine and to accurately identify these …

Aperture Pattern And Microsporogenesis In Asparagales, Sophie Nadot, Laurent Penet, Leanne D. Dreyer, Arlette Forchioni, Adrienne Ressayre

Aliso: A Journal of Systematic and Floristic Botany

The aperture pattern of pollen grains is a character defined as the number, shape, and position of apertures. Although this character is highly variable in angiosperms, two states are particularly widespread. Pollen grains with one polar aperture occur frequently in basal angiosperms and monocots while tricolpate pollen is a synapomorphy of the eudicots. Many morphological characters are the result of a compromise between selective forces (acting on morphology) and developmental constraints (limiting the range of possible morphologies). To investigate what are the respective roles of development and selection in the determination of aperture pattern in angiosperms, we have chosen to …

Morphological And Palynological Investigation On Silene Gigantea L. Var. Gigantea And Silene Behen L. (Caryophyllaceae) Distributed In Western Anatolia And Northern Cyprus, Kemal Yildiz

Turkish Journal of Botany

A comparative investigation was carried out on the morphology and palynology of Silene gigantea L. var. gigantea and Silene behen L. species of the family Caryophyllaceae distributed in Western Anatolia and Northern Cyprus. An examination conducted on S. gigantea var. gigantea revealed that the calyx length in Western Anatolian specimens was shorter than that of those from Northern Cyprus, that the basal petal blades of the Western Anatolian specimens did not have any ligula while those from Northern Cyprus did, and that the petal blades belonging to the specimens from Northern Cyprus demonstrated less clefting as compared to those from …

The Anatomical And Palynological Properties Of Alyssum Obtusifolium Steven Ex Dc. (Brassicaceae), Nermi̇n Orcan, Riza Bi̇nzet

Turkish Journal of Botany

Alyssum obtusifolium Steven ex DC. was explored in terms of its anatomical and palynological aspects. The root is perennial and it has alternating concentric zones of xylem with large and small vessels respectively. The number of vascular bundles is 13-15 in the stem. The leaves are isolateral and have stomata cells which are anisocytic. Both surfaces of the leaves are covered with stellate hairs. The pollen type of the specimens is tricolpate.

In Vitro Pollen Germination And Pollen Tube Characteristics In Tetraploid Red Clover (Trifolium Pratense L., H. Nurhan Büyükkartal

Turkish Journal of Botany

The morphological characteristics, fertility and in vitro germination of natural tetraploid red clover (Trifolium pratense L.) pollen were examined as well as the characteristics of pollen tubes and callose formation. Pollen grains of red clover are tricolporate and usually the germination of pollen is monosphonic. Among the pollen tubes that were formed under in vitro conditions, in addition to those that went through the normal growth process, poorly or non-grown pollen tubes were also observed. In addition, some abnormalities in the form of callose deposition were observed in the pollen tubes.

Ultraviolet-B Radiation: Effects On Pollen Of 34 Taxa, And Inheritance Patterns And Carryover Of Radiation Response In Arabidopsis, Javad Torabinejad

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Although considerable research has addressed effects of elevated ultraviolet-B (UV-8) radiation on vegetative plant structures and processes, the reproductive biology and patterns of inheritance of UV-B tolerance have received much less attention. I examined the effects of UV-B radiation on pollen of 34 taxa. I also addressed questions concerning the patterns of inheritance of UV-B tolerance in Arabidopsis thaliana and examined potential cumulative carryover effects of UV-B exposure through multiple generations of this species.

In the first study, a significant reduction in pollen germination occurred in only five species, but pollen tube growth in more than half of the species …

Adaptability Of Scanning Electron Microscopy To Studies Of Pollen Morphology, John J. Skvarla, John R. Rowley, William F. Chissoe

Aliso: A Journal of Systematic and Floristic Botany

We have explored methods to achieve excellent results in study of the pollen grain wall by using only one electron microscope, the scanning electron microscope (SEM). While the secondary electron imaging mode, the most common in use, has great value in characterizing the exine surface it is possible to obtain a more comprehensive representation of pollen grain walls by expanding the capability of the secondary mode and making use of backscatter and transmission imaging detectors. In this way information is obtained about internal exine features that are likely to be more stable phylogenetically than the generally late-to-form surface structure. We …

Pollen Of The Myricaceae - A Preliminary Report, Marshall D. Sundberg

Journal of the Minnesota Academy of Science

Pollen of 16 species and one variety of the Myricaceae was examined, including members of each of the genera proposed by Chevalier (1901) in addition to Canacomyrica (Guillaumin, 1939). Comparison of pollen characters within genera, within sections, between sections, and between genera suggests that the Myricaceae can be divided into four genera: Canacomyrica; Comptonia; Gale; and Myrica. The genus Myrica can be further divided into three sections; Cerophora, Fava, and Morella.

Limitation Studies Of Seed Set In The Onion Allium Cepa L. (Liliaceae), Nizar Shukri Shasha'a

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Two field experiments were carried out. In the first experiment, 13 variables were studied for 3 inbred groups as influenced by genetic differences, source of pollen, soil moisture, fertilizers, and size of bulbs. Path-coefficient analysis was made of various insect pollinators influencing seed yield in different inbreds, and of components of seed production in all inbreds together. In the second experiment, 4 variables were studied for one male-sterile inbred and one male-fertile inbred as influenced by soil moisture and fertilizers.

Genetic differences among inbreds were the most important source of variation in seed yields. This points out that a major …

Linkage And Inheritance Studies Involving An Annual Pollen Restorer And Other Genetic Characters In Beta Vulgaris L., Theron E. Roundy

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A pollen-restorer sugarbeet inbred, developed by four generations of selection of highly fertile plants from a CMS X table beet cross, was studied to determine if a change from sterile to fertile cytoplasm had occurred. Data showed that the fertility expressed by the restorer inbred was the result of genetic factors and not cytoplasmic reversion. Linkage tests with the R^f gene showed independence of the YRB group, m and vi₄. A yellow-leaf mutant was inherited as a simple recessive factor. A partial pollen-restorer character, found in the yellow-leaf material, was inherited as a single dominant gene. The …

Penstemon In Your Garden, R. D. Uhlinger, G. Viehmeyer

Nebraska Agricultural Experiment Station: Historical Circulars

A new race of hardy perennials is beginning to appear in American gardens. These are the penstemons, a genus of plants closely related to the familiar snapdragon, which may become important ornamentals as they be come better known to gardeners. The purpose of this bulletin is to show the possibility of the genus as an ornamental and to suggest species and species hybrids of possible value to Great Plains gardeners; to provide information about propagation and culture; and to encourage gardeners to engage in penstemon breeding as an avocation.

Early Pollen Forcing In A White X Black Spruce Hybrid And Its Parental Species, Lawson L. Winton

Journal of the Minnesota Academy of Science

Viable pollen was successfully forced from winter-collected cuttings of white and black spruce, as well as of a hybrid of them. The natural time difference in flowering was overcame, thus providing a tool for interbreeding these species. During forcing, and naturally on the trees, pollen always shed from white spruce first, then the hybrid and finally from black spruce. Using departures from long-range weather averages, a heat-requirement difference was postulated for each species to account for the time difference in their flowering.

Penstemon In Your Garden, G. Viehmeyer

Nebraska Agricultural Experiment Station: Historical Circulars

A new race of hardy perennials is beginning to appear in American gardens. These are the penstemons, a genus of plants closely related to the familiar snapdragon, which may become important ornamentals as they be come better known to gardeners. The purpose of this bulletin is to show the possibility of the genus as an ornamental and to suggest species and species hybrids of possible value to Great Plains gardeners; to provide information about propagation and culture; and to encourage gardeners to engage in penstemon breeding as an avocation.