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Pollen And Seed Morphology Of Velezia L. (Caryophyllaceae) Genus In Turkey, İlham Eröz Poyraz, Ebru Ataşlar Jan 2010

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 …


Re-Evaluated Conservation Status Of Salvia (Sage) In Turkey I: The Mediterranean And The Aegean Geographic Regions, Ferhat Celep, Musa Doğan, Ahmet Kahraman Jan 2010

Re-Evaluated Conservation Status Of Salvia (Sage) In Turkey I: The Mediterranean And The Aegean Geographic Regions, Ferhat Celep, Musa Doğan, Ahmet Kahraman

Turkish Journal of Botany

The precise evaluation of the conservation status of endemic and rare species is necessary in order to prevent their extinction. According to our current taxonomic revision of Turkish Salvia L., the Mediterranean and Aegean geographic regions of Turkey have 60 taxa, 32 of which are endemic (mainly local endemics), 5 of which are non-endemic rare, and the remaining 23 taxa are widely distributed. The rate of endemism is 53% in the area. The destruction of habitat through human encroachment such as urbanisation, land clearing, overgrazing, pollution, and road and dam constructions is the principal threat in the study area. Based …


A Taxonomic Revision Of Salvia Euphratica Sensu Lato And Its Closely Related Species (Sect. Hymenosphace, Lamiaceae) Using Multivariate Analysis, Ahmet Kahraman, Ferhat Celep, Musa Doğan, Safi Bagherpour Jan 2010

A Taxonomic Revision Of Salvia Euphratica Sensu Lato And Its Closely Related Species (Sect. Hymenosphace, Lamiaceae) Using Multivariate Analysis, Ahmet Kahraman, Ferhat Celep, Musa Doğan, Safi Bagherpour

Turkish Journal of Botany

As an initial part of a revisional study based on the genus Salvia L. (Lamiaceae), extensive field studies, herbarium and literature surveys, and multivariate analysis have been conducted on the basis of the Salvia euphratica sensu lato (S. cerino-pruinosa, S. euphratica, S. leiocalycina, and S. pseudeuphratica) and its closely related species (S. kronenburgii and S. sericeo-tomentosa) in order to understand their taxonomic status. For the multivariate analysis, 35 OTUs (Operational Taxonomic Units) representing 24 populations of the species were investigated and scored on the basis of 25 character states by means of MVSP software. Principle coordinate analysis (PCO) utilizing the …


Embryological And Cytochemical Features Of Scilla Autumnalis L., Zeynep Mi̇ne Coşkun, Meral Ünal Jan 2010

Embryological And Cytochemical Features Of Scilla Autumnalis L., Zeynep Mi̇ne Coşkun, Meral Ünal

Turkish Journal of Botany

Nucellar epidermal cells in the micropylar region of Scilla autumnalis L. differentiate into a nucellar cap. It secretes a PAS-positive exudate filling the micropyle. A group of cells at the chalazal end of the nucellus forms a hypostase. Close to the antipodals, the hypostase cells contain abundant starch grains, suggesting a function as a storage tissue. Another ovular structure is the obturator. It secretes an exudate that stains deeply with PAS reaction, and it takes a role in directing the growth of pollen tubes toward the micropyle. Cytochemical tests in the mature embryo sac indicate the presence of high amounts …


Pollination Behaviour Of Linum Aretioides Boiss. (Linaceae) And Its Relations With Air Temperature And Humidity, Özcan Seçmen, Aykut Güvensen, Serdar Gökhan Şenol, Sali̇h Gücel Jan 2010

Pollination Behaviour Of Linum Aretioides Boiss. (Linaceae) And Its Relations With Air Temperature And Humidity, Özcan Seçmen, Aykut Güvensen, Serdar Gökhan Şenol, Sali̇h Gücel

Turkish Journal of Botany

Linum aretioides Boiss., a local endemic, is distributed only on 2 mountains (İzmir: Bozdağ; Denizli: Babadağ) at the western part of Turkey between 1630 and 2300 m altitudes, above the tree line. The studies were conducted on Mount Bozdağ above the ski complex between 1750 and 2150 m, and on Mount Babadağ between 1630-2300 m both located at subalpine zones. Four 8 × 8 m quadrats on Bozdağ and 5 on Babadağ were used for the experiments. The development of reproductive structures of plants and frequency of insect visits were observed from early May to late June in 2006 and …


Morphological Character Analysis In Turkish Micromeria Benth. (Lamiaceae) Species With A Numerical Taxonomic Study, Turan Arabaci, Tuncay Di̇rmenci̇, Ferhat Celep Jan 2010

Morphological Character Analysis In Turkish Micromeria Benth. (Lamiaceae) Species With A Numerical Taxonomic Study, Turan Arabaci, Tuncay Di̇rmenci̇, Ferhat Celep

Turkish Journal of Botany

As an initial part of a revisional study based on the genus Micromeria Benth. (Lamiaceae), extensive field studies, herbarium and literature surveys, and multivariate analysis have been conducted. Recently, many morphological and molecular studies have been conducted on the genus Micromeria and related genera. Consequently, the generic boundaries of Micromeria have dramatically changed. Therefore, a morphometric analysis was carried out on Turkish Micromeria s.l. species, belonging to sect. Micromeria, sect. Cymularia Boiss., and sect. Pseudomelissa Benth., 2 Clinopodium L. species, and 2 Mentha L. species in order to understand their taxonomic relationship. For morphometric analysis, 27 morphological characters and their …


Phytosociological Structure Of Nemrut Mountain (Adıyaman/Turkey), Ahmet Zafer Tel, Adem Tatli, Ömer Varol Jan 2010

Phytosociological Structure Of Nemrut Mountain (Adıyaman/Turkey), Ahmet Zafer Tel, Adem Tatli, Ömer Varol

Turkish Journal of Botany

This investigation was carried out between 1996 and 2001 in order to research the vegetation of Nemrut Mountain, one of the most important national historical park of Anatolia, on the south-east Taurus (Adıyaman-Turkey). Vegetation studies have been carried out according to the Braun-Blanquet's method. In this study we determined 7 plant associations, 3 sub associations, and 1 plant community, all of which are syntaxa new to science, in 4 different vegetation types. Associations and its higher units are as follows: Quercetea ilicis Br.-Bl. 1947 Qercetalia ilicis Br.-Bl. 1947 Quercion calliprini Zohary 1962 1. Pistacio khynjuki-Cotinetum coggyriae ass. nova Quercetea pubescentis …


Species Composition And Diversity Of Epipelic Algae In Balık Lake (Şavşat-Artvin, Turkey), Bülent Şahi̇n, Bülent Akar, İmran Bahçeci̇ Jan 2010

Species Composition And Diversity Of Epipelic Algae In Balık Lake (Şavşat-Artvin, Turkey), Bülent Şahi̇n, Bülent Akar, İmran Bahçeci̇

Turkish Journal of Botany

The species composition and diversity of the epipelic algae of Balık Lake were investigated between May and October 2008. A total of 39 taxa were determined, and Cyclotella meneghiniana, Craticula cuspidata, Closterium strigosum, Cocconeis placentula var. euglypta, and Amphora ovalis were the most conspicuous algae, regarding frequency of occurrence and relative abundance in the epipelic algal flora. While the highest total cell number of the epipelic community was 26,214 cells/cm^2 in October, the lowest was 23,644 cells/cm^2 in July. The highest species diversity index (H^{'}) value was 2.26, in June.


Phylogenetic Relationships Of Elymus L. And Related Genera (Poaceae) Based On The Nuclear Ribosomal Internal Transcribed Spacer Sequences, Ayten Di̇zkirici, Zeki̇ Kaya, Evren Cabi̇, Musa Doğan Jan 2010

Phylogenetic Relationships Of Elymus L. And Related Genera (Poaceae) Based On The Nuclear Ribosomal Internal Transcribed Spacer Sequences, Ayten Di̇zkirici, Zeki̇ Kaya, Evren Cabi̇, Musa Doğan

Turkish Journal of Botany

To help in the clarification of the taxonomic status of Elymus L. and related genera Agropyron Gaertn., Leymus Hochst., Hordelymus (Jess.) Harz, and Brachypodium P.Beauv., the sequence diversity in the internal transcribed spacer (ITS) region of nuclear ribosomal DNA was studied. ITS data of 64 Triticeae accessions including 40 Elymus, 12 Agropyron, 7 Leymus, and 4 Hordelymus, and 1 Brachypodium as an out-group were analysed. The molecular diversity statistics indicated that the most diverse genus is Elymus among the studied genera. The constructed phylogenetic tree by the maximum parsimony method revealed that one specimen of Elymus, E. pycnanthus (Godr.) Melderis, …


Comparative Rapd Analysis And Pollen Structure Studies Of Bellis Perennis L., Nesli̇han Kavalcioğlu, Leyla Açik, Nur Münevver Pinar Jan 2010

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 …


Karyology Of Ten Turkish Trigonella L. (Leguminosae) Species From Section Cylindricae Boiss., Esra Marti̇n, Hasan Akan, Murat Eki̇ci̇, Zeki̇ Aytaç Jan 2010

Karyology Of Ten Turkish Trigonella L. (Leguminosae) Species From Section Cylindricae Boiss., Esra Marti̇n, Hasan Akan, Murat Eki̇ci̇, Zeki̇ Aytaç

Turkish Journal of Botany

This study describes the karyotypes of 10 Turkish species of Trigonella L. belonging to section Cylindricae Boiss. (Leguminosae). Excluding the karyotypes of T. velutina Boiss. and of T. sibthorpii Boiss., which were previously studied, all of the other 8 species were studied here for the first time. The species of the section were gathered from different localities in Turkey, and it was determined that the somatic chromosome numbers for all species were the same (2n = 16). Also, satellite metaphase chromosomes were determined in T. velutina and T. strangulata.


New Lichen Records From Georgia, Tzimi Inashvili, Ketevan Batsatsashvili Jan 2010

New Lichen Records From Georgia, Tzimi Inashvili, Ketevan Batsatsashvili

Turkish Journal of Botany

New records of the following 17 lichen taxa are reported from Georgia: Aspicilia esculenta (Pall.) Flagey, Caloplaca lobulata (Flörke) Hellb., Cladonia caespiticia (Pers.) Flörke, Hypogymnia farinacea Zopf, H. subduplicata (Rass.) Rass., Lecidella stigmatea (Ach.) Hertel & Leuckert, Leptorhaphis lucida Körb., Parmelia saxatilis (L.) Ach. var. divaricata Delise ex Nyl., Parmotrema arnoldii (Du Rietz) Hale, Phaeophyscia hirsuta Mereschk., Physcia biziana (A.Massal.) Zahlbr., Physconia detersa (Nyl.) Poelt, Ramalina obtusata (Arnold) Bitter, Squamarina gypsacea (Sm.) Poelt, Toninia sedifolia (Scop.) Timdal, Umbilicaria cylindrica (L.) Delise ex Duby var. tornata (Ach.) Nyl., and Xanthoparmelia tinctina (Maheu & A.Gillet) Hale. Four of the reported taxa were …


Functional Analysis Of B And C Class Floral Organ Genes In Spinach Demonstrates Their Role In Sexual Dimorphism, D Noah Sather, Maja Jovanovic, Edward M. Golenberg Jan 2010

Functional Analysis Of B And C Class Floral Organ Genes In Spinach Demonstrates Their Role In Sexual Dimorphism, D Noah Sather, Maja Jovanovic, Edward M. Golenberg

Wayne State University Associated BioMed Central Scholarship

Abstract

Background

Evolution of unisexual flowers entails one of the most extreme changes in plant development. Cultivated spinach, Spinacia oleracea L., is uniquely suited for the study of unisexual flower development as it is dioecious and it achieves unisexually by the absence of organ development, rather than by organ abortion or suppression. Male staminate flowers lack fourth whorl primordia and female pistillate flowers lack third whorl primordia. Based on theoretical considerations, early inflorescence or floral organ identity genes would likely be directly involved in sex-determination in those species in which organ initiation rather than organ maturation is regulated. In this …


Genetic Diversity Of Wheat Cultivars From Turkey And U. S. Great Plains, Anyamanee Auvuchanon Jan 2010

Genetic Diversity Of Wheat Cultivars From Turkey And U. S. Great Plains, Anyamanee Auvuchanon

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

Genetic diversity of wheat cultivars from Turkey and the Great Plains was studied under the hypothesis ‘Turkey’ wheat originated from Turkey and is the original hard red winter wheat landrace in the Great Plains. Wheat cultivars in Turkey and the Great Plains were selected for adaptation in two countries which were similar in climate. Twenty-two Turkish and twenty-three Great Plains wheat cultivars were selected for this study using SSR markers, agronomic, and end-use quality traits data. Wheat cultivars were clustered into five groups based on SSR markers and the clustering largely followed their countries of origin and pedigree. Modern Great …


A Survey Of The Vascular Flora Of Beaufort County, South Carolina, Daniel Payne Jan 2010

A Survey Of The Vascular Flora Of Beaufort County, South Carolina, Daniel Payne

All Theses

Beaufort County has historically been one of the most poorly botanized counties in the state. Geographically, it lies farther from the major research institutions than most other counties and has therefore received little attention from modern botanists. Major waterways, numerous private communities and an oppressive summer climate further complicate botanical research. Beaufort has one of the fastest growing human populations in the state. Natural areas are rapidly being converted into residential and commercial developments. An understanding of the county's flora is necessary to focus conservation efforts to preserve critical habitat and develop management plans for maintaining biodiversity. This project was …


Discovery: The Student Journal Of Dale Bumpers College Of Agricultural, Food And Life Sciences - Volume 11 2010, Several Authors Jan 2010

Discovery: The Student Journal Of Dale Bumpers College Of Agricultural, Food And Life Sciences - Volume 11 2010, Several Authors

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

No abstract provided.


Impact Of Soil Drought Stress On Photochemical Efficiency Of Photosystem Ii And Antioxidant Enzyme Activities Of Phaseolus Vulgaris Cultivars, Rabi̇ye Terzi̇, Aykut Sağlam, Ni̇hal Kutlu, Hati̇ce Nar, Asim Kadioğlu Jan 2010

Impact Of Soil Drought Stress On Photochemical Efficiency Of Photosystem Ii And Antioxidant Enzyme Activities Of Phaseolus Vulgaris Cultivars, Rabi̇ye Terzi̇, Aykut Sağlam, Ni̇hal Kutlu, Hati̇ce Nar, Asim Kadioğlu

Turkish Journal of Botany

Common bean (Phaseolus vulgaris L.) cultivars (cvs) (Göynük 98, Karacaşehir 90, Şehirali 90, ES 855, and Yunus 90) were subjected to drought stress in order to assess the levels of drought tolerance through the analysis of growth parameters, leaf water potential (\psi_{leaf}), stomatal conductance (g_s), chlorophyll (chl) content, and lipid peroxidation. Significant differences were recorded among cultivars in most traits. Yunus 90 was identified as the most tolerant, and Karacaşehir 90 was the most sensitive. Furthermore, the changes in antioxidant enzyme activities, H_2O_2 content, and Photosystem II were investigated under drought stress, where Antioxidant enzyme activities increased while H_2O_2 contents …


Enhanced Adventitious Shoot Regeneration From Aerial Stem Explants Of Ginger Using Tdz And Its Histological Studies, Adinkudikuyyal Lincy, Bhaskaran Sasikumar Jan 2010

Enhanced Adventitious Shoot Regeneration From Aerial Stem Explants Of Ginger Using Tdz And Its Histological Studies, Adinkudikuyyal Lincy, Bhaskaran Sasikumar

Turkish Journal of Botany

A protocol for direct plantlet regeneration from aerial stem explants of ginger (Zingiber officinale Rosc.) has been developed. Adventitious shoots and roots were regenerated from in planta aerial stem explants of 2 ginger varieties viz. var. 'Jamaica' and var. 'Varada'. Maximum shoot and root regeneration were observed in the cultures containing TDZ and IBA (1:1; 1:0.1 mg L-1) in both varieties. Cultures containing TDZ alone showed poor shoot and root formation. Histological studies revealed that the shoot initials originated from the primary thickening meristem and apical meristem, while the root primordial originated from the primary thickening meristem present in the …


The Genotoxic Potential Of Two Heavy Metals In Inbred Lines Of Maize (Zea Mays L.), Girjesh Kumar, Prashant Kumar Rai Jan 2010

The Genotoxic Potential Of Two Heavy Metals In Inbred Lines Of Maize (Zea Mays L.), Girjesh Kumar, Prashant Kumar Rai

Turkish Journal of Botany

The genotoxic effects of 2 heavy metals (mercury chloride and cadmium chloride) on the gametic cells of 6 inbred lines of maize were tested in terms of cytological abnormalities. Meiosis was normal under control conditions. During the treatments with mercury and cadmium there was a concentration-dependent increase in meiotic abnormalities in all the inbred lines. A wide spectrum of chromosomal aberrations in the treated sets was stickiness, followed by laggards, bridges, scattering, precocious movement, fragments, etc. Maximum chromosomal anomalies were observed in inbred line CM-142 in both the treatment sets of heavy metals. Compared to CdCl_2, HgCl_2 induced more chromosomal …


A New Species Of Onosma (Boraginaceae) From Eastern Turkey, Ali̇ Kandemi̇r, Zafer Türkmen Jan 2010

A New Species Of Onosma (Boraginaceae) From Eastern Turkey, Ali̇ Kandemi̇r, Zafer Türkmen

Turkish Journal of Botany

Onosma beyazoglui Kandemir & Z. Türkmen sp. nov. (Boraginaceae) is described as a new species from the province of Erzincan in Turkey. Diagnostic morphological characters of this new species from the related species are discussed.


Nitrogen And Phosphorus Resorption In A Salt Marsh In Northern Turkey, Yasemi̇n Çakir, Tuğba Özbucak, Hamdi̇ Güray Kutbay, Dudu Duygu Kiliç, Ali̇ Bi̇lgi̇n, Rena Huseyinova Jan 2010

Nitrogen And Phosphorus Resorption In A Salt Marsh In Northern Turkey, Yasemi̇n Çakir, Tuğba Özbucak, Hamdi̇ Güray Kutbay, Dudu Duygu Kiliç, Ali̇ Bi̇lgi̇n, Rena Huseyinova

Turkish Journal of Botany

This study was conducted to investigate foliar nitrogen and phosphorus dynamics, nitrogen and phosphorus resorption, and some leaf traits (i.e. SLA=specific leaf area) in some coastal salt marsh plants located in northern Turkey. The study area is located on the east bank of the Kızılırmak River in the central Black Sea Region. There were statistically significant differences among months (from June to October) in terms of SLA in all species except for Artemisia santonicum. However, no significant differences were found with respect to P in all species. The highest N and P resorption efficiencies were found in Salicornia prostrata, whereas …


Development Of A Highly Responsive Leaf-Based Regeneration System For Peperomia Species, Mohammad Ahmadabadi, Ralph Bock Jan 2010

Development Of A Highly Responsive Leaf-Based Regeneration System For Peperomia Species, Mohammad Ahmadabadi, Ralph Bock

Turkish Journal of Botany

Several species in the genus Peperomia Ruiz & Pav. have giant chloroplasts in the palisade parenchyma of their leaves. Because of this unique feature, Peperomia metallica L. Linden & Rodigas has become a valuable model plant for studying plastid biology. However, the use of Peperomia for molecular studies has been limited by the lack of efficient regeneration and transformation protocols. In this work, we aimed to develop a reliable regeneration system for Peperomia from leaf explants. Using MS medium complemented with different combinations of phytohormones, a highly efficient in vitro regeneration protocol was developed for P. metallica and P. peduncularis, …


Macrofungi Of Derebucak District (Konya, Turkey), Si̇nan Alkan, Giyasetti̇n Kaşik, Si̇nan Aktaş Jan 2010

Macrofungi Of Derebucak District (Konya, Turkey), Si̇nan Alkan, Giyasetti̇n Kaşik, Si̇nan Aktaş

Turkish Journal of Botany

Macrofungi specimens were collected from different localities in Derebucak district (Konya province) between 2005 and 2007, particularly during the autumn and spring. As a result 134 species were identified. Thirteen of them belong to Ascomycota, and the other 121 belong to the division Basidiomycota. According to the present literature about the macrofungi of Turkey, 6 taxa are new records for Turkey. These are Lachnellula calyciformis (Willd.) Dharne of the division Ascomycota, and Hebeloma stenocystis J.Favre, Cortinarius calochrous var. coniferarum (M.M.Moser) Nezdojm., Cortinarius cupreorufus Brandrud, Inocybe ayeri Furrer-Ziogas, and Calocera pallidospathulata D.A.Reid of the division Basidiomycota.


Male Individuals In Cultivated Fritillaria Persica L. (Liliaceae): Real Androdioecy Or Gender Disphasy?, Elisa Mancuso, Lorenzo Peruzzi Jan 2010

Male Individuals In Cultivated Fritillaria Persica L. (Liliaceae): Real Androdioecy Or Gender Disphasy?, Elisa Mancuso, Lorenzo Peruzzi

Turkish Journal of Botany

In the last twenty years the growing number of studies about the reproductive biology in angiosperms has brought to light new cases of andromonoecy and androdioecy, the rarest sexual models among flowering plants. Female-sterile sexual systems, especially within order Liliales and family Liliaceae, often seem to occur in the particular form of size/age dependent sex allocation, known as "gender disphasy". The presence of male individuals of Fritillaria persica (Liliaceae) is here documented. Comparative morphological and functional sexual expression of this species, among males and hermaphrodites, was investigated by means of flowers counting, morphometric measurements of plants and pollen-grains, pollen viability …


A New Species Of Echinops (Asteraceae) From Turkey, Cem Vural, Mustafa Kemal Bi̇ter, Mehmet Yaşar Dadandi Jan 2010

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.


Carbon Dynamics In A Phragmites Australis Invaded Riparian Wetland, Steven Walters Jan 2010

Carbon Dynamics In A Phragmites Australis Invaded Riparian Wetland, Steven Walters

School of Natural Resources: Dissertations, Theses, and Student Research

Invasive plant species are widely recognized as a major threat to biodiversity and ecosystem stability. Wetland ecosystems tend to be much more susceptible to invasions because of their location on the landscape where water, nutrients, and the impacts of disturbances accumulate. Invasive plants have the ability to alter ecosystem processes and community/population dynamics. The ability of invasive plants to alter these processes can have profound economic consequences. In the United States, control of invasive wetland species alone costs approximately 155 million dollars annually. The state of Nebraska spends 2 million dollars annually controlling invasive plant species in the Platte River …


Yield Potential And Resource-Use Efficiency Of Maize Systems In The Western U. S. Corn Belt, Patricio Grassini Jan 2010

Yield Potential And Resource-Use Efficiency Of Maize Systems In The Western U. S. Corn Belt, Patricio Grassini

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

Maize demand for food, livestock feed, and biofuel is expected to increase substantially. The Western U.S. Corn Belt accounts for 23% of U.S. maize production, and irrigated maize accounts for 43 and 58% of maize land area and total production, respectively, in this region. The most sensitive parameters (yield potential [YP], water-limited yield potential [YP-W], yield gap between actual yield and YP, and resource-use efficiency) governing performance of maize systems in the region are lacking. A simulation model was used to quantify YP under irrigated and rainfed conditions based on weather data, soil properties, and crop management at 18 locations. …


Estimation Of Effective Plant Area Index For South Korean Forests Using Lidar System, D. A. Kwak, W. K. Lee, Menas Kafatos, Y. Son, H. K. Cho, S. H. Lee Jan 2010

Estimation Of Effective Plant Area Index For South Korean Forests Using Lidar System, D. A. Kwak, W. K. Lee, Menas Kafatos, Y. Son, H. K. Cho, S. H. Lee

Mathematics, Physics, and Computer Science Faculty Articles and Research

Light Detection and Ranging (LiDAR) systems can be used to estimate both vertical and horizontal forest structure. Woody components, the leaves of trees and the understory can be described with high precision, using geo-registered 3D-points. Based on this concept, the Effective Plant Area Indices (PAIe) for areas of Korean Pine (Pinus koraiensis), Japanese Larch (Larix leptolepis) and Oak (Quercus spp.) were estimated by calculating the ratio of intercepted and incident LIDAR laser rays for the canopies of the three forest types. Initially, the canopy gap fraction (GLiDAR) was generated by extracting the LiDAR data reflected from the canopy surface, or …


A Taxonomic Revision Of Orthotrichaceae (Musci) With Contributions To The Biosystematics Of Macromitrium Brid. In Malaysia., Yong Kien Thai Jan 2010

A Taxonomic Revision Of Orthotrichaceae (Musci) With Contributions To The Biosystematics Of Macromitrium Brid. In Malaysia., Yong Kien Thai

Student Works (2010-2019)

Macromitrium (Orthotrichaceae) is a large genus variously divided into infrageneric groups by different authors, resulting in a complex classification which has not included many Malaysian species. This study reviews the taxonomy of Malaysian taxa and extent of morphological variation in relation to the type group. A molecular phylogenetic study was carried out to determine if Malaysian Macromitrium species represented a homogeneous taxonomic grouping. A cladistic analysis of morphological characteristics was attempted for identifying well-defined groups and their key character states. Molecular studies included Maximum Parsimony and Bayesian Inference analyses of two chloroplast DNA regions (rps4 gene and trnL-trnF interspecific region) …


Taxonomy And Biogeography Of Sundaland Gardenia (Rubiaceae)., Low Yee Wen Jan 2010

Taxonomy And Biogeography Of Sundaland Gardenia (Rubiaceae)., Low Yee Wen

Student Works (2010-2019)

In Southeast Asia, the genus Gardenia J.Ellis (Rubiaccae) is poorly understood and documented due to a lack of country revisions, contentious species delimitations and accumulation of poorly identified material in herbaria. This study reviewed the taxonomic history and position of the genus, and revised the taxonomy of Sundaland species (including those of Sumatra. the Malay Peninsula, Java_ Borneo, Palawan and adjacent islands). It includes a survey and cladistic study of morphological characteristics, and phylogenetic ana lyses using two chloroplast regions (atpB-rbcL and trnT-F) and the nuclear ITS region of representative species from Sundaland and adjoining regions. Twelve species are native …