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Genetic Control Of Self-Incompatibility In Centromadia (Hemizonia) Pungens Subsp. Laevis (Madiinae, Asteraceae), Elizabeth A. Friar, Tasha Ladoux Jan 2002

Genetic Control Of Self-Incompatibility In Centromadia (Hemizonia) Pungens Subsp. Laevis (Madiinae, Asteraceae), Elizabeth A. Friar, Tasha Ladoux

Aliso: A Journal of Systematic and Floristic Botany

The presence of self-incompatibility was tested in Centromadia pun gens subsp. laevis and the genetic basis of the self-incompatibility response was explored using crossing studies. We performed full diallel crossing experiments among 10 individuals from one natural population and four F1 families. We observed a strong self-incompatibility response in all individuals tested, with a significant difference in seed set between selfed and outcrossed matings. Most pairwise matings among parental plants were compatible, with some nonreciprocally incompatible matings (i.e., the matings were successful in one direction, but not the other), and only one reciprocally incompatible mating. The full diallel crossing …


The Chromosome Number Of Schaffnerella Gracilis (Gramineae, Chloridoideae), J. Travis Columbus, Nancy F. Refulio-Rodriguez Jan 2002

The Chromosome Number Of Schaffnerella Gracilis (Gramineae, Chloridoideae), J. Travis Columbus, Nancy F. Refulio-Rodriguez

Aliso: A Journal of Systematic and Floristic Botany

The first ever chromosome report for the monotypic genus Schaffnerella (Grarnineae, Chloridoideae) is 2n = 20 (10 II) from pollen parent cells at diakinesis, which indicates diploidy and a base number of 10. The close relative Lycurus likewise has x = 10, but is tetraploid (2n = 4x = 40).


Contents 21(2) Jan 2002

Contents 21(2)

Aliso: A Journal of Systematic and Floristic Botany

No abstract provided.


Checklist Of The Pteridophytes Of Aguascalientes, Mexico, María Elena Siqueiros-Delgado, Gabriel González-Adame Jan 2002

Checklist Of The Pteridophytes Of Aguascalientes, Mexico, María Elena Siqueiros-Delgado, Gabriel González-Adame

Aliso: A Journal of Systematic and Floristic Botany

Ferns and fern allies from Agu ascalientes, Mexico were s tudied. Fifty-five localities distributed in all municipios of the state were surveyed. Seventy-seven taxa were found: seventy species of ferns, five species of Selaginell, one species of Equisetum, and one species of Isoëtes. Forty taxa are new records for Aguascalientes. Among the ferns, Cheilanthes and Polypodium are the most diverse and abundant genera, usually occurring in xerophytic associations or dry forests. Selaginella is also common in Aguascalientes, and inhabits rocky cliffs in dry environments. Equisetum and lsoëtes are restricted to marshy places.


Developmental Failure And Loss Of Reproductive Capacity As A Factor In Extinction: A Nine-Year Study Of Dedeckera Eurekensis (Polygonaceae), Delbert Wiens, Loreen Allphin, Donald H. Mansfield, Glenn Thackray Jan 2002

Developmental Failure And Loss Of Reproductive Capacity As A Factor In Extinction: A Nine-Year Study Of Dedeckera Eurekensis (Polygonaceae), Delbert Wiens, Loreen Allphin, Donald H. Mansfield, Glenn Thackray

Aliso: A Journal of Systematic and Floristic Botany

Many long-lived perennial species exhibit lowered reproductive capacity. Early studies of reproductive success in Dedeckera eurekensis (Polygonaceae) demonstrated that the species exhibited extremely low reproductive success, low seed/ovule (S/O) ratios (i.e., the percentage of ovules that produce filled seeds; 2.5 %), low germinability of filled seeds (3.5%), low seedling survivorship (11 .1%), and lack of recruitment in natural populations. These results were attributed to genetic load, but this elicited controversy, prompting long-term studies of the relationship between the S/O ratio and environment. After nine years of monitoring, however, the S/O ratio had not changed significantly (2 .7%), and there was …


The History Of The Discovery And Initial Seed Dissemination Of Metasequoia Glyptostroboides, A "Living Fossil", Jinshuang Ma Jan 2002

The History Of The Discovery And Initial Seed Dissemination Of Metasequoia Glyptostroboides, A "Living Fossil", Jinshuang Ma

Aliso: A Journal of Systematic and Floristic Botany

Ever since the "living fossil ", Metasequoia glyptostroboides, was discovered during the 1940s in China, accounts of its mysterious discovery and introduction throughout the world have been told many times in different languages. However, information has often departed considerably from the true story. This paper represents a synthesis of more than 1000 original letters, manuscripts and publications both in Chinese and other languages, and addresses two main questions about details of the story: (1) how was the living fossil really discovered , and (2) who introduced the seeds into the U.S.A. and the rest of the world? Several controversies surrounding …


Letter From The Dean, Gregory J. Weidemann Jan 2002

Letter From The Dean, Gregory J. Weidemann

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

No abstract provided.


Instructions For Authors, Discovery Editors Jan 2002

Instructions For Authors, Discovery Editors

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

No abstract provided.


Wood And Bark Anatomy Of Myricaceae: Relationships, Generic Definitions, And Ecological Interpretations, Sherwin Carlquist Jan 2002

Wood And Bark Anatomy Of Myricaceae: Relationships, Generic Definitions, And Ecological Interpretations, Sherwin Carlquist

Aliso: A Journal of Systematic and Floristic Botany

Wood anatomy of the single species of Canacomyrica (hitherto not studied) shows that it belongs in Myricaceae, although it differs from other genera in several respects (axial parenchyma grouped in bands or columns as well as diffuse; Heterogeneous Type I rays; more numerous bars per perforation plate). The latter two features are primitive for the family. The four genera (Canacomyrica. Comptonia, Morella, and Myrica s.s.) differ from each other not only by qualitative features but by quantitative features (feature means in genera mostly non- overl apping). Wood of Comptonia and Myri ca s.s. lacks chambered crystals in axial parenchyma and …


New Species Of Phoradendron (Viscaceae) From Mexico And Guatemala And A Synopsis Of Species In Section Pauciflorae, Delbert Wiens, Frank Hawksworth Jan 2002

New Species Of Phoradendron (Viscaceae) From Mexico And Guatemala And A Synopsis Of Species In Section Pauciflorae, Delbert Wiens, Frank Hawksworth

Aliso: A Journal of Systematic and Floristic Botany

As presently interpreted Phoradendron section Paucifiorae consists of 15 species. These mistletoes parasitize primarily conifers. We describe seven new species, make status changes for four species, and provide information on the hosts and distribution of all members of the section. New species described are: Phoradendron abietinurn Wiens, on Abies durangensi s in Chihuahua, Durango, and Jalisco, Mexico; P. acuminatum Wiens, on Cupressus lusitanica in Guatemala; P. flavomarginatum Wiens, on Juniperus fiaccida in Nuevo León, Mexico; P. lta wksworthii Wiens, on Juniperus in New Mexico, west Texas, and Coahuila, Mexico; P. olivae Wiens, on Cupressus lusitanica in Colima and Jalisco, Mexico; …


Native Plants: The Preservation And Restoration Of Native Plants In Designed Landscapes In Northwest Arkansas, Janet Coleman Jan 2002

Native Plants: The Preservation And Restoration Of Native Plants In Designed Landscapes In Northwest Arkansas, Janet Coleman

Inquiry: The University of Arkansas Undergraduate Research Journal

A decline in Northwest Arkansas's native plant population has occurred over the past 50 years, as documented by the U.S. Forest Service in the Ozark-Ouachita Highlands Assessment. This decline has been caused by increased human development in natural areas and the replacement of native plants with exotic, non-native plants. As a result, a generation has grown up not knowing what an Ozark wake Robin trillium (Trillium pusillum var. ozarkanum) or Blood root (Sanguinaria canadensis) Look like, because these plants are difficult to find in nature, are not commonly grown in designed landscapes, and are Largely unavailable in garden centers. The …


Checklist Of Major Plant Species In Ashley County, Arkansas Noted By General Land Office Surveyors, Don C. Bragg Jan 2002

Checklist Of Major Plant Species In Ashley County, Arkansas Noted By General Land Office Surveyors, Don C. Bragg

Journal of the Arkansas Academy of Science

The original General Land Office (GLO) survey notes for the Ashley County, Arkansas, area were examined to determine the plant taxa mentioned during the 1818 to 1855 surveys. While some challenges in identifying species were encountered, at least 39 families and approximately 100 species were identified with reasonable certainty. Most references were for trees used to witness corners or lines. Prominent arboreal genera recorded in these early survey records included Quercus, Pinus, Carya, Liquidambar, Nyssa, Ulmus, Acer, Fraxinus, and Taxodium. A number of shrubs, vines, graminoids, and herbaceous species were also reported, including notable genera like Vaccinium, Lindera, Crataegus, Myrica, …


Effects Of Systemic Fungicides On Protein, Carbohydrate, Amino Acids And Phenolic Contents Of Susceptible (Mexipak) And Resistant (Povan) Varieties Of Triticum Aestivum L., Zamin Shaheed Siddiqui, Soaliha Ahmed Jan 2002

Effects Of Systemic Fungicides On Protein, Carbohydrate, Amino Acids And Phenolic Contents Of Susceptible (Mexipak) And Resistant (Povan) Varieties Of Triticum Aestivum L., Zamin Shaheed Siddiqui, Soaliha Ahmed

Turkish Journal of Botany

Changes in total protein, carbohydrate, phenolic content and ninhydrine positive amino acids of susceptible (MexiPak) and resistant (Povan) varieties of wheat were studied. Application of systemic fungicides caused a significant (P


Contents, Discovery Editors Jan 2002

Contents, Discovery Editors

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

No abstract provided.


Extraction Of Silymarin Compounds From Milk Thistle (Silybum Marianum) Seed Using Hot, Liquid Water As The Solvent, J. F. Alvarez Barreto, D. Julie Carrier, E. C. Clausen Jan 2002

Extraction Of Silymarin Compounds From Milk Thistle (Silybum Marianum) Seed Using Hot, Liquid Water As The Solvent, J. F. Alvarez Barreto, D. Julie Carrier, E. C. Clausen

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

High-value specialty chemicals are usually obtained from natural products by extracting with generally regarded as safe (GRAS) solvents. Because organic solvents are quite often used, high operating and disposal costs occur. When compared to traditional solvents, water is an interesting alternative because of its low operating and disposal costs. Milk thistle contains compounds (taxifolin, silychristin, silydianin, silybinin A, and silybinin B) that display hepatoxic protection properties. This paper examines the batch extraction of silymarin compounds from milk thistle seed meal in 50°C, 70°C, 85°C and 100°C water as a function of time. For taxifolin, silychristin, silybinin A, and silybinin B, …


Discovery: The Student Journal Of Dale Bumpers College Of Agricultural, Food And Life Sciences - Volume 3 2002, Several Authors Jan 2002

Discovery: The Student Journal Of Dale Bumpers College Of Agricultural, Food And Life Sciences - Volume 3 2002, Several Authors

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

No abstract provided.


Auxin (Indole-3-Acetic Acid), Gibberellic Acid (Ga_3), Abscisic Acid (Aba) And Cytokinin (Zeatin) Production By Some Species Of Mosses And Lichens, Nuray Ergün, Şaban Fati̇h Topcuoğlu, Ati̇lla Yildiz Jan 2002

Auxin (Indole-3-Acetic Acid), Gibberellic Acid (Ga_3), Abscisic Acid (Aba) And Cytokinin (Zeatin) Production By Some Species Of Mosses And Lichens, Nuray Ergün, Şaban Fati̇h Topcuoğlu, Ati̇lla Yildiz

Turkish Journal of Botany

In this study, the levels of endogenous free, bound and total auxin (Indole-3-acetic acid, IAA), gibberellic acid (GA_3), abscisic acid (ABA) and cytokinin (zeatin) were examined in some species of mosses and lichens. For determination of the levels of these plant growth regulators, spectrophotometry was used. Our findings show that the mosses and lichens used in this study produce the plant growth regulators IAA, GA_3, ABA and zeatin.


A Contribution To The Bryophyte Flora Of Western Turkey: The Bryophyte Flora Of Madran Mountain And The Çine Valley (Aydın, Turkey), Adnan Erdağ Jan 2002

A Contribution To The Bryophyte Flora Of Western Turkey: The Bryophyte Flora Of Madran Mountain And The Çine Valley (Aydın, Turkey), Adnan Erdağ

Turkish Journal of Botany

This study presents a survey on the bryophyte flora of Madran mountain and Çine valley (Aydın, Turkey). One hundred and thirty-three bryophyte species belonging to 35 families and 69 genera were recorded from the area. Phaeoceros laevis (L.) Prosk. is the only member of the hornworts while liverworts are represented by 15 species. The remaining 117 taxa belong to the Bryopsida. Thirty-five species are new records for square C11 according to Henderson's (1961) grid system.


Selected Chemical Constituents And Their Seasonal Variations In Flabellia Petiolata (Turra) Nizam. And Halimeda Tuna (Ellis & Sol.) J.V.Lamour. In The Gulf Of Antalya (North-Eastern Mediterranean), Şengül Bi̇lgi̇n, Ö. Osman Ertan Jan 2002

Selected Chemical Constituents And Their Seasonal Variations In Flabellia Petiolata (Turra) Nizam. And Halimeda Tuna (Ellis & Sol.) J.V.Lamour. In The Gulf Of Antalya (North-Eastern Mediterranean), Şengül Bi̇lgi̇n, Ö. Osman Ertan

Turkish Journal of Botany

Seasonal changes in selected chemical, ecological and morphological characteristics of Flabellia petiolata (Turra) Nizam. and Halimeda tuna (Ellis & Sol.) J.V.Lamour., which are commonly found in the Gulf of Antalya, were studied. Crude protein content of F. petiolata was found to be higher than that of H. tuna, whereas the crude fat contents of the two species were similar. On the other hand, compared to F. petiolata, H. tuna was rich in inorganic material. Both species were observed to be dense on a seasonal basis in the sampling area and they reached their maximum length during summer.


Phytoplankton Species' Succession And Nutrients In The Southern Black Sea (Bay Of Sinop), Muhammet Türkoğlu, Tufan Koray Jan 2002

Phytoplankton Species' Succession And Nutrients In The Southern Black Sea (Bay Of Sinop), Muhammet Türkoğlu, Tufan Koray

Turkish Journal of Botany

The succession, annual cycle and diversity of phytoplankton species and seasonal changes in nutrients in the southern Black Sea (around Sinop peninsula) were investigated between August 1995 and July 1996. One species of Cyanophyceae, 83 taxa of Dinophyceae, 1 species of Prymnesiophyceae, 5 taxa of Dictyochophyceae, 88 taxa of Bacillariophyceae and 1 species of Euglenophyceae were identified. A list of phytoplankton species together with annual variations was prepared. Changes in community structure, density and diversity are discussed in relation to the physico-chemical features of the water column.


Perilla: A New Genus For Turkey, Ali̇ Arslan Dönmez Jan 2002

Perilla: A New Genus For Turkey, Ali̇ Arslan Dönmez

Turkish Journal of Botany

Perilla frutescens (L.) Britton (Labiatae), recently collected in Artvin, is a new record for the flora of Turkey. An illustration and description are given.


Changes In Abscisic Acid And Indole-3-Acetic Acid Concentrations In Funalia Trogii (Berk.) Bondartsev & Singer And Phanerochaete Chrysosporium Burds. Me446 Subjected To Salt Stress, Serpi̇l Ünyayar Jan 2002

Changes In Abscisic Acid And Indole-3-Acetic Acid Concentrations In Funalia Trogii (Berk.) Bondartsev & Singer And Phanerochaete Chrysosporium Burds. Me446 Subjected To Salt Stress, Serpi̇l Ünyayar

Turkish Journal of Botany

Variations in abscisic acid (ABA) and indole-3-acetic acid (IAA) concentrations were studied in Funalia trogii (Berk.) Bondartsev & Singer and Phanerochaete chrysosporium Burds. ME446 subjected to salt stress. The levels of ABA and IAA were determined by gas chromatography (GC) and UV-VIS spectrophotometry. The levels of hormones vary in the regulation of growth and in response to stress. It was found that ABA concentrations were higher in the salt stressed groups than in the control groups, whereas IAA concentrations were lower. These results show that, in fungi, ABA concentrations are positively and IAA concentrations negatively correlated with salt stress.


An Experimental Approach To Examining The Effect Of Water Depth And Lemna Minor L. On Algal Growth, Hani̇fe Özbay Jan 2002

An Experimental Approach To Examining The Effect Of Water Depth And Lemna Minor L. On Algal Growth, Hani̇fe Özbay

Turkish Journal of Botany

In order to test how both water depth and Lemna minor L. affect the growth rate of algae, two different experiments were designed. In the first experiment, Scenedesmus quadricauda (Turp.) Breb. was cultured in sterilized Steinberg solution with reduced N and P levels in plastic containers at depths of 5, 10, 15 and 20cm. At the end of the experiment, differences in algal growth with depth were found to be significant between a) 5 cm with 10 cm, 15 cm and 20 cm, and b) 10 cm with 15 and 20 cm depth treatments (p


Seasonal Variations In The Biomass Of Macro-Algal Communities From The Gulf Of Antalya (North-Eastern Mediterranean), İsmai̇l İbrahi̇m Turna, Ö. Osman Ertan, Mario Cormaci, Giovanni Furnari Jan 2002

Seasonal Variations In The Biomass Of Macro-Algal Communities From The Gulf Of Antalya (North-Eastern Mediterranean), İsmai̇l İbrahi̇m Turna, Ö. Osman Ertan, Mario Cormaci, Giovanni Furnari

Turkish Journal of Botany

In this study, the seasonal variations in the macro-algal biomass in the Gulf of Antalya (north-eastern Mediterranean) were investigated. The seasonal variations of the macro-algal biomass were found to be related to the biology of the abundant species during less favourable seasons. These variations occurred usually as a result of a significant reduction in algal density [Padina pavonica (L.) J.V.Lamour., Dasycladus vermicularis (Scopoli) Krasser, Chondrophycus papillosus (C.Agardh) Garbay & Harper] or loss of major part of their thallus [Cystoseira spp., Liagora distenta (Mertens ex Roth) J.V.Lamour., Liagora viscida (Forssk.) C.Agardh]. The highest values of biomass were found to be in …


\Alpha -Difluoromethylornithine Inhibits The Growth Of Fungus Macrophomina Phaseoli, Narçin Palavan Ünsal, Ayşin Çotuk, Yeşi̇m Kalaç Martini Jan 2002

\Alpha -Difluoromethylornithine Inhibits The Growth Of Fungus Macrophomina Phaseoli, Narçin Palavan Ünsal, Ayşin Çotuk, Yeşi̇m Kalaç Martini

Turkish Journal of Botany

\alpha -Difluoromethylornithine (DFMO), a specific enzyme activated inhibitor of ornithine decarboxylase (ODC), significantly inhibited the mycelial growth of the fungus Macrophomina phaseoli (Tassi) Goidanich. Putrescine (Put), when added to the nutrient medium at a concentration of 0.25 mM, decreased the inhibitory effect of DFMO. These results suggest that polyamines (PAs) are essential for the growth of fungi and that DFMO is applicable to the alleviation or prevention of crop losses due to phytopathogenic fungi.


Two New Alchemilla L. (Rosaceae) Records For The Flora Of Turkey, Sema Hayirlioğlu Ayaz, Osman Beyazoğlu Jan 2002

Two New Alchemilla L. (Rosaceae) Records For The Flora Of Turkey, Sema Hayirlioğlu Ayaz, Osman Beyazoğlu

Turkish Journal of Botany

Two Alchemilla L. (Rosaceae) species from north-east Anatolia are described as new records for Turkey.


Plant Biotechnology I, Tissue Culture And Its Applications, Kemal Kazan Jan 2002

Plant Biotechnology I, Tissue Culture And Its Applications, Kemal Kazan

Turkish Journal of Botany

No abstract provided.


The Planktonic Diatoms Of Lake Çıldır (Ardahan-Turkey), Aydin Akbulut, Kazim Yildiz Jan 2002

The Planktonic Diatoms Of Lake Çıldır (Ardahan-Turkey), Aydin Akbulut, Kazim Yildiz

Turkish Journal of Botany

This paper describes the planktonic diatom flora of Lake Çıldır. Samples were collected monthly between May 1991 and September 1993 at three different stations. A total of 94 diatom taxa were identified. In the study period, the most dominant and abundant taxa were Cyclotella meneghiniana Kütz., Aulacoseria granulata (Ehrenb.) Simonsen, Melosira varians C.Agardh and Navicula Bory spp. The diatom flora of the lake is rich in species and varieties and is similar to that in other parts of Turkey.


Phytoplankton Distribution, Diversity And Nutrients At The North-Eastern Mediterranean Coast Of Turkey (Karataş-Adana), Sevi̇m Polat, Oya Işik Jan 2002

Phytoplankton Distribution, Diversity And Nutrients At The North-Eastern Mediterranean Coast Of Turkey (Karataş-Adana), Sevi̇m Polat, Oya Işik

Turkish Journal of Botany

Seasonal changes in phytoplankton composition and phytoplankton abundance and physico-chemical factors affecting these parameters were investigated in this study. Quantitative and qualitative phytoplankton and nutrient analysis were carried out between 1998 and 1999 at 12 sampling stations located from inshore to offshore of Karataş, situated in the north-eastern Mediterranean. A total of 135 taxa were determined, belonging to four algae classes: Cyanophyceae, Bacillariophyceae, Dinophyceae and Dictyochophyceae. Bacillariophyceae appeared to be the dominant group in terms of total species number and cell numbers during the research period. The number of phytoplankton species was high in winter and quite low in summer. …


The Moss Flora Of Ankara - Kızılcahamam - Çamkoru And Çamlıdere Districts, Barboros Çeti̇n, Egemen Unç, Güray Uyar Jan 2002

The Moss Flora Of Ankara - Kızılcahamam - Çamkoru And Çamlıdere Districts, Barboros Çeti̇n, Egemen Unç, Güray Uyar

Turkish Journal of Botany

In this study carried out in Ankara-Kızılcahamam Çamlıdere and Çamkoru districts, 82 taxa were identified by the authors. These belong to 20 families and 42 genera of bryophytes. of these, 10 taxa are new for the A2 grid-square adopted by Henderson.