bluuebunny/crossref_metadata_2025_split huggingface dataset:
EVIDENCE A PHOTOPROTECTIVE FOR SECONDARY CAROTENOIDS OF SNOW ALGAE1
Authors: Bidigare Robert. R. , Ondrusek Michael E. , Kennicutt Mahlon C. , Iturriaga Rodolfo , Harvey H. Rodger , Hoham Ronald W. , Macko Stephen. A. 
Published: August 2006

ABSTRACTSnow algae occupy a unique habitat in high altitude and polar environments. These algae are often subject to extremes in nutrient availability, acidity, solar irradiance, desiccation, and ambient temperature. This report documents the accumulation of secondary carotenoids by snow algae in response to the availability of nitrogenous nutrients. Unusually large accumulations of astaxanthin esters in extra‐chloroplastic lipid globules produce the characteristics red pigmentation typical of some snow algae (e.g. Chlamydomonas nivalis (Bauer) Wille). Consequently these compounds greatly reduce the amount of light available for absorption by the light‐harvesting pigment‐protein complexes, thus potentially limiting photoinhibition and photodamage caused by intense solar radiation. The esterification of astaxnthin with fatty acids represents a possible mechanism by which this chromophore can be concentrated within cytoplasmic globules to maximize its photoprotective efficiency.
THE FINE STRUCTURE AND SCALE FORMATION OF CHRYSOLEPIDOMONAS DENDROLEPIDOTA GEN. ET. SP. NOV.(CHRYSOLEPIDOMONADACEAE FAM. NOV., CHRYSOPHYCEAE)1
Authors: Peters Michael C. , Andresen Robert A. 
Published: August 2006

ABSTRACT Chrysolepidomonas gen. nov. is described for single‐celled monads with two flagella, a single chloroplast, and distinctive canistrate and dendritic scales. The type species, Chrysolepidomonas dendrolepidota sp. nov., is described for the first time. The canistrate scales bear eight “bumps” on the top surface, and the dendriticscales have a tapered base with a quatrifid tip. These organic scales are formed in the Golgi apparatus and storred in a scale reservoir. The scale reservoir is bounded on two sides by the R1 and R2 in microtubular roots of the basal apparatus. The cyst (=stomatocyst, statospore) forms endogenously by means of a silica deposition vesicle. The outer cyst surface is smooth, and the pore region is unornamented. Two other organisms bearing canistrate and dendritic scales, previously assigned to the genus Sphaleromants, are transferred to the genus Chrysolepidomonas. They are C.angalica sp. nov. and C. marine(Pienaar) comb. nov. The distinguishing features of Chrysolepidomonas and Sphaleromantis are discussed. A new family, Chrysolepidomonadceae fam. noc., is described for flagellates covered with organic scales.
RHYTHMIC SETTLING BEHAVIOR IN PYRAMIMONAS PARKEAE (PRASINOPHYCEAE)1
Authors: Griffin Neil J. , Aken Mark E. 
Published: August 2006

ABSTRACTPyramimonas parkeae Norris et Pearson was examined for evidence of a settling rhythm while growing in laboratory culture. The alga settled rhythmically in a diet cycle when kept in a regularly alternating light‐dark cycle. Cells moved out of suspension when settling and attached themselves to the sides and base of the culture vessel. Although rhythmic settling was inhibited in constant dim light (LL), it continued in constant darkness for 4 days with a period of approximately 24 h. The settling rhythm was temperature‐compensated and could be reset by 6‐h exposures to light. These observations demonstrate that the settling behavior of P. parkeae is controlled by an endogenous circadian oscillator. Regular low temperature pulses every 12 h removed the inhibition caused by LL and this points to the possible role of temperature changes as stimuli entraining the circadian settling rhythm of P. parkeae.
MACROMOLECULES EXUDED BY SYMBIOTIC DINOFLAGELLATES IN CULTURE: AMINO ACID AND SUGAR COMPOSITION1
Authors: Markell Douglas A. , Trench Robert K. 
Published: August 2006

ABSTRACTFive species of symbiotic dinoflagellates in culture exude water‐soluble glycoconjugates. Recovered glycoconjugates of three of the five species were composed of more carbohydrate than protein. The uronic acid content of three algal species that infect scyphistomae of the jellyfish Cassiopeia were higher than those of the two species that do not infect. Analyses of hydrolysates by high‐performance liquid chromatography indicated that the protein components were rich in aspartic acid (asparagine), glutamic acid (glutamine), serine, glycine, leucine, and threonine and contain proline and lysine. Histidine and methionine, when present, were in low concentration. Other sugars detected were glucose and galactose and their respective amines, ribose, mannose, and fucose. Neither sialic acid nor arabinose was detected. The release of glycoconjugates by symbiotic dinoflagellates appears to be a general phenomenon. Some components of these macromolecules could serve as signals that pass between symbionts and hosts, while other components, assuming host digestion, could be a source of previously undetected essential amino acids.
BLUE LIGHT PHOTOREACTIVATION IN ULTRAVIOLET‐IRRADIATED YOUNG SPOROPHYTES OF ALARIA ESCULENTA AND LAMINARIA SACCHARINA (PHAEOPHYTA)1
Authors: Han Taejun , Kain (Jones) Joanna M. 
Published: August 2006

ABSTRACTExposure of ultraviolet (UV)‐irradiated young sporophytes of Alaria esculenta (L.) Grev. and Laminaria saccharina (L.) Lamour. to visible light resulted in recovery from UV damage that would otherwise cause much higher mortality. For this photoreactivation, blue light was highly effective, whereas negligible reactivation was produced in green or red light. The blue quantum requirements for a 50% response were 1.9 mol·m−2 in A. esculenta and 1.2 mol·m−2 in L. saccharina, which were comparable to those reported for other blue light responses requiring high energy found in brown algae.
DISTRIBUTION AND SYSTEMATICS OF FRESHWATER CERAMIALES (RHODOPHYTA) IN NORTH AMERICA1
Authors: Sheath Robert G. , Vis Morgan L. , Cole Kathleen M. 
Published: August 2006

ABSTRACTTwenty‐five freshwater populations of Ceramiales were collected in North America, 24 of which were from the tropical rainforest region of Central America and the Caribbean. The streams tended to be moderate in mean current velocity (X̄= 23.3 cm·S−1) and maximum width (X̄= 6.3 m) but high in temperature (X̄= 23.1°C), pH (X̄= 7.9), and specific conductance (X̄= 320 μS·cm−1). Three Bostrychia species were restricted to the Caribbean islands: B. moritziana (Sonder ex Kütz.) J. Ag. (syn. B. cornigera Mont. and B. radicans f. moliforme Post), with ecorticate indeterminate axes, monosiphonous ultimate branches, and cladohaptera; B. radicans (Mont.) Mont. (syn. B. leprieurii Mont and B. rivularis Harv.), with ecorticate and polysiphonous axes throughout and cladophaptera; and B. tenella (Lamour.) J. Ag., with corticate indeterminate axes, monosiphonous ultimate branches, and peripherohaptera. Ballia prieurii Kütz. was found in Belize and Costa Rica and was characterized by rebranched determinate laterals, opposite branching, and long apical cells (X̄= 61 μm) and axial cells (X̄= 43 μm). Caloglossa leprieurii (Mont.) J. Ag. was localized in Puerto Rico while. C. ogasawaerensis Okam. was collected only in Costa Rica. The two species were separated by site of branching (midrib vs. margin) and blade width (X̄= 384 vs. 861 μm). Polysiphonia subtilissima Mont. from Florida and Jamaica had four pericentral cells, no cortication, rhizoids arising from pericentral cells, and branches initiated at trichoblast scars.
PHYSIOLOGICAL RESPONSES TO TEMPERATURE AND IRRADIANCE IN SPIROGYRA (ZYGNEMATALES, CHAROPHYCEAE)1
Authors: Graham James M. , Lembi Carole A. , Adrian Holly L. , Spencer David F. 
Published: August 2006

ABSTRACTSpirogyra Link (1820) is an anabranched filamentous green alga that forms free‐floating mats in shallow waters. It occurs widely in static waters such as ponds and ditches, sheltered littoral areas of lakes, and stow‐flowing streams. Field observations of its seasonal distribution suggest that the 70‐μm‐wide filament form of Spirogyra should have a cool temperature and high irradiance optimum for net photosynthesis. Measurements of net photosynthesis and respiration were marie at 58 combinations of tight and temperature in a controlled environment facility. Optimum conditions were 25°C and 1500 μmol photons m−2 s−1, at which net photosynthesis averaged 75.7 mg O2 gdm−1 h−1. Net photosynthesis was positive at temperatures from 5° to 35°C at most irradiances except at combinations of extremely low irradiances and high temperatures (7 and 23 μmol photons m−2 s−1 at 30°C and 7, 23, and 35 μmol photons m−2 s−1 at 35°C). Respiration rates increased with both temperature and prior irradiance. Light‐enhanced respiration rates were significantly greater than dark respiration rates following irradiances of 750 μmol photons m−2 s−1 or greater. Polynomials were fitted to the data to generate response surfaces; such response surfaces can be used to represent net photosynthesis and respiration in ecological models. The data indicate that the alga can tolerate the cool water and high irradiances characteristic of early spring but cannot maintain positive net photosynthesis under conditions of high temperature and low light (e.g. when exposed to self‐shading).
PIGMENTS OF BATHYCOCCUS PRASINOS (PRASINOPHYCEAE): METHODOLOGICAL AND CHEMOSYSTEMATIC IMPLICATIONS1,2
Authors: Egeland Einar Skarstad , Johnsen Geir , Eikrem Wenche , Throndsen Jahn , Liaaen‐Jensen Synnøve 
Published: August 2006

ABSTRACTBathycoccus prasinos Eikrem et Throndsen exhibited a complex carotenoid distribution pattern including the carotenes β,β‐carotene (0.8% of total carotenoids) and β, ° Carotene (0.4%) and several xanthophylls. These were prasinoxanthin (49% of total carotenoids), micromonal (16%), neoxanthin (14%), uriolide (7%), violaxanthin (0.8%), 31‐dehydrouriolide (0.8%), dihydrolutein (0.1%), two partly characterized esterified carotenols (together 10%), and five minor unidentified carotenols (together 2%). The identifications were based on high‐performance liquid chromatography (HPLC), thin‐layer chromatography (TLC), visible spectroscopy (VIS), and mass spectra (MS) and in part on 1H nuclear magnetic resonance (NMR), circular dichroism (CD), and chemical derivatization. The carotenoid composition of B. prasinos was related to that of other prasinoxanthin / uriolide / micromonal‐producing prasinophytes (Mantoniella squamata, Micromonas pusilla, and Pseudoscourfieldia marina). The relative distribution of chlorophylls (w/w) were chlorophyll a (chl a; 63%), chl b (31%), and an unknown chl c‐like chlorophyll (7%) with spectral characteristics similar to magnesium 2,4‐divinylphaeoporphyrin a, monomethyl ester, compatible with other prasinophytes. The chemosystematic data and ultrastructural characteristics for the order Mamiellales are discussed. We conclude that HPLC studies alone are insufficient for the identification and characterization of the carotenoids, including the minor carotenoids essential for biosynthetic/chemosystematic considerations.
ISOLATION, PURIFICATION, AND CHARACTERIZATION OF DMSP LYASE (DIMETHYLPROPIOTHETIN DETHIOMETHYLASE (4.4.1.3)) FROM THE RED ALGA POLYSIPHONIA PANICULATA1
Authors: Nishiguchi Michele K. , Goff Lynda J. 
Published: August 2006

ABSTRACTPolysiphonia paniculata Montagne is an intertidal red alga known to produce large amounts of the compound dimethylsulfoniopropionate (DMSP). Conversion of this substrate into dimethylsulfide is accomplished in P, paniculata by an enzyme called DMSP lyase (dimethylpropiothetin dethiomethyla.se (4.4.1.3)). DMSP lyase has been purified and characterized from P. paniculata. Enzymie activity is found in two different proteins: the larger with a molecular weight of 9.26 ± 104 daltons and the smaller with a molecular weight of 3.65 ± 104 daltons. Specific activity of the enzyme is 526 μmols min−1mg−1 for the smaller protein a nd 263 μmols min −1 mg−1 for the la rger protein. The Michaelis‐Menten constant (Km) is 72.8 μM ± 17.15 and the vmax is 1.62 μmols min−1± 0.928 for the 92.6‐kDa protein. The p1 of the larger protein is 5.8 and 5.9 for the smaller protein. Interaction with cysteine protease inhibitors L‐trans‐epoxysuccinyl‐leucylamido (4‐guanidino)‐butane, dithiobis‐(2‐nitrobenzoate), or N‐ethylmaleimide inactivated enzyme activity. The presence of either magnesium or calcium with DMSP lyase enhanced activity al concentrations between 20 and 40 μM but had little effect above these levels. Addition of the divalent chelators ethylenebis(oxyethylenenitrilo) tetraacetic acid and ethylenediaminetetraacetate decreased activity of the enzyme, but activity was restored when either chelator was removed and magnesium or calcium was added to the enzyme.
THE FUCUS (PHAEOPHYCEAE) SPERM RECEPTOR FOR EGGS. I. DEVELOPMENT AND CHARACTERISTICS OF A BINDING ASSAY1
Authors: Wright Philip J. , Green Jonathan R. , Callow James A. 
Published: August 2006

ABSTRACT To explore the molecular basis of egg‐sperm recognition in the brown alga, Fucus serratus L., we developed an in vitro binding assay involving egg plasma membrane vesicles (PMVs) and proteins contained in a KCl extract of sperm. Binding between the two components was measured using biotinylated PMVs followed by the addition of streptavidin conjugated to alkaline phosphatase and the appropriate substrate. Biotinylation did not affect the ability of egg PMVs to inhibit fertilization in a species‐preferential manner. Binding of labeled egg PMVs to the sperm KCl extract was saturable and competable with unlabeled PMVs but was not species‐specific. Protease treatment of the KCl extract abolished binding, whereas periodate had no effect, suggesting that sperm protein rather than carbohydrate was involved. Preincubation of the sperm extract with sulfated polysaccharides (e.g. fucoidan and ascophyllan) inhibited binding of egg plasma membranes. Sulfation seems to be important for this effect since desulfated fucoidan was far less effective at blocking binding. Polysaccharides which inhibited binding also inhibited fertilization. Overall, the results indicate that at least some aspects of binding between Fucus sperm and eggs are mediated by a protein(s) derived from sperm which recognizes sulfated glycoconjugates on the egg plasma membrane.
SEXUAL DIFFERENTIATION OF GRIFFITHSIA (CERAMIALES, RHODOPHYTA): NUCLEAR PLOIDY LEVEL OF MIXED‐PHASE PLANTS IN G. JAPONICA1
Authors: Lee Yoo Kyung , Choi Han‐Gu , Hong Choo Bong , Kyu Lee In 
Published: August 2006

ABSTRACT Mixed‐phase plants of Griffithsia japonica Okamura spontaneously occurred in a laboratory culture. Four female plants produced tetrasporangia and spermatangia in addition to their normal female reproductive structures (bisexual/mixed‐phase plants), and four male plants produced tetrasporangia as well as spermatangia (male/mixed‐phase plants). To determine the nuclear ploidy level of these mixed‐phase plants, relative nuclear sizes of male, female, tetrasporangial, and mixed‐phase plants were measured using a microscopic image analysis system. Haploid gametophytes could be distinguished from diploid tetrasporophytes by relative nuclear sizes, with the later having nuclei twice the size of the former. Relative nuclear sizes of the mixed‐phase plants were similar to those of the haploid plants. Thus, the mixed‐phase plants were determined to be haploid. Haploid mixed‐phase plants of G. japonica have a potential to produce male, female and tetrasporangial reproductive structures. Sex determination models are discussed to explain “haploid” mixed‐phase phenomena in red algae.
Development of an immunological technique for identifying multiple predator–prey interactions in a complex arthropod assemblage
Authors: Hagler J.R. 
Published: August 2006

AbstractA simplified but highly effective approach for the post‐mortem evaluation of predation on several targeted members of an arthropod assemblage that does not require the development of pest‐specific enzyme‐linked immunosorbent assay (ELISA) (e.g. pest‐specific monoclonal antibodies) or PCR assays (DNA primers) is described. Laboratory feeding studies were conducted to determine if predation events could be detected from predators that consumed prey marked with foreign protein. I determined that large and small rabbit immunoglobulin G (IgG)‐marked prey can be detected by a rabbit‐IgG‐specific ELISA in the guts of chewing and piercing–sucking type predators. I then conducted multifaceted inclusion and exclusion field cage studies to qualify the degree of interguild and intraguild predation occurring among a complex arthropod assemblage during four separate light phase treatments. The field cages contained an arthropod assemblage consisting of 11 or 12 species of predaceous arthropods and three pest species. The three pests introduced into the cages included third instar Trichoplusia ni marked with rabbit IgG, third instar Lygus hesperus marked with chicken IgG and Pectinophora gossypiella sentinel egg masses. The inclusion cages allowed foraging fire ants, Solenopis xyloni, to freely enter the cages while the exclusion cages contained barriers that prevented ant entry. The results obtained using the conventional inclusion/exclusion field cage methodology revealed that there was substantial interguild and intraguild predation occurring on the majority of the arthropods in the assemblage, particularly in those cages that included ants. I then precisely identified which predators in the assemblage were feeding on the three targeted pests by conducting three post‐mortem gut content analyses on each individual predator (1503 individuals) in the assemblage. Specifically, P. gossypiella egg predation events were detected using an established P. gossypiella‐egg‐specific ELISA, and third instar T. ni and L. hesperus predation events were detected using rabbit‐IgG‐specific and chicken‐IgG‐specific ELISAs, respectively. Generally, the gut ELISAs revealed that Collops vittatus, Spanagonicus albofasciatus and Geocoris punctipes readily preyed on P. gossypiella eggs; Nabis alternatus, Zelus renardii and spiders (primarily Misumenops celer) readily preyed on marked L. hesperus nymphs, and spiders, S. albofasciatus and N. alternatus readily preyed on T. ni larvae. Furthermore, the cage methods and the post‐mortem predator gut ELISAs revealed very few distinctive patterns of predation with regard to the light cycle the assemblage was exposed to.
Nickel levels in arthropods associated with Ni hyperaccumulator plants from an ultramafic site in New Caledonia
Authors: BOYD ROBERT S. , WALL MICHAEL A. , JAFFRÉ TANGUY 
Published: August 2006

AbstractArthropods (mainly insects) were collected from a forest site that contained at least six species of Ni hyperaccumulators. Whole body Ni analysis was performed for 12 arthropod taxa, two of which were studied at different life cycle stages. We found two Nitolerant insects. The pentatomid heteropteran Utana viridipuncta, feeding on fruits of the Ni hyperaccumulator Hybanthus austrocaledonicus, contained a mean of 2 600 μNi/g in nymphs and 750 μNi/g in adults. The tephritid fly Bactrocera psidii, feeding on pulp of Sebertia acuminata fruits that contained 6 900 μNi/g, contained 420 μNi/g as larvae that had evacuated their guts and significantly less (65 μNi/g) as adults. European honeybees (Apis mellifera) visiting flowers of the Ni hyperaccumulator H. austrocaledonicus contained significantly more Ni (8‐fold more) than those collected from flowers of Myodocarpus fraxinifolius, a non‐hyperaccumulator. Our results show that some insects feed on Ni hyperaccumulator plants and that their feeding mobilizes Ni into local food webs.
Impact of transgenic Bacillus thuringiensis cotton on a non‐target pest Tetranychus spp. in northern China
Authors: MA XIAO‐MU , LIU XIAO‐XIA , ZHANG QING‐WEN , LI JI‐JUN , REN AI‐MIN 
Published: August 2006

AbstractField studies were carried out to evaluate the effect of two transgenic cotton varieties (SGK321 carrying Cry1A+CpTI and DP99B carrying Cry1Ac) and the conventional variety (shiyuan321‐parental line of SGK321) on spider mites, Tetranychus spp. from 2002 to 2004. In 2002, this experiment included three treatments: Bt cotton field (SGK321) treated with acaricides against spider mites, untreated non‐Bt cotton field (Shiyuan321), and untreated Bt cotton field (SGK321). In 2003–2004, there are four types of treatments after a new transgenic Bt cotton variety, DP99B (non‐chemical control), was added into the experiments. The results showed that there were no significant difference in densities of spider mites among Bt without acaricides and non‐Bt without acaricides cotton fields, nor was there a significant difference in damage of spider mites to cotton among these treatments (P > 0.1). However, there are significant differences (P < 0.05) in densities of spider mites and damage caused by spider mites between cotton fields with and without acaricides. Acaricide significantly reduced the densities of spider mites in Bt cotton (P < 0.05). These results suggest that Bt cotton has no effect on spider mites populations. However, spider mites have the potential for severe damage in Bt cotton fields. Acaricides are essential tools in controlling cotton spider mites in northern China.
Effects of seed type and bruchid genotype on the performance and oviposition behavior of Zabrotes subfasciatus (Coleoptera: Bruchidae)
Authors: CAMPAN ERICK D. M. , BENREY BETTY 
Published: August 2006

AbstractThe effect of different bean varieties on the performance of the bruchid beetle Zabrotes subfasciatus Boheman (Coleoptera: Bruchidae), was determined by using wild and cultivated seeds of the genus Phaseolus. Results showed that the quality of the host plant affected the performance and the oviposition behavior of female beetles. Overall, bruchid performance was higher on cultivated seeds than on wild seeds. It was also found that the oviposition behavior and the performance of their offspring differed between females that originated from wild versus cultivated seeds. We also demonstrated the importance of a genetic component in bruchid performance: longevity, fecundity, larval development, adult size, and the sex ratio of the progeny varied according to their maternal lineage (‘familyrsquo;). For example, on the same host type, some females laid twice as many eggs as females from other ‘familiesrsquo;, and the sex ratio among the offspring correlated with that of their mother. Thus, the performance and behavior of Z. subfasciatus are not only affected by environmen tal factors such as the quality of the seeds on which they develop, but also have a genetic basis which can counterbalance a less suitable quality of the host plant. For a crop pest such as Z. subfasciatus, its ability to survive and adapt on host plants of differing quality may be an important attribute to consider for pest management.