Orobanche icterica (Orobanchaceae) revisited

Orobanche icterica Pau, frequently regarded as a synonym for O. elatior Sutton, is lectotypified on Pau's original material from the herbarium of the Real Jardín Botánico in Madrid (MA 115079!). Its morphology is described with special emphasis on those characters which distinguish it from O. elatior. O. icterica is mainly found in the east of the Iberian Peninsula and sporadically in the south and north-west. It is considered to be close to O. elatior but deserving recognition at specific level.  © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society , 2005, 148 , 117–124.     

A trans‐national monarch butterfly population model and implications for regional conservation priorities

1. The monarch has undergone considerable population declines over the past decade, and the governments of Mexico, Canada, and the United States have agreed to work together to conserve the species. 2. Given limited resources, understanding where to focus conservation action is key for widespread species like monarchs. To support planning for continental‐scale monarch habitat restoration, we address the question of where restoration efforts are likely to have the largest impacts on monarch butterfly (Danaus plexippus Linn.) population growth rates. 3. We present a spatially explicit demographic model simulating the multi‐generational annual cycle of the eastern monarch population, and use the model to examine management scenarios, some of which focus on particular regions of North America. 4. Improving the monarch habitat in the north central or southern parts of the monarch range yields a slightly greater increase in the population growth rate than restoration in other regions. However, combining restoration efforts across multiple regions yields population growth rates above 1 with smaller simulated improvements in habitat per region than single‐region strategies. 5. S ynthesis and applications: These findings suggest that conservation investment in projects across the full monarch range will be more effective than focusing on one or a few regions, and will require international cooperation across many land use categories.     

DEVELOPMENT OF A LEXICON FOR BEEF FLAVOR IN INTACT MUSCLE

ABSTRACT

A lexicon describing the flavor characteristics of beef across different cuts, grades, and cooking temperatures and methods was developed. Four major cuts of the United States Department of Agriculture (USDA) quality grade beef were cooked to five endpoint temperatures using braising, broiling (oven broiling and electric charbroiling), roasting and grilling (indoor and outdoor grilling). Six highly trained panelists identified and defined a total of 38 aroma and flavor characteristics in 176 beef samples. Beef identity, brown/roasted, bloody/serumy, metallic, fat‐like, overall sweet, sour aromatics and five tastes were present in practically all samples. Other attributes were present only in certain samples, depending on either the sample group or the cooking method/endpoint temperature combination used. This lexicon potentially offers the beef industry a standard tool to identify and quantify flavor attributes as impacted by temperature, cooking method, aging process, storage time, diet regime, packaging, USDA quality grades, etc.

PRACTICAL APPLICATIONS

Until now, the beef industry's main focus has been to assess beef tenderness and juiciness, with an emphasis on ways to improve beef texture. Meat companies and academic institutions have been using the 1995 American Meat Science Association guidelines to assess the flavor of beef, which are not comprehensive. Recent work has focused on flavor, and the industry needs a standardized flavor lexicon that can be used for many projects. It is important for the industry to be able to systematically identify and quantify flavor attributes that drive consumer acceptance.     

2,3-BUTANEDIONE INACTIVATES THE [H]NITRENDIPINE BINDING SITES, WHEREAS DIETHYLPYROCARBONATE DOES NOT

The modification of [³H]nitrendipine binding sites in rabbit brain membranes with 2,3-butanedione and diethylpyrocarbonate was investigated. 2,3-Butanedione, an arginine-specific reagent, causes a dose- and time-dependent decrease in the number of [³H]nitrendipine binding sites without altering its dissociation constant. Scatchard analysis of the binding data shows that 50 mM 2,3-butanedione decreases the binding capacity of [³H]nitrendipine from a control value of 71 ± 6 fmol/mg of protein to 40 ± 3 fmol/mg of protein. Complete and selective protection against inactivation is provided by nifedipine. No decrease of [³H]nitrendipine binding occurs when membranes are pretreated with selective histidine reagent diethylpyrocarbonate. The results indicate that arginine but not histidine residue in

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-type calcium channel domain is critical for [³H]nitrendipine binding. Copyright © 1996 Elsevier Science Ltd     

Culture senescence and abscisic acid induce saporin production in cultured roots of Saponaria officinalis

The presence and variation of activity of the type 1 ribosome-inactivating protein saporin has been evaluated in cultured roots of the soapwort Saponaria officinalis . Results from western analysis and in vitro protein synthesis inhibition indicate that saporin production is increased in senescing cultures, reaching a maximum value during the late stationary phase. Accordingly, cultures treated with the senescence-related hormone abscisic acid show a significant increase in saporin activity, independently from the culture growth phase. Stress conditions, such as the presence of hydrogen peroxide in the culture medium, had no effect on the modulation of enzymatic activity. The putative regulation of saporin production by abscisic acid and its possible role in accomplishing the ageing programme is discussed.     

The Shifting Middle Ground: Amazonian Indians and Eco-Politics

Over the past decade in Brazil, the convergence between international environmentalism and indigenous cultural survival concerns led to an unprecedented internationalization of local A native struggles. The Indian-environmentalist alliance has benefited both parties, but recent events suggest that it may be unstable and may pose political risks for native people. The limitations of transnational symbolic politics as a vehicle for indigenous activism reflect tensions and contradictions in outsiders' symbolic constructions of Indian identity.     

Plasticity of the phonotactic selectiveness of four species of chirping crickets (Gryllidae): Implications for call recognition

Earlier studies of phonotaxis by female crickets describe this selective behavioural response as being important in the females' choices of conspecific males, leading to reproduction. In the present study, moderate (30+) to very large data sets of phonotactic behaviour by female Acheta domesticus L., Gryllus bimaculatus DeGeer, Gryllus pennsylvanicus Burmeister and Gryllus veletis Alexander demonstrate substantially greater plasticity in the behavioural choices, as made by females of each species, for the syllable periods (SP) of model calling songs (CS) than has been previously described. Phonotactic choices by each species range from the very selective (i.e. responding to only one or two SPs) to very unselective (i.e. responding to all SPs presented). Some females that do not respond to all SPs prefer a range that includes either the longest or shortest SP tested, which fall outside the range of SPs produced by conspecific males. Old female A. domesticus and G. pennsylvanicus are more likely to be unselective for SPs than are young females. Each species includes females that do not respond to a particular SP when responding to CSs with longer and shorter SPs. The results suggest that the plasticity of phonotactic behaviour collectively exhibited by the females of each species does not ensure that choices of a male's CS effectively focus the female's phonotactic responses on CSs that represent the conspecific male. The phonotactic behaviour collectively exhibited by females of each species does not readily fit any of the models for selective processing by central auditory neurones that have been proposed to underlie phonotactic choice.     

Ecophysiological effects of light quality and nitrate on seed germination in species from Western Australia

Germination occurs usually in response to multiple environmental cues. Seeds with the ecophysiological ability to simultaneously sense the previous presence of fire and appropriate levels of temperature, light and soil nitrate could restrict germination to postfire, winter and competition-free microhabitats, where the potential for seedling survival is enhanced. Germination responses of 16 species with a range of life forms, fire responses and seed weights were determined under controlled conditions of 15°C temperature, a 12 h light cycle, exposure to 1 g L^?1 nitrate solution, and six conditions of light quality (white, blue, yellow, red, far-red light and darkness). Germination in Oenothera stricta, a weedy naturalized ephemeral, and two small-seeded indigenous Asteraceae species of mulga woodlands, Leucochrysum fitzgibbonii and Craspedia sp., were enhanced by white, yellow or red light compared with germination achieved in the dark, or under far-red or blue light. In red light, KNO₃ further enhanced germination of these positively photoblastic species. The germination response of Trachyandra divaricata, a naturalized herb of sandy, seaside locations, and several native jarrah forest legumes (four Acacia species, Bossiaea aquifolium, Gompholobium marginatum and Sphaerolobium vimineum) proved to be negatively photoblastic. Of these seven negatively photoblastic herb and shrub species, exposure to KNO₃ overcame the inhibition of light only in the resprouter species, Acacia lateriticola. In the serotinous, negatively photoblastic tree species, Corymbia calophylla and Eucalyptus marginata, KNO₃ seemed to be required before the negative response to light exposure was recorded. A dose–curve experiment on two positively photoblastic and three negatively photoblastic species indicated that although KNO₃ exposure affected germination in all species, different concentrations of KNO₃ (0, 0.5, 1, 2, and 5 g L^?1) produced different levels of response. Detailed studies with additions of KNO₃ (1 g L^?1) and the growth hormone, gibberellic acid (GA₃; 50 mg L^?1), showed that increased germination percentages of the positively photoblastic species, Oenothera stricta, occurred in the light, but blocking endogenous gibberellic synthesis with paclobutrazol, or adding exogenous GA₃ or KNO₃ had no effect on the light-induced germination levels. In the negatively photoblastic species Trachyandra divaricata, additions of KNO₃ and GA₃ had no influence on the germination inhibition induced by exposure to light nor did blocking endogenous GA synthesis. The 16 species growing naturally in Western Australia, Australia show a range of germination responses to environmental conditions, but depending on their natural habitat, the ecophysiology of each species appears to be optimized for subsequent seedling survival.