Breeding records of hooded vultures Necrosyrtes monachus (Timminek, 1823) at Kpokap, Zango Kataf Local Government Area, Kaduna State, Nigeria

Nesting of vultures was studied alongside with their population and distribution. Vulture’s nest is usually occupied by male and female for successful incubation of egg(s) and rearing of the chick(s). Continuation and preservation of an organism is achieved through conducive breeding habitat; vultures inclusive. Two nests were found at Kpokap all on Giant cola tree (Cola gigantea). The nests were placed each at the fork of the tree trunk. Nest 1 was located at about 9.5m above the ground while nest 2 was located at about 8.5m above the ground. The monogamous vultures fly out from their nests but hoover around whenever they felt threatened. This study is aimed at preserving the breeding pairs of vultures found at the study areas as fast as possible

Preference and performance of Phyllocnistis citrella Stainton (Lepidoptera:Gracillariidae) on three citrus hosts: Laboratory and field assessment

The relationship between preference and performance is crucial to the ecology and evolution of plant-insect interactions. Oviposition preference and offspring performance were evaluated for a citrus pest, the leafminer Phyllocnistis citrella (Lepidoptera: Gracillariidae), on three of its host plants: lemon (Citrus limon L. Burm.), orange (Citrus sinensis L. Osbeck), and grapefruit (Citrus paradisi Macfadyen) in Tucumán province (northwest Argentina). Choice and no-choice tests were performed in open and enclosed environments, and performance parameters (development time, survival, pupal size, and sex ratio) were estimated from laboratory rearing and 3-yr field sampling data. Parasitism rates were studied in laboratory choice test and field assessments. Preference trends were inconsistent, with lemon receiving more eggs in some tests, whereas no preference was observed in others. Patterns of host use in the field did not show significant differences among species. Leafminer performance, including parasitism and predation rates, was generally homogeneous among host plants. From these results, lemon, orange, and grapefruit seem to represent intrinsically similar resources for P. citrella populations in northwest Argentina, a trend that was accompanied by a lack of consistent oviposition preferences in foraging females. Ecological conditions might be more important than physiological adaptation in shaping a probably labile host ranking in this pest species.La relación entre preferencia y rendimiento es crucial para la ecología y evolución de las interacciones insecto-planta. Se evaluó la preferencia de puesta y el rendimiento de la descendencia para una plaga de cítricos, el minador de la hoja Phyllocnistis citrella (Lepidoptera: Gracillariidae), sobre tres de sus plantas hospederas: limonero (Citrus limon [Linn.] Burm.), naranjo (Citrus sinensis [Linn.] Osbeck) y pomelo (Citrus paradisi Macfadyen) en la provincia de Tucumán (Noroeste de Argentina). Se realizaron pruebas con y sin elección en ambientes abiertos y cerrados, y se estimaron parámetros de rendimiento (tiempo de desarrollo, supervivencia, tamaño pupal y proporción de sexos) a partir de individuos criados en laboratorio y datos de tres años de muestreos de campo. Las tasas de parasitismo se estudiaron en pruebas de laboratorio con elección y evaluaciones en campo. Las tendencias de preferencia fueron inconsistentes, con limonero recibiendo más huevos en algunas pruebas, mientras que no se observó preferencia en otras. Los patrones de uso de hospedero en campo no mostraron diferencias significativas entre especies. El rendimiento del minador, incluyendo las tasas de parasitismo y depredación, fue generalmente homogéneo entre plantas hospederas. Con estos resultados, las plantas de limonero, naranjo y pomelo representarían intrínsecamente recursos similares para las poblaciones del minador de los cítricos en el NO de Argentina, tendencia que fue acompañada por la ausencia de preferencias consistentes en la puesta de huevos por parte de las hembras. Las condiciones ecológicas podrían ser más importantes que la adaptación fisiológica al moldear un rango de hospederos probablemente voluble en esta especie plaga.Fil: Goane, Lucía. Gobierno de Tucumán. Ministerio de Desarrollo Productivo. Estación Experimental Agroindustrial Obispo Colombres; ArgentinaFil: Valladares, Graciela Rosa. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; ArgentinaFil: Willink, Eduardo. Gobierno de Tucumán. Ministerio de Desarrollo Productivo. Estación Experimental Agroindustrial Obispo Colombres; Argentin

WOW Factors in Secondary Science

Booklet of exciting practicals to do with Secondary school pupils. Each activity tested and written up by a Secondary PGCE or GTP student; some updated by other students in the following year. Templates all follow the same pattern and include risk assessments, materials needed, links to the curriculum et

Cladoceran birth and death rates estimates

I. Birth and death rates of natural cladoceran populations cannot be measured directly. Estimates of these population parameters must be calculated using methods that make assumptions about the form of population growth. These methods generally assume that the population has a stable age distribution. 2. To assess the effect of variable age distributions, we tested six egg ratio methods for estimating birth and death rates with data from thirty-seven laboratory populations of Daphnia pulicaria. The populations were grown under constant conditions, but the initial age distributions and egg ratios of the populations varied. Actual death rates were virtually zero, so the difference between the estimated and actual death rates measured the error in both birth and death rate estimates. 3. The results demonstrate that unstable population structures may produce large errors in the birth and death rates estimated by any of these methods. Among the methods tested, Taylor and Slatkin's formula and Paloheimo's formula were most reliable for the experimental data. 4. Further analyses of three of the methods were made using computer simulations of growth of age-structured populations with initially unstable age distributions. These analyses show that the time interval between sampling strongly influences the reliability of birth and death rate estimates. At a sampling interval of 2.5 days (equal to the duration of the egg stage), Paloheimo's formula was most accurate. At longer intervals (7.5–10 days), Taylor and Slatkin's formula which includes information on population structure was most accurate

Interactions between the oomycete Pythium arrhenomanes and the rice root-knot nematode Meloidogyne graminicola in aerobic Asian rice varieties

Background: Aerobic rice fields are frequently infested by pathogenic oomycetes (Pythium spp.) and the rice root-knot nematode Meloidogyne graminicola. Here, the interaction between Pythium arrhenomanes and Meloidogyne graminicola was studied in rice roots of two aerobic rice varieties. In different experimental set-ups and infection regimes, plant growth, rice yield, Pythium colonization, as well as establishment, development and reproduction of M. graminicola were studied. Results: In this study, it is shown that the presence of P. arrhenomanes delays the establishment, development and reproduction of M. graminicola compared to single nematode infected plants. The delay in establishment and development of M. graminicola becomes stronger with higher P. arrhenomanes infection pressure. Conclusions: Our data indicate that P. arrhenomanes antagonizes M. graminicola in the rice root and that the plant benefits from this antagonism as shown by the yield data, especially when either of the pathogens is present in high levels

Implications of hybridisation and cytotypic differentiation in speciation assessed by AFLP and plastid haplotypes : a case study of Potentilla alpicola La Soie

Background: Hybridisation is presumed to be an important mechanism in plant speciation and a creative evolutionary force often accompanied by polyploidisation and in some cases by apomixis. The Potentilla collina group constitutes a particularly suitable model system to study these phenomena as it is morphologically extensively variable, exclusively polyploid and expresses apomixis. In the present study, the alpine taxon Potentilla alpicola has been chosen in order to study its presumed hybrid origin, identify underlying evolutionary processes and infer the discreteness or taxonomic value of hybrid forms. Results: Combined analysis of AFLP, cpDNA sequences and ploidy level variation revealed a hybrid origin of the P. alpicola populations from South Tyrol (Italy) resulting from crosses between P. pusilla and two cytotypes of P. argentea. Hybrids were locally sympatric with at least one of the parental forms. Three lineages of different evolutionary origin comprising two ploidy levels were identified within P. alpicola. The lineages differed in parentage and the complexity of the evolutionary process. A geographically wide-spread lineage thus contrasted with locally distributed lineages of different origins. Populations of P. collina studied in addition, have been regarded rather as recent derivatives of the hexaploid P. argentea. The observation of clones within both P. alpicola and P. collina suggested a possible apomictic mode of reproduction. Conclusions: Different hybridisation scenarios taking place on geographically small scales resulted in viable progeny presumably stabilised by apomixis. The case study of P. alpicola supports that these processes played a significant role in the creation of polymorphism in the genus Potentilla. However, multiple origin of hybrids and backcrossing are considered to produce a variety of evolutionary spontaneous forms existing aside of reproductively stabilised, established lineages

Historic U.A.W. Leader Speaks out for Retirees and Workers

This article is part of the collection of writings of Marshall (Mike) Westfall, retired autoworker from General Motors in Flint, Michigan (1964-1994) and activist critic of the auto industry restructuring that led to devastating job losses. It originally appeared online in The Westfall Papers.[http://michaelwestfall.tripod.com/id110.html, accessed 12/14/2011

Spartan Daily, November 5, 1941

Volume 30, Issue 30https://scholarworks.sjsu.edu/spartandaily/3350/thumbnail.jp

Iconic product advantage for improving marketing performance of Indonesian small and medium enterprises

Purpose: To examine the role of iconic product advantage to improve marketing performance. Design/Methodology/Approach: This study uses primary data obtained from interviews based on a list of questions to 103 respondents of Salted Egg SMEs in Brebes Regency, Central Java Province, Indonesia. Findings: All hypotheses are accepted, market orientation influences iconic product advantage, product innovation influences iconic product advantage, dynamic capability influences iconic product advantage, iconic product advantage influences marketing performance. Practical Implications: There is no research that examines the market orientation of marketing performance that is bridged by the iconic product advantage. This research proves that the iconic product advantage bridges the market orientation with the marketing performance of Brebes Salted Egg SMEs that is supported by product innovation and dynamic capability. Originality/Value: Iconic product advantage is novelty in this study. Iconic product advantage is the superiority of the company by making products that become icons or symbols that serve as a reminder for consumers with the symbols contained in the product.peer-reviewe