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Effects of Cold and Heat Stress on Egg Quality Traits of a Newly Developed Native Hybrid Layer Full text
2015
İsmail Durmuş | Serdar Kamanlı
Effects of Cold and Heat Stress on Egg Quality Traits of a Newly Developed Native Hybrid Layer Full text
2015
İsmail Durmuş | Serdar Kamanlı
ATAK-S is a newly developed native hybrid layer. Although the laying performance of this hybrid has been studied and determined, the performance response of the hybrid to different environmental temperature conditions is not known. This study was therefore undertaken to determine the effect of cold and heat stress on egg quality traits. Hens were divided into three different groups; control (20°C), low (12°C) and high (32°C). A total of 360 hens, with 120 in each of the groups, were used in the study. Hens were held in three tier battery cages in an environmentally controlled poultry house. The study lasted for 3 weeks. No differences were found among different groups in terms of shape index, albumen height and Haugh unit of the egg quality traits. It was found that the differences among the heat groups in terms of egg shell breaking strength, egg weight, shell thickness and yolk colour were significant and the value of these traits decreased under the heat stress conditions, whereas they were not affected from the cold stress.
Show more [+] Less [-]Evaluation of diversity and distribution patterns of Passiflora subgenus Astrophea (Passifloraceae) in Colombia. A challenge for taxonomic, floristic and conservation research of the species | Evaluación de la diversidad y patrones de distribución de Passiflora subgénero Astrophea (Passifloraceae) en Colombia. Un reto para la investigación taxonómica, florística y de conservación de las especies Full text
2016
Aguirre-Morales, Adriana Carolina | Bonilla Morales, Miguel Macgayver | Caetano, Creucí Maria
Passiflora with approx. 575 species is the most diverse genus in Passifloraceae, with Colombia and Ecuador holding the largest number of taxa. It is divided into five subgenera, one of them being Astrophea, a group of arborescent and woody species. The aim of this research, was to assess the diversity and conservation status of the species in the subgenus Astrophea native to Colombia, and investigate their current and potential distribution. Subsequently, national and international herbarium collections and scientific literature were reviewed. This research was further supplemented by recent field collections. The results were analyzed with Excel © and maps obtained by Diva-GIS © to which the IUCN criteria were applied for each species. 24 species were identified, distributed within 28 departments, by assessing 375 records. The potential distribution ranges of the species, suggests niches associated to the Amazonía and Orinoquía, bioregions with large gaps in collection, provided they are in the species preferred altitudinal ranges (0-500 m). The most diverse parts of the country are the center west and northeast, with more than 7 taxa per area. 46% of species have some degree of threat and 37.5% are endemic. Despite this, 80% of species occur outside protected areas, which further complicate its conservation status according to the IUCN criteria. Eleven species are newly reported for the 14 departments. Collection efforts should be focused on areas with optimal bioclimatic conditions for the growth of species as regions for potential distribution. | Passiflora con ca. 575 especies es el género más rico de Passifloraceae cuyo centro de diversidad está en Colombia y Ecuador. Éste se divide en cinco subgéneros, entre estos Astrophea agrupa las especies arborescentes y leñosas. El propósito de la investigación fue conocer la diversidad y estado de conservación de especies del subgénero Astrophea para Colombia, sumando aspectos de distribución actual y potencial. Por lo anterior, se revisaron colecciones de herbarios nacionales e internacionales y literatura científica, complementando con colectas de campo. Los resultados fueron analizados con Excel© y los mapas obtenidos mediante Diva-GIS©, además los criterios de la IUCN se aplicaron para cada especie. Se registraron 375 observaciones, agrupadas en 24 especies y distribuidas en 28 departamentos, a lo largo de los valles interandinos del río Cauca y Magdalena. La distribución potencial, sugiere nichos asociados a las regiones de Amazonía y Orinoquía; bioregiones con amplios vacíos de colecta ubicadas dentro de las preferencias de distribución por rango altitudinal de las especies (0-500 m.s.n.m.). Las áreas con mayor riqueza son el centro occidente y nororiente del país con más de siete especies por zona. Pese a esto, el 80% de las especies están por fuera de áreas protegidas, lo que se agrava bajo los criterios de la IUCN, pues el 46% presentan algún grado de amenaza, además del alto porcentaje de endemismo (37,5%). Once especies son incluidas como nuevos reportes para 14 departamentos. Esfuerzos de colecta deben orientarse en las regiones de distribución potencial que poseen condiciones bioclimáticas óptimas para el desarrollo de las especies. | Passiflora con ca. 575 especies es el género más rico de Passifloraceae cuyo centro de diversidad está en Colombia y Ecuador. Éste se divide en cinco subgéneros, entre estos Astrophea agrupa las especies arborescentes y leñosas. El propósito de la investigación fue conocer la diversidad y estado de conservación de especies del subgénero Astrophea para Colombia, sumando aspectos de distribución actual y potencial. Por lo anterior, se revisaron colecciones de herbarios nacionales e internacionales y literatura científica, complementando con colectas de campo. Los resultados fueron analizados con Excel© y los mapas obtenidos mediante Diva-GIS©, además los criterios de la IUCN se aplicaron para cada especie. Se registraron 375 observaciones, agrupadas en 24 especies y distribuidas en 28 departamentos, a lo largo de los valles interandinos del río Cauca y Magdalena. La distribución potencial, sugiere nichos asociados a las regiones de Amazonía y Orinoquía; bioregiones con amplios vacíos de colecta ubicadas dentro de las preferencias de distribución por rango altitudinal de las especies (0-500 m.s.n.m.). Las áreas con mayor riqueza son el centro occidente y nororiente del país con más de siete especies por zona. Pese a esto, el 80% de las especies están por fuera de áreas protegidas, lo que se agrava bajo los criterios de la IUCN, pues el 46% presentan algún grado de amenaza, además del alto porcentaje de endemismo (37,5%). Once especies son incluidas como nuevos reportes para 14 departamentos. Esfuerzos de colecta deben orientarse en las regiones de distribución potencial que poseen condiciones bioclimáticas óptimas para el desarrollo de las especies.
Show more [+] Less [-]Silicon Improves Cold and Freezing Tolerance in Pea Full text
2024
Ufuk Akçay | Hande Nur Kumbul | İbrahim Ertan Erkan
The most significant crop losses worldwide occur due to unfavorable temperatures such as heat, drought, cold, and freezing. Minerals like silicon can play important roles in the growth, development, and stress responses of plants. In this study, changes in stem/root length, dry weight, relative water content and silicon content, of peas under cold and freezing stress, as well as antioxidant system indicators such as proline, malondialdehyde, hydrogen peroxide, and chlorophyll levels, ion leakage, and the expressions of genes coding for the topoisomerase TOP2 and DNA helicase PDH47 enzymes, which play important roles in the replication, transcription, and repair of DNA molecules, were examined in root and stem tissues in the presence of two different concentrations of silicon. The results of the study showed that silicon application under cold and freezing stresses has induced various changes in pea metabolism, including increases in cell membrane integrity parameters and superoxide dismutase enzyme activity, as well as increase in the expressions of TOP2 and PDH47 genes. These changes have been found to have positive effects on the pea cold and freezing tolerance.
Show more [+] Less [-]Effects of Cold and Heat Stress on Egg Quality Traits of a Newly Developed Native Hybrid Layer Full text
2015
İsmail Durmuş | Serdar Kamanlı
ATAK-S is a newly developed native hybrid layer. Although the laying performance of this hybrid has been studied and determined, the performance response of the hybrid to different environmental temperature conditions is not known. This study was therefore undertaken to determine the effect of cold and heat stress on egg quality traits. Hens were divided into three different groups; control (20°C), low (12°C) and high (32°C). A total of 360 hens, with 120 in each of the groups, were used in the study. Hens were held in three tier battery cages in an environmentally controlled poultry house. The study lasted for 3 weeks. No differences were found among different groups in terms of shape index, albumen height and Haugh unit of the egg quality traits. It was found that the differences among the heat groups in terms of egg shell breaking strength, egg weight, shell thickness and yolk colour were significant and the value of these traits decreased under the heat stress conditions, whereas they were not affected from the cold stress.
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