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414 pages, Los fondos de la ría de Vigo : composición, distribución y origen del sedimento / Federico Vilas Martín, Daniel Rey García, Belén Rubio Armesto, Ana M. Bernabeu Tello, Gonzalo Méndez Martínez, Ruth Durán Gallego, Kais Jacob Mohamed Falcón. Hidrografía y dinámica de la ría de Vigo : un sistema de afloramiento / Gabriel Rosón Porto, José Manuel Cabanas, Fiz Fernández Pérez (http://hdl.handle.net/10261/115885). Biogeoquímica de la ría de Vigo: ciclo de las sales nutrientes ; trampa/sumidero de CO2 / Carmen González Castro, Aida Fernández Ríos (http://hdl.handle.net/10261/116063). El plancton de la ría de Vigo / Francisco Gómez Figueiras, Ana Miranda, Isabel Riveiro Alarcón, Alba Ruth Vergara Castaño, Cástor Guisande (http://hdl.handle.net/10261/116072). Episodios de fitoplancton tóxico en la ría de Vigo / Beatriz Reguera Ramírez, Laura Escalera, Yolanda Pazos, Ángeles Moroño. Contaminación / Juan José González, Cristina Álvarez, Ricardo Beiras García-Sabell, Maria Victoria Besada Montenegro, José Fumega, María Ángeles Franco Hernández, Mariano Gómez, Amelia González Quijano, Teresa Nunes, Ricardo Prego Reboredo, José Antonio Soriano Sanz, Lucia Elisa Viñas Diéguez (http://hdl.handle.net/10261/116066). Explotación: pesca, marisqueo y acuicultura en la ría de Vigo / José Benito Peleteiro, Valentín Trujillo, Rafael Bañón Díaz, Jorge Ribó, Mercedes Olmedo, Blanca Álvarez Blázquez, José Luis Rodríguez, Juan Pazó, Juan José Otero. Impacto del hombre sobre el ecosistema de la ría de Vigo: hacia una gestión integrada / Ángel Guerra Sierra, Santiago Lens, Francisco Rocha Valdés (http://hdl.handle.net/10261/116069). Valoración económica del uso recreativo y la conservación / María Xosé Vázquez Rodríguez, Albino Prada Blanco

17 figures, 8 pages, 1 table, Fish in which gynogenesis has been induced have all their chromosomes inherited from the mother and, if females are the homogametic sex, they usually are all females. Because turbot females grow faster than males, the production of all-female populations is highly desirable. The sperm of turbot is of poor quality and its larvae are small and fragile. These circumstances represent a challenge for the induction of gynogenesis in the turbot. As a first step towards this goal, effective conditions for the induction of gynogenesis through UV irradiation of sperm followed by a cold shock were established. When diluted 1:10 with Ringer-200 saline solution and placed in a thin layer (~0.3 mm), a dose-dependent effect of UV light on sperm motility was found. The dose at which both the amount of motile sperm and the duration of sperm motility was reduced to 50% of the original value (ID-50) was ~28,000 erg mm−2. A typical Hertwig effect was elicited with a dose of 30,000 erg mm−2. The resulting embryos exhibited the typical “haploid syndrome” and died shortly after hatching. Application of a cold shock (−1 to 0°C for 25 min starting at 6.5 min after fertilization) to activated eggs with UV-irradiated (30,000 erg mm−2) and diluted (1:10) sperms restored diploidy and resulted in the production of gynogenetic diploids (2n=44 chromosomes). These conditions were used in a pilot-scale experiment and found effective in inducing gynogenesis in ~47,000 eggs. The rate of gynogenesis induction was 100% as verified by an analysis with microsatellite DNA markers. Survival of the gynogenetics was approximately 10% of diploids at 6 months of age, although growth was similar during this period. If this species turns out to have female homogamety, as is the case in most pleuronectiformes examined so far, the method presented here is the first necessary step for the production of all-female populations of this economically important species, Research funded by Spanish Government CICYT grant MAR95-1855 to P.M.