Asparagus breeding national french work

International audienc

Evaluación de siete poblaciones de espárrago (Asparagus officinalis L.) Evaluation of seven asparagus populations (Asparagus officinalis L.)

Los materiales de espárrago (Asparagus officinalis L.) utilizados hasta el momento por los productores son introducciones realizadas por las casas semilleras y han sido seleccionados para satisfacer requerimientos del mercado de los sitios de origen. El objetivo del siguiente trabajo es evaluar siete poblaciones de espárrago (P1 a P7), con el fin de seleccionar genitores adecuados de manera de recurrir a la hibridación de ellos para obtener materiales adaptados a los requerimientos locales. Las evaluaciones se hicieron sobre plantas individuales, separadas por sexos y manejadas como espárrago blanco, durante los años 1993 y 1994, en el campo experimental de la Facultad de Ciencias Agrarias (Universidad Nacional de Rosario), ubicado en Zavalla, provincia de Santa Fe. La evaluación se realizó sobre planta individual, durante un período de 40 días de cosecha y con los datos obtenidos se realizó un ANOVA y un análisis de agrupamiento. Para elegir progenitores femeninos con altos rendimientos y rendimiento de mercado se determinó que se deberá recurrir a las P1, P2 y P3, las cuales presentan también alto número de turiones. Para altos peso medio y diámetro de turión, así como producción tardía, son indicadas las P5 y P7 como genitores masculinos, teniendo en cuenta que, mientras la P7 presenta bajo rendimiento, la P5 aportaría mejores producciones.<br>The materials of asparagus (Asparagus officinalis L.) that growers have in use are imported by seed dealers and have been selected according to overseas markets requirements. With the aim of selecting proper parents to use in a breeding program, seven populations of Asparagus officinalis (P1 to P7), all rised as white asparagus, were tested during 1993 and 1994, at the Experimental Field of the Facultad de Ciencias Agrarias (Universidad Nacional de Rosario) placed in Zavalla, Santa Fe, Argentina. The evaluation was made on individual plant in a 40 days of harvest period. ANOVA and a cluster analysis were made. In order to improve total and marketable yield, P1, P2 and P3 should be used as females regarding that these ones also have high spear number. To improve spears weight and diameter as well as late production, P5 and P7 are recommended as males, but it should be considered that P5 has a better yield performance

Characterization of Environments in Long-Term Multi-Site Trials in Asparagus, through Yield of Standard Varieties and Use of Environmental Covariates

International audienc

Critical Uncertainties and Gaps in the Environmental- and Social-Impact Assessment of the Proposed Interoceanic Canal through Nicaragua

The proposed interoceanic canal will connect the Caribbean Sea with the Pacific Ocean, traversing Lake Nicaragua, the major freshwater reservoir in Central America. If completed, the canal would be the largest infrastructure-related excavation project on Earth. In November 2015, the Nicaraguan government approved an environmental and social impact assessment (ESIA) for the canal. A group of international experts participated in a workshop organized by the Academy of Sciences of Nicaragua to review this ESIA. The group concluded that the ESIA does not meet international standards; essential information is lacking regarding the potential impacts on the lake, freshwater and marine environments, and biodiversity. The ESIA presents an inadequate assessment of natural hazards and socioeconomic disruptions. The panel recommends that work on the canal project be suspended until an appropriate ESIA is completed. The project should be resumed only if it is demonstrated to be economically feasible, environmentally acceptable, and socially beneficial

An integrated study on the characterization of freshwater lens in a coastal aquifer of Southern India

The hydrogeochemical characterization of groundwater helps to assess the trend of salinization and freshening of the groundwater. The present study was carried out to understand the lateral and vertical variation of groundwater salinity and the process of salinization and freshening of the groundwater in a coastal aquifer comprising a freshwater lens. The partially isolated unconfined aquifer selected for the present study is lying just south of the Chennai City, one of the densely populated cities on the east coast of South India. Critical problems affecting this aquifer include a thin aquifer which is connected/surrounded by saltwater on all the sides, overexploitation of the groundwater, surface impermeabilization due to increasing residential areas, and destruction of existing dune morphology by conversion of barren land to the residential area which causes a reduction in their barrier effect to seawater intrusion. The process of salinization and freshening of the groundwater was studied and monitored by using electrical resistivity survey and hydrogeochemical analysis. The vertical electrical sounding was carried out at 17 locations, and 400 water samples were collected and analyzed from 50 locations during the period from August 2008 to May 2010 for this study. The apparent resistivity values were analyzed and compared with groundwater quality to demarcate the zone of seawater intrusion. The regional flow direction of the groundwater is westward and eastward with respect to the central stretch and groundwater level ranges from 4.96&nbsp;m MSL at the dune morphology to 0&nbsp;m MSL along the boundary on all the sides. Base exchange index indicates that salinization trend in the northern part of the study area is due to the extensive groundwater pumping which increases the possibility of seawater intrusion. The increase of base exchange index towards southern part indicates a better groundwater quality of the aquifer due to proper land use practices. A strong trend of quality alteration is clearly visible from the base exchange index in response to the seasonal change between monsoon and dry season. In the western side, the monsoonal variation in the salinization and freshening of the groundwater was not noticed; however, the salinity is slightly higher than freshwater due to the presence of clay

Study of the somaclonal variation produced by different methods of polyploidization in Asparagus officinalis L.

Polyploid plants have been induced in different Asparagus officinalis L. breeding programs in order to obtain plants with improved agronomical traits, such as large spear diameter or segregation ratios with a higher number of males. The polyploidization methods can produce somaclonal variation in the polyploid plants obtained and, therefore, unwanted changes in the agronomical traits of the initial elite plants. We used two different polyploidization methods to induce polyploid plants from diploid genotypes of commercial varieties and tetraploid genotypes of the Spanish landrace “Morado de Huétor”. The first method was the culture of rhizome buds in the medium ARBM-3 (Asparagus Rhizome Bud Medium), supplemented with different concentrations of colchicine (0.1–0.75 g l−1) for 10 and 20 days. The best polyploidization rate obtained was 25 % (0.5 g l−1 colchicine for 10 days). The second method was the regeneration of polyploid plants from callus culture, resulting in a polyploidization rate of 40 and 12.5 % for the diploid genotype CM077 and the tetraploid genotype HT156, respectively. Additionally, we have developed a new protocol to separate the mixoploids generated into their different genetic components, obtaining plants with a unique ploidy level. EST-SSRs markers were employed to analyze the genetic stability of polyploidy plants. Somaclonal variation was not detected for polyploidy plants obtained through the culture of rhizome bud explants. Therefore, these polyploid plants should maintain the agronomical traits of the initial elite plants. However, somaclonal variation was detected in the polyploid plants regenerated from callus culture.Fil: Regalado González, Jose Javier. Instituto de Horticultura Subtropical y Mediterránea La Mayora; España. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Carmona Martín, E.. Instituto de Horticultura Subtropical y Mediterránea La Mayora; EspañaFil: Castro, P.. Universidad de Córdoba; EspañaFil: Moreno, R.. Universidad de Córdoba; EspañaFil: Gil, J.. Universidad de Córdoba; EspañaFil: Encina, C. L.. Instituto de Horticultura Subtropical y Mediterránea La Mayora; Españ