Genetic divergence between wild and cultivated pearl millets (Pennisetum typhoides) : 1. Male sterility

In two crosses between wild and cultivated pearl millets nucleo-cytoplasmic male sterile plants have been created by transfer of a cultivated genotype into a wild cytoplasm. The phenomenon is not reciprocal : the wild genotype placed in cultivated cytoplasm maintains an excellent male fertility. A completely male sterile BC7 line in wild cytoplasm background greatly resembling the cultivated parent, has been constructed from one of the two crosses. The genetics of its restoration seems to imply three independent genes (2 major and 1 minor). Restoration tests of this new male sterile line indicate that it is different from the three known male sterile sources A1, A2 and A3. Wild forms seem to possess a higher frequency of restorer alleles than cultivated forms, regardless of their geographical origins. (Résumé d'auteur

Comparaison entre relevés de 25 m2 et 100 m2 pour l’étude de la faune de la strate herbacée

Au cours de l’étude des peuplements animaux d’une savane de Côte d’ivoire par la méthode des carrés de ramassage, il a semblé utile de comparer deux surfaces usuelles : 25 m2 et 100 m2. Dans ce but, trois séries de relevés comprenant chacune un quadrat de 100 m2 et quatre de 25 m2 ont été réalisées en une seule matinée dans un même milieu. Il est apparu que les récoltes sur 25 m2 sont plus minutieuses et, en considérant les groupes zoologiques globalement, pas plus hétérogènes que celles sur 100 m2. L’étude spécifique de quelques groupes d’insectes montre qu’une surface de 100 m2 au minimum est nécessaire pour avoir une première idée des principales espèces. L’analyse de ces relevés montre aussi que la variabilité de densité des peuplements est très différente suivant les groupes. On peut supposer que les plus variables seraient de bons indicateurs écologiques.The results obtained by hand-collecting of Arthropods from quadrats of different size (25 m2 and 100 m2) have been compared. Collecting was done in Loudetici savanna on the same day and at the same time. Retter results are obtained using small (25 m2) rather than large (100 m2) quadrats, a greater number of small sized individuals being taken per unit area in the former compared with the latter. Sample variability is no higher in the smaller quadrats, and it is concluded that the best compromise between the cost and variance of daily sampling is attained by sampling from 4 to 6 areas, each of 25 m2

Recurrent phenotypic selection and recurrent selection based on combining ability in tetraploid bahiagrass

Paspalum notatum Flüggé is an apomictic grass used for forage and turf. The recent generation of a sexual synthetic tetraploid population of the species provides the uniqueadvantagetoexploitheterosisbyaccumulatingfavorableallelesthroughrecurrent selection cycles. The objective was to evaluate recurrent phenotypic selection (RPS) and recurrent selection based on combining ability (RSCA) as breeding methods. The best sexual genotypes in terms of warm-season growth from a sexual synthetic tetraploid population were selected by RPS and RSCA. The selected genotypes were polycrossed and two new sexual populations were created, which were crossed with superior apomictic genotypes. Both methods allowed obtaining families that were evaluated for summer, fall, and spring growth. Breeding values and heterosis were also calculated. Summer growth for RPS families was greater than for RSCA families (33.1 and 29.08 g plant−1, respectively); however, fall, spring, and accumulated growth were similar. The breeding value for RPS sexual parents was greater than for RSCA sexual parents for summer growth, whereas those for fall and spring growth were similar. A greater level of families with heterosis (80%) was observed for RPS than for RSCA (30%) for summer growth, whereas the levels for fallandspringgrowthweresimilar.Theseresultsindicatethatbothbreedingmethods were successful in improving tetraploid P. notatum. They increased the mean value of the progenies and produced families superior for forage yield by accumulating favorable alleles.Fil: Marcón, Florencia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Botánica del Nordeste. Universidad Nacional del Nordeste. Facultad de Ciencias Agrarias. Instituto de Botánica del Nordeste; ArgentinaFil: Martínez, Eric Javier. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Botánica del Nordeste. Universidad Nacional del Nordeste. Facultad de Ciencias Agrarias. Instituto de Botánica del Nordeste; ArgentinaFil: Zilli, Alex Leonel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Botánica del Nordeste. Universidad Nacional del Nordeste. Facultad de Ciencias Agrarias. Instituto de Botánica del Nordeste; ArgentinaFil: Rodríguez, Gustavo Rubén. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Investigaciones en Ciencias Agrarias de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Agrarias. Instituto de Investigaciones en Ciencias Agrarias de Rosario; ArgentinaFil: Brugnoli, Elsa Andrea. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Botánica del Nordeste. Universidad Nacional del Nordeste. Facultad de Ciencias Agrarias. Instituto de Botánica del Nordeste; ArgentinaFil: Acuña, Carlos Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Botánica del Nordeste. Universidad Nacional del Nordeste. Facultad de Ciencias Agrarias. Instituto de Botánica del Nordeste; Argentin

Frankel, O.H. & Hawkes, J. G. (Editors). — Crop genetic resources for today and tomorrow. Cambridge, University Press, International Biological Programme, volume 2, 1975

Pernès J. Frankel, O.H. & Hawkes, J. G. (Editors). — Crop genetic resources for today and tomorrow. Cambridge, University Press, International Biological Programme, volume 2, 1975. In: La Terre et La Vie, Revue d'Histoire naturelle, tome 30, n°1, 1976. pp. 154-155

An inheritance study of domestication in foxtail millet using an interspecific cross

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Comparaison de plusieurs indices de diversité dans l’étude d’un peuplement de Mantes

The biological diversity of praying Mantids has been analysed to illustrate some classical indices between stability and diversity on the one hand and the numbers of individuals and species on the other. A good description of the Mantid communities can be reached by using only two parameters : the «⍺», of Fischer for specific richness and the «E» of Margalef for interspecific relations.Gillon Yves, Pernès J. Comparaison de plusieurs indices de diversité dans l’étude d’un peuplement de Mantes . In: La Terre et La Vie, Revue d'Histoire naturelle, tome 24, n°1, 1970. pp. 54-61

Genetic divergence between wild and cultivated pearl millets (Pennisetum typhoides) : 1. Male sterility

In two crosses between wild and cultivated pearl millets nucleo-cytoplasmic male sterile plants have been created by transfer of a cultivated genotype into a wild cytoplasm. The phenomenon is not reciprocal : the wild genotype placed in cultivated cytoplasm maintains an excellent male fertility. A completely male sterile BC7 line in wild cytoplasm background greatly resembling the cultivated parent, has been constructed from one of the two crosses. The genetics of its restoration seems to imply three independent genes (2 major and 1 minor). Restoration tests of this new male sterile line indicate that it is different from the three known male sterile sources A1, A2 and A3. Wild forms seem to possess a higher frequency of restorer alleles than cultivated forms, regardless of their geographical origins. (Résumé d'auteur

Use of wild Setaria viridis (L.) Beauv. to improve triazine resistance in cultivated S. italica (L.) by hybridization

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