Direct Somatic Embryogenesis in Carica papaya L. Genotypes for Genetic Modification Purposes.

This chapter presents an efficient protocol for regenerating Carica papaya plants via somatic embryogenesis from immature zygotic embryos from economically important papaya genotypes. To achieve regenerated plants from somatic embryos, in the present protocol, four induction cycles are required, followed by one multiplication cycle and one regeneration cycle. With this optimized protocol, 80% of somatic embryos can be obtained in only 3.5 months. At this stage, calli containing more than 50% globular structures can be used for transformation (via agrobacterium, biobalistics, or any other transformation method). Once transformed, calli can be transferred to the following steps (multiplication, elongation, maturation, rooting, and ex vitro acclimatization) to regenerate a transformed somatic embryo-derived full plant.

[Not Available]. / La fréquentation d'un service éducatif préscolaire : un facteur de protection pour le développement des enfants de familles à faible revenu?

OBJECTIVES: Describe the preschool education of children in educational services. Study the effects of components of preschool educational service attendance on the development of kindergarten children, based on income. METHOD: A sample of 1,184 children was extracted from a survey frame that included Montréal children assessed in the 2012 Québec Survey of Child Development in Kindergarten (2012 QSCDK). Data collected from the parents of these children allowed us to document the following components of educational service attendance (independent variables): longitudinal profile of the service used; age at entry; duration; average weekly attendance; and cumulative time. Linking QSCDK data provided a measure of development of children in kindergarten (dependent variable). Various logistic regression models using different combinations of components of educational service attendance were tested. Akaike information criterion enabled us to select the model that best explains the data. RESULTS: Children from low-income families are proportionately fewer to attend a preschool educational service than children from better-off families (79.6% vs. 90.5%; chi-square test (1df), p < 0.001). Children from low-income families who attended only an early childhood centre (centre de la petite enfance) are less likely to be vulnerable in two or more domains of development compared to their peers who did not attend educational services (OR 0.23; CI: 0.06 ­0.92). Children who started attending an educational service before the age of 12 months are less likely to be vulnerable in two or more domains of development (OR: 0.38; CI: 0.18­0.81). CONCLUSION: Attending an early childhood centre (centre de la petite enfance) is beneficial to the development of children from low-income families.