Desarrollo floral de los aguacates 'choquettes' y 'booth-8' en clima cálido: Parte II

to improve the efficiency of several cultural practices, such as pruning, fertilizer and plant bioregulators application, etc. is necessary to know the time when buds and shoots reach the stage of irreversible commitment to flowering (icf). the objective of this investigation was to establish the date when icf occurs in apical buds of spring and summer shoots of 'choquette' and 'booth-8' avocados. the study was conducted from 2004 to 2006 in one 'choquette' and one 'booth-8'orchards in the warm subhumid climate of jalcocotán, municipality of san blas, nayarit, mexico. time for icf was established by means of the type of growth produced (vegetative or floral) by apical buds of spring and summer shoots in response to biweekly treatments of bark ringing plus defoliation. the date of icf varied between the cultivars studied. the date of icf for the 'choquette' avocado was 15 november and there were no differences due to shoot age (spring or summer). for 'booth-8', the icf of summer shoots occurred by 30 november. macroscopic characteristics of apical buds irreversible committed to flowering were closed and pointed buds with partial senescence of bud scales.