Propagation potential of commercial pineapples and impact of the subculture interval on production planning
ABSTRACT Measuring the propagation potential of any variety, considering micropropagation to obtain the seedlings, has received little attention from researchers. The use of unusual statistical techniques, such as geometric growth rate and exponential regression, can produce important information for planning and applying subcultures based on their in vitro behaviour, which may indicate the need to improve the protocol and to better understand the effects of interval trials and subcultures. The aim of this study was to evaluate the effects of three different subculture intervals on the propagation potential of commercial pineapple cultivars, with the aim of optimising micropropagation protocols and planning for seedling production on a commercial scale. Axillary buds from the Perola, BRS Imperial and Smooth Cayenne cultivars were used for in vitro establishment and multiplication in trials with a subculture interval of 30, 45 and 60 days, in six subcultures. The BRS Imperial cultivar had the best results in the 30-day trial. Although the number of shoots increases as the subcultures progress, the propagation potential is lower. Longer subculture intervals show lower shoot production and propagation potential, as demonstrated by the geometric growth rate and the Poisson log-linear models. The trials and statistical tools employed showed that the protocol needs adjusting to improve production in the Smooth Cayenne cultivar, which had the lowest propagation potential.