Phenologic aspects of the development of peach palm for heart of palm.

Abstract

Four heart of palm varieties of peach palm

(Bactris gasipaes Kunth) in four developmental stages (3, 6,

9 and 12 months), were studied with regard to their

phenological behaviour, to complement other works

previously conducted. The study began with the description

of the physical composition of the foliar heart of palm, which

shows that the number of embryonic leaves is higher than that

of the mature leaves, and that the proportion differs with the

varieties. It diverges from the 50:50 ratio found in adult

stems. It was found that the larger number of embryonic

leaves corresponds to the varieties with highest production.

Also, the weight of the foliar heart of palm is correlated to the

sheath weight of the spear leaf as well as to the weights of the

sheaths of all embryonic leaves, the useful embryonic leaf

laminas and the weight of the .dome. (upper part of the stem

where the embryonic leaves rest). The degrees of those

correlations vary with the varieties. Number of shoots

produced per plant at those stages, which is an agronomical

important characteristic of this palm, shows a correlation

with earliness and productivity. It is suggested, that axial

leave buds of juvenil whole leaves give rise to vegetative

shoots and those from mature composite leaves to

inflorescenses. The root, stem and foliar development keep a

very precise balance throughout the first 12 months. The stem

diameter and height are correlated with production and length

of the petiole of the older leaf, which is a practical prediction

parameter to be used. According to the results obtained, the

most useful parameters in a selection program of plant

breeding are: earliness and number of shoots production,

stem diameter and height, length of the petiole of the oldest

leave and succulence/firmness of the heart of palm.