General features of inflorescences
The position of inflorescences (at different maturity stages) in
the crown is illustrated Fig. 1. The entire developmental process
from floral initiation to maturation takes over two years.
Normally, up to stage −4 maturity (4 months before opening,
the spadices are ivory in colour and completely enclosed by the
subtending leaf base. Following exposure, the more mature stages
turn green in colour (Fig. 2A and B). The inflorescences are
tightly enclosed by the thin prophyll and thick peduncular bract
up to stage −4 and the bracts become fibrous with maturation. The
prophyll elongates and attains a maximum length of approximately
40–46 cm whereas the peduncular bract elongates rapidly
through the prophyll, reaching a maximum length of approximately
1.5 m. The inflorescence splits along the underside of the
peduncular bract to expose the rachilla (Fig. 2C).
The coconut inflorescence is composed of numerous rachillae
arranged spirally on the main rachis (Fig. 2D). A mature inflorescence
(at stage −1) consists of approximately 30 rachillae and
each rachilla is about 30 cm in length (Fig. 2E). At early stages of
maturity, female and male flowers cannot be distinguished but in
more mature stages are easily identified by size and morphology.
The structural complex of triads is present at the base of the
rachillae with a female flower flanked by two functional male
flowers (Fig. 2F). The latter normally mature first and open just
after the opening of inflorescence. The number of female flowers in
each rachilla varies from 0 to six. The male flowers occur in large
numbers (about 11,000 per inflorescence on average) and cover the
total length of rachillae. They are arranged in diads in the middle
part of rachilla (Fig. 2G) followed by solitary flowers (Fig. 2H)
towards the top of the rachilla. When mature, female flowers
(Fig. 2I) and male flowers (Fig. 2J) turn a brownish orange colour.