The coconut odyssey - the bounteous possibilities of the ... - ACIAR

as resistance to lethal yellowing
disease and related pathogens.
Others show better tolerance of
drought, for example the Sri Lanka,
Cameroon and Brazil Green Dwarf
(a molecular study has shown
these to be very closely related). As
noted above, the fruit and nut of
the Dwarf are smaller than those of
the Tall used in plantations, which
makes a larger-fruited Dwarf variant
more attractive. Unfortunately, two
otherwise suitable large-fruited
Dwarf varieties, Malayan Green
and New Guinea Brown, have poor
drought tolerance.
Other variations in both Dwarf
and Tall palms include the nonbranching
fruit bunch, or Spicata
type, which has a greatly reduced
number of male flowers, while
the female flowers are all crowded
on a single flower stem. In a rare
type of palm in the Philippines,
the Makapuno type, the kernel is
replaced by a gelatinous mass with
a strong coconut flavour; this type
fetches a premium price for use in
ice-cream. A similar trait is known in
India, Indonesia and Sri Lanka, and
an isolated mutant of this type has
been observed in Solomon Islands.
�ailand has a prized type,
Aromatic Green Dwarf, with an
attractive aroma in the immature
husk. Keeping rats away from this
variety is a problem, as it is with
‘edible husk’ fruit found occasionally
in several countries.
�ere are many reports of particular
palms producing fruit of exceptional
medicinal value, especially in their
nut water (the coconut juice), but it
is hard to find proof of such claims.
Exploiting diversity with
hybrids
Hybrids between Tall and Dwarf
types have attracted much interest
among producers seeking high
productivity, especially of kernel and
oil. �ese hybrids, for which the
Tall parent has usually been chosen
because of its large fruit and local
adaptation, grow more vigorously
and flower sooner than the Tall
parent. �ey exhibit intermediate
trunk thickness and a moderate rate
of height increase, and are usually
more productive of kernel and oil
than either parent type.
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It is not yet known if they will
sustain production throughout a
long life, as large-scale planting of
hybrids began only in the 1970s,
but in the first 20 years they have
produced up to 30% more than the
related Tall in the same environment.
One theory proposes that the high
yield of the hybrid is based in part
on its low rate of trunk growth,
which allows more of the plant’s
resources to be allocated to fruit
production.
Hybrids usually also have a higher
proportion of kernel in the fruit than
either parent does, because both the
shell and the husk are thinner than
those of the Tall parent, while the
nut is larger than that of the Dwarf
parent. It is interesting to note
that the highest-yielding hybrids
are those with a large number of
smallish fruit.