The picture above is a very distinct ginger planted in Forest Research
Centre, Kuching, Sarawak. Gingers, from the family Zingiberaceae,
are one of the most amzing components of the plant wealth in Malaysia,
Singapore and neighboring countries. Gingers are an unmistakable life
form and their diversity and biology have still not been completely
understood or well documented. For non-specialists, like me, it is very
hard for me to find any easily accessible
published material, outlines of their botany and their fascinating
development form. The word “ginger” truly refers to the edible ginger
of commerce known in Malay language as halia and
botanical name as Zingiber
officinale.
Whilst “gingers” is a general term for members or species of the
Zingiberaceae family. This family comprises about 1200 species of which
about 1000 species occur in tropical Asia. By far the richest area is
the Malesian region, a floristically distinct rich
region, which include Borneo, place that we have visited during the
course. Gingers in Borneo are still very insufficiently known and
largely under explored, therefore many new species were found each
years, thus increases the total species of gingers in this region.
Family Zingiberaceae are part of the order Zingiberales, which form an
unique isolated group among the monocotyledons. The main difference
among the eight generally recognized families within Zingiberales, is
their morphological character, with five stamens or one stamen.
Musaceae,
Lowiaceae, Heliconiaceae and Strelitziaceae are the four families with
five stamens, regarded as an older line of evolution. While,
Zingiberaceae, Costaceae, Cannaceae and Maranthaceae are more advanced
groups, which the non-functional stamens have been developed as
petaloid staminodes, with only one sterile stamen. Until lately, family
Costaceae were classified as Costoidae, a subfamily of the family
Zingiberaceae. Generally, the presence of essential oils and the
distinct arrangement of leaves (spirally), apparently well
differentiate the Zingiberaceae from the Costaceae. Below is a picture
of Costus sp.
taken from Maliau Basin Conservation Area, on our first day hike to
Ginseng Camp.
Zingiberaceae
vary in height and size, with
sometimes can grow up to 8 m high, others can be as small as 10 cm or
less. All ginger species are perennial herbs and rhizome (modification
of stem underground) present in all species. In some cases, the rhizome
is raised above the ground forming stilted-root, such as Hornstedtia sp.
Almost all gingers have alternate leaves arrangement (on the same
plane), shealth
below the leaf base, bracts arise from the main axis or branches, one
fertile stamen and inferior ovaries. However, within the family, leaf
blade symmetry or asymmetry, present of leaf hairs, colors of leafy
shoot and leaf
blade, inflorescence location, bract shape and arrangement, lip shape
and divided lip, present of elongated anther crest or filament, and dry
or fleshy fruit capsules can be used to differentiate between genera
and species. This morphological feature have been used to classified
all the gingers recorded from the course into genera or species if
possible.
One
of our task for the course was to choose a focal taxon, which we have
to look carefully at a group of related species to become an amateur
taxonomist and field naturalist. For my focal taxon, I chose family
Zingiberaceae. The reason why I chose this family because, I have never
knew that ginger that I ate everyday produced such an attractive
flower. All together 36 species of either flowering or
fruiting gingers were observed from each forest site (Lambir, Niah,
Gaya,
Sepilok, Deramakot, Kinabalu and Maliau Basin). Digital records and
detailed field descriptions and drawings, for each observed species
were recorded for latter use. Observations were made according to the
species distributions, habitats, ecological, behavioral,
morphological phylogeny and also their taxonomic. For many cases, inflorescence of gingers is a very important character
in order to classified gingers into genera or species. Only either
flowering or fruiting gingers were used in the cladistic analysis and
treeview. Fortunately, 26 species
with sufficient field character recorded were listed out and a mesquite
matrix were build for analysis on
their ancestral evolution relationships by using Mesquite software. A
phylogeny tree, based on morphological characters, for all chosen
gingers were build by using phylip 3.67 software and analysis by using
Mesquite to see their ancestral evolution and cladistic analysis.