BANGLADESH JOURNAL OF FOREST SCIENCE
A Half-yearly Peer Reviewed Journal of Bangladesh Forest Research Institute
A Half-yearly Peer Reviewed Journal of Bangladesh Forest Research Institute
Antheraea paphia Linn. (Saturniidae :
Lepidoptera) is a wild silkworm that gives us
tassar silk of commerce. The dark buff-coloured
silk is coarse and very strong, but of inferior
quality a,s compared to that obtained from the
domesticated silkworm, Bonibyx niori. This wild
insect is not domesticated, and cannot be reared in
confinement on a commercial basis.
In 1999, some trees of a 3-year old telsur
(Hopea odorata Roxb.) plantation in the campus of
the Bangladesh Forest Research Institute,
Chittagong were found infested by a group of
wild silkworm. The larvae were found feeding on
the tender foliage of the upper canopy of the trees
and were kept under observation. They were pale
green with a yellow line at each side and rather
bulky, distinctly segmented and smooth-bodied
except for rows of ornamental metallic spotsand
tubercles bearing clusters of short spines (Fig. 1).
The full-grown larvae were about 10 cm long.
Pupation occurred in oval cocoons with a compact
surface (Fig. 2). The cocoons were formed in rolled
leaves orsuspended by a thick silken cord from a
twig. The cocoons were collected and reared to
adults which were identified as Antheraea paphia
Linn. (Saturniidae : Lepidoptera). The adult
female is a broad-winged moth with a wing-span
of about 12 cm. It is bright yellow with a circular
semi-transparent area or ‘eye’ on each wing
(Fig- 3)-
The toxic properties of petroleum spirit (40°-60°C) and water-soluble absolute
alcoholic extracts of the bark of Barringtonia acutangula (Gaertn.) were investigated on
laboratory animals. The petroleum spirit extract when administered intra-peritoneally
was found toxic to the experimental mice. The 24-hr LDW value was found 81.47 mg.kg’
1 body weight. The %2 value for the lethal dose was found significant at 0.1% level of
significance. The petroleum spirit and water-soluble absolute alcoholic extracts when
administered orally to rats showed some toxic properties but no mortality. The study
reveals that the petroleum spirit (40°-60°C) extract of the bark of Barringtonia acutangula
(Gaertn.) has a great prospect to decrease or substitute the use of synthetic pesticides,
especially the organophosphates.
The Sundarbans of Bangladesh, facing the Bay ofBengal, is the largestsingle tract
mangrove forest of the world. This natural forest has three watersalinity zonessuch as
less saline zone, moderate saline zone and strong saline zone. Golpata (Nypafruticans),
a palm species, grows naturally in patches along the stable banks of the rivers in larger
proportionsin the lesssaline zone of the Sundarbans. Thisspecies has been widely used
by the people of the entire south-western part of the country for thatching dwelling
houses. Experimental plantations of this species were established in the newly
accreted lands along the banks of the rivers in three salinity zones of the Sundarbans to
study itssurvival and growth. Fourmonths old seedlingsraised in the nurserybed were
used. Data on survival and plant growth (average leaf length and leaf number) were
collected after every three months for a period of 30 months. The highest survival
(65.35%) and plant growth (leaf length 290.67 cm and leaf number 6.80) were observed
in the less saline zone and the lowest survival (11.54%) and plant growth (leaf length
74.01 cm and leaf number 4.62) in the strong saline zone. The study shows that though
golpata can be grown successfully in the lesssaline and moderate saline zones, it grows
betterin the lesssaline zone of the Sundarbans. However, golpata shouldnotbe planted
in an area where heavy siltation occurs.
Sundarbans, the largest single continuous tract of natural mangroves in the world,
is endowed with a diverse group of plants and animals and has recently been given the
status of’World HeritageSite’ by the UNESCO.Thispaper gives a briefaccount of31 species
of insect pests attacking Sundarbans mangroves of Bangladesh. The pests include five
species of defoliators, three stem borers, eight fruit borers, two gall makers, one sap sucker,
one root feeder and 11 wood borers. These include 17 specks of Coleoptera, 11 species of
Lepidoptera, two species of Diptera and one species of Homoptera.
Two sap samples of Nypafruticans were collected in November 1996 and in April
1997 from the Chakaria Sundarbans for the production ofsugar, vinegar and alcohol. The
samples were first analysed to determine tire sugar contents by hand refractometer. The
first sample contained around 10.0% sugar, while the second contained about 8.0%.
Experiments were also conducted to produce vinegar trom the first sample and alcohol
from the second, each with and without addition ofsugar. Various amounts of yeast,such
as 0.2%, 0.6% and 1.0% (w/v) were added to determine the optimum yield of vinegar and
alcohol by fermentation process. It was observed that, in both the cases, addition of 0.6%
(w/v) yeast yielded the highest amount of acetic acid (4.3%) and alcohol (-5.0%) as
azeotropic mixture. There was about 0.2% increase in acetic acid yield with 0.6% (w/v)
yeast and further addition of 2.0% sugar to the original sample. The highest yield of
alcohol, 5.5% (as azeotropicmixture) was obtainedwhen the sap solution contained 13.0%
sugar and 0.6% (w/v) yeast. This shows thatN.fruticanssap may be a prospective source
for production of sugar, vinegar and alcohol in the country
This paper presents information about growth, harvesting ages and yields for
jalibet (Calamus tenuis’), kerakbet (C. viniinalis) and gollabet (Dacmonorops jenkinsiana)
raised in semi-evergreen/deciduous forests of Bangladesh. Clump expansion with
increasing age was highest for C. tenuis and C. viniinalis in Chittagong, and for D.
jenkinsiana inSylhet. Mean annual height increments ofmain shoot of a clump ofC. tenuis,
C. viniinalis and D. jenkinsiana were 0.94 + 0.08,1.11+0.09 and 1.45±0.11 m respectively.
Highest number of shoots per clump was noticed for C. tenuis in Sylhet followed by
C. viniinalis and D. jenkinsiana in Chittagong. Mean diameters of the main shoot of these
species were 1.6 ± 0.1, 2.14 + 0.1 and 3.01 ± 0.13 cm respectively. Wildings were found
under the clumps with varying numbers. The exploitable ages for C. tenuis, C. viniinalis
and D. jenkinsiana appeared to be 6-8, 9-11 and 10-12 years respectively. Further
information and studies are needed to determine the harvesting cycle and suggest a
management plan for rattans.
Several studies were previously conducted on pulping of jute plant by
alkaline processes. But the response of the plant to alkaline pulping is poor. In the
present study neutral sulphite anthraquinone (NS – AQ) process proved more
advantageous over alkaline processes. The process is capable of producing a
significantly higheryield compared to the alkaline processes. The physicalstrength
properties of NS – AQ jute plant pulp stand in between hardwood and softwood
kraft pulps. However, success of commercial utilization of jute plant in pulp
making largely depends on efficientmeans of collection, transportation and storage
of the plant. Hence, due attention to these problems must be given
Ipil-ipil {Leucaena leucocephala (Lam.) de Wit} is considered as an
outstanding tree because of its worldwide success as a highly nutritious forage
tree. Thisstudy is an attempt to determine suitable spacing formaximumbiomass
production. Widerspacing (60 cm x 60 cm) provided maximum seedling growth
(height 177.9 cm and collar dia. 15.3 mm) and biomass production (green weight
276.0 g/seedlingand dry weight 166.5 g/seedling) at the age ofnine months of the
seedlings. However, closerspacing (15 cm x 15 cm) produced significantly higher
biomass(greenweight 28.21 ton/ha and dry weight 11.68 ton/ha) on an area basis.
Small land holding farmers may rear their livestock by planting this legume and
harvesting under a ‘cut-and-carry’ system which will supply high quality forage
that uses to supplement low quality roughage such as crop residues.
The colonization status of arbuscular mycorrhizal (AM) fungi of Melia azedarach L.
seedlings grown from seven different types of pre-sowing treated seeds and the spore
population in the rhizosphere soils were studied. The percent root colonization varied
significantly and ranged between 14.81-95.0 in different treatments. The superior
seedlings showed heavy root colonization as compared to otherseedlings. The intensity of
colonization and spore population also varied significantly in different treatments. Spore
population was not correlated with the percent root colonization and seedling growth
parameters. Four AM genera such Glomus, Acaidospora, Entrophospora and Gigaspora were
identified from the rhizosphere soils of the seedlings. The importance ofAM fungi has been
ensured from this study for the primary establishment of M. azedarach seedlings in the
nursery
Physical and chemical properties of some soils from Madhupur rubber
plantation area in Bangladesh have been studied. Results of particle-size distribution,
oven dry/air dry ratio, field moisture capacity, pH, organic carbon, total nitrogen,
cation exchange capacity (CEC) and exchangeable cations of the soils on depth basis
have been presented. The nutrient contents of these soils have also been reported. With
respect to nutrient status and physico-chemical properties, these soils are considered
to have good potentiality and prospect for increased production of rubber, if proper
attention and management practices are adopted.
Welcome to the Bangladesh Journal of Forest Science (BJFS) – a leading platform for advancing the knowledge and understanding of forest science in Bangladesh and beyond. Established with a commitment to excellence, BJFS serves as a cornerstone for researchers, practitioners, and enthusiasts dedicated to the sustainable management and conservation of forest ecosystems.
