Bamboo
42 BANO BIGGY-‘N PATRIKA
i Revised version of the paper presented at the Third Annual Bangladesh Science
blight causing severe mortality, particularly of young
culms, in the village groves of Rajshahi district of Bangladesh is
reported. A brief history of the outbreak of the disease is noted,
A review of bamboo diseases is provided. Symptoms and observed
mode of infections are recorded. Four fungi have been isolated from
diseased bamboo samples. The pattern of isolation strongly suggests
that Conlothyrium fuckelil Sacc. is responsible for the blight.

The paper critically discusses the methods so far developed for
determining the best rotations (years from planting to final cutting)
for forest plantations in order to help professional forestry personnel
to determine the appropriate growing periods for Bangladeshi forest stands.
It is observed that most rotation models which are in use place
a lot of emphasis on the needs of wood producers. The needs of
the industries and other users generally receive less attention, Recent
developments abroad have attempted to rectify this situation. It should
be borne in mind, however, that no single method can be considered
to meet all our needs even for public investment purposes. We are
suggesting means to select the models consistent with maximum
economic growth resulting from income and employment effects on
the nation as a whole. The analysis also presents techniques to decide
the time of the final cutting decision at the end of the predicted
rotation in view of specific changes in the economic ‘climate and
other conditions.

Rhizome assemblies and clump form and growth of nine arboretum
grown bamboo species have been studied. Rhizome stalk has been
found to play an important role in determining the form, shape and
growth of clumps. This is due to not only the characteristic length
of the stalk in some species but also its role in orienting the rhizome
in relation to the centre of the clump and the mother culm in general
and the line of gravity in particular. In areas where bamboos are
worked heavily it is the rhizome stalk that is first affected and may
result in congested clumps in species otherwise monopodial or
loosely tufted.
Rhizomes are commonly attacked by pathogenic soil
ganisms, Parts like rhizome stalks, whole
bud of the rhizome may be partly or wholly consumed or otherwise
become inoperative and although these parts contribute to (he •• development
of rhizome assembly they do not contribute towards the growth
of clump. This reduces the rate of growth of clumps considerably.
Irrespective of species, only 8 percent of the buds develop into
normal culms, 77 percent remaining dormant and 15 percent are damaged
by pathogenic soil mlcrooganisms. It has been concluded tha- application
of antipathogens individually or in combination with fertilizer will
ameliorate the conditions of growth and considerably increase the
outturn.

Please visit direct the article as shared PDF

This paper deals with the iron status of different species of banana
leaves ; the effect of application of sulphur in sail on iron mobilization
and the effect of injection of iron salt solution on iron absorption by
banana leaves.
IRON STATUS OF BANANA LEAVES AND
RESPONSE OF SULPHUR APPLICATION
ON IRON UPTAKE1

Soil and leaf samples were collected from the groves of five edible
banana species grown in a green house, SoiI around the selected
banana plants was treated with sulphur both in the plots and in pots
aop’ying 100, 200 and 300 kg of sulphur per hectare. Two ml of
FeSO4 solution (5000 ppm) was injected on tha pseudosten at tha
base of tha third ycungest leaf. After four weeks, scil and leaf
samples were collected for analysis. Sunflower seedlings grown under
similar sulphur treated conditions were collected efter 20 days.
It was revealed from the results of the analytical data that iron
content in banana leaves vary from one species to the other. But
most of the species selected for this work contained higher amount
of iron in leaves compared to the iron content of sunflower seedlings.
The injection of FeSO4 solution in the pseudostems of iron deficient
banana plants gave expedited response in iron absorption by leaves
compared to the application of sulphur in soil which was done for
increasing the mobilization of iron.

Shrinkage and density were studied for Teak (Tectona grandls) of
five age groups ranging from 20 to 60 years at three height positions.
Linear shrinkages were evaluated from green condition to 15 and O
percent moisture contents. Density was determined on the basis of
green and ovendry volumes. Shrinkage and density were found to be
Independent of the height of the stem. The overall shrinkage and
density were affected by the age factor. The variations in the average
values of different age groups were, however, not observed to be
significantly different in all cases.

CIvit ( Swlntonia florlbunda ) veneer,
dry (1J—12 percent moisture content)
boric acid and 1.9 percent
for 10, 25 and 40 minutes,
three-ply plywood.
1.5 mm thick, both green and
were soaked in 1 25 percent
borax solutions separately at 90° —100°C
These were conditioned and glued into
with a ureaformaldehyde adhesive fortified with
melamine, for producing boil-resistant glue-bond. Plywood shear test
samples were prepared and tested in both dry and wet (boiled in water
for six hoyrs and tested while wet) states.
Dry shear tests show that green veneers treated with both boric
acid and borax, and dry veneers treated with borax had the higher
bond strength, while the longest treating time (40 minutes) had the
lowest bond strength, all the differences being significant at the 5%
level. The wet test shows significant differences at the 5% level
between the preservatives, borax treatment producing better bond
strength However, all the treatment combinations resulted in adequate
bond strength for the type of plywood produced.

Th© lack of knowledge of treatability of timber species with
pressure method may result in poor treatment in reipect of penetration
and retention of the preservative chemical Inwood. This knowledge
for our indigenous timber species was not ascertained before. The
relative penetrability of nineteen timber species was, therefore,
determined with Lowry empty cell process using 40 r 60 creosote
and light diesel oil mixture.
Specific gravity of species did not seem to have any bearing
on the penetration cf preservative. Grain structure and presence of
tyloses appeared to be correlated with penetrability of the wood.
The species were classified into four treatability groups according
to the degree of heartwood penetrability.

Please visit the direct article as shared PDF

Paper pulps have been prepared from Gamar (Gmelina arborea, Roxb.)
wood of four age groups by the kraft process. Cooks were made with
active alkali and sulfidity ranging from 14,94 percent to 21.05 percent
and 14,12 percent to 20,12 percent respectively at 170° C, The best
pulp was obtained with 16 years old gamar wood at 14,94 percent
active alkali and 14,57 percent sulfidity under optimum condition.
Pulp-yield varied from 40,86 percent to 49,35 perecnt at various ages.
The physical strength and other properties of Gamar kraft pulp compared
favourably with those of other hardwood pulps prepared in the Forest
Research Institute, Chittagong,