Dr.M.Tajimul Haque
Senior Research Officer
BSRTI, Rajshahi.
Dr.M.A.Qader
Senior Research Officer
BSRTI, Rajshahi.
The experiment was conducted in pre-winter and post-winter seasons during the year 199-2001 using bivoltine silkworm race S98. Nutritional composition of mulberry leaves were estimated before and after adopting packages of practices in the mulberry field in different selected areas. Results revealed that nutrient contents viz.moisture, protein, total sugar, reducing sugar, starch and soluble carbohydrate contents were obtained higher in Domar area under Nilphamari districts followed by Modupur area of Tangil before and after adopting packages of practices in the mulberry field.
Quantitative charaters of silkworm viz.larval weight, shell weight, shell ratio, length of filament and cocoon yield/100dfls were recorded and found significantly(P<0.05)higher larval weight (41.60 g,wt)single cocoon weight(1.41 g), single shell weight(0.29g), shell ratio(20.52%), length fo filament (924.60m) and cocoon yield/100dfls (72.07kg) in treatment T1 and seasons S3 in Domar area of Nilphamari district followed by Modupur area of Tangil district, while lower performance was recorded Bochagonj area under Dinajpur district. Similarly significant(P<0.05) higher raw silk%(18.7), reelability%(75.33), tenacity(3.55g/d), elongation(19.80)cohesion (44.56)and lower renditta(9.11) were obtained in the same treatment, season and area followed by Modupur area. Significant(P<0.05) seasonal and location variations were also observed in respect of cocoon characters raw silk productivity and quality.
Appropriate technologies, productivity, silk, cultivation practices
Bangladesh Sericulture Research and Training Institute.
Crop-Soil-Water Management
a)Improvement of mulberry plants and multiplication of bivoltine/hybrid silkworms for the target sericultureists.
b)Strategies of micro-environment management of bivoltine/hybrid by the target sericulturists.
c)Selection and multiplication of viable parent lines of bivoltine/hybrid suitable for Bangladesh condition (ie. four seasons).
d) Improvement of micro-environment in mounting room.
e) Quantitative and qualitative improvement of commercial cocoons for more economic returns to the sericulturists.
This is actually an on farm research project where certain packages were applied during rearing period to establish several acclimatized bivoltine breeds in the agro ecological conditions of Bangladesh. Selected bivoltine varieties S98 were multiplied at the basic multiplication farm under BSRTI, Rajshahi from which required DFLs (10,000 DFLs/year) were prepared following Narasimhanna (1988) in producing processing and preservation of these eggs.
Bivoltine varieties normally thrive well within temperature range 24-28 o C and relative humidity range 70-85%. In Bangladesh two seasons viz. Pre-winter months from October- November and Post-winter months from February-March more or less satisfy above situations and were considered for the study.
48 silkworm rearing farmers were selected randomly from six different locations of Bangladesh like Natore, Bogra, Dinajpur, Nilphamari, Panchagor andTangail and 8 farmers from each locations. The farmers mostly landless and poor who used to rear silkworms in their dwelling house. These house were repaired/ restructured so as to facilitate better aerations and protections against sun, rain, and pest/predators. Normally these factors are overlooked by the farmers rendering reasonable loss during rearing.
Before starting the project work required rearing equipments like Dalas,Chandrakis and other necessary accessories were supplied to each individual farmers. Similarly strict sanitation and disinfection were done before and during rearing which is the most important and vital consideration for bivoltine management. Standard methods (Ullal and Narasimhanna 1978), Jolly and ESCAP Manual 1993) relating to bivoltine rearing were adopted through practical demonstration and training to the farmers during the project tenure.
At the same time certain packages viz. Mulberry packages+ silkworm rearing technique (designated as treatment T1) and Normal rearing (designated as T0 which is considered as control) were considered as treatments for silkworm rearing. Details of the above packages (Treatments) are described in materials and methods of silkworm rearing section.
Annual Report of BSRTI, January, 2002.
2000000.00
Treatment T1 (Mulberry package of practices + silkworm rearing technology) showed better performance in respect of the quantitative characters of bivoltine silkworm, raw silk productivity and quality in season S3 (Agrahayoni crop) compare to control (T0) treatment in Domar area under Nilphamari district. So treatment T1 may safely be recommended for adopting in commercial rearing of Bivoltine silkworm race in the field level for quantity and quality silk production in Bangladesh.