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Effects of forestry host plants, rearing seasons and their interaction on cocoon productivity of tropical tasar silkworm, Antheraea mylitta in uttarakhand
Effects of forestry host plants, rearing seasons and their interaction on cocoon productivity of tropical tasar silkworm, Antheraea mylitta in uttarakhand
International Journal of Industrial Entomology. 2015. Jun, 30(2): 31-39
Copyright © 2015, Korean Society of Sericultural Science
  • Received : April 04, 2015
  • Accepted : June 06, 2015
  • Published : June 30, 2015
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About the Authors
N.K. Bhatia
Regional Sericultural Research Station, Central Silk Board, Ministry of Textiles, Govt. of India, Sahaspur- 248 197, Dehra Dun, Uttarakhand, India.
nkb1123@rediffmail.com
Mohd. Yousuf
Forest Entomology Division, Forest Research Institute, New Forest - 248006, Dehra Dun Uttarakhand, India.
Abstract
Antheraea mylitta Drury (Lepidoptera: Saturniidae) is a commercial silk producing forest insect of India, but it has never been experimented in Uttarakhand state in spite of the huge availability of its forestry host plants. This is the first study on A. mylitta in Uttarakhand. The goal of this study is to introduce forest based commercial rearing of A. mylitta , in tropical forest areas of Uttarakhand to reduce poverty among forest dependent people. In current study, we assessed the effect of seven forest tree species, rearing seasons, and their interactions on cocoon productivity of Daba (bivoltine) ecorace of A. mylitta in the New Forest of FRI, Dehra Dun during 2012 and 2013 and collected the data that was analysed by two-way completely randomized block factorial design. Post HOC Tukey's HSD test was carried out to compare the homogeneous pairs of means. We also carried out Evaluation Index analysis to rank the tested forestry host plants for better growth and development of A. mylitta under the climatic condition of Uttarakhand. Analysis of variance indicated that cocoon yield of A. mylitta differed significantly between rearing seasons (DF=1, F=88.24, p <0.05) and host plants (DF 6, F= 368.63, p <0.05); however, their interactions were found insignificant (DF=6, F=0.99, p >0.05). In first rearing season of July-August, there was higher cocoon yield than the second season of September-November. Results indicated that Terminalia alata fed larvae showed significantly higher cocoon yield (164.11 cocoons/300 larvae); followed by, T. tomentosa (148.89 cocoons), T. arjuna (140.00 cocoons) and Lagerstroemia speciosa (129.47 cocoons) fed larvae. Whereas, Lagerstroemia tomentosa fed larvae that was used by the first time in India, showed lowest cocoon yield (48.81 cocoons), followed by T. chebula (72.53 cocoons) fed larvae. Cocoon yield of T. tomentosa and T. arjuna fed larvae of A. mylitta did not differ significantly with each other.
Keywords
Introduction
Antheraea mylitta Drury (Lepidoptera: Saturniidae) is a commercial silk producing polyphagous forest insect of India and many poor people in tropical and subtropical forest areas of Bihar, Jharkhand, Chhattisgarh, Madhya Pradesh, Odisha, Andhra Pradesh, Uttar Pradesh Maharashtra and touching the fringes of West Bengal commercially rear its larvae on different forestry host plants for small household income twice or thrice in a year ( CSB, 2012 ). Literature indicates that in recent years, many actions for sustainable exploitation of forest resources have been undertaken ( Muafor , 2012 ), but only few study are concerned with commercialization of forest insects to reduce poverty in forested area ( De Foliart, 1992 ). Because, many people still consider insects mainly as a pest; however, they are less aware of the poverty alleviation potential of commercial forest insect like A. mylitta ( Bhatia and Yousuf, 2013 b ).
Historically, foundation for the study of insect-host plant relationships was clearly defined by Charles T. Brues in 1920’s ( Brues 1920 and 1924 ); however, there is no reference on effects of forestry host plants, rearing seasons and their interaction on cocoon productivity of tropical tasar silkworm, A. mylitta in any of the Himalayan states of India, including Uttarakhand. It is known that cocoon crops of forest silkworms are influenced by the season and the host plants ( Venugopal and Krishnaswami, 1987 ). The cocoon of A. mylitta shows considerable variations in their colour, size, shape, pupal weight, shell weight, and the silk output ( Jolly ., 1974 , 1979 ) and such variations mainly occur due to climatic conditions, food plants and altitude ( Nayak and Guru, 1998b ). Several workers have reported that host plants influence the larval weight gain, survival percentage, relative growth rate, pupal weight, adult emergence, and fecundity of different lepidopterans ( Basu, 1944 ; Srivastava, 1959 ; Thobbi, 1961 ; Pandey ., 1968 ; Singh and Byas, 1975 ; Dubey ., 1981 ).
In Uttarakhand, rearing of A. mylitta has never been tried in spite of the huge availability of its forestry host plants in tropical forest areas up to an altitudinal range of 610 meter ( Thangavelu, 2004 ). We are concerned to introduce forest based rearing of A. mylitta , as a new forest insect industry in tropical forest areas of Uttarakhand. We believe that introduction of A. mylitta in tropical and subtropical forest areas of Uttarakhand can help in poverty mitigation. We also hypothesize that introduction of A. mylitta may revitalize the sericulture scenario of Uttarakhand by adding one more variety of natural silk in its export basket. Studies have also indicated that when forest dependent people are associated with forest insect industry like rearing of A. mylitta , such income generating activity links livelihood with forest conservation and improves the conditions of forest ( Bhatia and Yousuf, 2013 a ). This paper deals with effect of forestry host plants, rearing season and their interaction on cocoon productivity of A. mylitta in Dehradun, Uttarakhand.
Materials and Methods
- Out door rearing ofA. mylittaon seven forestry host plants
We investigated the effect of seven forestry host plants ( Lagerstroemia speciosa, Lagerstroemia tomentosa, Terminalia alata, Terminalia arjuna, Terminalia bellirica, Terminalia chebula and Terminalia tomentosa ), rearing seasons and their interactions on cocoon productivity of Daba (bivoltine) ecorace of tropical tasar silkworm, A. mylitta at New Forest, FRI, Dehradun Uttarakhand ( Fig. 1 ), which is situated at 30° 19’ 56.21” N to 30° 21’ 5.35” N and 77° 58’ 56.81” E to 78° 0’ 59.73” E at 640.08 AMSL. The climate of New Forest, Dehra Dun is moderate due to its location at foot of the Himalayas ( WMD, 2011 ). After carrying out survey of the New Forest and getting administrative approval from the Director, FRI, Dehra Dun, four outdoor experimental rearings of A. mylitta ( Fig. 2 to 4 ), each in July-August and September-November were conducted during the year 2012 and 2013 as per the improved rearing technology of Mathur . (1998) and data were collected as per the experimental protocol of the study.
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Map of the study site
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(a). Hatching of A. mylitta, (b). Just hatched larva, (c). Brushed larvae, (d). First instar larvae after 24 h, (e & g). Eaten leaves of L. speciosa and (f & h). First instar larvae before moult.
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(a & b). Moult out 5th instar larva, (c, f, g, h). Grown up fifth instar larva, (d). 5th instar larvae feeding on Terminalia tomentosa and (e). 5th instar larvae feeding on T. bellirica.
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(a). Beginning of cocoon spinning by grown up 5th instar larva, (b). Formation of hammock, (c). Spinning inside the cocoon, (d). Fully formed cocoon and (e). Harvested cocoon of A. mylitta from New Forest, FRI, Dehradun.
- Statistical methods and analysis of Data
Tested forest tree species were taken as treatments, so there were 07 treatments, and the number of replications was 06. Normality of data was checked before to the statistical analysis. Descriptive statistics were calculated by using Microsoft Excel. Data of first and second rearing seasons were combined together, then treatment wise descriptive statistics were calculated and mean tables were prepared. A two-way completely randomized block factorial design was used to test the significance of difference in the means of variable. We did Factorial ANOVA by using advance statistical software, STATISTICA 10. Rearing season, host plant and their interactions were treated as the main (fixed) effects and cocoon productivity served as dependent variables for block effect. The level of significance was fixed at p =0.05. Post HOC test was carried out by using Tukey’s HSD test to compare the homogeneous pairs of means.
- Evaluation Index (EI)
Evaluation Index [EI] shows an aggregate unit of cocoon yield of A. mylitta reared on a particular host plant in different rearing seasons, which was ca1cuated as per the procedures outlined by Mano . (1993 , 1998) . For cocoon yield, EI of 50 or more than (>) 50 is considered suitable.
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Where , A = Mean of a variable on a particular treatment; B = Over all mean of that variable on all the treatments; C = Over all standard deviation of that variable on all the treatments; 10 = Standard unit and; 50 = Fixed value
Results
Analysis of variance for the effect of rearing seasons, host plants and their interactions on cocoon yield (number)/300 larvae of A. mylitta presented in Table 1 reveals that cocoon yield of A. mylitta differed significantly between rearing seasons (DF=1, F=88.24, p <0.05) and host plants (DF 6, F= 368.63, p <0.05); however effect of interactions between rearing season and host plants on cocoon yield was found insignificant (DF=6, F=0.99, p >0.05).
Analysis of variance for the effect of rearing seasons, host plants and their interactions on cocoon yield (number)/300 larvae ofA. mylitta
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Analysis of variance for the effect of rearing seasons, host plants and their interactions on cocoon yield (number)/300 larvae of A. mylitta
Fig. 5 indicates that in first rearing season, cocoon yield was significantly higher on all the forestry host plants as compared to the second rearing season. Effect of rearing seasons and host plants on cocoon yield (number) / 300 larvae of A. mylitta , reared on different host plants showing in Table 2 reveals that in first rearing season, T. alata fed larvae showed highest yield of 171.58 cocoons/300 larvae, followed by T. tomentosa (156.75 cocoons), T. arjuna (148.17 cocoons) and L. speciosa (133.17 cocoons) fed larvae. Whereas, L. tomentosa fed larvae showed the lowest cocoon yield of 57.69 cocoons followed by T. chebula (83.54). The corresponding higher values in second rearing season were 156.64, 141.03, 131.81 and 125.77 cocoons/300 larvae fed on T. alata, T. tomentosa, T. arjuna and L. speciosa , respectively.
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Effect of rearing seasons and host plants on cocoon yield of A. mylitta.
Effect of rearing seasons and host plants on cocoon yield (number) / 300 larvae ofA. mylitta, reared on different host plants
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*Values represent mean of six replications ; S.E.- Standard Error; CV – Coefficient of Variation; Min.- Minimum; Max.- Maximum
Results of Tukey HSD test presented in Table 3 for the effect of rearing seasons on cocoon yield (number) / 300 larvae of A. mylitta , reared on different host plants show that rearing seasons had significant impact on cocoon yield, as overall mean of cocoon yield differed significantly with each other and demonstrated two homogeneous groups of means. Further, Tukey HSD test for the effect of host plants on cocoon yield of A. mylitta presented in Table 4 indicated six homogeneous groups of means that differed significantly from one another. Table indicates that cocoon yield of T. tomentosa (148.89) and T. arjuna (139.99) fed larvae did not differ significantly with each other and formed one homogeneous group. Table 5 showing the results of the Tukey HSD test for the effect of interactions between rearing seasons & host plants on cocoon yield of A. mylitta indicated nine homogeneous groups of means that differed significantly from one another.
Tukey HSD test for the effect of rearing seasons on cocoon yield (number) / 300 larvae ofA. mylitta, reared on different host plants
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Stars in each column represent a homogenous group; df- Degree of freedom
Tukey HSD test for the effect of host plants on cocoon yield (number) / 300 larvae ofA. mylitta, reared on different host plants
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Stars in each column represent a homogenous group; df- Degree of freedom
Tukey HSD test for the effect of interactions between rearing seasons & host plants on cocoon yield (number) / 300 larvae ofA. mylitta
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Stars in each column represent a homogenous group; df- Degree of freedom
Higher cocoon yield is a desirable character; therefore, a higher value of EI is preferable for better economic returns. Table 6 indicates that four forestry host plants viz., T. alata (61.75), T. tomentosa (58.06), T. arjuna (55.90) and L. speciosa (53.36) scored higher indices (EI >50) and therefore, were found superior to T. bellirica (47.55), L. tomentosa (33.82) and T. chebula (39.57). Our results show that for the best cocoon yield of A. mylitta in Uttarakhand, T. alata is the best-suited food plant followed by T. tomentosa, T. arjuna , and L. speciosa .
Evaluation Index for cocoon yield (number) / 300 larvae ofA. mylitta, reared on different host plants
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Evaluation Index for cocoon yield (number) / 300 larvae of A. mylitta, reared on different host plants
Discussion
Cocoon yield in A. mylitta is a complex character that depends on interaction of various contributing traits ( Sinha ., 1995 ). Cocoon crops of A. mylitta depend on developmental vigour of silkworm and rearing season and quality of the host plants ( Venugopal and Krishnaswami, 1987 ). Results of the present study also indicated that cocoon yield of A. mylitta differs significantly between rearing seasons and host plants ( p <0.05).
In present study, higher cocoon yield was found in first rearing season than the second one, which confirms that seasonal variations play a major role in the growth and development of A. mylitta larvae and weight of silk gland that contribute to cocoon yield ( Ueda ., 1969 ; Takeshita ., 1975 ; Mathur and Mathur, 1996 ). Further, in second rearing season, prolonged larval period due to low temperature ( Tamiru ., 2012 ) increases caterpillar’s exposure to natural enemies ( Isenhour ., 1987 ), because larval period is inversely related to temperature and relative humidity ( Tamiru ., 2012 ).
We found that forestry host plants showed significant influence on cocoon yield of A. mylitta . It is found that T. alata fed larvae showed highest cocoon yield, followed by T. tomentosa , T. arjuna and L. speciosa fed larvae. Whereas, L. tomentosa fed larvae showed the lowest cocoon yield, followed by T. chebula . It was also found that cocoon yield of T. tomentosa and T. arjuna fed larvae did not differ significantly with each other. Our results are showing the conformity with the findings of Deka and Kumari (2013) , who had assessed the effect of T. tomentosa, T. arjuna , T. bellirica, T. chebula, L. speciosa and L. parviflora on rearing performance and cocoon characteristics of A. mylitta in the agro-climatic conditions of Ranchi, Jharkhand and reported comparable performance of T. tomentosa and T. arjuna in cocoon productivity.
Success of any insect depends mainly upon an optimal diet in both quantity and quality ( Hassell and Southwood, 197 8), which provides energy, nutrients, and water to carry out life’s activities ( Slansky, 1993 ). Carbohydrates, proteins, and lipids are the main sources of energy at the time of larval-larval, larval-pupal, pupaladult transformation ( Krishnaswami, 1978 ; Thangamani and Vivekanandan, 1984 ). Higher availability of these nutritional components has been reported in T. alata , T. tomentosa , T arjuna and L. speciosa than T. bellirica , T. chebula and L. tomentosa ( Agrawal ., 1980 ; Sinha and Jolly, 1971 ; NISCAIR, 1976 ).
Reports are available on moisture contents of the host plant leaves, which have a positive correlation with cocoon productivity of A. mylitta ( Krishnaswami, 1978 ; Thangamani and Vivekanandan, 1984 ). High moisture content in host plant’s leaves has favourable effects on the palatability and assimilability of nutrients ( Parpiev, 1968 ). Deka and Kumari (2013) found higher leaf moisture content of 72.07% in T. tomentosa , followed by L. speciosa (71.21%) and T. arjuna (70.36%) and recorded cocoon productivity of 86, 80 and 82 cocoons/DFL, respectively. These results support the present findings. Further, some workers ( Stride and Stratman, 1962 ; David and Gardiner, 1966 ; Jermy ., 1968 ; Fraenkel, 1969 ) have produced experimental evidences in support of the contention that insect becomes “conditioned” to a particular host plant, because food first eaten by a phytophagous insect becomes its subsequent feeding behaviour. In our experimental rearing also, this fact stands true for the larvae of A. mylitta , which adopted L. tomentosa host plants by the first time in Uttarakhand and completed its life cycle.
Conclusion
Our results confirmed that for achieving best cocoons productivity of A. mylitta in tropical forest areas of Uttarakhand, T. alata is the best-suited food plant, followed by T. arjuna, T. tomentosa , and L. speciosa . Accordingly, State Forest Department may initiate systematic plantation of T. alata, T. tomentosa, L. speciosa and T. arjuna through their various afforestation, reforestation and plantation programme to create a new forest insect industry of A. mylitta in Uttarakhand to promote its adoption by tribals and rural communities inhabiting in forest fringe areas to improve their livelihood.
References
Agarwal SC , Jolly MS , Sinha AK 1980 Foliar constituents of secondary food plants of tasar silkworm, Antheraea mylitta Indian Forester 106 (12) 847 - 851
Basu AC 1944 Effect of different foods on the larval development of the moth, Prodeni litura Fb. (Lepidoptera, Noctuidae) Journal of the Bombay Natural History Society 44 (1&2) 275 - 288
Bhatia NK , Yousuf M 2013 Reassuring livelihood functions of the forests to their dependents, Adoption of collaborative forest management system over Joint forest management regime in India Annals of Forest Research 56 (2) 377 - 388
Bhatia NK , Yousuf M 2013 Forest insect industry in collaborative forest management, an overview International Journal of Industrial Entomology 27 (1) 166 - 179
Brues CT 1920 The selection of food plants by insects, with special reference to Lepidoptera larvae American Naturalist 54 313 - 322
Brues CT 1924 The specificity of food plants in the evolution of phytophagous insects American Naturalist 58 127 - 144
2012 Why Sericulture Central Silk Board, Ministry of Textiles, Government of India Bangalore, India
David WAL , Gardiner BOC 1966 The effect of sinigrin on the feeding of Pieris brassicae L. larvae transferred from various diets Entomologia Experimentalis et Applicata 9 (1) 95 - 98
De Foliart GR 1992 Insect as human food Crop Protection 11 (5) 395 - 399
Deka M , Kumari M 2013 Comparative study of the effect of different food plant species on cocoon crop performance of tropical tasar silkworm (Antheraea mylitta Drury) International Journal of Research in Chemistry and Environment 3 (1) 99 - 104
Dubey AK , Mishra US , Dixit SA 1981 Effect of host plant on the developmental stages of gram pod borer, Heliothis armigera (Hubner) Indian Journal of Entomology 29 48 - 57
Fraenkel G 1969 Evaluation of our thoughts on secondary plant substances Entomologia Experimentalis et Applicata 12 (5) 473 - 486
Hassell MP , Southwood TRE 1978 Foraging strategies of insects Annual Review of Ecology and Systematics 9 75 - 98
Isenhour DJ , Wiseman BR , Layton RC 1987 Enhanced predation by Orius insidiosus (Hemiptera, Anthocoridae) on larvae of Heliothis zea and Spodoptera frugiperda (Lepidoptera, Noctuidae) caused by prey feeding on resistant corn genotypes Environmental Entomology 18 418 - 422
Jermy T , Hanson FE , Dethier VG 1968 Induction of specific food preferences in Lepidopterous larvae Entomologia Experimentalis etApplicata 11 211 - 230
Jolly M S , Sen S K , Ahsan M M 1974 Tasar Culture 33 - 45
Jolly MS , Sen SK , Sonwalkar TN , Prasad GK 1979 FAO Manuals on Sericulture, Vol (4) Non - mulberry Silks Food and Agriculture Organization of the United Nations Rome Biochemistry of tasar food plants 84 - 85
Krishnaswami S 1978 New technology of silkworm rearing Indian silk 16 (12) 7 - 15
Mano Y , Nirmal Kumar S , Basavaraja HK , Mal Reddy N. , Dutta RK 1993 A new method to select promising silkworm breeds/combinations Indian Silk 31 (10) 53 -
Mano Y , Nirmal Kumar S , Basavaraja HK , Mal Reddy N , Dutta RK , Reddy GS 1998 Silkworm Breeding Oxford IBH Publication Company Private Limited New Delhi Combined trait selection for silk yield improvement in Bombyx mori Linn 278 - 284
Mathur JP , Mathur AP 1996 Seasonal effect on survival and cocoon production of pure and hybrid races of B. mori L. under sub humid south plan zones of Rajasthan Journal of Parasitology and Applied animal Biology 5 (2) 75 - 79
Mathur SK , Singh BMK , Sinha AK , Sinha BRRP 1998 Integrated package for rearing of A. mylitta D Indian Silk 37 (2) 15 - 18
Muafor FJ , Levang P , Angwafo TE , Gall LE 2012 Making a living with forest insect, bettles as an income source in Southwest Camroon International Forestry Review 14 (3) 314 - 325
Nayak BK , Guru BC 1998 Studies on cocoon biometry of the bivoltine tasar silkmoth Antheraea mylitta Drury (Lepidoptera, Saturniidae) reared at Bangiriposi Bulletin of Indian Academy of Sericulture 2 (1) 31 - 34
1976 The Wealth of India - An Encyclopedia of India’s Raw Material Resources Vol. X Council of Scientific and Industrial Research -National Institute of Science Communication and Information Resources (CSIR-NISCAIR) New Delhi 157 - 177
Pandey ND , Yadava DR , Teotia TPS 1968 Effect of different food plants on larval and post larval development on Diacrisia obliqua Walk Indian Journal of Entomology 30 (3) 229 - 234
Parpiev A 1968 Water metabolism in silkworm fed with a different mulberry strains changing diet Shelk 39 15 - 17
Singh HN 1975 Larval development of Prodenia litura F. in relation to certain cultivated plants India Journal of Entomology 37 (1) 1 - 6
Sinha AK , Jolly MS 1971 Foliar constituents of the food plants of tasar silk worm Antheraea mylitta D The Indian Forester 97 (5) 261 - 263
Sinha AK , Sengupta AK , Sharma KK , Sinha BRRP , Sinha SS , Manna G.K. , Roy S.C. 1995 Perspective in Cytology and Genetics Hindasia Publishers Delhi, India Yield components and their implication to better genotype of Antheraea mylitta Drury (Lepidoptera, Saturniidae) 617 - 626
Slansky F 1980 Effect of food utilization on food consumption and reproductive allocation by adult milkweed bugs Journal of Insect Physiology 26 79 - 84
Srivastava BK 1959 Growth potential of Laphyqma exiqua in relation to certain food plants Madras Agriculture Journal 46 (7) 255 - 259
Stride GO , Stratman R 1962 The host plant relationship of an Australian swallow stain, Papilio aeges and its significance in the evolution of its host plant selection Proceedings of Linnean Society of New South Wales 87 69 - 78
Takeshita H. , Suto M , Kumata K , Sakate S , Matsumara M , Shigematsu H 1975 Biological characteristic of factors concerning silk formation in the silkworm Bombyx mori Linn Journal of Sericulture Society of Japan 44 183 - 189
Tamiru A , Getu E , Jembere B , Bruce T 2012 Effect of temperature and relative humidity on the development and fecundity of Chilo partellus (Swinhoe) (Lepidoptera, Crambidae) Bulletin of Entomological Research 102 9 - 15
Thangamani R , Vivekanandan M 1984 Physiological studies and leaf analysis in the evaluation of best mulberry varieties Sericologia 24 (3) 317 - 324
Thangavelu K 2004 Host plant wealth of Vanya Silks in the Himalayan states and strategies for its utilization Directorate of Sericulture, Government of Uttarakhand Proceedings of National Workshop on Potential and Strategies for Sustainable Development of Vanya silk in the Himalayan States Dehradun, India 8-9 November 2004 1 - 8
Thobbi VV 1961 Growth potential of Prodenia litura F;relation to certain food plants at Surat Indian Journal of Entomology 23 (4) 262 - 264
Ueda S , Kimura R. , Suzuki K 1969 Studies on the growth of the silkworm B. mori II. The influence of rearing condition upon the larval growth, productivity of silk substance and eggs and boil off loss in cocoon shell Bulletin of Sericultural Experiment Station Japan 23 255 - 293
Venugopal P , Krishnaswami S 1987 Adoptability of silkworm, Bombyx mori Linn. to tropical condition Indian Journal of Sericulture 26 (2) 63 - 71
2011 Uttarakhand State Perspective and Strategic Plan 2009-2027 Water Management Directorate (WMD), Government of Uttarakhand Dehradun 188 -