Influence of forestry host plants and rearing seasons on silk gland weight of tropical tasar silkworm, Antheraea mylitta (Lepidoptera: Saturniidae) under Doon valley conditions of Uttarakhand in India

Bhatia, Narendra Kumar,Yousuf, Mohd.,Tewary, Pankaj,Sharma, Satya Prakash Korean Society of Sericultural Science 2016 International Journal of Industrial Entomology Vol.32 No.1

Tropical tasar silkworm, Antheraea mylitta is a commercial forest silkworm in India that produces tasar silk, but never experimented in Uttarakhand, a Himalayan state of India. A. mylitta express divergent phenotypic characters under different ecological conditions; so, we studied the effect of seven forest tree species in two rearing seasons on variability in silk gland weight of Daba (bivoltine) ecorace of A. mylitta at Forest Research Institute in Dehra Dun, Uttarakhand during 2012 and 2013. We used two-way completely randomized block factorial design and Post HOC Tukey's HSD test to analyse the collected data and there after carried out multiple regression analysis. Results indicated that silk gland weight differed significantly between rearing seasons (DF=1, F=2333.98, p <0.05), host plants (DF 6, F= 1516.25, p <0.05) and their interactions (DF=6, F=7.10, p <0.05). Higher silk gland weight was found in second rearing season than the first on all the host tree species. Terminalia alata fed A. mylitta larvae showed the highest silk gland weight of 8.03 and 9.47 g in first and second rearing seasons, followed by T. tomentosa (7.19 & 9.01g), T. arjuna (6.8 & 8.08 g) and L. speciosa (6.57 & 7.83 g) fed larvae, respectively. Post HOC Tukey's HSD test indicated that silk gland weight of L. speciosa and T. arjuna fed larvae in both the rearing seasons did not differ significantly. E.I. analysis also confirmed that T. alata, T. tomentosa, T. arjuna and L. speciosa are better in their order of merit than T. bellirica , T. chebula and L. tomentosa. Multiple regression analysis indicates that larval weight gain is a strong predictor (β=1.002, t=346.777, p = <0.05) for the silk gland weight of A. mylitta ; however, larval duration had significant negative regression weight (β=-0.270, t=-8.436, p = <0.05) on mean weight of silk gland.

Effect of rearing season, host plants and their interaction on economical traits of tropical tasar silkworm, Antheraea mylitta Drury- an overview

Bhatia, Narendra Kumar,Yousuf, Mohammad Korean Society of Sericultural Science 2014 International Journal of Industrial Entomology Vol.29 No.1

Tropical tasar silkworm, Antheraea mylitta (Lepidoptera: Saturniidae) is a polyphagous silk producing forest silkworm of commercial importance in India. Forest dependent people rear its larvae on different forestry host plants twice or thrice in a year for small household income. Larvae of A. mylitta feeds on many forest tree species, but always show a great degree of selectivity as a function of its behavioural responses to physical structure and chemical features of the host plants. Cocoon crop of A. mylitta is influenced by heterogeneity of tasar food plants and climatic conditions of the habitat. The role of host plants, temperature, humidity, rainfall, photoperiod and climatic variables on the growth and development of insects have clearly been demonstrated. This article entails an in-depth analysis on ecological and nutritional aspects of A. mylitta, which may provide selective information to researcher and forest managers, who are particularly associated with livelihood improvement of the poor people in forested area through location specific forest insect industry.

Parasitic Behaviour of Xanthopimpla pedator Fabricius (Hymenoptera: Ichneumonidae) on Tropical Tasar Silkworm, Antheraea mylitta Drury (Lepidoptera: Saturniidae) Reared on Seven Forestry Host Plants in Uttarakhand, India

Bhatia, Narendra Kumar,Yousuf, Mohammad Korean Society of Sericultural Science 2013 International Journal of Industrial Entomology Vol.27 No.2

Antheraea mylitta Drury is a commercial silk producing forest insect in India and Xanthopimpla pedator Fabricius is its larval-pupal endoparasitoid, which causes pupal mortality that affects seed production. Effects of host plants, rearing season and their interactions on parasitic behaviour of X. pedator were studied here, as influence of these factors on biological success of X. pedator is not known. Seven forest tree species were tested as food plants for A. mylitta, and rate of pupal parasitization in both the rearing seasons were recorded and analysed. Results showed that rearing season and host plants significantly affected the rate of pupal parasitization in both the sexes. Pupal mortality was found significantly higher (14.52%) in second rearing season than the first (2.89%). Likewise, host plants and rearing seasons significantly affected length, diameter, and shell thickness of cocoons in both sexes. Out of all infested pupae, 85.59% were found male, which indicated that X. pedator chooses male spinning larva of A. mylitta for oviposition, but we could not answer satisfactorily the why and how aspect of this sex specific parasitic behaviour of X. pedator. Multiple regression analysis indicated that length and shell thickness of male cocoons are potential predictors for pupal parasitization rate of X. pedator. Based on highest cocoon productivity and lowest pupal mortality, Terminalia alata, T. tomentosa, and T. arjuna were found to be the most suitable host plants for forest based commercial rearing of A. mylitta in tropical forest areas of Uttarakhand state, where it has never been reared earlier. Sex and season specific interaction of X. pedator with its larval-pupal host, A. mylitta is a novel entomological study to find out explanations for some of the unresolved research questions on parasitic behaviour of X. predator that opens a new area for specialised study on male specific parasitization in Ichneumonidae.

Forest Insect Industry in Collaborative Forest Management: An Overview

Bhatia, Narendra Kumar,Yousuf, Mohammad Korean Society of Sericultural Science 2013 International Journal of Industrial Entomology Vol.27 No.1

In India, forest based insect enterprises has never been linked up with any forest management activity, either as a forest conservation strategy or to reduce the poverty in forested area. This investigation indicated that when forest dependent people are associated with forest insect industry (FII) like forest sericulture, lac culture or apiculture; this income generating activity links livelihood with forest conservation, and generates a viable model of collaborative forest management (CFM). In this model different stakeholders work together as a coherent entity for unified goal of managing the forest for well-being of the poor people in fringe areas. Article summaries and evaluates the prospect of India specific forest insect industry, and discusses how and to what extent integration of FII could be a viable livelihood component in CFM to conserve the forest and insect biodiversity. We analysed a case study on forestbased rearing of tropical tasar silkworm rearing in Central India from CFM perspective. Arguments in this communication are intended to provide forest managers and policy-makers with necessary input to consider location specific FII in CFM mode to provide a continuous source of small income to forest dependent people to ensure long lasting success of their forest management endeavours.

Review : Effect of rearing season, host plants and their interaction on economical traits of tropical tasar silkworm, Antheraea mylitta Drury-an overview

( Narendra Kumar Bhatia ),( Mohammad Yousuf ) 한국잠사학회 2014 International Journal of Industrial Entomology Vol.29 No.1

Tropical tasar silkworm, Antheraea mylitta (Lepidoptera: Saturniidae) is a polyphagous silk producing forest silkworm of commercial importance in India. Forest dependent people rear its larvae on different forestry host plants twice or thrice in a year for small household income. Larvae of A. mylitta feeds on many forest tree species, but always show a great degree of selectivity as a function of its behavioural responses to physical structure and chemical features of the host plants. Cocoon crop of A. mylitta is influenced by heterogeneity of tasar food plants and climatic conditions of the habitat. The role of host plants, temperature, humidity, rainfall, photoperiod and climatic variables on the growth and development of insects have clearly been demonstrated. This article entails an in-depth analysis on ecological and nutritional aspects of A. mylitta, which may provide selective information to researcher and forest managers, who are particularly associated with livelihood improvement of the poor people in forested area through location specific forest insect industry.

Forest Insect Industry in Collaborative Forest Management: An Overview

( Narendra Kumar Bhatia ),( Mohammad Yousuf ) 한국잠사학회 2013 International Journal of Industrial Entomology Vol.27 No.1

In India, forest based insect enterprises has never been linked up with any forest management activity, either as a forest conservation strategy or to reduce the poverty in forested area. This investigation indicated that when forest dependent people are associated with forest insect industry (FII) like forest sericulture, lac culture or apiculture; this income generating activity links livelihood with forest conservation, and generates a viable model of collaborative forest management (CFM). In this model different stakeholders work together as a coherent entity for unified goal of managing the forest for well-being of the poor people in fringe areas. Article summaries and evaluates the prospect of India specific forest insect industry, and discusses how and to what extent integration of FII could be a viable livelihood component in CFM to conserve the forest and insect biodiversity. We analysed a case study on forestbased rearing of tropical tasar silkworm rearing in Central India from CFM perspective. Arguments in this communication are intended to provide forest managers and policy-makers with necessary input to consider location specific FII in CFM mode to provide a continuous source of small income to forest dependent people to ensure long lasting success of their forest management endeavours.

Influence of forestry host plants and rearing seasons on silk gland weight of tropical tasar silkworm, Antheraea mylitta (Lepidoptera: Saturniidae) under Doon valley conditions of Uttarakhand in India

( Narendra Kumar Bhatia ),( Mohd. Yousuf ),( Pankaj Tewary ),( Satya Prakash Sharma ) 한국잠사학회 2016 International Journal of Industrial Entomology Vol.32 No.1

Tropical tasar silkworm, Antheraea mylitta is a commercial forest silkworm in India that produces tasar silk, but never experimented in Uttarakhand, a Himalayan state of India. A. mylitta express divergent phenotypic characters under different ecological conditions; so, we studied the effect of seven forest tree species in two rearing seasons on variability in silk gland weight of Daba (bivoltine) ecorace of A. mylitta at Forest Research Institute in Dehra Dun, Uttarakhand during 2012 and 2013. We used two-way completely randomized block factorial design and Post HOC Tukey’s HSD test to analyse the collected data and there after carried out multiple regression analysis. Results indicated that silk gland weight differed significantly between rearing seasons (DF=1, F=2333.98, p <0.05), host plants (DF 6, F= 1516.25, p <0.05) and their interactions (DF=6, F=7.10, p <0.05). Higher silk gland weight was found in second rearing season than the first on all the host tree species. Terminalia alata fed A. mylitta larvae showed the highest silk gland weight of 8.03 and 9.47 g in first and second rearing seasons, followed by T. tomentosa (7.19 & 9.01g), T. arjuna (6.8 & 8.08 g) and L. speciosa (6.57 & 7.83 g) fed larvae, respectively. Post HOC Tukey’s HSD test indicated that silk gland weight of L. speciosa and T. arjuna fed larvae in both the rearing seasons did not differ significantly. E.I. analysis also confirmed that T. alata, T. tomentosa, T. arjuna and L. speciosa are better in their order of merit than T. bellirica , T. chebula and L. tomentosa. Multiple regression analysis indicates that larval weight gain is a strong predictor (β=1.002, t=346.777, p = <0.05) for the silk gland weight of A. mylitta ; however, larval duration had significant negative regression weight (β=-0.270, t=-8.436, p = <0.05) on mean weight of silk gland.

Yield Gap Analysis of Mulberry Sericulture in Northwest India

Bhatia, Narendra Kumar,Yousuf, Mohammad,Nautiyal, Raman Korean Society of Sericultural Science 2013 International Journal of Industrial Entomology Vol.27 No.1

At the interface of reducing agricultural income and increasing unemployment in agrarian economy of rural India, this article summarizes and evaluates the state of mulberry sericulture in northwest India, which includes Himachal Pradesh, Punjab, Rajasthan, Uttarakhand, and Uttar Pradesh. In $11^{th}$ plan period (2007-2012), there was an addition of 6 196 ha (217.09 %) of mulberry acreage at annual linier growth rate of 33.44%. However, total silk production could increase only by 54.64 MT (78.57%) at annual linier growth rate of 15.59 %, due to 43.93% (10.82 kg/ha) reduction in silk productivity at negative growth rate of -13.46%, annually. And now, average raw silk productivity in north-western states of India remains at 13.81 kg/ha, which is lower by 452.93 % (76.36 kg) in comparison to the national average of 100.90 kg/ha. Paper summaries the reasons for increasing cocoon yield gap at farmer's level and discuss the ways and means to increase raw silk productivity to improve the livelihood delivery of mulberry sericulture in northwest India.

Parasitic Behaviour of Xanthopimpla pedator Fabricius (Hymenoptera: Ichneumonidae) on Tropical Tasar Silkworm, Antheraea mylitta Drury (Lepidoptera: Saturniidae) Reared on Seven Forestry Host Plants in Uttarakhand, India

( Narendra Kumar Bhatia ),( Mohammad Yousuf ) 한국잠사학회 2013 International Journal of Industrial Entomology Vol.27 No.2

Antheraea mylitta Drury is a commercial silk producing forest insect in India and Xanthopimpla pedator Fabricius is its larval-pupal endoparasitoid, which causes pupal mortality that affects seed production. Effects of host plants, rearing season and their interactions on parasitic behaviour of X. pedator were studied here, as influence of these factors on biological success of X. pedator is not known. Seven forest tree species were tested as food plants for A. mylitta, and rate of pupal parasitization in both the rearing seasons were recorded and analysed. Results showed that rearing season and host plants significantly affected the rate of pupal parasitization in both the sexes. Pupal mortality was found significantly higher (14.52%) in second rearing season than the first (2.89%). Likewise, host plants and rearing seasons significantly affected length, diameter, and shell thickness of cocoons in both sexes. Out of all infested pupae, 85.59% were found male, which indicated that X. pedator chooses male spinning larva of A. mylitta for oviposition, but we could not answer satisfactorily the why and how aspect of this sex specific parasitic behaviour of X. pedator. Multiple regression analysis indicated that length and shell thickness of male cocoons are potential predictors for pupal parasitization rate of X. pedator. Based on highest cocoon productivity and lowest pupal mortality, Terminalia alata, T. tomentosa, and T. arjuna were found to be the most suitable host plants for forest based commercial rearing of A. mylitta in tropical forest areas of Uttarakhand state, where it has never been reared earlier. Sex and season specific interaction of X. pedator with its larval-pupal host, A. mylitta is a novel entomological study to find out explanations for some of the unresolved research questions on parasitic behaviour of X. predator that opens a new area for specialised study on male specific parasitization in Ichneumonidae.