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

Abstract

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. In nature, A. mylitta has opted forty-five forest tree species as primary, secondary and tertiary food plants (Srivastav and Thangavelu, 2005) and have built up sixty-four different forms of ecological populations called ecoraces (Rao et al., 2003). The polyphagous nature of the tasar silkworm is a boon for many rural tribal in central The knowledge regarding insect-host plant relationship has highlighted the food preference by insects with regard to its nutritional value. Long back, Hiratsuka (1920) carried out a comprehensive quantitative study on digestion and utilization of Bombyx mori on mulberry leaf. Thereafter, Evans and Goodliffe (1939) worked on utilization of food by insects. Earlier studies on utilization of food by insects were not clearly described because several indices were used to report more or less the same measurement in different names (Hopkins, 1912;Evans and Goodliffe, 1939; Crowell, 1941;Smith, 1959;Mathur, 1967;Saxena, 1969). Study of the effects of host plants on the biology of insects is important in understanding the host suitability under different environmental condition (Xue et al., 2009). First, Thangavelu (1992 emphasised the need for conservation of wild sericigenous insects in Himalayan states of India. He highlighted the importance of systematic research on various aspects of non-mulberry silks, because studies on the host plant interaction of sericigenous insects are necessary for better management and development of the sericulture industry (Sinha et al., 2000). Siddiqui et al. (2006) stressed that conservation of A. mylitta in different pockets of forest under different geographical and climatic area is necessary and some of the commercial ecoraces of A. mylitta viz., Raily, Modal, Bhandara, Sukinda, Daba and Andhra local are being maintained in different forest areas of central India; but it is lacking in Uttarakhand. As suggested by many sericulturists, the specific climatic and geographical pockets...

Host Plant Management Strategies for Quality Tasar Seed Cocoon Production

“…The quality and quantity of tasar host plants is directly correlated to its environment, even micro climate change influence the soil micro flora thereby affecting the mobilization of minerals. The nutritional quality of leaf influences the feeding behavior, growth and finally development of silkworm which later affect the cocoon quality and dfl production (Bhatia andYousuf, 2014 andRam et al, 2016). Prolonged rearing duration due to low nutritive value of foliage has serious implications like predatory pressure, population segregation and occurrence of pests and diseases (Bora andSaikia, 2022 andLokesh et al, 2016).…”

Harvesting Silk Fibers from Plodia interpunctella: Role of Environmental Rearing Conditions in Fiber Production and Properties

“…RGD is present in the protein sequence of silk fibroins produced by Antheraea mylitta; 28 however, Antheraea mylitta is difficult to rear in a laboratory setting with detrimental impacts on silk production with current indoor rearing protocols. 29 Antheraea mylitta has seasonally dependent life cycles that are around 2 months long, where production is impacted by external factors (e.g., climate change 30 ). Current collection methods for Antheraea mylitta include rearing in a forest with human-based collection from the forest, 30,31 meaning that production is outdoors, eliminating a researcher's or company's control over rearing conditions prior to use in manufacturing.…”

“…Antheraea mylitta has seasonally dependent life cycles that are around 2 months long, where production is impacted by external factors (e.g., climate change). Current collection methods for Antheraea mylitta include rearing in a forest with human-based collection from the forest, , meaning that production is outdoors, eliminating a researcher’s or company’s control over rearing conditions prior to use in manufacturing. This is a common challenge for translating alternative silk-producing species to biomedical applications, and while Plodia ’s fibroin proteins do not contain RGD, its standardized indoor rearing parameters warrant further investigation on how its unique sequence in the silk biomaterial space can be leveraged.…”

Temporal variability in foliar protein content and trypsin inhibitory levels in two host trees of tropical Tasar silkworm Antheraea mylitta, Drury

“…This is particularly relevant for tropical Tasar sericulture. Bhatia and Yousuf (2014) and Jena (2016) demonstrated that seasonal availability of diet with balanced levels of nutrients is an important prerequisite for rearing this insect.…”