Seribiotechnology

India - Way Down the Silk Route
J. Nagaraju, CDFD, Hyderabad (jnagaraju@cdfd.org.in)

India - Way Down the Silk Route

As a major silk-producing country India is home to all the four varieties of natural silks: mulberry, tasar, eri and muga. Each of these silk types is obtained from an unique silkworm species that feeds on one or more specific host plants. However, over 90% of the production constitutes mulberry silk secreted by Bombyx mori that feeds on mulberry (Morus alba) leaves. Though it earned $ 632 million from exports of silk goods, the country is yet to tap the huge international market for handloom products with classic Indian designs.

Even with the successfu introduction of hybrid mulberry silkworm strains and adoption of modern practices, growth in Indian sericulture is facing stagnation as the gap between genetic and realized potentials of the silkworm hybrids is still quite large. Virus infections alone lead to a loss of almost 40% of the silkworm cocoon crop annually. Indian scientists are now using biotechnological tools to ameliorate the production and quality scenario, improve international competitiveness and enable the industry rise to its full potential. Department of Biotechnology (DBT), Govt. of India is spearheading this effort backed by the Central Silk Board and other R&D institutions. Recent endeavors and achievements of Indian researchers in the field of seribiotechnology have placed the country on a very solid footing in this area.


Scientists at Centre for DNA Fingerprinting and Diagnostics (CDFD) at Hyderabad have been quietly bringing about a seribiotech transformation by intelligently blending fundamental and applied research. The notable achievements are (i) deciphering the evolution of silkmoth and dissection of molecular differences between diapausing and non-diapausing silkworm strains, (ii) discovery of insect-specific anti-bacterial proteins and understanding insect immune system, (iii) development of RNA-interference based transgenic silkworm lines resistant to viral menace, (iv) genomic and population genetic analysis of non-mulberry silkmoths to bring their production to commercial scale, (v) development and application of microsatellite markers for

Drought and Salinity Tolerant Mulberry Transgenic Produced
  • Total area under mulberry cultivation for sericulture in the country is
    about 1,79,065 ha. About 45 to 50% area is prone to abiotic stress
    (drought, alkalinity and salinity) conditions
  • Nearly 48% of Indian cultivars of mulberry fall under rainfed, water
    stress conditions.
  • In order to develop suitable mulberry varieties tolerant to drought
    and salinity the DBT launched a program at University of Delhi
    South Campus (UDSC), New Delhi
  • At UDSC, mulberry transgenics with late-embryogenesis-abundant
    (LEA) group of proteins from Hordeum vulgare (HVA-1gene) have
    been developed for drought and salinity tolerance, and
    characterized by PCR and Southern analysis
  • Physiological analysis using membrane stability index, proline
    content, phytosynthesis yield and water-use efficiency indicated
    that transgenics were tolerant towards simulated drought and
    salinity conditions.
  • Limited field trials of mulberry transgenics are being initiated in
    collaboration with Central Sericulture Research & Training Institute,
    Mysore
    Paramjit Khurana, Delhi University South Campus
    (paramjitkhurana@hotmail.com)
    and Mohd. Aslam, DBT (aslam.dbt@nic.in)
    Silkworm as Bioreactor
    SPECIAL SUPPLEMENT

    BOSTONMay 6-9, 2007
    SPECIAL SUPPLEMENT

identification of productive silkworm hybrids in combination with conventional breeding, (vi) generating microsatellite based linkage maps, and (vii)deciphering silkmoth sex-determination pathway with the aim to develop genetic sexing strains in Lepidoptera.


Although the focus of seribiotech development is to generate products to empower farming population engaged in sericulture, the process has also created a robust and competitive infrastructure to carry out world-class seribiotech research. It is only natural that India is now emerging as the new frontier in seribiotechnology .

Silkworm Genome Programme

  • As part of the International Consortium on Lepidopteran Genomics, India successfully undertook construction of high-density linkage map of silkworm (Bombyx mori) and isolation and characterization of 36,400 ESTs from muga and tasar silkworms completed
  • Microsatellite markers for tasar and muga silkworms developed which are used to studying population structure and genetic polymorphism

Silkworm as Bioreactor

  • Expression of veterinary viral antigens (Petit de pet Ruminant Virus and Rinderpest Virus) achieved on infected silkworm larvae using Bm NPV cell-surface
  • Work on immune response and challenge tests of PPRV antigens carried out in collaboration with Indian Veterinary Research Institute, Mukteswar

    Mohd. Aslam, DBT (aslam.dbt@nic.in)