Central Tuber Crops Research Institute, Thiruvananthapuram-695017, India.
Abstracts of the papers presented at the International Conference of Indian Virological Society on “Emerging and Re-emerging viral Diseases of the Tropics and Subtropics” at Indian Agricultural Research Institute, New Delhi, India, December 11–14, 2007.
Tropical tuber crops, the most useful food crops after cereals, provide food to millions of people living in rural tropics and subtropics. They include cassava, sweet potato, yams, edible aroids etc. These crops are subjected to attack by more than 20 viruses or virus-like diseases on a global basis. However in India only six have been found to be widely prevalent. They cause heavy losses both in yield and quality of the produce. Yield reduction due to cassava mosaic disease is reported to vary from 20 to 80% depending on the varieties and stage of infection. Since all these crops are propagated vegetatively, the virus diseases also spread very fast. The rate of spread and degeneration of cassava due to CMD varied among varieties and even in field resistance varieties, entire plant population degenerated within three to four years. Based on the findings on disease incidence, spread, their effect on growth and production, integrated management practices have been proposed against these diseases with emphasis on the health status of the planting material and phytosanitary measures. Virus free plants obtained through meristem tip culture have out grown and out yielded normal plants and that the increase in growth and yield over normal plants varied among varieties. Effective certification programme including grow-out test, serological and nucleic acid based assays and frequent field inspection is discussed.
