Biotechnological Approaches for the Diagnosis of Silkworm Diseases

Incidences of silkworm diseases are one of the major stresses, which make considerable economic crop losses and reduce profitability every year in India. Silkworms are highly prone to several innumerable virulent pathogens including bacteria, viruses, fungi, and parasitic microbes like microsporidia. There are four major diseases of silkworms, viz., grasserie, flacherie, muscardine, and pebrine. All these diseases are infectious and spread rapidly to the healthy worms. The infection in the early stage (first to third stage) always leads to the outbreak of the diseases at the later stages. Several reports are available on crop loss due to silkworm diseases, which varies from 15 to 40% in India. For better management of silkworm diseases, early diagnosis of pathogens plays a vital role in reducing the spread of pathogens. In general, silkworm diseases are always diagnosed through visible symptoms and microscopic examinations, which is a labor-intensive, less efficient, less sensitive, and time-consuming process. Several advanced molecular techniques and approaches were already employed for rapid and accurate diagnosis of numerous silkworm pathogens. These techniques are based on nucleic acid hybridization, polymerase chain reaction, serological techniques (antibody based techniques), and biosensors. However, these advanced diagnostic techniques are not feasible at all time as they have their own limitations in many aspects like involvement of high initial cost, requirement of infrastructure, sensitivity, accuracy, and reliability. There is always a demand for the simple, rapid, accurate, and cost-effective techniques for early diagnosis of silkworm diseases. In this chapter, information regarding different advanced techniques employed for silkworm disease diagnosis along with their advantages and limitations will be provided.