Application of molecular and immuno-diagnostic tools for detection, surveillance and quarantine regulation of Karnal bunt (Tilletia indica) of wheat

Abstract

Disease diagnostics and pathogen detection, a primary component of any crop management programme, is also helpful in monitoring sanitary and phyto-sanitary measures to seed quality. Molecular diagnostics based on immunological and DNA techniques can provide an efficient way for disease surveillance and disease forecasting. Karnal bunt (KB) of wheat has become a major disease of economic importance and an important issue in the international wheat trade. Due to its seed borne, soil borne and air borne nature, KB can be diagnosed in three pathogenic forms of pathogens viz. teliospores, sporidial and mycelial forms which occur in infectious or proliferative entities at different stages of the disease cycle. Suitable sampling and extraction procedures can improve the detection limits of modern molecular diagnostic methods used to test KB. For the extraction of teliospores from both infected and infested seeds, highly efficacious detergent washing techniques have been developed and extracted pathogenic entities were diagnosed by involving several species of specific primers and immuno-chemical reagents. Nucleic acid and antibody based techniques have been developed for the detection of KB pathogen in different forms. These techniques can also be successfully employed for differential diagnosis, disease surveillance of seed borne pathogens of quarantine importance and determination of teliospore load in wheat seeds. These tests can also be designed to assist in the trade of wheat, development of disease forecasting models and molecular and immuno-pathotyping of Tilletia indica isolates collected from different agro-climatic regions. Moreover, these formats could also be employed for molecular characterization of disease determinants and in comprehending their role in molecular basis of host-pathogen interaction. The present paper highlights the use of the principle of molecular diagnostics in exerting disease surveillance and quality assurances of seeds.

Generation of diagnostic anti-teliospore antibodies for development of specific immunodiagnostic format for detection of Karnal bunt (Tilletia indica) of wheat

“…For successful management of KB, there is a strong need towards developing rapid and specific immunodiagnostic test procedure to check its further spread to disease-free areas through the use of disease-free seeds (Kumar, Singh, Kumar, & Garg, 2008). Further, the sensitivity and specificity of any immunological procedure are solely dictated by the quality of the immunological reagents employed for the development of an immunodiagnostic assay system.…”

Bacterial and Fungal Pathogen Synergetics after Co-infection in the Wheat (Triticum aestivum L.)

“…Amongst these, kernal blunt is the major disease of wheat and caused by the fungus,Tilletia indica (Syn Nevovosia indica). It is the limiting factor in increasing wheat yield [16,17,18,19]. It affects mainly common wheat, durum wheat, triticale and other related species.…”

Fungicidal Management of Associated Mycoflora With Stored Seeds of Wheat and Chickpea

“…Loose smut (Ustilagonuda tritici), karnal bunt (Tillettiainidica), head blight or scab (Fusarium spp. ), tundo or ear cockle (Clavibacter tritici and Anguina tritici) are major seed borne diseases of wheat crop that reduces the crop yield and grain quality (Kumar et al, 2008). Major diseases of wheat are transmitted by fungal infected seeds.…”