Bacterial wilt of ginger (Zingiber officinale Rosc.) incited by Ralstonia pseudosolanacearum-A review based on pathogen diversity, diagnostics and management

Ginger (Zingiber officinale Rosc.) is one of the most important spice crops cultivated in India and several other countries such as China, Nepal, Indonesia and Nigeria. Bacterial wilt of ginger, referred to as ginger blast or Mahali/ green wilt caused by Ralstonia pseudosolanacearum Safni et al. 2014 (formerly Ralstonia solanacearum), is the most destructive pathogen of ginger reported from all the ginger growing countries. This bacterium has a wide host range and is notoriously known for its aggressiveness and ability to survive in soil for many years. Without understanding the symptomatology, epidemiology or genetic diversity of the pathogen, it is impossible to develop suitable diagnostics or management strategies against this pathogen. Common strategies employed for bacterial wilt management met with limited success and still it remains as an enigma. This literature review therefore mainly focused on the symptomatology, diversity and diagnosis of the pathogen and also on the management strategies adopted to mitigate the problem.