Handling a pest, gingerly

scientists at the Indian Institute of Spices Research (iisr) in Kozhikode have found how bacterial wilt attacks ginger (Zingiber officinale), an important cash crop. Caused by a family of pathogens called Ralstonia solanacearum, the disease spreads quickly and can cause total crop loss. It is one of the major causes of ginger crop damage.

India is the largest producer of ginger in the world, accounting for 70 per cent of the global output. Almost 180,000 tonnes of ginger is grown annually, mostly by small farmers in Kerala, Karnataka, the seven north-eastern states and certain pockets of Maharashtra, Tamil Nadu and Andhra Pradesh. The spice is exported to more than 50 countries.

iisr scientists found R solanacearum colonises vascular cells (that transport water and minerals) where it multiplies and blocks supply of water and nutrients to the part of the plant above the ground. The plant dies ultimately.

R solanacearum is a large family, sub-divided into five classes or biovars. Two of these