Healthy rice plants in Telangana, India
Rice is the most important food crop of the developing world and the staple food for more than half of the world's population.
Unlike the other two major food crops wheat and maize 80% of the world’s rice growers are smallholder farmers who grow rice as their major food safety net.
90% of the world’s rice is grown in Asia but its growth is not limited to Asia. Rice is cultivated on every continent except Antartica. It can grow in diverse soils and climates – from the high mountains of the Himalaya to the tropic Mekong Delta to the semi-arid desert of West Africa.
In sub-Saharan Africa, rice is the fastest growing staple food. Actually, Africa does not produce enough rice to satisfy the demand and needs to import rice at high economic costs. In 2008, rice import amounted to an estimated $3.6 billion for sub-Saharan Africa. To close this rice production gap, rice yields need to increase.
Bacterial blight - caused by the bacterium Xanthomonas oryzae pv. oryzae (Xoo) - ranks among the biggest constraints for rice production. The disease causes 20-50% yield losses; in extreme up to 70% losses for rice growers.
Typical bacterial blight symptoms include leaf blight, pale yellow leaves and wilting (named "kresek" symptom). Kresek is the most devastating manifestations of the pathogen and is most commonly observed at the seedling stage. Both leaf blight and kresek are the primary effects of the disease while a "pale-yellow" leaf is a secondary effect, appearing on newly emerging leaves of plants recovering from blight or kresek syndrome.
In the US, fear of the rice bacterial blight is so big that the Xoo bacterium is classified as a select agent with potential for bioterrorism. Click here to learn how we can use our molecular understanding of the the bacterial blight infection to engineer resistance against bacterial blight.