NEW FUNDS TO COMBAT CASSAVA DISEASE

A cassava is a hardy and very useful crop that does well in droughts and poor soils. It requires little input from farmers and is valuable because every part of the plant can be utilised, from its leaves to its roots. However, Cassava Brown Streak Disease (CBSD) is disrupting cassava production on a massive scale.

CBSD is caused by the Cassava Brown Streak virus which induces a dry rot in the cassava tubers preventing people from eating them. As an important staple food to over 200 million people CBSD is one of the greatest threats to food security in sub-Saharan Africa.

Reacting to this crisis, The Bill & Melinda Gates Foundation have given US$ 2.4 million to a number of agricultural institutes across Africa, including IITA, to further the creation of cassava varieties resistant to the disease.

A cassava infected with CBSD

The four year project aims to identify the DNA markers associated with the resistance genes in different varieties and integrate marker-assisted selection into cassava breeding programs.

Marker-assisted breeding will enable scientists to determine whether or not the desired genes with CBSD resistance have been successfully transferred from the parents to the offspring at the seedling stage by using DNA testing. This will dramatically reduce the time taken to develop improved varieties which currently takes between eight and 12 years.

According to Dr. Morag Ferguson, IITA Plant Molecular Geneticist and the team project leader, breeding for disease-resistant cassava is the most cost-effective and sustainable way to control the devastating effects of the virus.

She says: "The use of molecular markers can reduce this time by allowing selection earlier on in the breeding cycle and by increasing the accuracy of selection. It is like using a magnet in a game of find the needle in the haystack!"

The grant forms part of The Bill & Melinda Gates Foundation’s Agricultural Development Initiative, which is working with a wide range of partners in sub-Saharan Africa and South Asia to provide millions of small farmers with tools and opportunities to boost their yields, increase their incomes and build better lives for themselves and their families.