Knowledge for a sustainable world

The main cotton growing area in Tanzania has recently been affected by what appears to be a new disease, afflicting most of the crop in that area.

Temporarily named 'Premature Defoliation Syndrome' (PDS), the disease causes leaf distortion, where the leaves become red in colour and are prematurely shed. As these symptoms occur at the important boll forming stage of growth, PDS can cause a 100% loss of marketable yield.

At present it is not clear if PDS is a disease or a nutrient disorder, but already it is affecting about one third of country's main cotton producing area, the Western Cotton Growing Area (WCGA) which borders on Lake Victoria and the symptoms appear to be spreading.

Dr Rory Hillocks of NRI is working with the Tanzania Gatsby Trust (TGT) as a consultant to support efforts to understand this possibly new problem.

Cotton is one of Tanzania's most important exports and reputedly 14 million people, 40% of the workforce, derive at least part of their income from cotton growing, marketing and processing. The crop is the main source of cash income for some 300,000 smallholders.

Because of its importance as a source of income for rural households and its contribution to national foreign currency earnings, the Tanzanian Government wishes to see an expansion in cotton production. The TGT, in partnership with the Tanzania Cotton Board, is supporting cotton production with a programme that includes seed multiplication and research, conservation agriculture, and contract farming.

Dr Hillocks is providing technical support to the Tanzanian Cotton Scientists at the Lake Zone Agricultural Research & Development Institute, which supports cotton production in WCGA (where he worked as a Cotton Pathologist from 1976-1981).

The first visit to Tanzania took place in January 2013, for a planning meeting with cotton stakeholders to design the research required to determine the cause, and to develop management options, for PDS.

A second visit is planned for April 2013 when symptoms of PDS can be seen in the field. A survey has been organised to determine the extent of the problem and to establish if PDS is spreading. Further research is planned to determine if the cause is pathogenic or nutritive. 


The Tanzania Gatsby Trust (TGT) is a charitable trust that supports Small and Medium Enterprises (SMEs) to carry out productive and profitable enterprises. Its mission is to harness, channel and unleash human energy to build social, financial and physical capital through entrepreneurship development.