Case Study  Blight of sesame (Alternaria sesami)

Trial Field – (FUNAAB) August 2016 – todate,
Crop Sesamum indicum (sesame)
Biopesticide –ARATI Biopecticides
Lead Investigator: Prof. Victor Olowe
Federal University of Agriculture, Abeokuta (FUNAAB)
Department of Plant Physiology and Crop Protection
Mobile: +234 803 3928 111

Sesamum indicum L

 Sesame grown with ARATI Biopesticide, FUNNAB, Abeokuta, Oct., 2016 and pictures by Prof. Victor Olowe.

Figure  1. Blight of sesame pathology world distribution map

Blight of sesame (Alternaria sesami)


Blight of sesame crop. The causal organism. Alternaria sesame. Symptoms – The pathogen attacks all parts of the plant at all stages – Small, dark brown water soaked,

List of symptoms/signs

Fruit  –  lesions: black or brown

Fruit  –  lesions: on pods

Leaves  –  abnormal leaf fall

Leaves  –  necrotic areas

Stems  –  discoloration of bark



Brown to black, round to irregular and often zonate lesions measuring up to 1 cm diam. are produced on the leaves and in severe attacks the leaves dry out and fall off . Stem lesions are either in the form of dark brown spots or streaks. Dark brown, circular lesions are produced on the capsules   which can cause the capsule to drop. The most visible symptoms are the leaf spots which are dark, irregular patches mostly on the edges and tips of the leaves, but the stem rots can be more significant note that can cause seed rot, pre- and post-emergence losses as well as stem rot and leaf spots.


Although considered an important fungal disease of sesame, there is little information about actual economic impact of A. sesami. Kumar and Mishra (1992) state that most of the common diseases of sesame cause yield losses of 20-40%. This yield loss is caused by the premature defoliation of the plants leading to smaller capsules and loss of capsules due to infection.

Prevention and control – Application of ARATI Biopesticide

Application rate: ratio 1:4 Litres   ARATI Biopesticide®