Sisal Bole Rot: An Important but Neglected Disease

Abstract

Sisal ( Agave sisalana ) is one of the main sources of hard natural fibre and raw materials for the industry, medicine and handicrafts. Sisal yields a coarse and strong fibre that is increasingly being used in composite materials for automobiles, furniture, construction and plastic and paper products. Extracts of sisal contain substances with anti-inflammatory, antimicrobial and anthelmintic activities. Sisal is adapted to warm environments with low rainfall and is an excellent option for cultivation in semiarid conditions, where other crops cannot be grown. The world’s largest sisal producers are Brazil, Tanzania, China, Kenya and Madagascar. Sisal is a labour-intensive crop with great socio-economical importance as it is cultivated in poor areas employing familiar labour. Sisal bole rot is the main disease of sisal, responsible for substantial losses in producing countries. The disease is caused by certain species of the genus Aspergillus , especially the ones belonging in the section Nigri . The main symptoms are yellowing of the aerial parts and the red-coloured rot of the bole, which causes the plant to die. In this review we are going to address the taxonomy of the causal agents, disease diagnosis and epidemiology and disease management, with emphasis on biological control.