Dalbergia sissoo is an important multipurpose tree species in Bangladesh, India, Nepal, Pakistan and many other countries. Generally, the plantations have a narrow gene base and the source of the seed source/planting material is unknown. The tree is variously grown by government organisations, communities, individual fanners and private landowners, and generally management appears to be inadequate or non-existent. The tree is mostly grown in single stand species by individual fanners to provide ready cash at time of harvest, starting from 20 years onwards. However, with the increased incidence of die-back, farmers are being discouraged from planting and/or replanting and land use may consequently be altered.
The cause of die-back may be multi-faceted and the primary causes are as yet to be confirmed. Common with all countries is the increased incidence of symptoms occurring with increasing clay content of the soils and water logging, both of which are known to impede the normal growth of the tree and to increase stress. Highest incidence was recorded in trees grown on the margins of agriculture land, particularly paddy fields.
Possible pathogens associated with the die-back included a wide range of fungi, but particularly the Fusarium and Ganoderma spp. These were strongly implicated, but the pathogenicity tests have not been completed to confirm it. A complex of insect species have been associated with the later symptoms of the disease, but these are likely to be secondary agents.
- World Bank
- JBIC (Japan Bank of International Co-operation)
Whereas the participants of the Sub-regional Seminar recognise that die-back of Dalbergia sissoo has occurred and is further spreading in all the countries of the sub-region with related socio-ecological and economic losses;
Whereas the causes (both biotic and abiotic stresses) and effects of the die-back problem are unsolved; the participants have agreed on the following:
Whereas further resources are required to analyse and resolve the sissoo die-back problem, each focal institution/person will seed respective Government and donor support for the same;
In order that this problem of sissoo die-back is pursued in a timely fashion, the Department of Forest Research and Survey, Ministry of Forests and Soil
Conservation, Nepal, has been unanimously selected to act as Regional Co-ordinator for the network to be established and implemented.
We the participants hereby declare our agreement to accept the Kathmandu Resolution and the recommendations resulting from the sub-regional workshop.