GROWTH PERFORMANCE OF Azadirachta indica A. Juss PROVENANCES IN THE DRY ZONE OF SRI LANKA

Abstract

Azadirachta indica A. Juss (Neem) is a multipurpose tree whose leaves, fruits, seeds and trunkproduce various products for industrial and domestic uses. Although it has attracted the specialinterest of many researchers and has been popularized among farmers by various institutes, littlehas been done to provide suitable planting materials according to the farmers' requirements.Identification of highly productive individuals is very important to produce suitable plantingmaterials. Provenance testing is the first step in this regard.

Nine introduced and two locally collected A. indica provenances were established at ForestDepartment Research Station, Korakahawewa, Anuradhapura in 1995 to evaluate growthperformances. The growth and development of those provenances were assessed by using nineparameters, namely survival rate, diameter growth at breast height (DBH), height to the firstbranch, bark thickness, bark surface, stem straightness, resistance to shoot borer attack andbranching habit at four years after its establishment Mid ranking of significant growth anddevelopment parameters were used to identify best overall performers.

Results of the study revealed that provenances are varied for growth and developmentparameters. The best DBH and height growth with 100% survival of plants were recorded forprovenance Ban Huaysai Tai from Thailand: Provenance Rajanpur from Pakistan showed thesecond highest DBH and height growth with 100% survival. The second highest rank for stemstraightness was also recorded for Rajanpur provenance. Provenance Rahimyar Khan fromPakistan is highly resistant to shoot borer attack with good ranks for other tested parameters.Overall mid ranking of all provenances for the significant growth and development parametersmeasured showed that provenances of Rahimyar Khan, Rajanpur, (Pakistan), Ban Huaysai Tai(Thailand) and Kataragama (Sri Lanka) were superior to all other tested provenances at the endof four years of growth. Future implications of the results are also discussed in this paper.