The analyses of the data collected on six occasions in between 1977 and 1990 from the permanent sample plots in the Sundarbans of Bangladesh arc presented in the present paper. The diameter at breast height (dbh) increment for the two important species — sundri (Jleritiera fomes Buch. Ham.), and gewa (Excoecaria agallocha Linn.) were estimated separately for all the site qualitics/hcight classes and salinity zones. The mean dbh increments per year ranged from 0.062 cm to 0.151 cm for sundri and 0.049 cm to 0.189 cm for gewa. There were only a small number of trees for passur (Xylocarpus mekongensis Pierre), keora (Sonneratia apetala Buch. -Ham), baen (Avicennia officinalis Linn.) and kankra (Bruguiera spp.). Therefore, the mean annual dbh increments were estimated for all the site qualities and salinity zones together. The mean dbh increments for passur, kcora, baen and kankra were 0.206 cm, 0.192 cm, 0.219 cm and 0.178 cm respectively. The increment rate was higher at higher site qualities and lower salinity zones. But it does not depend on the forest composition. Top dying sundri trees showed lower dbh increment rate.

The rate of ingrowth for sundri was 15 trees per hectare per year, while the natural death and removals were 27 trees per hectare per year. The corresponding data for gewa were 22 and 8.1 respectively. The observation suggests that proportion of gewa is increasing and sundri is decreasing. Kcora is being eliminated naturally without natural regcncaration in the plots.

During 1981-83, 12 to 16 years old jack fruit (Artocarpus heterophyllus L.) trees grown in Chittagong University campus were severely affected with brown leaf spots. Nigrospora sphaerica (Sacc.) Mason and Pestalotiopsis Versicolor (Sperg.) Steyaert were found to be associated with the disease (Herb. IMI No. 266275) and the pathogens are a new record for the plant. As these fungi have not been reported on jack fruit tree in Bangladesh, a study was made to determine their pathogenicity with jack fruit plant. The disease samples were collected and the symptoms of the disease were recorded carefully. The most characteristic symptoms of the disease appeared in the months of December, January and February. At first brown yellow coloured spots of 0.5-10mm. appeared on infected leaf and then the spots gradually coalesced and became larger to attain a size upto 11.0 cm.