PLANT CELL BIOTECHNOLOGY AND MOLECULAR BIOLOGY

Rattan is one of the most important non-timber forest products, which has been contributing to poverty reduction in remote areas. However, its production from natural forests has been remarkably reduced in recent decades because of over-exploitation and forest degradation for agricultural land and timber demand. Planting rattans was estimated to increase rapidly in the next decades. Therefore, techniques for successfully growing rattans are becoming urgent needs. This work aimed at evaluating the effects of shading levels (40-43% full sunlight and 50-53%) on survival rate and initial growth of three rattans (Calamus tetradactylus, C. rudentum and C. platyacanthus) in Northwestern Vietnam. The results indicated that shading levels did not significantly affect survival rate, height and number of internodes at 6 months of growth. However, such growths in 50-53% shading level were higher than that in 40-43% shading. Among three study rattans, C. tetradactylus had the highest survival rates (> 95%), the best growths (> 38 cm height and > 6.5 internodes) and the lowest dead causes by insect and fungi (< 2%). While conversely, it was observed in C. rudentum with lowest survival rate (< 84%), the shortest stem (< 30 cm) and the highest dead causes by insect and fungi (up to 10%). It was concluded that secondary natural forests with a shading level of 40-55% should be selected to grow C. tetradactylus, C. rudentum and C. platyacanthus. Pesticides should be applied before growing to the field to reduce dead seedlings caused by locusts.