Research on the propagation of Dacrycarpus imbricatus (Blume) de Laub from seeds

Abstract

Dacrycarpus imbricatus (Blume) de Laub is a valuable native tree species for timber with high economic value. The present study was conducted to evaluate the seed characteristics, exam the effect of growth regulator GA 3 on the germination of seeds, and the effect of fertilizer methods and shade ratio on the growth of seedlings at the nursery stage. The results showed that Dacrycarpus imbricatus (Blume) de Laub seed colors are between yellow-orange and red when they are ripe. There were about 8,811 seeds per kg with an average seed length was 0.65 ± 0.03 cm and the average seed width reached 0.54 ± 0.03 cm. The percentage of water content in the seeds was 43.14%. Seeds were treated with GA3 at the different concentrations range of 100 ppm to 400 ppm. The results also indicated the germination rate of the seeds was over 80% while the control is 61.67%. The suitable fertilizing NPK (30-10-10+TE) method is 10 days/time with the concentration of 10g/l, corresponding to an average height of seedlings being 20.95 cm and average stem diameter reaching 3.09 mm. After 10 months of follow-up in the experiment, the seedlings had significant growth in both height and root diameter. The best shading was 75% in the first 4 months and from the 4th month onwards, 50% light shading gave the best growth in height and root diameter at 24.79 cm and 3.64 mm, respectively