Utilization of water-absorbent in vegetative propagation of Pai Tong Khaew (Dendrocalamus asper Backer.)

Utilization of water-absorbent, AGSORB-P (crosslinked polyacrylamide), for vegetative propagation of Pai Tong Khaew was studied at Tongpapoom district, Kanchanaburi province during July 1992 to December 1994. Five experiments were carried out during that period. Experiment 1 was investigated on physical characteristics of soil, soil mixed with manure at the ratio of 5:1 and soil mixed with water-absorbent at 3 rates namely: 0.2, 0.5 and 1.0 percent dry weight. It was found that soil mixed with water-absorbent showed better physical properties than soil alone and soil mixed with manure in either field capacity, available water capacity, infiltration and bulk density. Experiment 2, direct planting of branch cuttings in the field, was done during rainy season to study the efficacy of water-absorbent on growth and drought survival of branch cuttings. The same experimental treatments as experiment 1 were used. The result showed that there was no significant differences among treatments. Branch cuttings in all treatments appeared satisfactory growth and drought survival similarly. Experiment 3, direct planting of branch cuttings in the field, was done during dry season to study the efficacy of water-absorbent on growth and drought survival of branch cuttings. The same experimental treatments as experiment 1 and 2 were used. Statistical data collection was unable to collect due to the branch cuttings in all treatments were died after planting for 6 months. Experiment 4 was done during dry season to study the efficacy of water-absorbent on growth and drought survival of branch cuttings that were grown in opaque plastic bags and water application were made only once a week. The same experimental treatments as experiment 1, 2 and 3 were used. It was revealed that branch cuttings in soil mixed with 0.2 percent water-absorbent showed the best result. Experiment 5 was done during dry season to study the efficacy of water-absorbent on growth and drought survival of branch cuttings that were grown in transparent plastic bags with and without holes. Coconut coir mixed with water-absorbent at rate 0.0, 0.2, 0.5 and 1.0 percent dry weight was used as rooting media. Only one water application was done after growing, then the bags were sealed. It was revealed that growth and drought survival of branch cuttings were related to the increasing amount of water-absorbent in coconut coir. Bags without holes showed the tendency of growth and drought survival better than bags with surrounding holes.