Pre-Sowing Treatments on Seeds of Forest Tree Species to Overcome the Germination Problems

Abstract

Production of the quality planting material has got more emphasis under sub-mission on agroforestry (SMAF) with aiming to increase tree cover outside the forest area. Establishment of the tree species depends on the quality of the planting material, available soil, water for irrigation and the adopted protection measures. Most of the tree species get problem with germination of seed due to external and internal factors and causes seed dormancy. Different kind of pre-sowing treatments were tested and applied for the different kind of tree species by researchers of the forestry. Scarification (mechanical, acid), water soaking (hot/cold), the application of chemicals and plant growth regulators, or alternate wetting and drying prior to sowing effectively break seed dormancy and improve seed germination for producing required quality planting material. Auxins (IAA, IBA, 2-4D, 4-CPA), Gibberellic acid (GA3), Cytokinins (Kinetin, Zeatin, Benzyl adenine), Ethylene (Etheral) and Abscisic acid (Dormins, Phaseic Acid) are plant growth regulators also used in different concentrations for improving tree seed germination.