Pengaruh Pematahan Dormansi Terhadap Kemampuan Perkecambahan Benih Angsana (Pterocarpus Indicus Will)

Abstract

INTRODUCTION. So far, Seedling production of Angsana (Pterocarpus indicus Will) is done by stem cutting. Seedling propagation by seeds is not done widely, as well as its silvicultural system is still not known yet. Seed germination percentage is affected strongly by seed quality (physic, genetic and physiology). The main problem of seed germination of Angsana seeds is seed coat dormancy; therefore it is important to study the breaking dormancy techniques of Angsana seeds. The aim of this research was to study the effects of breaking dormancy treatment to the germination capacity of Angsana seeds. MATERIAL AND METHOD. This research was done from 30 June to 28 Agust 2008 at Green House, the Laboratory of Silviculture, Faculty of Forestry, Bogor Agricultural University. The material and equipment used in this experiment consisted of Angsana seeds, hot water, H2SO4, KNO3, water from fermented bamboo shoots (Gigantochloa apus Kurz), rice hull charcoal, subsoil, germination boxes, soaking bath, watering equipment, analytical balance, stationary, ruler, calliper, and digital camera. The research procedures consisted of several steps; those were seed extraction and selection, seed water content measurement, breaking dormancy treatments, germination, maintenance, observation, and data collection and analysis. The experimental design in this research was completely randomised design which consisted of 6 soaking treatments, those were soaking in hot water for 30 minutes followed by soaking in cold water for 12 hours (B0), soaking in the fermented bamboo shoot liquid for 12 hours (B1), soaking in H2SO4 1% for 10 minutes (B2), soaking in H2SO4 1 % for 15 minutes (B3), soaking in KNO3 1 % for 12 hours (B4) and soaking in KNO3 for 24 hours (B5). Each experiment unit was replicated in three replicates. The observed parameters consisted of germination capacity, germination value, speed of germination, germination rate, germination time at 80%, high and diameter of transplanted seedlings. The collected data was analysed using F test followed by Duncan Multiple Range Test (DMRT). RESULTS AND CONCLUSSION. Angsana seeds had embryonic and seed coat dormancies. Based the results of F test and Duncan test showed that soaking in H2SO4 1% for 10 minutes and in KNO3 1 % for 24 hours could break those dormancies. It was indicated by it high germination percentage (100 %), and other values such as germination value (1,13% to 1.05% normal germinants/day2), germination speed (1, 41 %/day), germination rate (19,32 – 18,59 day), germination time at 80% (25 day), seedlings height (1,53 cm) , and diameter growth (1,06 mm to 1,1 mm) respectively. Key word: Angsana, Pterocarpus indicus Will, Dormancy.