Reproductive outputs of two sandalwood landraces with different genetic base and clonality levels in Gunung Sewu, Indonesia

Based on the genetic base and clonality level, sandalwood (Santalum album) formed two types of landraces along with the Gunung Sewu Global Geopark Network in the southern part of Java islands, Indonesia. These two types are represented by Bejiharjo (which has a low genetic base and high clonality) and Bleberan (which has a high genetic base and low clonality) landraces. This study aimed to observe the quality of sandalwood seeds collected from the two landraces to determine the qualified seeds. We collected and tested all produced seeds of fruiting parent trees from August 2019 to March 2020. The physical and physiological quality tests included counting the number of seeds, measuring the seed size, and testing the viability of seeds. The Bleberan landrace produced 9161 seeds with 22.06 of seed viability. Meanwhile, the Bejiharjo produced only 158 seeds, of which all failed to germinate. Lower genetic base and higher clonality increased the inbred progenies, led to inbreeding depression, and decreased seed production and viability. Therefore, the qualified seed from the Bleberan landraces is worth considering to provide future genetic materials.