Terap (Artocarpus elasticus Reinw. ex Blume) is a native Indonesian plant that can be a functional and medicinal food source. The conservation of terap has focused on implementing the field gene bank at botanical gardens. These methods presented risks, such as aging, pest and disease susceptibility, and weather-related threats; thus, diversifying conservation strategies, notably through seed banking, is imperative to mitigate these challenges. This study aimed to determine the physiological maturity level and critical moisture content crucial for effective terap seed banking. When harvested, physiological maturity determination used three fruit colors: green, orange, and orange-fall fruits. The critical moisture content identification of seeds had seeds dried for 0, 2, 4, 6, and 8 days in a room at 18 °C ± 2 °C and 55%–65% relative humidity, as predicted by regression analysis. The results indicated optimal quality and viability from physiologically mature orange fruits harvested 100–120 days after anthesis, with 35.31 g 100-seed dry weight and 75%–80% germination percentage. The germination evaluation revealed that the first count was 35 days after sowing, and the final count was 50 days after sowing. The seeds had 0.63% per 24 h germination rate, 64% germination uniformity, and more than 82% emergence ability. The critical moisture content was 36.93%, suggesting terap seeds are recalcitrant; hence, seed banking requires storage conditions to be moist. In addition, storing seeds can also proceed by in vitro techniques, using tissue culture and cryopreservation.
Germination, moisture content, recalcitrant, seed banking, seed characteristic
Terap fruits colored orange were physiologically mature fruits with physiologically mature seeds. The critical moisture content was 36.93%, suggesting terap seeds are recalcitrant. These findings will benefit terap germplasm conservation. Proper germplasm conservation will maintain the genetic diversity of terap and make it easier for breeders to manage the germplasms for their future work.