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Seeds have been reported to have a combination of physical and physiological dormancy. However, this study revealed that H. dulcis seeds only have physical dormancy. The water absorption of the seeds after different periods of sulfuric acid scarification was measured, and the water gap through which water was absorbed after scarification treatment was specified. Cold stratification treatment and gibberellic acid treatment were performed after sulfuric acid scarification to determine whether H. dulcis seeds had physiological dormancy. H. dulcis seeds could absorb water completely when scarified for more than 60 min, and water was absorbed only through the hilar fissure near the micropyle, indicating that H. dulcis seeds have physical dormancy. However, there was no synergistic effect on the final seed germination percentage after the cold stratification or gibberellic acid treatments, and germination was delayed under cold temperature conditions. Thus, it was concluded that H. dulcis seeds have no physiological dormancy but only physical dormancy. This study not only clarifies the kind of dormancy in H. dulcis seeds but also provides a method to expedite seed germination without a long cold stratification treatment period of 2 or 3 months.

Early results from a field test of Maesopsis eminii are reported from a progeny test of 100 open-pollinated families of Indonesian seed sources (west Java). Seedling height and diameter at root collar (DRC) were measured in the family tests at 0, 10, and 15 months of age. Age 0 means the measurement just before the planting of the trial. The averages of seedling height and DRC at age 15 months were 134.4 cm and 1.86 cm. Family survival rates were, on average, 65.6% and 62.8% at age 10 and 15 months, respectively. Family genetic variance and replication variance at age 15 months were higher than those at age 10 months. Seedling height was positively correlated with DRC growth and statistically significant at the same ages. The coefficients of genetic variation for seedling height and DRC were ranged from 0.01 to 12.69 and from 1.97 to 13.70, respectively. Heritability estimates obtained were 0.44, 0.04, 0.01, and 0.31, 0.01, and 0.02 for seedling height and DRC at age 0, 10, and 15 months, respectively. Family averages of the 10 best and the 10 poorest families for each trait indicated that there were large differences of seedling height and DRC growth among individual families and between ages. Genetic gain for DRC was expected to be substantial and higher than that for seedling height growth at age 15 months. Those results suggested that growth improvement through the superior family selection of M. eminii could be possible.