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Zephyra compacta is a geophyte plant endemic to Chile with the potential to be used as an ornamental crop. Its natural habitat is the coastal plains of the Atacama Desert, with a climate described as coastal desert with abundant cloudiness. This work analyzes the germination of Z. compacta seeds at 10, 15, 20, and 25 °C. Seeds were collected in 2011 and stored for 2 years and 4 months at 5 °C, until sowing. A mathematical model was used for germination analysis, p = A{1 − exp[−k(t − t0)]}, where p is the germination percentage at a certain time t, A is the final germination percentage, t0 is the estimated time of germination of the first seed, and k is the measure of the spread of the time to germination. Furthermore, the rate of germination of the median seed to germinate (1/tA/2) was included. The germination curves showed a coefficient of determination (R2) between 0.86 and 0.99. The results show that temperature range for germination is from 10 to 20 °C, where A is over 90%. In this range, other evaluated parameters (t0, k, and 1/tA/2) show no significant difference, with the exception of k at 15 °C. At this temperature, germination is obtained in a shorter period of time and could be considered as the optimal temperature within the range. Finally, 25 °C is a supraoptimal temperature, where the value of A decreased to 30%.

Leucocoryne is a Chilean endemic genus from the Amaryllidaceae family. It is an emerging crop with some registered varieties, currently oriented to a niche ornamental market. In the present work, seed germination in Leucocoryne dimorphopetala, Leucocoryne coquimbensis, Leucocoryne purpurea, Leucocoryne aff. vittata, Leucocoryne aff. violacescens, and Leucocoryne ixioides for seeds stored for 4 months and in L. purpurea, Leucocoryne vittata, L. aff. vittata, and L. ixioides for seeds stored for up to 16 months was analyzed at 10, 15, 20, or 25 °C. Germination data were analyzed by the previously developed time-germination model p = A{1 − exp[−k(t − t0)]}. Each germination curve had a coefficient of determination (R2) higher than 0.89, except when there was lack of germination. Results show that higher germination was better achieved at lower (10 or 15 °C) rather than at the higher temperatures (20 or 25 °C). When comparing germination results at temperatures of 10 and 15 with results at 20 °C, germination decreased by at least 30% and became near zero at 25 °C in seed stored for 4 months. Similarly when seeds were stored for 16 months, germination decreased by ≈20% at 20 °C, and again was near zero for germination at 25 °C. These germination habits of Leucocoryne are interpreted as an adaptive strategy to its natural habitats. In addition, L. dimorphopetala presents a type of dormancy and other species (L. purpurea, L. ixioides, and L. aff. vittata) may be sensitive to after-ripening changes during storage.

The Chilean endemic genus Conanthera is comprised of five species of herbaceous cormous geophytes. They have ornamental value due to their bell-shaped flowers, which are blue, violet or white. Previous germination studies of Conanthera campanulata and Conanthera trimaculata were carried out at 22 °C, and manual mechanical scarification improved germination. Based on these results, it was suggested that physical dormancy is present in the non-scarified seeds. However, an improvement in germination after scarification is not enough evidence to conclude that the seed is non-permeable to water and thus has physical dormancy. The objective of the present study was to assess the testa water permeability via an imbibition test and to identify the optimum germination temperature in C. campanulata and C. trimaculata. Using 6-mo-old seeds, data from the imbibition tests showed that neither the seeds of C. campanulata nor C. trimaculata have physical dormancy. In the germination experiments, the temperature range for achieving high germination percentages was 10 to 15 °C, where germination reached 90% in less than 28 d. Temperature of 20 °C can be considered supra-optimal, while 5 and 25 °C inhibited germination. Manual mechanical scarification did not affect germination results at the range of 10 to 15 °C. However, at the supra-optimal temperature of 20 °C manual mechanical scarification increased germination, although levels were never higher than 25%.

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