Seed germination responses of four Limonium species to temperature

Seed germination responses to temperature in one indigenous species, Limonium aureum, and three introduced species, L. bicolor, L. gmelinii and L. otolepis were studied under controlled conditions in the laboratory. The temperature rang of seed maximum germination rate for L. aureum (95% to 97%) was 10 to 20 ℃, and for L. bicolor (95% to 100%), L. gmelinii (over 98%) and L. otolepis (97% to 99%) were 15 to 25 ℃, 20 to 35 ℃ and 20 to 30 ℃, respectively. The temperature rang for seed maximum germination potentiality of L. aureum was 15 to 20 ℃, for these of L. bicolor, L. gmelini, and L. otolepis were 15 to 20 ℃, 20 to 35 ℃ and 25 to 30 ℃. The temperature rang of seed maximum germination index for L. aureum was 15 to 20 ℃, but for L. bicolor was 20 to 25 ℃, for L. gmelinii was 25 to 30 ℃ and for L. otolepis was 20 ℃. The maximum value of germination index appeared in different temperatures, where for L. aureum, L. bicolor and L. otolepis appeared at 20 ℃ with the germination indexes of 36.26, 37.26 and 24.34, respectively. However, the maximum value of germination index for L. gmelinii presented to 30 ℃ with the index of 33.12. The temperature rang of seedling length maximum value for L. aureum was 15 to 20 ℃, for L. bicolor was 20 to 25 ℃, for L. gmelinii was 25 to 30 ℃ and for L. otolepis was 20 to 25 ℃. In general, the optimum germination temperature range for four Limonium were 15 to 20 ℃, 20 to 25 ℃, 25 to 30 ℃ and 20 to 25 ℃, respectively.