A comparative study on seed physiology and germination requirements for 15 species of Eucalyptus

Abstract

Seed physiology of 15 Eucalyptus species of interest for cut foliage plantations was unknown and therefore evaluated. The viability and vigour of seeds and germination potential of 15 Eucalyptus species was determined by using a tetrazolium (TZ) staining test, and the results were compared to a germination test. In a separate experiment, seeds of each lot were subjected to either 0 or 4-week cold stratification at 4 ± 1 °C to investigate their potential stratification requirement. After stratification, seeds were then allowed to germinate at 22 ± 1 °C with 16 h lighting per day for 36 days. Seed viability and vigour were checked by evaluating % root, cotyledon and first true leaves emergence, and the speed of emergence, in the germination test. The germination percentages varied with the species. Seed stratification with the interaction of seed species lots significantly affected both viability and vigour. The seed viability of the different species ranged from 9 to 100% and 2 to 100%, for the TZ test and germination test, respectively, with a high correlation (R2 = 0.89) between the two. Physiology tests revealed that cold stratification of seed was not required for the 15 species to maximise their germination potential and growth in Irish and British climate.

Eucalyptus Species Selection for Superior Adaptability to Indoor-Outdoor Environments in South Korea

“…3). The maximum germination studied in Irish and British climates was rapidly reached by 3 to 10 DAS for 15 Eucalyptus species collected from alpine forests in Australia, mostly due to the suitable growing conditions at these locations although this metric varied significantly for each species (Afroze et al, 2021). Germination at 0-7 DAS was not significantly different among the species at p < 0.05.…”