Determining the moisture content of Acacia seeds
Geoffrey E. Burrows A *A
Abstract
In a recent paper in Southern Forests, Jaganathan and co-workers indicated that the low constant-temperature drying method (LCTDM) (103°C for 17 h) is satisfactory for determining moisture content (MC) in seeds with physical dormancy (PY). Would this recommendation apply to Acacia, a large genus (1000+ species) with a seed coat so strong that seeds in the soil can maintain high viability for many decades? MC was assessed, using the LCTDM, in six Australian Acacia species by comparing intact seeds with those cut in half. Halved seeds of all species lost moisture rapidly and their mass had largely stabilised after about 2–3 h. Intact seeds had a wide variation in moisture-loss patterns. In some species, the testa was morphologically unchanged after 24 h at 103°C and this was associated with a relatively slow moisture loss. In other species, the testa had completely shattered after 8 h, leading to a rapid moisture loss. If the LCTDM is used to determine MC in Acacia species, it is advisable to employ a technique that substantially disrupts the testa.
Keywords: Acacia, lens, macrosclereid, moisture content, physical dormancy, seed coat, testa, viability.
References
Burrows GE, Virgona JM, Heady RD (2009) Effect of boiling water, seed coat structure and provenance on the germination of Acacia melanoxylon seeds. Australian Journal of Botany 57(2), 139-147.
| Crossref | Google Scholar |
Burrows GE, Alden R, Robinson WA (2018) The lens in focus – lens structure in seeds of 51 Australian Acacia species and its implications for imbibition and germination. Australian Journal of Botany 66, 398-413.
| Crossref | Google Scholar |
Burrows GE, Alden R, Robinson WA (2019) Markedly different patterns of imbibition in seeds of 48 Acacia species. Seed Science Research 29(4), 270-282.
| Crossref | Google Scholar |
Cavanagh AK (1980) A review of some aspects of the germination of acacias. Proceedings of the Royal Society of Victoria 91, 161-180.
| Google Scholar |
Duivenvoorden E, Wagner B, Nitschke CR, Kasel S (2024) Short-interval, high-severity wildfires cause declines in soil seed bank diversity in montane forests of south-eastern Australia. Forest Ecology and Management 553, 121627.
| Crossref | Google Scholar |
Hay FR, Rezaei S, Wolkis D, McGill C (2023) Determination and control of seed moisture. Seed Science and Technology 51(2), 267-285.
| Crossref | Google Scholar |
Jaganathan GK, Li J, Liu B (2022) Low constant temperature drying can be a satisfactory method to determine the moisture content of impermeable seed coated species. Southern Forests 84, 325-327.
| Crossref | Google Scholar |
Singh A, Nitschke CR, Hui FKC, Baker P, Kasel S (2023) Soil seed banks provide a storage effect in post-logging regrowth forests of southeastern Australia. Forest Ecology and Management 548, 121389.
| Crossref | Google Scholar |
Taylor GB (1987) Determination of seed moisture content in small-seeded pasture legumes. Australian Journal of Experimental Agriculture 27, 377-380.
| Crossref | Google Scholar |