A comparative study of seed morphology in relation to desiccation tolerance and other physiological responses in 71 Eastern Australian rainforest species. Issue 1 (26th March 2012)

• Record Type: Journal Article
• Authors: HAMILTON, KIM N.; OFFORD, CATHERINE A.; CUNEO, PETER; DESEO, MYRNA A.
• Is Part Of: Plant species biology. Volume 28:Issue 1(2013:Jan.)
• Page Start: 51
• Page End: 62
• Publication Date: 2012-03-26
• Subjects: Plants -- Evolution -- Periodicals; Plants -- Classification -- Periodicals; 581
• DOI: 10.1111/j.1442-1984.2011.00353.x
• Languages: English
• ISSNs: 0913-557X

Abstract

<abstract abstract-type="main" xml:lang="en"> <title>Abstract</title> <p>Seed characteristics were measured in 71 Eastern Australian rainforest species representing 30 families. Sensitivity to desiccation to low moisture contents (< 10%) occurred in 42% of species. We estimate, based on findings from 100 species from this present study and previously published reports, that 49% of Eastern Australian rainforest species have non‐orthodox seeds. Germination level and time to 50% germination were not significantly different between desiccation sensitive (DS) and desiccation tolerant (DT) seeds. The estimation of seed desiccation sensitivity based on predictors is an important tool underpinning <italic>ex situ</italic> conservation efforts. Seed characteristics differed significantly between DS and DT seeds; that is, DS seeds had: (i) larger fruits (19 949 mg <italic>vs</italic> 8322 mg); (ii) larger seeds (1663 mg <italic>vs</italic> 202 mg); (iii) higher seed moisture contents (49.7% <italic>vs</italic> 35.5% fresh weight); (iv) lower oil content (7.3% <italic>vs</italic> 24.8% yield); and (v) less investment in seed coats (0.19 <italic>vs</italic> 0.48 seed coat ratio). Only 25% of DS seeded species had oily seeds compared with 87% of DT seeded species. Most green embryos were DS. Seed coat ratio was the best predictor of seed DS (80% correctly predicted). Seed moisture content at maturity was also related to germination time. Mean seed size was correlated (−0.657, <italic>P</italic> = 0.01) with mean seed oil content in 46 species. Further research on seed storage physiology of possible oily and/or DS seeded species is crucial to ensure future long‐term security of this biodiversity, particularly for species currently threatened <italic>in situ</italic> and/or of socioeconomic importance in Eastern Australian rainforests.</p> </abstract>