TY - JOUR
T1 - Seed germination in Chrysophyllum sp. nov., a large-seeded rainforest species in north Queensland
T2 - Effects of seed size., litter depth and seed position
AU - Green, Peter T.
PY - 1999/12
Y1 - 1999/12
N2 - Leaf litter affects seed germination in many ways and past studies have shown greater impacts on relatively small seeds, both within and among species. In this shade-house experiment I examined the impact of forest litter on seed germination in Chrysophyllum sp. nov. (Sapotaceae), a large-seeded (2.4 g) rainforest tree from north Queensland. Seed mass varies more than 30-fold in this species, making it useful for studying the role of litter as a possible selective pressure in the evolution of seed size in large-seeded species. Seeds of varying size (small, medium, large) were sown in planting boxes containing one of three litter levels (low, medium, high) and placed either below or on top of the litter. Seed size and litter biomass had no significant impact on the number of germinating seeds or the time to germination but seeds placed below the litter germinated around twice as frequently, and 20% sooner, than seeds placed on top of the litter. There were no significant interactions between any of the three factors. This shade-house experiment suggests that leaf litter is not an important selective pressure in the evolution of seed size in this species. However, if litter disturbance under field conditions differentially affects the probability of seed germination in relation to seed size and/or litter biomass, then litter could still act as a selective pressure in the evolution of seed size in Chrysophyllum and other large-seeded species.
AB - Leaf litter affects seed germination in many ways and past studies have shown greater impacts on relatively small seeds, both within and among species. In this shade-house experiment I examined the impact of forest litter on seed germination in Chrysophyllum sp. nov. (Sapotaceae), a large-seeded (2.4 g) rainforest tree from north Queensland. Seed mass varies more than 30-fold in this species, making it useful for studying the role of litter as a possible selective pressure in the evolution of seed size in large-seeded species. Seeds of varying size (small, medium, large) were sown in planting boxes containing one of three litter levels (low, medium, high) and placed either below or on top of the litter. Seed size and litter biomass had no significant impact on the number of germinating seeds or the time to germination but seeds placed below the litter germinated around twice as frequently, and 20% sooner, than seeds placed on top of the litter. There were no significant interactions between any of the three factors. This shade-house experiment suggests that leaf litter is not an important selective pressure in the evolution of seed size in this species. However, if litter disturbance under field conditions differentially affects the probability of seed germination in relation to seed size and/or litter biomass, then litter could still act as a selective pressure in the evolution of seed size in Chrysophyllum and other large-seeded species.
KW - Chrysophyllum sp. nov.
KW - Large-seeded species
KW - Leaf litter
KW - Rainforest
KW - Seed germination
KW - Seed size
UR - http://www.scopus.com/inward/record.url?scp=17944367546&partnerID=8YFLogxK
U2 - 10.1046/j.1442-9993.1999.00994.x
DO - 10.1046/j.1442-9993.1999.00994.x
M3 - Article
SN - 1442-9985
VL - 24
SP - 608
EP - 613
JO - Austral Ecology
JF - Austral Ecology
IS - 6
ER -