Germination of Seeds of Various Herbaceous Species under Leaf Canopy

Species Interactions in a Successional Grassland. III. Effects of Canopy Gaps, Gopher Mounds and Grazing on Colonization

“…This method is appropriate for characterizing the seed bank community and its potential contribution to the vegetative community (Major & Pyott 1966). However, the actual contribution of the seed bank to recruitment in any one year will be much less than the total number of viable seeds in the soil, because recruitment from the seed bank depends on a complex of environmental factors and the requirements of species for germination and early survival (Silvertown 1980;Thompson & Grime 1983;Gorski, Gorska & Norwicki 1977;Slade & Causton 1979).…”

Germination Biology and the Ecology of Annual Plants

“…This result occurs because delaying germination does not increase the probability of a seed's germinating in an empty microsite and so cannot increase the finite rate of increase (R). In fact, there is a cost in forming a seed bank that results Gorski (1975), King (1975), Gorski et al (1977), andRees (1989). from the death of seeds before germination.…”

“…However, experimental work has demonstrated that the probability of a seed's germinating depends on the presence of established plants (Gorski 1975;King 1975;Gorski et al 1977;Silvertown 1980;Rice 1985;Farmer and Spence 1987;Benech Arnold et al 1988;Van Tooren and Pons 1988). The main result from this broad body of experimental work is that the presence of established plants inhibits seed germination; this may occur through changes in the red-far red ratio of the incident radiation, the range of temperature fluctuations, or a reduction in soil nitrogen levels.…”

“…There is extensive literature describing the germination responses of seeds to changes in temperature (Popay and Roberts 1970a, 19706;Baskin and Baskin 1972;Mekenian and Willemsen 1975), the range of temperature fluctuations (Cohen 1958;Hussey 1958;Edwards 1968;Thompson et al 1977;Rice 1985), light intensity (Kinzel 1926;Ratcliffe 1961;Wesson andWareing 1969a, 1969b), light spectral composition (Gorski 1975;King 1975;Gorski et al 1977;Silvertown 1980), and the concentrations of various chemicals (Kidd 1914;Kidd and West 1917;Edwards 1968;Popay and Roberts 1970a, 19706). Many of these responses can be interpreted as ways of preventing germination in a hostile environment (Baskin andBaskin 1971, 1974;Fenner 1985).…”

Primary Seed Dormancy in Diffuse and Spotted Knapweed

“…Light quality plays an important regulatory role in the germination of many weedy members of the Asteraceae Wareing 196'7,1968 Gorski 1975;Gorski et al 1977Gorski et al , 1978Bostock 1978;Silvertown 1980). The germination of some species of Centaurea (C. repens, C. solstitialis) appears to be stimulated by white light (Maguire and Overland 1959), while germination of others is inhibited by light rich in far-red wavelengths lC.…”