Abstract
Reproductive traits of a lignified annual plant, Blepharis sindica were studied in relation to the formation of an 'aerial seed pool' on dead plants in an arid grassland in the Thar Desert of northwestern India. The dead plants remained standing on the soil surface and retained fruits for more than one year. Aerial seed pools developed about 6 cm above the ground. There were no seed pools on or below the ground surface. Only 5.7% of seeds died on dead plants because of insect predation or fungi infection during one year. Seed release was cued by rainfall, and a fraction of seeds on the aerial seed pools was released in each rainfall event. After 13 rainfall events during the monsoon season, 25% of seeds was still retained on the plants. Seed predation on the ground surface was intensive; all cones placed on the soil surface were removed within four days, and 97% of fruits were removed within 10 days. Fifty percent of seeds germinated within 3.5 h, and there were no differences in viability and time required for germination between first year seeds and older seeds. The results indicate that the aerial seed-holding on dead plants is an available way to avoid seed predation in harsh desert environments where seed predation is intense and favorable periods for growth are temporally limited and unpredictable.
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References
Baker, H. G. 1972. Seed weight in relation to environmental conditions in California. Ecology 53: 997-1010.
Bhandari, M. M. 1990. Flora of The Indian Desert. MPS Repros, Jodhpur, India.
Bond, W. J. 1984. Fire survival of Cape Proteaceae - influence of fire season and seed predators. Vegetatio 56: 65-74.
Bond, W. J. 1985. Canopy-stored seed reserves (serotiny) in Cape Proteaceae. S. Afr. J. Bot. 51: 181-186.
Borchert, M. I. & Jain, S. K. 1978. The effect of rodent seed predation on four species of California annual grasses. Oecologia 33: 101-113.
Brown, J. S. & Venable, D. L. 1986. Evolutionary ecology of seed bank annuals in temporally varying environments. Am. Nat. 127: 31-47.
Cohen, D. 1966. Optimizing reproduction in a randomly varying environment. J. Theor. Biol. 12: 119-129.
Cowling, R. M. and Lamont, B. B. 1987. Post fire recruitment of four co-occurring Banksiaspecies. J. Appl. Ecol. 24: 645-658.
Ellner, S. & Schmida, A. 1981. Why are adaptations for long-range seed dispersal rare in desert plants? Oecologia 51: 133-144.
Enright, N. J., Lamont, B. B. & Marsula R. 1996. Canopy seed bank dynamics and optimum fire regime for the highly serotinous shrub, Banksia hookeriana.J. Ecol. 84: 9-17.
Fenner, M. 1985. Seed Ecology. Chapman and Hall, London.
Freas, K. E. & Kemp, P. R. 1983. Some relationships between environmental reliability and seed dormancy in desert annual plants. J. Ecol. 71: 211-217.
Günster, A. 1994a. Seed band dynamics-longevity, viability and predation of seeds of serotinous plants in the central Namib Desert. J. Arid Environ. 28: 195-205.
Günster, A. 1994b. Variability in life history parameters of four serotinous plants in the Namib Desert. Vegetatio 114: 149-160.
Gutterman, Y. 1972. Delayed seed dispersal and rapid germination as survival mechanisms of the desert plant Blepharis persica(Burm.) Kuntze. Oecologia 10: 145-149.
Gutterman, Y. 1991. Strategies of Seed Dispersal and Germination in Plants Inhabiting Deserts. Bot. Rev. 60: 277-317.
Gutterman, Y. 1993. Seed Germination in Desert Plants. SpringerVerlag, Berlin.
Gutterman, Y. & Ginott, S. 1994. Long-term protected' seed bank' in dry inflorescences of Asteriscus pygmaeus; achene dispersal mechanism and germination. J. Arid Environ. 26: 149-163.
Gutterman, Y., Witztum A., & Evenari, M. 1967. Seed dispersal and germination in Blepharis persica(Burm.) Kuntze. Israel J. Bot. 16: 213-234.
Harper, J. L. 1977. Population Biology of Plants. Academic Press, New York.
Inouye, R. S., Byers, G. S., & Brown, J. H. 1980. Effects of predation and competition on survivorship, fecundity, and community structure of desert annuals. Ecology 61: 1344-1351.
Jurado, E. & Westoby, M. 1992a. Germination biology of selected central Australian plants. Aust. J. Ecol. 17: 341-348.
Jurado, E. & Westoby, M. 1992b. Seedling growth in relation to seed size among species of arid Australia. J. Ecol. 80: 407-416.
Kalisz, S. & McPeek, M. A. 1993. Extinction dynamics, population growth and seed banks: An example using an age-structured annual. Oecologia 95: 314-320.
Lamont, B. B., Le Maitre, D. C., Cowling, R. M., & Enlight, N. J. 1991. Canopy Seed Storage in Woody Plants. Bot. Rev. 57: 277-317.
Leishman, M. R. & Westoby, M. 1994. The role of seed size in seedling establishment in dry soil conditions-experimental evidence from semi-arid species. J. Ecol. 82: 249-258.
Morse, D. H. & Schmitt, J. 1985. Propagule size, dispersal ability, and seedling performance in Asclepias syriaca. Oecologia 67: 372-379.
Mares, M. A. & Rosenzweig, M. L. 1978. Granivory in north and south American deserts: rodents, birds, and ants. Ecology 59: 235-241.
Morton, S. R. 1985. Granivory in arid regions: comparison of Australia with North and South America. Ecology 66: 1859-1866.
Pake, C. E. & Venable, D. L. 1996. Seed banks in desert annuals: implications for persistence and coexistence in variable environments. Ecology 77: 1427-1435.
Philippi, T. & Seger, J. 1989. Hedging one's evolutionary bets, revisited. Tr. Ecol. Evol. 4: 41-44.
Reader, R. J. 1993. Control of seedling emergence by ground cover and seed predation in relation to seed size for some old-field species. J. Ecol. 81: 169-175.
Reichman, O. J. 1979. Desert granivore foraging and its impact on seed densities and distributions. Ecology 60: 1085-1092.
Shanker, V. 1983. Depleted vegetation of the desertic habitat: Study on its natural regeneration. CAZRI Monograph 21: 1-30.
Tevis, L., Jr. 1958. Interrelations between the harvester ants Veromessor pergandei(Mayr) and some desert ephemerals. Ecology 39: 695-704.
Venable, D. L. & Levin, D. A. 1985. Ecology of achene dimorphism in Heterotheca latifolia. J. Ecol. 73: 133-145.
Wada, N., Narita, K., Kumar, S., & Furukawa, A. 1995 Impact of overgrazing on seed predation by rodents in the Thar desert, northwestern India. Ecol. Res. 10: 217-221.
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Narita, K., Wada, N. Ecological significance of the aerial seed pool of a desert lignified annual, Blepharis sindica (Acanthaceae). Plant Ecology 135, 177–184 (1998). https://doi.org/10.1023/A:1009713512472
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DOI: https://doi.org/10.1023/A:1009713512472