S. Ahmad
Not Available
C.A. Call
Not Available
E.W. Schupp
Not Available
ABSTRACT
Experiments were conducted in a representative Cymbopogon-Chrysopogon grassland in upland Balochistan to determine how seed (spikelet) attributes and seed (spikelet) dispersal mechanisms influence the regeneration of Cymbopogon jwarancusa and Chrysopogon aucheri. Cymbopogon jwarancusa had more filled and viable caryopses than Chrysopogon aucheri. Spikelets of both species have similar morphological features. Spikelet dispersal occurs primarily by wind over a 2 to 3-week period in late-June/early-July. Chrysopogon aucheri has one dispersal unit, a triplet spikelet. Cymbopogon jwarancusa has four different dispersal units: a paired spikelet, a partial raceme, an entire raceme, and a partial inflorescence (two racemes). Mean dispersal distances of spikelets from the perimeter of the basal crown of Cymbopogon jwarancusa and Chrysopogon aucheri plants were 94 and 79 cm, respectively. Spikelets were distributed in all directions around parent plants; however, the mean angle of dispersal for both species was toward the northeast, according to the prevailing wind direction. Spikelets of Cymbopogon jwarancusa and Chrysopogon aucheri moved mean distances of 26 and 32 cm, respectively, from all locations on the ground surface before becoming trapped in a microhabitat. Gravel interspaces and areas beneath plant canopies were the most common microhabitats, and captured the majority of spikelets of both species.
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How to cite this article
S. Ahmad, C.A. Call and E.W. Schupp, 2000. Regeneration Ecology of Chrysopogon Aucheri and Cymbopogon Jwarancusa in
Upland Balochistan: I. Morphology, Viability and Movement of Seeds (Spikelets) . Pakistan Journal of Biological Sciences, 3: 1583-1587.
DOI: 10.3923/pjbs.2000.1583.1587
URL: https://scialert.net/abstract/?doi=pjbs.2000.1583.1587
DOI: 10.3923/pjbs.2000.1583.1587
URL: https://scialert.net/abstract/?doi=pjbs.2000.1583.1587
REFERENCES
- Aguiar, M.R. and O.E. Sala, 1997. Seed distribution constrains the dynamics of the Patagonian steppe. Ecology, 78: 93-100.
CrossRefDirect Link - Carey, P.D. and A.R. Watkinson, 1993. The dispersal and fates of seeds of the winter annual grass Vulpia ciliate. J. Ecol., 81: 759-767.
CrossRefDirect Link - Chambers, J.C., J.A. MacMahon and J.H. Haefner, 1991. Seed entrapment in alpine ecosystems: Effects of soil particle size and diaspore morphology. Ecology, 72: 1668-1677.
CrossRefDirect Link - Chambers, J.C. and J.A. Mcmahon, 1994. A day in the life of a seed; movements and fates of seeds and their implications for natural and managed systems. Ann. Rev. Ecol. Syst., 25: 263-292.
Direct Link - Ernst, W.H.O., E.M. Veenendaal and M.M. Kebakile, 1992. Possibilities for dispersal in annual and perennial grasses in a savanna in Botswana. Vegetatio, 102: 1-11.
CrossRefDirect Link - Peart, M.H., 1979. Experiments on the biological significance of the morphology of seed-dispersal units in grasses. J. Ecol., 67: 843-863.
CrossRefDirect Link - Rabinowitz, D. and J.K. Rapp, 1981. Dispersal abilities of seven sparse and common grasses from a Missouri prairie. Am. J. Bot., 68: 616-624.
Direct Link - Russell, S.K. and E.W. Schupp, 1998. Effects of microhabitat patchiness on patterns of seed dispersal and seed predation of Cercocarpus ledifolius (Rosaceae). Oikos, 81: 434-443.
CrossRefDirect Link - Schott, G.W., 1995. A seed trap for monitoring the seed rain in terrestrial communities. Can. J. Bot., 73: 794-796.
CrossRefDirect Link