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Seed dormancy and germination in Rottboellia exaltata

Published online by Cambridge University Press:  27 March 2009

P. E. L. Thomas  and
J. C. S. Allision
P. E. L. Thomas
Affiliation:
Henderson Research Station, Private Bag 222 A, Salisbury, Rhodesia
J. C. S. Allision
Affiliation:
Department of Agriculture, University of Rhodesia, Salisbury, Rhodesia
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Summary

Eight laboratory and three field experiments were made on seed of Rottboellia exaltata, a grass weed of maize.

Seed stored dry, indoors or outside, either on the soil surface or buried, was unable to germinate for 5–6 months after being shed. Its ability to germinate then increased rapidly, reaching 50–70% by 8–9 months, and, indoors, continued to increase slowly to reach 80% by about ayear after being shed. Periodic wetting hastened the increase in ability to germinate of seed kept indoors or on the soil surface, but slowed down that of buried seed. When germination was tested with husks removed the ability of the caryopses to germinate began increasing soon after seed was shed, reaching 60% after 3 months and, later, up to 85–95% in different experiments. Dehusking was only effective if the inner bracts as well as the outer husks were removed, but pricking a hole through the husk and inner bracts had an effect similar to removing them. Germination decreased when in-husk seed was immersed in water before being incubated, whether this was done in air or oxygen, or in light or light/darkness, and increased again when seed was dried or its husks pierced before incubation. Wetting and drying in light, but not in darkness, increased germination of in-husk seed, and constant high temperature enhanced the increase.

When seed was buried in soil at a range of depths between 2·5 and 30 cm, the more deeply situated seed remained viable for longer than that near the surface, but there was little viable seed at any depth after 4 years. Many seedlings emerged in the first two rainy seasons after shedding of seed was prevented in an infested field which was ploughed each dry season, but by the third season the number of seedlings had greatly decreased and in the fifth season no seedlings emerged. Most of the seedlings emerging in maize fields came from seeds situated near the surface of the soil.

Type
Research Article
Information
The Journal of Agricultural Science , Volume 85 , Issue 1 , August 1975 , pp. 129 - 134
Copyright
Copyright © Cambridge University Press 1975

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References

REFERENCES

Fernandez, D. B. (1963). Studies on Motiboellia exaitata L.f. I. Biology; and II. Control. Papers presented at the Philippine Sugar Technologists Convention, August 1963. Mimeographed.Google Scholar
Holm, R. E. (1972). Volatile metabolites controlling germination in buried weed seed. Plant Physiology 50, 293–97.CrossRefGoogle Scholar
Holm, L. R. & Herberger, J. (1970). Weeds of tropical crops. Proceedings of the Tenth British Weed Control Conference, pp. 1132–49.Google Scholar
Ivens, G. W. (1968). East African Weeds and their Control. Nairobi: Oxford University Press.Google Scholar
Koller, D. (1972). Environmental control of seed germination. In Seed Biology, vol. II (ed. Kozlowski, T. T.). New York: Academic Press.Google Scholar
Major, W. & Roberts, E. H. (1968). Dormancy in cereal seeds. I. The effects of oxygen and respiratory inhibitors. Journal of Experimental Botany 19, 77–89.CrossRefGoogle Scholar
Millhollon, R. W. (1965). Growth characteristics and control of Rottboellia exaltata L.f., a new weed in sugar cane. The Sugar Bulletin, 1 12, pp. 82–8.Google Scholar
Smartt, J. (1961). Weed competition in leguminous grain crops in Northern Rhodesia. Rhodesia Agricultural Journal 58, 267–73.Google Scholar
Thomas, P. E. L. & Allison, J. C. S. (1975). Competition between maize and Rottboellia exaltata. Journal of Agricultural Science, Cambridge 84, 305–12.CrossRefGoogle Scholar
Villiers, T. A. (1972). Seed dormancy. In Seed Biology, vol. II (ed. Kozlowski, T. T.). New York: Academic Press.Google Scholar
Wesson, G. & Wareing, P. F. (1969). The induction of light sensitivity in weed seeds by burial. Journal of Experimental Botany 20, 414–25.CrossRefGoogle Scholar