Aspects of the population ecology of charlock.

Published online
01 Jan 1981
Content type
Journal article
Journal title
Journal of Applied Ecology
DOI
10.2307/2402971

Author(s)
Edwards, M.

Publication language
English
Location
UK

Abstract

The numbers of Sinapis arvensis plants in 3 permanent quadrats in an arable field were examined over 3 years. Plant size was positively correlated with plant density at densities up to 20 plants/m2 suggesting that intraspecific competition was not operating. Experimental plots were established with different densities of S. arvensis and subjected to autumn or spring cultivation with or without a cereal crop over 3 years. Maximum numbers of plants were established in autumn and spring. The autumn populations arose from newly shed non-dormant seeds but were destroyed either by climate or cultivation. The spring population arose from dormant seeds after rain when the soil temp. at 10 cm was above 4.4 deg C. Climate was the major factor influencing plant population and reproductive capacity. Drought associated with high levels of radiation markedly reduced plant numbers and seed production in the second year. S. arvensis was suppressed by the presence of a cereal but competitive effects were subsidiary to those of climate and cultivation. Annual seedling emergence was found to be c. 2.5% of the seed population. Estimates from published data showed that the annual death rate of S. arvensis seed in soil is c. 17.9%. Using an exponential model it is possible to show that when potential parent plants are eliminated by herbicides, the viable buried seed population will be diminished by about one order of magnitude each decade but will be restored by one reproductive season every 11 years. From summary.

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