The effects of geographical dispersal by man on the evolution of physiological races of the Corncockle(Agrostemma githago L.)
1973; Oxford University Press; Volume: 37; Issue: 3 Linguagem: Inglês
10.1093/oxfordjournals.aob.a084707
ISSN1095-8290
Autores Tópico(s)Botany and Plant Ecology Studies
ResumoComparisons were made between populations of Agrostemma githago growing amongst a variety of crops and collected in different parts of Europe to examine the effects of geographical location and crop plant associations on selective adaptation of the species. Populations varied from one another in their responses to photoperiod, their season of maturity, the partitioning of resources between leaves, stems, and flowers, and in characters such as floriferousness, mean seed weight, and seed production per plant. Analogies drawn between these characters and horticultural qualities of crop plants such as earliness, leafiness, or seed production suggest that it is possible that variations differentiating strains of crop plants may be present prior to their introduction to deliberate cultivation as a result of their occurrence in different locations. This implies that early cultivators of secondary crop plants in particular might have been able to take advantage of pre-existing diversity to extend cropping seasons, or to make use of special characters without need for deliberate selection or forethought.
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