Coning and sex ratio of Encephalartos transvenosus at the Modjadji Nature Reserve

From a random sample of 638 mature plants examined during 1987, the developing cones yielded a sex ratio of 2,3 males to 1 female. The sex expression of the taller plants (2,6 m – 9,5 m) during 1987 was 7 males to 1 female. This suggests a preferential dying off of the old females and/or a stronger decline in the production of cones by the ageing females compared with their male counterparts. Plants in the l,6-m – 3,5-m stem height range had the highest coning frequency during 1987. An increased water availability as well as fire in the preceding year appear to enhance coning whilst fire in the preceding year also appears to stimulate the females more than the males to cone during the ensueing season.

• Publication year

  1989

• Venue

  South African Journal of Botany

• Publication date

  1989-02-01

• Fields of study

  Biology, Environmental Science

• Identifiers
  DOI 10.1016/S0254-6299(16)31235-2
• External record

  Open on Semantic Scholar

• Source metadata

  Semantic Scholar

• No claims are published for this paper.

• No concepts are published for this paper.

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