REPRODUCTIVE BIOLOGY, PROPAGATION AND EX SITU CONSERVATION STRATEGIES OF A CRITICALLY ENDANGERED KENYAN HARDWOOD SPECIES: IXORA SCHEFFLERI K. SCHUM. & K. KRAUSE SUBSP KENIENSIS. BRIDSON

Abstract

Ixora scheffleri K.Schum.& K.Krause subsp. keniensis Bridson is a critically endangered Kenyan hardwood species on the brink of extinction in its area of endemism. The pollination ecology and breeding system of I. scheffleri subsp keniensis was investigated at the singular natural population at the Mount Kenya region of Kenya in an attempt to unravel the causes of of its decimation. I. scheffleri subsp keniensis was in flower from November to March (Fruits April to July) with a peak flowering in February. All the 8 insect species regularly visiting the flowers frequently made contacts with the stigmas and they carried copius amounts of pollen. Three Lepidoptera, two Diptera, one Coleopteran one Hymenoptera and one Thysanoptera were the visitors that frequently visited the flowers. I scheffleri subsp keniensis produced fruits through both self and cross-pollination. The tree species showed high fruit production under natural, open pollination conditions. The control, wind and/or insect pollination treatment resulted in 79.5% fruit set. The spontaneous autogamy treatment resulted in 36.5% fruit set. No germination of I. scheffleri subsp keniensis seeds was observed either in the field or in the laboratory experiments.
The effect of Indole butyric acid (IBA), Napthalene acetic acid (NAA), Propagation media, season, leaf area, cutting position on mother plant and cutting length on rooting was evaluated. The Forest soil: Sand (FRS: S) rooting medium recorded the highest percentage of rooting after 8 weeks (69%). This was significantly different (p