View/Open - ResearchSpace - University of KwaZulu-Natal
View/Open - ResearchSpace - University of KwaZulu-Natal
View/Open - ResearchSpace - University of KwaZulu-Natal
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2.11 IN VITRO FLOWERING<br />
Literature review<br />
Florogenesis is divided into six phases for most geophytes. These include induction,<br />
initiation, differentiation, floral stalk elongation, maturation and growth <strong>of</strong> the floral<br />
organs, and anthesis. (FLAISHMAN & KAMENETSKY, 2006). Factors that affect<br />
florogenesis include the genetics <strong>of</strong> the plant and its environment (FLAISHMAN &<br />
KAMENETSKY, 2006). After induction <strong>of</strong> flowering the vegetative meristem ceases<br />
leaf production during flower initiation to allow for more resources for flower initiation<br />
(FLAISHMAN & KAMENETSKY, 2006).<br />
Smoke and smoke solutions have been used to promote flowering in geophytes.<br />
These include Narcissus tazetta, a freesia hybrid and Watsonia spp. (IMANISHI,<br />
1983; UYEMURA & IMANISHI, 1984; LIGHT et al., 2007). LIGHT et al., (2007) found<br />
that a 1:500 (v/v) smoke water solution promoted the flowering <strong>of</strong> corms <strong>of</strong> Watsonia<br />
spp., which is in the same subfamily as Romulea. Corms <strong>of</strong> Freesia sp., a species in<br />
the same tribe as Romulea, were stimulated to flower using a smoke treatment<br />
(UYEMURA & IMANISHI, 1984).<br />
In a study <strong>of</strong> the plant-soil relationship in the habitat <strong>of</strong> R. columnae it was found that<br />
soil N, P and K was reduced during the generative growth stage whereas the soil<br />
organic matter, pH, and CaCO3 levels were increased (KÖK et al., 2007).<br />
It is better to use large plants with large, matured storage organs for florogenesis<br />
studies, as it is common for a plant with a small storage organ not to flower<br />
(FLAISHMAN & KAMENETSKY, 2006).<br />
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