Flowering and Inflorescence Development of Lachenalia aloides `Pearsonii' as Influenced by Bulb Storage and Forcing Temperature
The effect of bulb storage and forcing temperatures on growth, flowering, and inflorescence development and the death of inflorescence (blast) of Lachenalia aloides Engl., `Pearsonii' was investigated. Following development of about 5 florets, bulbs were stored at 10, 12.5, 15, 20, and 25 °C for 15, 30, or 45 days and forced in greenhouses at 17/15 °C and 21/19 °C. Flowering was accelerated, and leaf length and floret number were reduced, when bulbs were stored at 10, 12.5, or 15 °C for 45 days compared to storing at 20 or 25 °C. Flowering was further accelerated by forcing at 17/15 °C compared to 21/19 °C. When bulbs were stored at 10, 15, 20, or 25 °C for 4 weeks and grown in greenhouses at 17/15 °C, 21/19 °C, 25/23 °C, and 29/27 °C, the incidence of inflorescence blast was increased when bulbs were stored at 10 and 15 °C and forced at 25/23 °C compared to low temperatures. Bulbs were forced in greenhouses maintained at 18/16 °C, 22/20 °C, or 26/24 °C for 12 weeks. During forcing, plants were subjected to constant or alternating forcing temperatures at 4-week intervals. Inflorescence blast occurred when the temperature was 26/24°C during the first 4 weeks after potting. Storing Lachenalia bulbs at 10° to 15 °C before potting then forcing at 17/15 °C accelerated flowering and produced quality plants with short leaves and floral stems. Inflorescence development during bulb 10 °C treatment and inflorescence blast that occurred after only 3 days of 35 °C was demonstrated using scanning electron microscopy and magnetic resonance imaging techniques.
