Effect of Light and Temperature on Germination of Lychee Pollen

Abstract

The effects of light and incubation temperatures on pollen germination of commercial lychee cultivars were studied. The pollen was germinated in liquid medium by using a hanging drop technique in an incubator. The pollen was germinated in liquid medium by using a hanging drop technique in an incubator. The germination percentage of ‘Honghuay’ pollen incubated in either the presence of light or the darkness at 25๐C for 24 hours was not distinct. The pollen germination ‘Honghuay’ from ‘Jakapat’ at any incubation periods in dark at 25๐C for 3- 24 hours was not significantly different. Averaged germination percentage of both Cultivars sharply increased to 69.2% when the incubation period was prolonged to 3 -12 hours. Extending the duration of incubation beyond 18 and 24 hours, germination per – centage was slowly increased to 87.4 and 89.0% respectively. As temperatures increased, the percentage of pollen germination of all ‘Honghuay’ ‘Jakapat’ ‘Ohea’ and ‘Kimcheng’ lychee tended to increase. Averaged over the four cultivars, 2.0% of pollen germinated at 10๐C, this increased to 14.7 49.6 60.1 and 63.9% when the incubation temperature was increased to 15 20 25 and 30๐C respectively. Raising the incubation temperature to 35๐C resulted in decreased percentage germination to 59.8%. The best temperature of pollen germination for all four cultivars was between 25 and 35๐C.