Effect of temperature and GA3 on seed germination and seedling establishment of Rhododendron purdomii Rehd. et Wils

Abstract

Rhododendron purdomii Rehd. et Wils is an endemic and important ornamental plant species in China. The effect of temperature (20°C, 30°C and 20°C (16 h) /30°C (8h) and GA3 (0, 200, 400, 600, 800 and 1000 mg/l) on R. purdomii seed germination and early seedling establishment were studied. The results showed that there was little difference among the effects of three temperatures on germination time and germination speed, it significantly affected germination percentage, germination vigour and early seedling growth. High temperature had negative effects on seed germination, and the germination vigour at 20°C were significantly higher than those at two other temperature treatments, germination percentage and germination vigour were the lowest at 30°C; and the survival rate and leaf length of the seedlings at 20°C/30°C were far better than those at two other temperature treatments. Treatment with 600 mgl-1 GA3 for 24 h and 20°C/30°C temperature has a much higher survival rate and growth performance. Therefore, the findings from this study would greatly help the R. purdomii germplasm propagation, conservation and utilization.