Modelling flowering time of rhododendron

Abstract

Plant phenology, primarily affected by temperature and photoperiod, is a useful indicator to study the effects of climate change. Even though, it is a proven fact that climate change has affected the phenology of a wide range of species, but degree of impact varies across the species. It is very important to understand the sequence and timing of developmental stages (phenological events) such as bud development and flowering time in response to change in environmental conditions. Along with the identity of being a national flower of Nepal, the beauty of the rhododendron flower welcomes thousands of foreign tourist every year. Non uniformity in flowering time of rhododendron in recent years across the region is commonly expressed by local people and also reported in recent local news. To understand the flowering time behavior of rhododendron a flowering time model was developed in this study. The good agreement between observed and simulated flowering time during the calibration process showed that the developed model has the potential for predicting flowering time of Rhododendron arboreum in response to temperature and photoperiod. Simulation results (Late flowering in higher elevation and early in lower elevation) showed that there exists a linear relationship between altitude and flower onset time of rhododendron in Nepal. In addition, flowering time prediction in response to future climate data showed that phenology of rhododendron is going to shift early as the year advances.