Investigation on some autecology characteristics of Rohida (Tecomella undulate (Roxb.) seem.) in Sistan and Balouchestan province

The prominent influence of medicinal plants in the prevention and treatment of different diseases has led to an increasing trend of human societies towards them. In addition to numerous ornamental, industrial and agroforestry applications, Rohida (Tecomella undulate (Roxb.) seem.) from Bignoniaceae family is considered as one of the most valuable medicinal species in arid region due to the presence of efficient active ingredients such as lapachol with proven effects in the treatment of major diseases including cancer, aids, malaria and so forth. In this research, firstly the habitats of Rohida were identified in the province and then their climate characteristics, soil physical and chemical properties, phenology, some of morphological traits and companion plants were investigated. The evaluations showed that this plant had six small habitats with a low population of two yellow and orange morphotypes in the Balouchestan region, growing at altitudes ranging from 480 to 830 m above sea level, often in the direction of the waterways and the margin of the seasonal rivers with different aspects and low slopes. The climate of the habitats studied was warm desert and the soil texture was light to medium with an alkaline reaction. In addition to the phenological differences, a significant difference between the habitats in terms of their morphological traits and growth indices was observed that could be due to genetic and environmental factors, or both. The results of this study, regarding the decreasing population of this plant affected by various factors, especially the continuous drought caused by climate change, indicate that the Rohida in this province is exposed to extinction and urgent measures have to be taken toward its conservation, rehabilitation, and domestication.