Morphological variation in Heliotropium digynum growing in four locations of the central region of Saudi Arabia

This study was carried out to compare the morphological features of the floral and shoot systems of Heliotropium digynum that were collected from different locations in the central region of Saudi Arabia. Heliotropium digynum is a member of Boraginaceae family. The plant is a shrub that has an ecological importance. The height of the plant differs from one population to another and the difference in length of the inflorescences can be attributed to environmental factors, such as rainfall or type of soil and temperature. These plants can grow in different temperature zones (including temperate and warm), and in arid regions, flourishes greatly, in terms of height, spread, leaf area, length of inflorescences, number of flowers, and speed of development, when it grows in sandy soil disturbed by human activity, species or individuals compared to specimens growing on hard soil and frequented by the public.