Impact of Sorghum halepense (L.) Pers. on the Species Richness in Native Range

Sorghum halepense (L.) Pers. is one of the most important weed species that has a very large climate niche, with favorable growing conditions in the world in managed and unmanaged areas. This study aimed to determine the species richness and some physical features of S. halepense in Yalova province, which is located in the Mediterranean biogeographic section in Turkey. The variability of colonized habitat by this species was studied at six sites with 120 samples in the S. halepense present and not-present areas. The total numbers of plant species in S. halepense present areas (36 taxa) were lower than in S. halepense not-present (70 taxa). Convolvulus arvensis (70%), Cynodon dactylon (50%) and Cichorium intybus (30%) were the most frequent species occurring along with S. halepense . In addition, Phragmites australis (7%) and Cyperus rotundus (8.3) were identified as a single plant combination with S. halepense in some samples. In addition, Amaranthus retroflexus (28.3%), Rumex crispus (20.0%) and Datura stramonium (18.3%) were the most frequent species that occurred in S. halepense not-present sites. The success of S. halepense ongoing risk can be explained by its wide ecological tolerance and strong competitive ability as an expanding species. For this reason, necessary measures should be taken for controlling the distribution of S. halepense in each region and risk analysis should be performed even if in the native range.