Nutritional Status of Knotweed (Polygonum) Species Consumed as Vegetable in the Central Black Sea Region

This research was carried out to determine nutritional content and chemical composition of knotgrass species (Polygonum) consumed as vegetable in the Middle Black Sea Region. Survey and field studies started in spring of 2011 (April-May) and were carried out in Samsun, Amasya, Ordu and Tokat where these species were intense. In the survey studies, five species were identified in 35 knotgrass samples as Polygonum arenastrum (12 materials), Polygonum aviculare (9 materials), Polygonum salicifolium (9 materials), Polygonum setosum (2 materials) and Polygonum luzuloides (3 materials). In the research, the highest amount of dry matter in P. salicifolium (26.68 %), the highest ash content in P. setosum (10.21 %), the highest N and protein contents in P. luzuloides (3.31 % and 20.70 %) and the highest Vitamin C in P.aviculare (105.46 mg/100g-1) were determined. The highest K content in P. luzuloides, the highest Zn, Mn and Ca contents in P. setosum, the highest P and Na contents in P. arenastrum and the highest Cu, Mg and Fe content in P. salicifolium were determined. Amounts of mineral matter showed variation according to plant species, genetic factors and ecology of samples taken from. It was determined that many of nutritional properties studied were richer than some cultivated vegetable species