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Abstract The present work is an endeavor to discriminate among the different species of Teucrium L. naturally distributed in Libya by studying some chemoecological criteria such as macro and micronutrients elements, chemical composition of the essential oil, besides palynological and nutlet morphological characters. This study was carried out during the 2009 to 2010 including two flowering seasons. About 20 field trips were performed to cover 12 different locations (Lathroun-Ras- Elhellal, Shahhat-Susah, Wadi-Errieg, Awllad-Hezzam village (Garian), Wadi El-Quttarh, El-Rabtta-Elassbeh, Quasser-ElKhyaar (Wadi Jelabow), Sirut, Dryannah, Al-Hameda Escarpment and Tarhonah), extending about 4506.830 square kilometers east to west of Libya. The collected Teucrium comprised five endemic species (T.apollinis, T.barbeynum, T.davaeanum, T.lini-vaccarii, and T.zanonii) and three taxa as new records (T.capitatum, T.polium form 2, and T.polium subsp.flavovirens). Besides, T.brevifolium, T.campanulatum, T.fruticans and T.polium form 1 recorded in the other in Libyan Flora. The soil of the eastern region (7 locations) exhibited pH values ranging from 7.71 to 8.21 and EC values ranging from 0.252 to 1.78 mS/cm. The content of organic matter varied between 0.20 to 4.80% while organic carbon attained values between 0.12 and 2.80%. Calcium and Magnesium ions attained values between 32 and 170 and 2 and 18mg/l respectively, while Na+ and K+ attained values between 6 and 207 and 4 and 22 mg/l respectively. However, anions such as HCO- 3, Cl-, SO2- 4 and CaCO- 3 attained the range between 73 – 342, 18 – 511, 16 – 62 mg/l and 18 – 39.5% respectively. Furthermore, the concentration of most macro and micronutrient elements attained the highest values. T.barbeyanum attained the highest concentration of N, Ca and Fe while T.campanulatum exhibited the maximum concentration, of K, Mn and Zn. In addition, the maximum concentration of Na and Mg was achieved by T.apollinis and T.davaeanum. Surprising, each of the western and middle region was represented by only one species (T. polium with two forms) and one element (P). The western region was presented by four locations hold the taxa; T. capitatum, T. fruticans, T. linivaccarii and T. polium form 1. The pH of the soil solution comes out to be alkaline and EC ranged between 0.568 - 1.75 mS/cm while organic matter varies between 0.60 – 4.60 %). Organic carbon attained values percent between 0.35 and 2.65 %. With respect to cations Na+ attained a wide range of variation (3 – 76 mg/l) compared to the other cations (Ca2+, Mg2+ and K+).The Cl- anion attained a range between 12 – 110 mg/l which considered a wide range compared to other detected anions. The middle region was represented by one location which holds T. polium form 2 and exhibited soil solution pH value of 7.46 and EC value of 0.384 mS/cm. The organic matter and organic carbon attained percent values of about 10.32 and 6.00 % respectively. With regard to cations Ca2+ attained the highest value of 68 mg/l compared to the other ones. Similarly, HCO- 3 attained the highest value of 143 mg/l compared to the others. The pollen shape was prolate for (T.apollinis, T.brevifolium, T.capitatum, T.davaeanum, T.lini-vaccarii, T.polium form2 and T.zanonii) or subprolate for T.fruticans exhibited the phenomenon of dimorphism (perprolate and prolate). All studied Teucrium were tricolpate with. The exine ornamentation was recorded on three different regions, pollen surface, pole and operculum. Generally, the main type of sculpture was verrucate with various degrees of association with scabrate, perforate and faint perforate. Nutlet micromorphological characters were examined by using scanning electron microscope (SEM). Teucrium nutlets were discriminated into two groups; hairy (T.barbeyanum, T.brevifolium, T.campanulatum, and T.fruticans) and glabrous (T.apollinis, T.capitatum, T.davaeanum, T.Lini-vaccarii, T.polium and T. zanonii). In spite of that, each species was singled out by specific nutlet sculpture. |