Potency of some synthetic stimulants and root exudates on the germination of Phelipanche spp [Phelipanche spp. çimlenmesi üzerine bazi{dotless} sentetik stimulantlari{dotless}n ve kök salgi{dotless}lari{dotless}ni{dotless}n potansiyel etkisi]

Broomrapes (Orobanche/Phelipanche spp.) are considered as the most important problem of some cultivated plants, especially belonging to Solanaceae and Fabaceae families. Phelipanche ramosa L. and Phelipanche aegyptiaca (L.) Pers. cause serious problems especially in tomato grown areas in Turkey and the other Mediterranean countries. This study was conducted to determine the effect of some synthetic stimulant substances and root exudates on the germination rate of the broomrape species under controlled laboratory conditions. GR24 (0.1-1 ppm), GR7 (0.1-1 ppm) and GA3 (10 ppm) were used as synthetic germination stimulant substances; otherwise flax, cotton, soybean, bean, pea, cowpea, tomato, lentil, cucumber and tobacco seedlings were used for root exudates. According to average results of the trials; synthetic stimulants and root secretions increased the germination rate of P. ramosa at the range of 50-77% and 0-16% respectively, otherwise average data for P. aegyptiaca are 62-95% and 0-63%. As a result of the studies it was determined that synthetic stimulants were significantly increased the germination rate of Phelipanche species

Chemometrics-Assisted Optimization of Beta-/Gamma-Tocol Separation on a C₃₀ Stationary Phase in Reversed-Phase LC

This paper presents a chemometrics-assisted optimization study to improve the separation of tocopherol (-T) and tocotrienol (-TT) homologues on a C30 stationary phase in reversed-phase HPLC. The HPLC settings were optimized using a central composite design and the response surface methodology. Flow rate, column temperature, and mobile phase composition were chosen as independent variables. Peak resolution (Rs), analysis time (tR), and peak symmetries of the tocopherol isomers were chosen as response variables. Optimum performance in terms of Rs was obtained at a flow rate of 0.31 mL min−1, a temperature of 8.70 °C, and % B content (methyl tert-butyl ether: methanol: water, 80:18:2, v/v/v) in the mobile phase of 38.12%. The analysis of variance and regression analysis gave adjusted R2 values of 0.9841 for Rs, 0.9850 for tR-(α-T), 0.9853 for tR-(β-T), and 0.9204 for the peak symmetry of β-T. This confirms the good agreement of experimental data with predicted values. The close eluting peaks of β-/γ-tocol could be baseline separated at the optimized conditions at a minimized analysis time. Empirical second-order polynomial models were derived that gave statistically high significances (P < 0.0001). Hence, the models can be successfully employed to predict the optimum separation conditions of co-eluting peaks of β-/γ-tocols. The optimized method was successfully applied to determine the individual tocol homologues in various cold pressed edible oils. Total contents ranged from 15 to almost 2600 mg tocol kg−1 oil