Response of Some Morpho-physiological Characteristics of Borago (Borago officinalis) to Nano Particles of Titanium Spraying

Brago is an important medicinal plant. This study, thus, was conducted with different levels of nano particles of titanium (0.01, 0.03 and 0.05%) and elemental titanium on its different growth stages (4-5 leaf, flowering and after flowering) with four replications in a factorial experiment based on randomized complete block design at the Agricultural Field of Rement Village of Babol, Mazandaran, Iran, in 2012. Results showed that there were a significant differences between treatments of titanium, time of treatments and between their interactions. Among the traits under study, leaf fresh weight, leaf dry weight, stem fresh weigh at 1% and plant hight, stem dry weight, total plant fresh weight and total plant dry weight at %5 levels of probabilities showed significant differences for their interaction between different treatments of titanium and different stage of development. The highest plant height, leaf dry weight and plant fresh weight and plant dry weight were produced when nano particles of titanium applied after flowering stage. Where as, the highest fresh leaf, fresh stem weight and total plant fresh weights were obtained when plants treated with titanium at flowering stage. On the other hand, dry weight of flowering branches showed significant negative correlation with GPX antioxidant enzyme. The lowest GPX antioxidant enzyme was produced when nano particles of titanium were applied after flowering stage at 0.01% probability level. As a whole, the results of this experiment suggest that there are significant differences among titanium treatments when they are applied at different growth stages of this plant. This study also showed that application of nano particles of titanium after flowering of this plant increased its flowering branches