EFFECT OF NANOPARTICLES AND BIOAGENTS TO INDUCE RESISTANCE IN WHEAT PLANTS AGAINST POWDERY MILDEW DISEASE

Abstract

Powdery mildew disease caused by Blumeria graminis f. sp. tritici (Bgt) is one of the most serious diseases of wheat (Triticum aestivum L. emThell.) in Egypt and world-wide. The effect of nanoparticles of silicon and titanium, bioagents and chemical inducers against powdery mildew disease of wheat plants was studied, under greenhouse and field conditions. Nanoparticles of silicon and titanium were biologically synthesized from different bacterial and fungal isolates of wheat rhizosphere and phyllosphere. Transmission electron microscopy (TEM) revealed that Pseudomonas putida (PpFT1) produced the small size of both nano silicon particles (SiNPs) which ranged from 1.52 to 8.73 nm and nano titanium particles (TiNPs) from 5.81 to 8.95 nm. While, SiNPs and TiNPs that synthesized by Trichoderma harzianum (ThFT1) ranged from 5.0 to 9.0 nm and 2.0 to 16.0 nm, respectively. The SiNPs and TiNPs were tested as seed soaking and subsequent foliar spray, treatment, to control powdery mildew on wheat seedling under greenhouse conditions. The most effective treatments were SiNPs at concentration of 100 and 150 ppm synthesized by P. putida (PpFT1) and Bacillus subtilis (BsBN3) which reduced the powdery mildew severity by 83.3, 89.7, 84.6 and 91.0 % respectively. While, SiNPs at concentration of 150 ppm synthesized by T. harzianum (ThFT1) reduced the powdery mildew severity by 82.0 %, TiNPs synthesized by P. putida (PpFT1) at concentration of 150 ppm reduced powdery mildew severity by 93.5 % followed by TiNPs synthesized by P. putida (PpFT1) at 100 ppm, Bacillus subtilis (BsBN3) at 150 ppm and T. harzianum (ThFT1) at 100 and 150 ppm which reduced the powdery mildew severity by 84.6, 80.7, 78.2 and 80.7 %.