... the powdery mildew, brown leaf rust and yellow rust of wheat, powdery mildew of cucumber, potato, pea and rubber etc.Hazard ... the powdery mildew, brown leaf rust and yellow rust of wheat, powdery mildew of cucumber, potato, pea and rubber etc.Hazard ... the powdery mildew, brown leaf rust and yellow rust of wheat, powdery mildew of cucumber, potato, pea and rubber etc.Hazard ...