Effect of some biofertilizers and biofungicides applications on control onion root-rot disease

Abstract

Five biofertilizers and biofungicides namely, (Cerialien, Biogen, Nitrobein, Phosphoren and Potassiumag) and (Rhizo-N, Bio-Arc, Plant-guard, Biozied and T-34) were used to evaluate their ability to protect onion plants (Giza 6 Mohassan var.) against root rot diseases, which mainly caused by Fusarium oxysporum f.sp. cepae causing Fusarium basal rot, Pyrenochaeta terrestris causing pink root rot and Sclerotium cepivorum  causing white rot disease as well as improving growth and yield of onion under greenhouse conditions during 2018/2019 and 2019/2020 growing seasons. Data clearly showed that the tested biofungicides decreased the disease severity of onion bulb root rot as compared with the check treatment. The treated soil with different biofungicides significantly decreased the disease severity of onion  root rot diseases compared with the control. T-34 biocontrol at the rate of 2 and 3 g/kg soil was the most effective biofungicide in minimizing disease severity caused with the tested fungi followed by Biozied and Rhizo-N at the same concentrations during 2019/2020growing seasons. Also, Treated transplants with commercial biofertilizers i.e. Cerialien, Biogen, Nitrobein, Phosphoren and Potassiumag at 3 g/Kg soil and planted in infested soil with tested pathogenic fungi caused the highest reduction of the tested pathogenic fungi under greenhouse. As mean treated transplants with Nitrobein gave the greatest reduction of root rot diseases caused by F. oxysporum f. sp. cepae, P. terrestris and S. cepivorum, when used under greenhouse conditions during 2018/2019 and 2019/2020 growing seasons. Moreover, all these treatments significantly increased growth parameters i.e. fresh bulb weight, dry bulb weight and bulb diameter as compared with the check treatment