EFFECT OF DIFFERENT INDUCERS ON CONTROLLING DAMPING-OFF AND WILT DISEASES OF LUPINE

The present investigation was carried out to study the effect of seed treatments of lupine plants (cv.Giza 2) with chemical inducers Bion (5mM) , salicylic acid (5mM) and saccharin (3mM) as well as as well as Paenibacillus polymyxa and Trichoderma harzianum as biotic inducers on the infection with Rhizoctonia solani and Fusarium oxysporum f. sp. lupine under greenhouse and field conditions.
Under greenhouse condition (Agricultural Research Centre, Giza) all treatments significantly reduced the percentages of pre- and post-emergence damping-off compared with the untreated control, the highest percentage of survived plants was achieved 92% by Bion and T. harzianum as well as fungicide Rizolex-T followed by salicylic acid and P. polymyxa as 88%. On the other hand, all treatments decrease significantly the incidence and severity of wilt, also increased the percentage of survived plants compared with untreated control.
Under field conditions at Giza and Ismailia Agricultural Research Stations (Giza and Ismailia governorates) during winter season 2016-2017, all the treatments decreased the percentage of pre- and post-emergence damping-off as well as the percentage of wilted plants and increased the percentage of survived plants compared with untreated control in two locations. At Giza research station, the highest percentages of survived plants were recorded with Rizolex-T followed by Bion, P. polymyxa, and salicylic acid. While at Ismailia, the highest percentage of survived plants were recorded with Rizolex-T followed by Bion, P. polymyxa, T. harzianum, and salicylic acid. Meantime, these treatments improved growth parameters i.e. plant height, number of pods/plant, the weight of seeds /plant and the weight of one hundred seed. The higher increase in seed yield (ton /feddan) was obtained with Rizolex-T and Bion treatments followed by Salicylic acid, P. polymyxa, and T. harzianum at two locations.
Activities of peroxidase (PO), polyphenol oxidase (PPO) enzymes and phenol content were determined. Bion treatment showed the highest increase in PO and PPO activity, and total phenols followed by salicylic acid and P. polymyxa treatments in the presence of R. solani or F. oxysporum. f. sp. lupine.