Effect of Benzothiadiazole and Salicylic Acid Resistance Inducers on Orobanche foetida Infestation in Vicia faba

The broomrape or orobanche (Orobanche foetida) is considered as an important agricultural problem of faba bean (Vicia faba var. minor) production in Tunisia. The effect of salicylic acid (SA) and benzothiadiazole (BTH) on the induction of faba bean resistance to O. foetida was studied. Three application methods (seed soaking, foliar spraying and watering) were used. SA and BTH treatments reduced broomrape infestation under controlled conditions in pot and Petri dish experiments. In pot experiment, SA and BTH treatments reduced broomrape total number. Seed soaking treatments were more effective than foliar spraying and watering. In Petri dish experiment, O. foetida seed germination and the number of orobanche tubercles were reduced. The most efficient method was watering for SA and BTH treatments. This reduction was associated to a delay in the tubercle formation. The different application methods of SA and BTH treatment attest that the induced systemic resistance to O. foetida can be used in integrated management of broomrapes.