Foliar-fertilizer therapy - a concept in integrated pest management.
Reuveni R., Reuveni M.
Author Affiliation: Department of Plant Pathology, ARO, Newe Ya'ar Research Center, P.O. Box 1021, Ramat Yishay 30095, Israel.
Crop Protection 17 : 111-118
Abstract : Data from laboratory studies indicate that foliar sprays of phosphate and potassium salts can induce systemic protection against foliar pathogens in various crops such as cucumber, maize, rose, grapevine, apple, mango and nectarine. Expression of disease tolerance is dependent on a number of factors including use of fertilizers and pesticides. Therefore, the possible dual role of NPK fertilizers in activation of the mechanism(s) which induce plant protection against pathogens was studied. Data from the application of this concept to various host-pathogen interactions are presented. A single phosphate spray of 0.1 M solution induced a systemic protection against powdery mildew in cucumber caused by Sphaerotheca fuliginea and against common rust in maize caused by Puccinia sorghi, and northern leaf blight (NLB) caused by Exserohilum turcicum [Setosphaeria turcica]. This systemic protection against powdery mildew in cucumber, common rust or NLB in maize was obtained on upper leaves after NPK fertilizer application on the lower leaves. In both the latter host-pathogens interactions, growth increase was also observed in maize plants as a result of one foliar spray of phosphates. In addition, it was evident throughout all the experiments that a single application of phosphates was effective in suppressing the lesions of powdery mildew on the diseased foliage of cucumber, greenhouse-grown roses and field-grown mangoes, nectarines and grapes. This phenomenon was investigated in combination with fungicides.