Effects of Probenazole (Oryzemate^®) on Rice Plants with Reference to Controlling Rice Blast

Abstract

After treating rice plants by submerged application with probenazole no changes were noted in the siliciferous cells in the leaves, no morphological changes in the leaf tissue and no anti-fungal activity in leaf exudates were detected. When rice plants were treated by submerged application of probenazole and subsequently inoculated with the blast fungus (Pyricularia oryzae CAVARA) peroxidase activity (oxidation of phenolic substances) increased and an anti-conidial factor in the rice leaf increased. Also the increase of the factor was observed in rice plants treated by the chemical but not inoculated. A part of the appearance of induced resistant characteristics were thought to be similar to a reaction of resistant rice plant. The induction of resistant characteristics were largely inhibited by a heat shock upon rice plant indicating that the event was host mediated reaction. Probenazole (submerged application) appears to control the blast disease in rice by a combination of the events, such as inhibiting sensitive stages in the life cycle of the blast fungus and also activating the host defence.

Efficacy of probenazole for control of southern corn leaf blight

“…In addition, a low dose of Oryzemate (1.8 kg a.i./ha) was applied to control SCLB and did not contact the pathogen directly by a soil-surface application. In accordance with previous studies, 10,11,13,14,18,19,20,26) it is suggested that the effect of Oryzemate to control SCLB could be attributed to the activation of systemic resistance in maize.…”

“…26,27) The persistent activity of Oryzemate was attributed to the host-mediated defense action. [11][12][13][14][15][16][17][18] Despite extensive use of Oryzemate over many years, development of resistance in the target fungus has not been observed 26) ; thus, using Oryzemate to control SCLB may reduce the outbreak of C. heterostrophus due to the development of resistant strains.…”

Antagonistic Interaction between Systemic Acquired Resistance and the Abscisic Acid–Mediated Abiotic Stress Response in Arabidopsis

“…Among these chemicals, 2,6-dichloroisonicotinic acid (Mé traux et al, 1990;Uknes et al, 1992), benzo(1,2,3)thiadiazole-7-carbothioic acid S-methyl ester (BTH) Gö rlach et al, 1996;Lawton et al, 1996), N-cyanomethyl-2-chloroisonicotinamide (Yoshida et al, 1990;Nakashita et al, 2002a;Yasuda et al, 2003a), 3-chloro-1-methyl-1H-pyrazole-5-carboxylic acid (Nishioka et al, 2003;Yasuda et al, 2003b), andN-(3-chloro-4-methylphenyl)-4-methyl-1,2,3-thiadiazole-5-carboxamide (Yasuda et al, 2004) induce SAR by acting at the point of SA accumulation or downstream in the SAR signal transduction pathway. By contrast, probenazole and its derivative, 1,2-benzisothiazol-3(2H)-one1,1-dioxide (BIT), induce SAR by stimulating the SAR signaling pathway upstream of SA (Watanabe et al, 1979;Yoshioka et al, 2001;Nakashita et al, 2002b). Some of these chemicals have been used to manage diseases in crops.…”

Different Responses of Two Genes Associated with Disease Resistance Loci in Maize (Zea maysL.) to 3-allyloxy-1,2-benzothiazole 1,1-dioxide

“…Probenazole (3-allyloxy-1,2-benzisothiazole 1,1-oxide; PBZ) has been widely used with partially resistant rice (Oryza sativa) cultivars to control rice blast disease for decades in Asia (Watanabe et al, 1979). PBZ induces systemic acquired resistance (SAR)-like disease resistance in rice (Sakamoto et al, 1999).…”