Efficacy Of Fungicides For Management Research Articles

Efficacy of fungicides for management of anthracnose (Gloeosporium psidii) in Guava

Anthracnose caused by Gloeosporium psidii (Colletotrichum psidii) is one of the major diseases causing significant losses in the production of guava. For its management, different fungicides namely; thiophanate methyl 70 WP, hexaconazole 5% EC, hexaconazole 4% + zineb 68% WP and carbendazim 12% + mancozeb 63% WP, mancozeb 75 wP and copper oxychloride 50 wP were screened against G. psidii under in vitro conditions through poisoned food technique. Carbendazim 12% + mancozeb 63% WP and thiophanate methyl 70 WP were found significantly effective by inhibiting the mycelial growth of the pathogen. All the fungicides tested in vitro were also evaluated through foliar spray for the management of disease under in vivo. Carbendazim 12% + mancozeb 63% WP and thiophanate methyl 70 WP proved to be effective for controlling anthracnose of guava under field conditions.

Efficacy of fungicides for management of banded leaf and sheath blight of Kodo millet caused by Rhizoctonia solani Kühn

Five fungicides viz. validamycin, hexaconazole, propiconazole, tricyclazole and carbendazim were evaluated as seed treatment alone and in combination with one foliar spray to manage the banded leaf and sheath blight (BLSB) incidence of Kodo millet caused by Rhizoctonia solani in susceptible cv. JK 155 under field conditions. Significant differences in relative lesion height (%) and grain yield was recorded in different treatments. Seed treatment with validamycin (2g kg−1 seed) followed by one foliar spray (0.2%) was found best by reducing the 85.3% disease severity and increasing the grain yield (25.8%) over check. Seed treatment and one foliar spray of hexaconazole (0.2%) and propiconazole (0.2%) were at par and next best treatments after validamycin by decreasing the disease severity 78.2 and 76.8%, respectively.

Field efficacy of fungicides for management of sheath blight and narrow brown leaf spot of rice

Sheath blight (caused by Rhizoctonia solani AG1-IA) and narrow brown leaf spot (NBLS, caused by Cercospora janseana) are among the most important diseases affecting rice production in Texas and in other regions in the southern United States. Strobilurin fungicides have been used extensively to manage these two diseases, especially sheath blight. Unfortunately, heavy reliance on use of fungicides with a single mode of action has induced the development of the strobilurin-resistant isolates of R. solani AG-1 IA in the U.S. NBLS, once considered a minor disease in the U.S, is growing in its occurrence and severity, while little scientific information is available on NBLS management. This created an urgent need for identifying other effective fungicides with different modes of action. A 6-year field study was conducted on rice to evaluate the efficacy of newly registered and unregistered fungicides in comparison to common fungicides for management of sheath blight and NBLS diseases. Single applications of the fungicides containing azoxystrobin, propiconazole, azoxystrobin plus propiconazole, trifloxystrobin plus propiconazole, fluxapyroxad, pyraclostrobin, flutolanil and antibiotics (validamycin and kasugamcyin) were made at the late booting stage. Sheath blight and NBLS severities were rated prior to harvest. All the fungicide treatments were effective in reducing sheath blight severity compared to the untreated control in each year. Propiconazole and fluxapyroxad were more effective in reducing NBLS than other fungicides. Along with reduced sheath blight and NBLS severities, fungicide-treated plots had higher yields than untreated plots.

Efficacy of fungicides for management of Alternaria blight of Linseed

Efficacy of fungicides for management of <i>Alternaria</i> blight of Linseed