Efficacy of fungicides against yellow rust of wheat under irrigated conditions in Punjab

The domestication of wheat paved way to meet the nutritional requirements of the growing world population. However, wheat production is continuously threatened by various biotic stresses , among them the most destructive is yellow rust caused by Puccinia striiformis f.sp. tritici. Fungicide application is an effective mode to manage the disease under high risk conditions. In the present study, different formulations of strobilurins and triazole based fungicides were evaluated against yellow rust, under artificial epiphytotic conditions in field, for two consecutive years. Fourteen fungicidal treatments were used and each treatment was applied twice at 15 days interval starting from the appearance of symptoms. The results showed that all the fungicides significantly reduced yellow rust severity in comparison to untreated check/control. Tebuconazole 430 g/l SC (@ 0.05%) performed best giving almost complete control of yellow rust, followed by azoxystrobin 18.2% w/w + cyproconazole 7.3% w/w SC (@ 0.10%), pyraclostrobin 133 g/l + epoxiconazole 50 g/L SE (@ 0.18%), trifloxystrobin 100g/L + tebuconazole 200 g/L SC @ 0.10% and 0.12%, azoxystrobin 11% + tebuconazole 18.3% w/w SC (@ 0.15%), pyraclostrobin 133 g/l + epoxiconazole 50 g/L SE (@ 0.12%), azoxystrobin 12.5% + difenoconazole 12.5% W/V SC @ 0.14%, and azoxystrobin 23% SC @ 0.10%. Maximum average disease severity of 82.50% and minimum mean yield of 17.54q/acre was observed in control. Hence, any one of these fungicide formulations can be used for irrigated wheat system to effectively manage yellow rust under high disease pressure conditions with attainment of potential yields.