Bio-efficacy evaluation of a new copper based fungicide against foliar diseases of 'Cavendish' banana under highland condition in Mindanao, Philippines

The control of banana leaf diseases is one of the major constraints for the production of dessert bananas for export. Their management requires frequent application of systemic and contact fungicides. Ionic copper concentrate (ICC) is a new ionized copper formulation developed for control of leaf diseases. In a yield trial ten tissue cultured banana plantlets (‘Williams’) were used per plot, to compare three rates of ICC (100, 125 and 150 ml/ha) alone and in combination with mineral spray oil (7 L/ha plus 0.07 L/ha emulsifier) against the standard Mancozeb 600 OS (with 7 L/ha mineral oil plus 0.07 L/ha emulsifier) and Chlorothalonil 720 SC fungicides for control of foliar diseases under highland condition (870 m a.s.l.) in Mindanao, Philippines. ICC rates in combination with mineral oil significantly reduced Mycosphaerella fijiensis compared to the ICC with no oil. ICC at the different concentrations with mineral oil also resulted in a comparable number of functional leaves relative to the standard Mancozeb 600 OS and Chlorothalonil 720 SC treatments. ICC 125 and 150 ml/ha with Phyllosticta musarum mineral oil gave a comparable result compared with the standard Mancozeb 600 OS against leaf freckle (Phyllosticta musarum). However, the different rates of ICC with oil were inferior to Chlorothalonil 720 SC for the control. All rates of ICC without oil were inferior compared to the standard fungicides and compared to ICC with mineral oil against Mycosphaerella fijiensis and Phyllosticta musarum. Similarly, all rates of ICC applied alone had no significant effect against Haplobasidium sp. causing Malayan leaf spot. The different rates of ICC with mineral oil reduced Malayan leaf spot compared to the ICC without oil, but were inferior to both standard fungicides. All treatments of ICC with or without oil showed no toxicity on fruit or oil flecking on the leaves.