The Effects of Calcium Formate Spraying on Anthracnose of Mango (Mangifera indica L.) Variety ‘Lippens’

Abstract

In order to investigate the effects of inorganic element treatments on the reduction of anthracnose on mango ‘Lippens’, calcium formate, which has been shown to be effective in other crops, was used to evaluate its effectiveness on anthracnose incidence, fruit quality and peel. The results of the field tests showed that this occurrence in the calcium formate plots was significantly lower than that in untreated plots at any time. There was no difference in fruit quality between the treatments, indicating that calcium formate had no effect on quality. In the susceptibility test, no inhibitory effect on mycelial growth and spore germination of carbonaceous fungus directly was observed, but in the wound inoculation test, lesion expansion was significantly suppressed in the treated plots. These results suggest that the effects of calcium formate were not due to growth inhibition of the anthracnose fungus directly, but was more likely due to its effect on the plant. The calcium and hexametaphosphate-soluble pectin contents of the fruit peel of the treated plots were 292.1 mg/100 g and 3.83 g/100 g, respectively, significantly higher than those of the untreated areas. Fruit firmness during the ripening period was significantly higher in the former plots. These results suggest that the application of calcium formate to ‘Lippens’ produces insoluble pectin bound to intracellular pectic acid, which inhibits the degradation reaction by pectinolytic enzymes, maintains fruit firmness and inhibits anthracnose invasion.