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.

In this study, in order to evaluate the characteristic of troyer citrange rootstock in tankan (Citrus tankan Hayata) ‘Tarumizu ichigo’, the fruit quality, leaf fall during winter, and the water flow rate of root were compared with those of Karatachi, common trifoliate orange rootstock. Furthermore, by the destructive harvest of tree, the dry matter weight and amount of starch in each organ were also compared. There were no significant differences between both rootstocks in sugar content and titratable acidity of fruit. The cumulative rate of leaf fall during winter was lower in the troyer citrange rootstock than in the trifoliate orange rootstock. The water flow rate of root with a diameter of 5 to 10 mm of troyer citrange rootstock was about three times that of the trifoliate orange rootstock. The trunk cross sectional area, trunk cross sectional area / root crown cross sectional area ratio, and dry matter weight of rootstock were larger in the troyer citrange rootstock than in the trifoliate orange rootstock. The amount of starch contained in the old branches including the trunk and the roots less than 5 mm in diameter were higher in the troyer citrange rootstock than in the trifoliate orange rootstock.