Comparison of Fruit Quality, Leaf Fall during Winter, Water Flow Rate of Root and Tree Growth in Tankan onto Troyer Citrange and Trifoliate Orange

Abstract

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.