Effects of Two Kinds of Rootstocks on the Growth of Navel Orange (Citrus sinensis Osbeck)Young Tree and the Annual Changes in the Contents of Carbohydrates in Leaves

It was conducted with ’Nice’ navel orange (Citrus sinensis Osbeck) two-year-old young tree whose rootstocks were Red tangerine +Trifoliate and Red tangerine +Rough lemon somatic hybrid, Troyer Citrange and Swingle Citrumelo sexual hybrid. Study on the effects of rootstocks on the growth and the annual changes in the contents of carbohydrates in leaves through potted experiment. The results are the following. Red tangerine + Trifoliate grew more vigorously than the other three. The number of blossoms of Red tangerine +Trifoliate was larger than the other three too. Difference in chlorophyll a/b and carotenoid content showed insignificance among all rootstocks. Different rootstocks remarkably influenced all contents of chlorophyll. Rootstocks obviously influenced the tendencies of the annual changes in the contents of the soluble sugar and the starch in leaves. During the dormant period, Red tangerine+ Trifoliate had higher content of the soluble sugar and the starch in leaves, and Red tangerine+ Rough lemon was to the contrary. During the growing period, Red tangerine+ Rough lemon had the lowest contents of the soluble sugar and the starch in leaves, and Red tangerine+ Trifoliate was between 2 sexual hybrids. The utilizations potential of these two somatic hybrids were discussed intensively.