Comparison of ornamental characters between Chinese flowering crabapple and 'Royalty' crabapple

'Royalty' crabapple (RC) (Malus hybrid) is one of the most favored introduced crabapples in China. Chinese flowering crabapple (CITC), Malus spectabilis (Aiton) Borkh, has been used for ornamental trees in China for a long time. With the beginning of breeding research on crabapple in China, it is important to compare the ornamental characters between CFC and RC. The 3-year-old grafted trees on 6-year-old Malus robusta (Carr.) Rehd (Pyrus prunifolia var. robusta Carr) rootstocks were used to compare their ornamental characters between CFC and RC. The results of 2004-2006 investigation in Beijing showed that CFC had a higher flower density per length of shoot, larger flower size and more petal number in each flower than RC. The petal color of CFC changed from red to pink or white with the opening of flower, though showing a lighter color, but its leaves kept green, unlike RC which has dark red leaves throughout its life. CFC had more fruit number per shoot length, larger fruit size, and later fruit abscission, but with green fruit color unlike 'Royalty', whose fruits showed a dark red color. CFC had a stronger tree vigor, with more shoot growth in length and diameter than RC.