A new late ripening hybrid pomelo cultivar Xiamiyou

Abstract: Xiamiyou is a new late ripening table pomelo variety with excellent fruit quality. The variety was derived from a cross between kiyomi tangor and Shatian pomelo made in 2005 at Chongqing Beibei. In the spring of 2006, the hybrid seedlings were transplanted into the field for evaluation. From 2013, the offspring trees began to bear fruits consecutively. The fruit quality of a hybrid tree was found excellent. In the spring of 2014, the scion of the superior plant was collected and grafted on the sour pomelo rootstock for further observation and evaluation. The vigor of the trees is medium to strong, the crown has a round head in shape with drooping branches, after fruiting the tree’s crown gradually tends to open. The young leaves and young fruits have short pubescence, the leaf blade is oblong with an acute leaf tip and wedge-shaped leaf base, and the leaf margin is entire. The filaments are mostly separate, the style is erect, higher than the stamens, and the anthers are white in color, implying infertility. The fruits are broadly oval or conical oval, the average transverse diameter is 11.8 cm, and the longitudinal diameter is 9.65 cm, the average single fruit weight is 600 g, the fruit surface is yellow-orange, the fruit top usually is flat, the fruit base has no obvious short neck, and the fruit base radiation groove is more obvious. The peel is rough, and the peel thickness is 0.73 cm, which is thinner than that of Shatian pomelo, but the peel hardness is higher. The flesh is pale orange, crispy, and tender, the capsule wall is thin, and the juice sacs are large and juicy. The seed number per fruit is variable, ranging from 5 to 38, the seed is a single embryo. The edible rate of the mature fruit is 66.7%, the juice yield is 32.3%, the soluble solids content is 12.0%, the titratable acid content is 0.47%, the vitamin C content is 48.76 mg·100 mL-1 , and the flavor is sweet and less acidic. The spring shoots of Xiamiyou pomelo in the Beibei area of Chongqing sprout in late February, and the full-blooming stage is around April 21. The summer shoots sprout in late May and the early autumn shoots in late July to early August, and the autumn shoots inearly September. The fruit color break is in late October, the fruit ripening date is in late February, the fruits can be harvested until late April with no granulation. The trees have a high yield, the average yield of a 4-year-old plant is 43.1 kg, and the yield per 666.7 m2 can reach 1422 kg with a planting density of 5 m × 4 m. The trees display high resistance to anthracnose, canker, and cold. The tree should be planted in warm and no frost occuring areas with average annual temperature above 18 ℃, the lowest temperature should be above -3 ℃. The variety should be planted in slightly acidic soil with a deep soil layer, high organic matter content and good drainage and irrigation. The sour pomelo or pomelo could be used as rootstock for it.