Breeding of a new red pomelo variety Zhengtian 1043

Abstract: A new pomelo cultivar Zhengtian 1043 was found from the bud mutation of Shatianyou (Cit-rus grandis Osbeck), which has been widely planted in southern China. This bud sport was discovered from a citrus grove in 2010. The bud of the mutant was selected and then grafted on Suanyou root-stocks. The cultivar was registered in 2019 after DUS testing. This cultivar has an upright tree shape and a medium branching ability, and shows self-incompatibility or weak self-compatibility. It is neces- sary to plant 10% Suanyou or Miyou (Citrus grandis Osbeck) of the total trees in an orchard to provide enough pollens for pollination. The leaf is oval with a dark-green color. The leaf size and shape of the mutant were almost the same as those of Shatianyou. Flower of the new cultivar is raceme, white and long obovate. Each flower has 26-34 anthers, with light yellow sacs and yellow pollens. There are erect and long styles, and stamens are sloping toward the style. The length of stamen is higher than the pistil when the flowers are in full bloom. The stigma is oblate. The appearance index of fruits is different be-tween both cultivars. The fruits are larger than the parent, pear-shaped with a smooth and yellow color peel, and weighing about 1380 g. The length of fruit neck is shorter than that of Shatianyou. It is easier to peel than the parent. There are 78 seeds on average per fruit and the eatable proportion is 46%. The pulp color of different fruits varies from light-red to red, and the texture is little bit hard. The total solu-ble solid, total sugar and titratable acid contents are 10.7%, 5.6% and 0.69%, respectively, and the ascor-bic acid content is 44 mg·100 mL-1. The SSR molecular markers were selected to discriminate the dif- ference between new cultivar and the parent. The results showed that two cultivars were different at ge-netic level. The bud-breaking time, flowering and fruit ripening period of new cultivar are basically the  same as those of Shatianyou. The spring shoots started to grow in early February, the flower bloomed in early to late February, and the fruit ripened in early November in Guangzhou city of Guangdong prov-ince. The suitable growing areas for Zhengtian 1043 are also the same as for Shatianyou.