Breeding of new guava cultivar Chaohong

Abstract: Chaohong guava is a new variety that has been bred by a single plant and grafted for many years, and has excellent comprehensive traits. In 2011, a group of native guava was first discovered in Qiandong town, Raoping county, Chaozhou City. After years of field investigation and quality analysis, the excellent solid plant line (named No. 3) was found. In 2017, a grafting experiment was carried out in Chaozhou Fruit Research Institute, and the results showed that the traits and quality of grafted offsprings (V1) were consistent with those of the mother tree. In 2019, branches were collected from V1 offsprings as scion, and after years of multi-generation grafting, it was found that the grafted offsprings could still maintain the excellent genetic traits of the mother tree (No. 3). In 2019—2022, a number of physical and chemical quality indexes of guava fruit were tested, and the results showed that the genetic performance of guava varieties was stable. In December 2022, the on-site expert review was conducted, and in November 2023, it was approved by the Guangdong Provincial Crop Variety Examination and Approval Committee (Approval No.: Guangdong Fruit Review 20230008). The variety is of good quality and commerciality, with an average fruit weight of 116.2 g and uniform size. The fruit shape is oval, with a fruit shape index of 1.18, soluble solid content of 10.8%, total sugar content of 7.5 g·100 g^-1 , vita-min C content of 285 mg·100 g^-1 , titratable acid of 5.04 g·kg^-1 , and edible rate of 99.6%. The peel is shiny yellowish-white; The flesh is red, tender and fragrant; The seeds are few and concentrated at the junction of the pulp and the heart. The growth period of this variety varies with the season, it takes 90- 100 days in summer and 110-130 days in winter, the bud break period is in early April, the first flowering period is in late April, and the full flowering period is mainly concentrated in May and late August, and the flowering period is about 14 days. This variety is resistant to high temperatures, but not to cold. Before planting, it is necessary to apply enough organic fertilizer, strengthen fertilizer and water management after planting, and timely pull the branch and thin the fruit to ensure sufficient sunlight and cultivate more fruiting branches. Fertilization is applied 5-6 times a year, and N∶P2O5∶K2O can be 1∶1∶1 at the young-tree stage, and it is appropriately adjusted to 1.0∶0.5∶2.0 after fruiting. The main pests and diseases of guava are orange fruit flies, aphids and fruit anthracnose, etc., when the fruit size reaches 2.0-2.5 cm, fruit bagging can effectively control the attack by pests and diseases. Chaohong guava has strong growth potential, good fruit commerciality, strong aroma, high quality, strong adaptability, stable yield and some other good characteristics, and is an excellent variety worthy of vigorously advocating cultivation.