Breeding report of a new dwarf banana cultivar Xianfen No. 1 with high resistance to Fusarium oxysporum f. sp. cubense

Xianfen No. 1 is a new banana (Musa nana Lour.) cultivar bred from a natural mutant of Guangfen No. 1 (ABB). A surviving dwarf mutant was identified from a Guangfen No. 1 orchard in Zhongshan in 2016 and then propagated by tissue-culture. From 2017 to 2018, 100 plants were planted in Zhongshan, Jiangmen and Guangzhou, and they harvested from 2018 to February 2019. All plants exhibited dwarf characteristics and high resistance to Fusarium wilt compared with Guangfen No. 1. In 2020, the plants still showed high resistance to Fusarium wilt and then buds were collected to further propagate. By 2023, the incidence rate of Fusarium wilt of nearly 10 000 plants in several places (Guangdong, Guangxi, Hainan, Fujian and Yunnan province) was less than 5%. The comprehensive trait was stable. The height of pseudostem of Xianfen No. 1 plant was 2.09 m, which is over 1 m shorter than that of Guangfen No. 1 plant. The perimeter in bottom and middle of pseudostem were 70 and 48 cm, respectively. The leaf color of Xianfen No. 1 ranged from yellow green to light green. The leaf blade length was 146 cm, the leaf blade width was 47 cm, and the leaf ratio was 3.1. The growth cycle of the new plant was around 11.0-12.5 months, shorten than than that of Guangfen No. 1 and Fenza No. 1. During the flowering period, the fruit axis was relatively short and usually not perpendicular to the ground. The length and girth of the bunch was 42 cm and 87 cm, respectively. The length and girth of the peduncle was 19 cm and 21 cm, respectively. The fruit was short rounded, the length and girth of the fruit was 13.5 cm and 13.2 cm, respectively. The fruit pedicel length was 2 cm. The number of hands was 8 to 12, and the number of fruits of each hand was 12 to 18. The number of fruits was 100 to 135. The average bunch weight was 12.8 kg, the average finger weight was 91 g. The planting density would be180-220 plants per 666.7 m2 and the yield was 2300 kg per 666.7 m2. The mature fruit had a bright yellow skin, thick and easy to peel off. The flesh texture was firm, and the hardness of mature flesh could reach 1.2-1.5 kg·cm-2. The flesh was milky white, and smooth, with moderate sweetness and acidity. The soluble solid content of fruit was 28.30%, the titratable acid content was 4.99 mg·g-1, the total sugar content was 25.30%, the reducing sugar content was 23.30%, and the vitamin C content was 13.60 mg·100 g-1. Xianfen No. 1 had high resistance to Fusarium oxysporum f. sp. cubense race 1, Sigatoka, banana freckle, BBTV and CMV and also had strong wind resistance because of its dwarf pseudostem, but the resistance to cold was weak. It would be suitable for cultivation in the banana producing areas in China with absolute low temperature above 5℃.