Breeding report of a new large fruit longan cultivar Liangyuan Longyan

Abstract: Liangyuan Longyan is a new variety of longan (Dimocarpns longan Lour.) selected from a crossing between Dawuyuan (large fruit) and Chuliang (high quality) made in April, 2005 by the Institute of Fruit Tree Rearch, Guangdong Academy of Agricultural Sciences. The SSR molecular analysis confirmed that it is a hybirid of Dawuyuan and Chuliang. The hybrid seedlings were obtained in 2006, and the hybrid trees started flowering and bearing fruit successively from 2013. One of the hybrid trees exhibited excellent fruit characteristics in 2014. Over seven consecutive years from 2015 to 2021, the fruit quality and fertility of the strain were evaluated in comparison with its male and female parents. It was approved by the Crop Variety Approval Committee of Guangdong Province and named Liangyuan Longan (Yuepingguo 20220006) in March 2023. The tree of Liangyuan Longyan was erect and vigorous with a round canopy. The trunk was gray- brown, with rough bark and moderately pronounced cracks. The leaves were pinnate compound, with opposite leaflets mostly in 4-5 pairs, occasionally 6 pairs. The leaflets were elongated oval in shape, long in length, slightly curled upwards, thick, with wrinkles on the leaf surface, and short wedge-shaped leaf bases, and deep green in color. The burst period of the top buds of Liangyuan Longan was in mid to late January, and the sprouting period of the flower clusters in early February. The initial flowering period was from early to mid-March to early to mid-April, varying significantly in different years. The peak flowering period was from late March to mid-April, and the flower shedding period was in late April. The flowering period of a single tree was approximately 20-30 days, while that of a single spike was 10-20 days. The flowers were in conicalclusters, large in size, with a yellow-green axis, and moderately deep-cleft stigma heads. The fruits matured from the end of July to mid-August. The fruit clusters were well- formed, with uniformly sized fruits weighing 13-18 g each. The fruit skin was yellowish-brown, presenting a good appearance. The flesh was milky white, slightly translucent, with prominent longitudinal wrinkles on the surface. The fruits did not exude juice, and the juice content was moderate. The flesh was easily separated from the seed, chewy and slightly fibrous, with a sweet taste. The edible rate was 64%-69%, and the soluble solids content was 19%-21%. Compared with the male parent Chuliang, the fruits were larger, and compared with the female parent variety Daguanyuan, the fruit quality was much better. The seedswere flatround, with medium-sized seed hilums. The ripening period in the Guangzhou region was from late July to mid-August. It had moderate productivity. It would be suitable for cultivation in various production areas in Guangdong Province.