Breeding and Characteristics of a New Flue-cured Tobacco Variety Yunyan125, with Moderate Resistance to Bacterial Wilt

The new flue-cured tobacco variety Yunyan125, which is moderately resistant to bacterial wilt, was bred with the primary objective of enhancing this resistance, using Oxford 207 (resistant to bacterial wilt) as the paternal parent and Yunyan97 as the maternal parent. This variety was approved by the National Tobacco Variety Approval Committee in 2024. The variety exhibits dark green leaves, vigorous growth, and well-expanded leaves. The average plant height after topping is 113.9 cm, with 19.0 harvestable leaves. The mid-leaves measure 74.1 cm in length and 32.0 cm in width. The stem circumference averages 9.9 cm, with an internode distance of 5.7 cm. The average yield of Yunyan125 is 171.3 kg/(666.7 m²), with an output value of 4995.4 yuan/(666.7 m²). The average price is 29.1 yuan/kg. The proportion of high-grade leaf is 60.4%, and the combined proportion of high- and medium-grade leaf is 91.6%. It exhibits moderate resistance to bacterial wilt, black shank, and root-knot nematode disease. Its resistance level to bacterial wilt is comparable to that of the reference variety K326. In the field, it shows layered yellowing and is easy to cure. The conventional chemical components of the cured tobacco fall within the desirable range, demonstrating well-balanced. Its cured tobacco appearance and sensory quality are comparable to those of Yunyan87. Yunyan125 is well-suited for cultivation in the southwestern tobacco region of China, and is particularly recommended for fields severely affected by bacterial wilt.