Characteristics of the potato variety Chuanyu No. 4

(1) Variety origin: The Crop Research Institute of the Sichuan Academy of Agricultural Sciences used C1an-dia as the female parent and 7XY-1 as the male parent, crossing them in 1991 and selecting through successive generations; the original line number was 5-4.

(2) Characteristics: The rate of large and medium tubers is 67.6%; the starch content of the tubers is 14.22%, comparable to the control Chuanyu 56; the vitamin C content is 10.6 mg/100 g fresh tubers; reducing sugar is 0.53%. According to identification by plant protection departments and in production, it is highly resistant to late blight and virus diseases. The dormancy period is relatively short, about 50 days; the growth period is more than 80 days, making it a mid-season variety. The plants emerge uniformly and grow vigorously; the tubers are round with yellow skin and white flesh. It is a table variety for fresh tuber consumption.

(3) Yield performance: From 1992 to 1994, it participated in the provincial multi-site trial (regarded as equivalent to the provincial regional trial); over 3 years and 21 site-times, the average fresh tuber yield per mu was 1624.9 kg, an increase of 18.8% over the common control virus-free Chuanyu 56, and an increase of 29.0% over the leading local variety. In 1995, in a large-plot production trial at 6 sites within the province, the average fresh tuber yield per mu was 1323.5 kg, an increase of 25.54% over the leading local variety.

(4) Suitable planting areas: It is suitable for planting in the main potato-producing areas of our province on sloped and terraced land and sandy land with deep soil layers, good drainage and permeability, and strong light, and is also suitable for planting in late blight-infested land. In areas below 1000 m elevation, it can be planted in two seasons, spring and autumn.