Introduction and Cultivation Points of the Su Shu No. 7 Sweet Potato Variety

Su Shu No. 7 (Xu 54-1): It was bred in 1996 by the Xuzhou Sweet Potato Research Center in Jiangsu through sexual hybridization using Ji Shu No. 10 as the female parent and ais0122-2 as the male parent. From 1992 to 1996, the results of 33 trial sites showed an average yield of 2181.4 kg per mu, an increase of 18.2% over the control Xu Shu No. 18, and an increase of 15.5% in dried sweet potato. The fresh sweet potato yield per mu was 2300 kg-2500 kg.

Characteristics: the top leaves are green, the leaves are heart-shaped, the veins are purple, and the stem color is green with purple; the vines are medium-long, with 5-7 branches, and strong growth vigor; the sweet potato skin is red and smooth, the flesh is white, the tubers are spindle-shaped, and the dry matter rate is 29.9%; tuber formation is uniform, with 4-5 tubers per plant, a high rate of marketable tubers, rapid tuber enlargement, and strong late-season performance; good sprouting ability, fast and abundant sprout emergence, strong seedlings, and a large amount of cuttings harvested. It is highly resistant to root rot and stem nematode, susceptible to black spot disease, and has strong drought tolerance.

Cultivation points: cultivate strong seedlings of the appropriate age, control the seeding rate at about 18 kg per sq m, and promptly transplant seedlings of sufficient age into the cutting nursery; apply fertilizer rationally, combine nitrogen and phosphorus in the base fertilizer, control topdressing, and prevent excessive vegetative growth; suitable for planting in mountainous areas and early fields, while field drainage should be done well in plains and low-lying areas to drain waterlogging and remove waterlogging damage; suitable for planting in areas with root rot and stem nematode.