Medium-maturing variety with about 110 days of growth period (seeding to harvest)

乐发ll　　The plant type is spreading. The plant height is 60~70cm. The stem is green and the compound leaf is thick and large.

　　The corolla is pale purple. The pistil and stamen are aborted, without natural fruiting. The tuber is elliptic, large and evenly. The smooth skin and the meat is white. The bud eye depth is medium. The tuberization is concentrated. The tuber has a long dormant period and is resistant to storage.

乐发ll　　The plant is resistant to late blight and tuber susceptible, immune to ring rot, resistant to potato X virus and Y virus, highly resistant to potato leaf roll virus and tolerant to Potato Spindle Tuber Viroid (PSTVd). The root system is developed, with very strong drought resistance. It is also resistant to storage. With a strong yielding ability, it can reach 2000~2500kg/mu generally, and 3500kg in high yield. With an extensive adaptability, this variety is mainly distributed in Heilongjiang, Jilin, Liaoning, Inner Mongolia, Shanxi, and Ningxia, etc. It also cultivated in the Central Plains with Two -time Crops, like Shandong, Anhui, Zhejiang and Shanghai, etc. Generally, the planting density is 3500~4000 plants/mu.