Sweet potato is an important root crop both for food and bioenergy, and it is also the first candidate for food reservoir and healthy diet in China. In past decades, the traditional breeding of sweet potato in China has been sluggish compared with other major crops due to its biological characteristics of hexaploid genome, self-incompatibility, and severe segregation in crossed progenies. To speed up sweet potato molecular breeding, Prof. Zhang Peng and his team have been collaborated with partners from Tai’an Academy of Agricultural Sciences since 2005 to carry out several projects on sweet potato genetic improvement. Recently, the joint team won the 3rd-place prize of Shandong Science and Technology Progress Award in 2019 based on their application “Technological innovation on sweet potato breeding and breeding new cultivars of Taizhong series”. Prof. Zhang is the first author of the award and SIBS is the second listed institute.

The program aimed to solve the problems of sweet potato breeding and cultivation, including the low rate of sweet potato flowering in northern China, self-incompatibility, lack of elite varieties, and mismatch between cultivar and cultivation method. To reach the objective, a technological system was established by integrating breeding, variety, yield and quality, cultivation, and application. Using the improved flowering and fruiting technique, the team bred and released several new varieties, including edible cultivar “Taizhong 6”, starch-type cultivar “Taizhong 9” and purple-fleshed cultivar “Taizhong 11”; all these cultivars have been passed through the national or provincial accreditation and in aggregate cultivated for about 6.82 million Mu with economic gain of 2.88 billion RMB. In collaborate with colleagues from Max Planck institutes, the team published the work of whole genome sequencing of sweet potato “Taizhong 6”and its hexaploidization history in Nature Plants in 2017. In 2019, the research team also reported the first case study of genome editing in sweet potato for starch improvement.

The achievement assembles integrative sweet potato breeding technologies in China and reflects the advantages of cooperation between the Chinese Academy of Sciences and the local Academy of Agricultural Sciences, by jointly establishing sweet potato molecular breeding and new varieties demo bases, realizing technology and germplasm innovation, forming a core intellectual property with new varieties, patents and research papers. The program results in a rapid application and promotion of sweet potato new technologies, which assists agricultural restructuring and services. Key members including Dr. Wang Hongxia from SCCB and Dr. Yang Jun from Chenshan Plant Research Center together with graduate students participated in the whole program. The program was supported by grants from Chinese Academy of Sciences, Ministry of Science and Technology and National Science Foundation of China.