Aflatoxin pollution has always been a major threat in peanut production, storage and processing in China, especially in the Yangtze River delta and southern China where bacterial wilt, another important disease of peanut, is prevalent. Although the genetic improvement is one of the fundamental ways to prevent the pollution, commercialized resistant varieties are rarely released in the international market. 

Researchers at Oil Crops Research Institute, CAAS took the lead in developing genetically improved varieties of aflatoxin resistant peanut. By the development of systematic rapid screening method and molecular marker-assisted selection technology, they have for the first time proved the potential of synergic improvement of aflatoxin resistance and other major traits of the crop. Through cross breeding and genetic recombination, they equipped the crop with attractive traits which is not only resistant to aflatoxin and bacterial wilt but also rich in oil content. Zhonghua No.6 is the most representative variety created. It’s a pearl-like early mature peanut variety suitable for cooking and oil extraction. It was indicated that under lab conditions, its aflatoxin content is only 10% of the control group, tops all the existing varieties in aflatoxin resistance. Moreover, its bacterial wilt resistance rate is as high as 93.9%. Zhonghua No.6 has been commercialized in six provinces in China, reaching 800 thousand hectares and creating 1.9 billion yuan economic returns since 2001.