| After wheat, maize and rice, potato (Solanum tuberosum L.) became the fourth cultivation crop in the world. In the mid 90's of last century, China's potato cultivation area and production has surpassed EU to become the biggest potato producer. As the most potential cultivated crops on increasing production, in recent years, the industrialization of potato have been paid high attention by the state and local governments. The soil contaminated by heavy metal, not only affect growth and development of potato, but also the heavy metal can enriched in the tubers, resulting in food safety problems in potatoes and their processed products, and export restrictions of the relevant products.In this experiment,10 potato genotypes were used as the materials, seting up four Pb, Cd treatment levels, using two-factor completely randomized experimental design, analysising the effect of yield and quality under Pb, Cd stress and the genotypic differences of Pb, Cd accumulation in potato various parts, Simultaneously, the Pb, Cd accumulation safety of the tested genotypes were evaluated. The results showed that:1. Pb, Cd had a distinct toxicity to potato and significantly reduced the yield. The average individual tuber weight showed significant difference among different Pb, Cd treatment levels. The average individual tuber weight decreased significantly when treatment improving. The number of tuber per plant of potato among the treatments was not significant, indicating that the Pb, Cd concentration in test soil did not affect the potato tubers numbers(single number of strains). Therefore, Pb, Cd mainly impact yield through restraining the size of potato tuber.2. Average individual tuber weight showed significantly negative correlation with Pb, Cd contents of potato various parts. It indicated that the combined effects of Pb, Cd on roots, stems and leaves growth was the reasons to restraining the tuber size. The sensitivity of potatoes on Cd toxicity is much higher than Pb.3. The tuber starch, proteins, soluble sugars and vitamin C were significant differences under Pb,Cd treatment levels, and the genotype, treatment level interaction also reached a significant level. Correlation analysis showed that:tuber dry weight, soluble sugar with stem-leaf Pb-related indexes were (siginificantly) negative correlation, indicating that the increase of Pb content in stem-leaf may lead to photosynthetic system injury and inhibition, further reducing the photosynthetic products.4. Yield, nutritional quality and heavy metal accumulation of different genotypes potatos showed a significant difference under Pb, Cd treatment levels, indicating that different genotypes there were obvious difference in stress response.5. Pb, Cd accumulation in organs of potato had significant differences:under Pb treatment, the enrichment coefficient was root> tuber> stem-leaf, transfer coefficient was tubers> leaves, under Cd treatments, the enrichment coefficient was tuber> root> stem-leaf, transfer coefficient was tubers> leaves.6. The Pb, Cd safety of tested genotypes was evaluated, the results showed that: Despite the genotypes is different, but to a certain level of heavy metal polluted soil, Pb, Cd security risks are obvious. N5-08, N5-10, N5-48, N7-11, S6-X could be used as low-Pb varieties; N5-08, N5-10, N5-47, N5-50, N7-20, S6-4, S6-X, Sy14 could be planted in low Cd contaminated soil as low Cd varieties.7. This article also has a preliminary study on breeding and the application of potato which accumulates low or high heavy metals.
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