Effect Of Foliar Application Of Sodium Selenite On Quality And Yielid Of Colorful Potatoes

Selenium is one of the essential nutrients in the human body.Selenium enriched food is regarded as the most reasonable and effective wayfor selenium supplement. The current research foucs on selenium accumulation in anthocyaninshighly enriched colored-flesh potato by exogenous selenium application. The selenium contents, quality and yield of ten colored-flesh potato varieties were investigated by spraying different concentration of sodium selenite in tuber formation stage(CK: 0 mg·L-1,T1: 40 mg·L-1,T2: 80 mg·L-1,T3: 120 mg·L-1).The results are shown below:1. The selenium contents of different colored potatoeswere significantly improved and accumulatedby spraying sodium selenite. Without sodium selenite application,the selenium contents of different colored potatoes were 0.15~0.25mg·kg-1. The selenium contents of different colored potato varieties were 0.18~0.37mg·kg-1, 0.26~0.43mg·kg-1,0.35~0.63mg·kg-1in T1, T2 and T3 treatment, and increased by 10.98~80%, 47.88~109.13% and 92.01 ~184.23% respectively compared with CK. White-fleshed varieties Shepody and Kexin 1,purple-fleshed varieties CQB1540 and CQB1508 were the best at accumulating selenium,CQP1505 followed.2. By analyzing the factor of yield components and yield, spraying sodium selenite of different colored potatoes had non-significant effect on commodity potato rate. However, it affected average tuber weight per plant and yield observably, thereinto, the T2(80 mg·L-1)treatment presented better influence. With the increase of solium selenite dosage, the variation of average tuber weight per plant and yield increase first and then decrease. Kexin No. 1revealed the best character under all of the treatments, followed by purple-fleshed varieties CQP1505, CQB1540 and CQB1508. On the contrary, red-fleshed varieties CQR1501 was the worst.3. Spraying sodium selenite could improve the tuber quality of different colored potatoes,of which T2(80 mg·L-1) treatment was better. Contents of starch and soluble protein could be improved by spraying sodium selenite with low concentration(80 mg·L-1) while dry matter contents decreased slightly but not significantly. Unfortunately, they all of them were inhibited by spraying higher concentration(120 mg·L-1) of sodium selenite. Purple-fleshedvarieties CQP1505, CQB1540, CQB1508 and Heimeiren presented better under T2(80mg·L-1)treatment than other colored potatoes.4. Accompanying with the increase of solium selenite dosage, the trend of total phenolics contents rose initially and then decreased. The anthocyanin contents showed a trend of decline indistinctively. The trend of antioxidant activity showed increase after the first decrease and then decrease. On the whole, all varieties reflected better under T2(80 mg·L-1)treatment than others. Compared with CK in T2(80 mg·L-1)treatments, total phenolics contents of different coloar potato varieties increased 1.80~14.22%, anthocyanin contents increased-11.18~21.10%, antioxidant activity increased 0.22~17.71%. The total phenolics contents,anthocyanin contents and antioxidant activity of purple-fleshed varieties CQP1505, CQB1540 and Heimeiren were higher than other varieties, white-fleshed varieties Shepody and Kexin1 and yellow-fleshed varieties Favorita were the lowest.Therefore, the result showed that spraying sodium selenite could improve the tuber selenium contents of different colored potatoes, make them reach the standard of selenium-rich, increase the yield and improve the quality. According to the study, it can provide a relatively complete reference and technical support for research in colored-flesh potato with selenium-rich in future. The colored potato variaties CQB1508, CQB1540 and CQP1505 and genaral potato variaties Kexin 1 were recommended as selenium enriched varieties.