Identification of field cold resistance of new potato variety Guinongshu No.1 planted in winter

ObjectiveUnder continuous low temperature and frost weather,the difference of field cold resistance between the new potato variety Guinongshu No.1 and main cultivar in Guangxi Favorita planted in winter was compared,in order to provide theoretical basis for cold-resistant cultivation and new variety promotion.MethodDuring November,2013-March,2014 and December,2015-April,2016,chilling injury in field of Guinongshu No.1 and Favorita at early period of tuber enlargement and seedling stage after low temperature stress were observed,and effects of chilling injury on yield were investigated.In addition,the soluble protein content,catalase (CAT) activity,superoxide dismutase (SOD) activity and peroxidase(POD) activity in leaf at seedling stage when the seedlings went through low temperature stress were detected.ResultDuring two experiment periods,rainy and frosty days were 76 and 82 days respectively,accounting for 63.9% and 66.9% of four winter months.During seedling stage and early period of tuber enlargement,Guinongshu No.1 suffered less chilling injury than Favorita,and showed stronger cold resistance.At harvest period in 2014,the yield of Guinongshu No.1 was 19.0% higher than that of Favorita,and 61.0% higher in 2016.Soluble protein content,CAT activity,SOD activity and POD activity in leaves of Guinongshu NO.1 were significantly higher than those of Favorita on the fifth day after low temperature stress(P<0.05).Conclusion Guinongshu No.1 has strong cold resistance and high yield under continuous cold and frost weather.Therefore,it has promising application potential in the winter potato planting area in China.