The Influence Of Soil Nitrogen Amount On Potato Tuber Formation

To clear the effects of mineral nitrogen (Nmin) in soil on potato tuber formation, cultivar Kexin No.1popular at local area was used for investigation. Both pot and field experiments were performed at the north foot of Yinshan Mountain, Inner Mongolia in the year2012and2013. The relationship between soil Nmin and tuber formation time, tuber number, plant biomass, leaf area index and tuber yield was investigated in this study. The major conclusions are showed as follows:(1) The timing of potato tuberization is affected significantly by soil Nmin. With the increase of soil Nmin potato tuberization is retarded, as the value of soil Nmin is higher than39.29mg/kg at the tuberization stage it is inhibited at the north foot of Yinshan Mountain, Inner Mongolia.(2) The tuber number of potato is affected significantly by soil Nmin. There is no tuber forms as the value of soil Nmin is over than51.14mg/kg; More than four tubers produce as the value of soil Nmin locates between18.79-31.83mg/kg at the north foot of Yinshan Mountain, Inner Mongolia.(3) Under the certain total nitrogen fertilizer applied condition, decreasing basal fertilizer and increasing top dressing is not only beneficial for potato tuberization, increase tuber number, but also for maintaining higher leaf area during developmental stage, obtains high yield finally.