农田土壤Nmin对马铃薯块茎形成的影响

为明确农田土壤矿质氮(Nmin)含量对马铃薯块茎形成的影响,在内蒙古阴山北麓马铃薯主产区大田条件下,利用主栽马铃薯品种‘克新1号’,通过设置不同供氮水平,研究了薯田土壤Nmin含量对块茎形成的时间、数量以及重量的影响。结果表明:土壤Nmin含量在18⁵0 mg/kg范围内时均可形成块茎,且在18.6450 mg/kg范围内时均可形成块茎,且在18.64¹9.94 mg/kg可较早形成块茎,超过50.57 mg/kg时,不形成块茎;较高的土壤Nmin含量会降低块茎形成的数量,在内蒙古阴山北麓地区,马铃薯出苗39 d以后,块茎数量不再增加;虽土壤Nmin含量的增加推迟了块茎的形成时间,但较高的土壤Nmin有利于马铃薯生育后期单株块茎重量的增加。

Potato Tuber Formation as Affected by Soil Mineral Nitrogen

In order to test the influence of soil mineral nitrogen （Nm in） content on potato tuber formation, a field trial was conducted in Yinshan mountain, with potato cultivar ＇Kexin 1＇ by setting different nitrogen levels. Field soil Nmin content, tuber formation time, tuber number and weight per plant were measured or recorded dynamically. The results showed that soil Nmin declined with potato development. The soil Nmin content in a range of 18 - 50 mg/kg benefited tuber formation, and the soil Nmin in 18.64 - 19.94 mg/kg was the best level for early tuber formation. When it was more than 50.57 mg/kg, tubers could not form. It also revealed that the higher soil Nmin content could reduce the number of tuber formation, and 39 clays after emergence in Yinshan area tuber number would not increase any more. Although increased soil Nmin postponed the tuber formation, the potato tuber weight per plant increased with soil Nmin.