施氮量对炸条型马铃薯产量及叶面积的影响

Effects of Different Nitrogen Rates on Yield and Leaf Area of French Fry Potato

以炸条型马铃薯品种‘抗疫白’（Kennebec）为供试材料，设计6个施氮水平，通过田间小区试验，研究不同施氮量对马铃薯产量和叶面积指数的影响。施氮量与马铃薯产量的关系用二次函数拟合效果良好，方程为y=-0.0012x^2＋0.3717x＋18.6720，对方程求导，当施氮量达到154.8 kg/hm^2时产量达到了最大值47.5 t/hm^2。不同时期的叶面积指数与产量的关系用二次方程拟合效果良好，对方程求导，获得的叶面积指数适宜的范围，出苗后20，30，40，50，60，70，80和90 d的叶面积指数依次为2.35-2.62,2.84-3.20,4.19-4.66,5.23-5.60,4.31-5.04,4.29-4.96,3.53-4.10和2.78-3.42。

French fry potato ＇Kennebec＇ was fertilized at six nitrogen rates in a plot experiment, and the effects of different nitrogen rates on potato yield and leaf area index were studied. With the increase of nitrogen rate, the yield of ＆#39;Kennebec＆#39; increased at first and then decreased, and the relation of nitrogen rate and potato tuber yield could be described by a quadratic function, y=-0.0012x^2＋0.3717x＋18.6720. The yield of ＇Kennebec＇ reached 47.5 t/ha of maximum value, when the nitrogen rate was at 154.8 kg/ha. The relation of leaf area index and potato tuber yield could also be described by quadratic function, with the optimal ranges of leaf area index were 2.35-2.62, 2.84-3.20, 4.19-4.66, 5.23-5.60, 4.31-5.04, 4.29-4.96, 3.53-4.10 and 2.78-3.42 for 20, 30, 40, 50, 60, 70, 80 and 90 days after the emergence, respectively.