为明确甜菜重茬的危害，利用多粒、单粒两种类型供试材料，在田间同时进行重茬和生茬比较试验。研究重茬对甜菜产量、品质质量的影响。结果表明：（1）供试的几个多粒种平均减产22429 kg/hm²，单粒种平均减产18354 kg/hm²。（2）多粒种平均含糖下降2.58度，单粒种下降1.36度。（3）K、Na、α-N，多粒种平均分别增加了0.37 mmol/100g、3.31 mmol/100g、1.04 mmol/100g，单粒种分别为0.15 mmol/100g、2.21 mmol/100g、0.39 mmol/100g。（4）重茬地甜菜有害物质含量增加导致甜菜的品质下降，糖份损失率增加，多粒种平均增加0.69，单粒种平均增加0.47；可提取糖率减少，多粒种平均下降3.27，单粒种平均下降2.17；产糖量减少，多粒种减少4996 kg/hm²，单粒种减少3814 kg/hm²。（5）重茬地褐斑病发病早，比生茬地高1~2级。

In order to clarify the harm of continuous cropping on sugar beet, a comparison test of continuous cropping and raw stubble was carried out by using the monogerm seed and the polygerm seed in the field at the same time. The influence of continuous cropping on root quality and yield of sugar beet was studied. The results showed: (1) the average yield of the tested polygerm seed dropped 22429 kg/hm² andthat of the tested monogerm seed dropped 18354 kg/hm²; (2) the average sugar content of polygerm seed dropped 2.58 degree, and that of the monogerm seed dropped 1.36 degree; (3) evenly, K increased 0.37 mmol/100g, Na increased 3.31 mmol/100g and α-N increased 1.04 mmol/100g in the polygerm seed, and K increased 0.15 mmol /100g, Na increased 2.21 mmol/100g and α-N increased 0.39 mmol/100g in the monogerm seed; (4) the increased harmful substance content led to the decline of beet root quality in continuous cropping, and the increase of the sugar loss rate, 0.69 on average for the polygerm seed and0.47 on average for the monogerm seed; extracted sugar decreased, 3.27on average for the polygerm seed and 2.17 on average for the monogerm seed; sugar yield decreased, 4996 kg/hm² for the polygerm seed and 3814 kg/hm² for the monogerm seed; (5) leaf spot disease occurred earlier in continuous cropping than raw stubble, and the disease grade was 1-2 higher than that in raw stubble.