甜菜枯萎病及防治研究

STUDIES ON SUGARBEET PHOSPHORIC DEFICIENCY WILT AND CONTROL

从甜菜根和叶上分离的各种真菌、细菌进行人工接种,以病叶汁液磨擦接种,均未重复出现田间枯萎植株。分析甜菜病、健植株磷的含量,健株比病株高出2倍以上。测试健株土壤含磷量比病株土壤高出5倍。病株土壤经蒸气或高压灭菌后土壤里有效磷比未灭菌土壤明显地高,生长的甜菜健旺。在缺磷培养液里生长的甜菜重复出现田间枯萎症状,可见甜菜枯萎病是缺磷引起的一种新的生理病害。1979—1981年小区试验施磷肥区防治缺磷枯萎病效果显著,单施氮肥加重病情。1982—1987年在双辽、德惠、农安和怀德等县,每亩施磷酸二铵10—20公斤,或过磷酸钙57—75公斤作种肥或底肥大面积防治13万亩,防效为70—95%,增产30—300%,增糖0.8—4度。

Varied fungi and bacteria were isolated from the leaves and rootsof sugarbeet,and were inoculated on sugarbeet artificially,and alsoused the juice of diseased leaves by rupping inoculation on sugarbeet,but no symptoms were produced in the field. Both diseased and healthy beet plants were analysed for thier con- tent of phosphorus,the latter is 2 times higher than the former.Thesoil phosphoric contents of healthy plants is 5 times higher than thatof soil around the diseased plants.The soil around the diseased plantwhen sterilized by steams or autoclaves,its avilable phosphoric levelis higher than the untreated soil,and the plant grew well.When the beet plants grown in phosphoric deficiency solution,the symptoms ofwilt again appeared as same as in the field,We suggested that this isa new physiological disease caused by the deficiency of phosphorus,it is not an infection disease caused by pathogens.In 1978—1981 we have carried out a test in some plots by using phosphoric fertilizer to control the wilt disease,we have got very goodresults,but if used nitrogen only,the wilt disease could be increased.In 1982—1987,130,000 mu of experimental fields were added with 10—20 kg of(NH_4)_2P_2O_5 or 57—75kg of superphosphate per mu as seed manureor basic manure during sowing time in Shuangliao,Dehui,Nonan andHuaide Counties the efficiency of disease control was at 70—95%,theyield was increased 30—300%,the sugar content by 0.8—4 degree.This control method is evently simple,effective and economic.