摘 要：
1958年在前信宜县金垌乡金星高級农业社进行了大面积的防治甘薯瘟試驗。防治措施主要是:(1)用无病薯块育苗。品种为最易感病的当地丰产良种“黑节降”,比較抗病的“选二”和很少量的抗病品种“台农46号”,以后在定植时由于种苗缺少一些,曾从农家无病田里剪取一些“新洲薯”(中等抗病)及“木薯”(很抗病)的切条来补充。(2) 育苗地和假植地都选用与水稻轮栽过一年至多年的田块,定植地(即大田)則用种过水稻半年以上的田块。在試驗过程中尽可能采取了避免污染的措施。本試驗的結果是显著的。薯块育苗地完全沒有发病,在12片假植田中只有2片各有几条苗发病,在68片大田中只有15片发病,发病率一般为0.1—0.5%。但对照区却严重发病(假植地发病率为2—40%,大田发病率一般为20—30%,严重的达100%)。試驗結果表明甘薯田土壤中的病原菌在水浸半年后可能全部死灭。經1957年試驗証明抗病性強而貭量較好的品种“台农46号”推广到高州县历年严重发病的金垌、池垌和北界三个乡去,种植了約200多亩,也完全沒有发病。
译 名：
FIELD CONTROL OF BACTERIAL WILT OF SWEET POTATO
作 者：
H. C. FAAN (South China Agricultural College) L. K. CHOU (Kwangtung Agricultural Research Institute) H. M. LEUNG (Agricultural Bureau of Kao-chou District)
摘 要：
A wilt disease of sweet potato caused by a species of bacteria inflicts serious losses in many districts in western, central and eastern parts of Kwangtung province. The identification of the pathogen is in progress. It is believed that the disease is the same as that described by Hwang et al (1956, Acta Phytopathologica Sinica 2 (2): 97—113) in Kwangsi district. The disease is chiefly transmitted by affected cuttings and seed potatoes as well as by infested soils. It is particularly serious in those fields where continuous cropping of sweet potato is practiced. The severity of losses is generally greatly reduced if the preceding crop is rice or water-taro grown under continuous flooding for several months or longer. Sweet potato varieties grown in Kwangtung vary in their resistence as expected, the most productive varieties being in general the most susceptible. In the spring of 1958 a large scale control experiment was conducted in 70 Mou (亩) of water rice land in western Kwangtung where the disease was historically serious. The control measures consisted in: (1) Using healthy seed tubers selected from disease-free fields or disease-free localities for propagating nursery vines. To assure that the seed tubers were free from infection, the tubers were cut at both ends for examination. Diseased tubers when found were discarded and healthy ones subsequently disinfested in 0.1% HgCl_2 solution for 10 minutes. (2) Selecting fields which previously had been under water rice cultivation for half a year or longer for planting as well as for growing seed tubers for propagating nursery vines. (3) Avoiding possible contamination of seed-bed soils and field soils. Possitive results of control were obtained. All the seedlings grown from the tubers were free from infection. Only rarely were the nursery vines grown from the seedling cuttings infected. In the nearby propagating beds (which serve as control) the nursery vines were moderately to seriously infected, the percentage of infection being from 2 to 40. In the 68 experimental field plots planted to sweet potatoes with disease free vines covering a total area of 70 Mou, only 15 plots showed slight degree of infection, the infection rates generally ranging from 0.1 to 0.5%. Among the 41 control plots distributed in 2 localities covering about 27 Mou, 37 plots were infected to various degree, the infection rates ranging from to 1 to 100% with an average of about 30%. A variety of sweet potato, Tai-Nung No. 46, was found to be highly resistant to the disease. It is recommended to be grown in high land areas where the disease cannot be controlled by the measures described above.
