河北省卢龙县果农在实践中发现使用医用四环素药片防治梨黑星病有奇效。每年只需用药1次,即可有效地预防梨黑星病的发生。此法可使好果率达90％以上,好叶率达95％左右。 具体作法如下: 首先把医用四环素药片研磨成粉末,然后加水调成糊状,于5月中下旬结合环剥进行施用,环剥 Lulong County, Hebei Province, farmers in practice found that the use of medical tetracycline pills pear scab control miraculous. Just once a year medication, you can effectively prevent the occurrence of pear scab. This method can make good fruit rate of more than 90%, good leaf rate of about 95%. Specific practices are as follows: First, medical tetracycline tablets ground into powder, and then add water into a paste, in late May combined with girdling application, girdling