陕西蚕病流行规律分析

通过历年盒种产茧量、干茧病蛹及蚕期蚕病调查，得知养蚕技术、养蚕形式、地理位置、气候条件影响陕西蚕病的流行分布。近几年危害生产的主要是僵病、多角体病及微粒子病。各地由于养蚕形式、技术、地理及气候差异，蚕病发生轻重不同。僵病流行比其它蚕病受养蚕技术、地理、气候影响更明显。多角体病流行与僵病不同，有较明显的垂直传播特点。微粒子病自１９８９年发现之后，蔓延迅速，其病原首先来自从疫区调入的带毒蚕种。

ANALYSIS ON SITUATION OF SILKWORM DISEASE EPIDEMIC IN SHAANXI

According to the investigation on cocoon outputs,on sikworm diseases occurring indifferent rearing seasons and on diseased pupae in dried cocoons over the years,it isunderstood that the rearing type and technique,geographical and climatic conditionsinfluence the epidemic of silkworm diseases in Shaanxi.In recent vears,the diseasescausing loss in production have been mainly muscardine,polyhedrosis and pebrine.Degree of the occurrence varied in different places due to difference in rearing types andtechniques and geographical and climatic conditions.The epidemic of muscardine wasmore obviously influenced by those factors than other diseases.That of polyhedrosis wasdifferent with muscardine.It had more obvious characteristic of vertical transmission.Pebrine has spread rapidly since 1989 when it was firstly discovered.The pathogen wasfrom the eggs introduced from the diseased region.