Every kind of plant,such as disease germ,harmful insects,weed and so on distribute on certain geographic scope,but it may spread to far place and expand distribution. 各种植物病原菌、害虫、 杂草等都 带有一定的地理分布范围，但也有 远距离传播和扩大分布的可能
Every kind of plant, such as disease germ, harmful insects , weed and so on distribute on certain geographic scope, but it may spread to far place and expand distribution. 各种植物病原菌、害虫、杂草等都 带有一定的地理分布范围，但也有 远距离传播和扩大分布的可能
There are two ways to diffuse.One is natural difffusion and the other is art- ificial diffusion.The latter is mainly through plant especically seed and nursery),plant product besides its pa- cking and conveyance 它们的传播主要有自然 传播和人为传播两种途 径。后者主要是通过植 物（尤其是种子和苗 木)、植物产品及其包 装、运输工具。 检疫 QUARANTINE
它们的传播主要有自然 传播和人为传播两种途 径。后者主要是通过植 物（尤其是种子和苗 木）、植物产品及其包 装、运输工具。 There are two ways to diffuse. One is natural difffusion and the other is artificial diffusion. The latter is mainly through plant ( especically seed and nursery), plant product besides its packing and conveyance
These insects which are carrying disease often are restrained by natural enemy,plan resistan- ce and agricultural production system which forms for a long time in producing area and people pay no attention on them which occur and damage.But if the environment is suitab- le and the place lacks of corresponding effecti- ve preventing and controlling measure,they often explode in the short time and bring disa- ster once they spread around new area
These insects which are carrying disease often are restrained by natural enemy, plan resistance and agricultural production system which forms for a long time in producing area and people pay no attention on them which occur and damage . But if the environment is suitable and the place lacks of corresponding effective preventing and controlling measure , they often explode in the short time and bring disaster once they spread around new area
!奎今为止，数 I ,使我国经济遭 了无可计量的
!!!至今为止,数 以万计的害虫入 侵,使我国经济遭 受了无可计量的 损失
美洲斑潜蝇 白蚁 兵蚁 有翅蚁 小楹白蚁
美洲斑潜蝇 小楹白蚁