广播电视英语短句 第 144 课：食用木薯-5

Irregular yellow spots may appear on lower leaves. 不规则黄点可能会出现在植物低处的叶子上。

But farmers sometimes do not find the disease until they cut open a cassava. 但有时农户直到砍下木薯切开时才可能发现这种病毒。

If there is only a small amount of rot, the dead material can be cut away. 如果木薯上只有小部分腐烂，可以将腐烂的地方去除。

But if the disease has progressed, the whole root is ruined.
但如果病症已经蔓延，整个根都会被毁坏。

Scientists partly blame whiteflies for spreading the disease from plant to plant. 部分的科学家指责是白粉虱在不同的植物上停留而传播了疾病。