The crust of the bread is burnt.

这块面包的外皮烤焦了。

Oil spotting (oleocellosis) was a prevalent physiological rind disorder of citrus fruits that was caused by the action of phytotoxic rind oils released from the oil cells in the flavedo.

摘要油斑病是发生在柑果实上的一种常见的生理性病害，是由于柑外皮组织中溢出的油的光毒性造成的。