Heat injury - High temperatures are
also very injurious to perishable
products. In growing plants,
transpiration is vital to maintaining
optimal growth temperatures. Organs
removed from the plant, however, lack
the protective effects of transpiration,
and direct sources of heat, for example
full sunlight, can rapidly heat tissues to
above the thermal death point of their
cells, leading to localized bleaching or
necrosis (sunburn or sunscald) or
general collapse.