Stress metabolites of phytoalexins

Plant under the stress by disease microorganisms produce stress metabolites, known as phytoalexins, which provide a natural defines.

Phytoalexins is special class of stress metabolites, i.e substance which have an implicit role in disease resistance.

Various invading organisms such as bacteria, verses fungi and nematodes will induce the reduction of phytoalexins in plants. In addition, exposure to cold, ultraviolet light, physical damage, and certain chemical compounds such as metal slats, polyamines, and certain pesticides can elicit the production of phytoalexins.

Phytoalexins are usually elicited locally at the site of attack. Some evidence exists for accumulation of phytoalexins in edible tissue, particularly in potatoes and sweet potatoes. The classic example of phytoalexin production occurs in potatoes inoculated with the blight fungus, Phytophthora infestans.

When inoculated into the potato, certain strains of this fungus will initially grow rapidly, followed by gradual slowing of growth.

Some phytoalexins have been demonstrated to be toxic to humans. Generally stress metabolises possess some degree of toxicity to living matter and given that this toxicity can be extended t humans, one must consider there importance in the context of human and livestock safety.
Stress metabolites of phytoalexins