Phytophthora nicotianae

Phytophthora nicotianae is a species of oomycete, a group of fungus-like microorganisms, that is known to cause diseases in a wide range of plant species. It is commonly referred to as black shank, a disease that primarily affects tobacco crops.

Taxonomy

Phytophthora nicotianae belongs to the genus Phytophthora, which is part of the Peronosporaceae family. The species was first described by Breda de Haan in 1896. The species name nicotianae refers to its primary host, the tobacco plant (Nicotiana).

Description

Phytophthora nicotianae is a heterothallic species, meaning it requires two different mating types for sexual reproduction. The organism produces sporangia, which are sacs where spores are formed, and oospores, which are thick-walled spores that can survive in harsh conditions.

Hosts and symptoms

While tobacco is the primary host of Phytophthora nicotianae, the pathogen can also infect a variety of other plants, including tomato, eggplant, and pepper crops. Symptoms of infection include wilting, yellowing of leaves, and the development of dark lesions on the stem, often leading to plant death.

Disease management

Management of Phytophthora nicotianae involves a combination of cultural practices, chemical treatments, and the use of resistant varieties. Cultural practices include crop rotation and proper irrigation management to avoid creating conditions that favor the pathogen. Chemical treatments, such as the application of fungicides, can also be used to control the disease.

See also

• Phytophthora infestans
• Phytophthora ramorum
• Phytophthora sojae