Endophyte

As endophytes (of gr endo = inside; phyton = plant) living beings, usually bacteria or fungi are called who live inside the body of a plant vegetation. While some endophytes cause disease symptoms, others cause no damage and can even in a symbiotic relationship stand by their host plant by producing substances that promote the growth of the plant or increase their stress tolerance. It is believed that this is beneficial for both sides cases are caused by co-evolution of host and settlers from an originally parasitic relationship.

Endophytic fungi

Endophytic fungi in the genus Epichloë ( anamorph and relatives of the genus Neotyphodium ) frequently colonize grasses, in which the fungal mycelium can penetrate the entire stem and leaves. After an infection of the flowers, these fungi are often spread with the seeds of their host plant. For Neotyphodium this is the only form of reproduction and distribution. Infection of neighboring plants only occur in the case of Epichloë. Often these endophytic fungi produce alkaloids that protect plants and fungi from herbivores. In addition, the settlement may make the host plant more resistant to environmental factors such as drought with the fungus, the underlying mechanisms of this protection are still largely unknown.

A well-known example is the pipe fescue ( Festuca arundinacea ), which is colonized by the fungus Neotyphodium coenophialum hose. While non- infected grass is a good pasture forage, livestock shows, the infected eats grass, a number of symptoms ranging from lethargy on reduced growth and lower fertility up to gangrene. For these symptoms are produced by N. coenophialum the ergot alkaloids, especially ergovaline, responsible. Further, produced by N. coenophialum alkaloids, especially Lolinalkaloide and Peramin possess insecticidal properties so that they contribute to the corrosion protection of the grass - endophyte community.

Possible applications for endophytic fungi that are explored are the use for the generation of increased tolerance in crop plants against insect damage and drought, possible with preserved suitability of the plant as animal feed.

Also at least partially inside the plant body and thus endophytic grow numerous wurzelbesiedelnde mycorrhizal fungi. These are found as symbionts with most terrestrial plants and have a positive impact on nutrient uptake and stress tolerance of their hosts. However, they are not usually referred to as endophytes, because a significant portion of the mycelium grows outside of the plant body.

Endophytic bacteria

Different types of endophytic bacteria were detected in several plants. Different bacterial species may be found simultaneously in the same plant, usually single species colonize a particular plant tissue.

In addition to pathogenic bacteria such as Agrobacterium tumefaciens many endophytic bacteria cause no symptoms of disease or even lead to growth-promoting effects. Thus, various types are known to produce the plant hormones which may affect the growth. Of great importance is the provision of nutrients by endophytic bacteria, especially the fixation of nitrogen from the air, the highest developed in the symbiosis between rhizobia and leguminous plants. Also could be demonstrated in some cases that the colonization by endophytic bacteria, the host plant resistant made ​​against attack by pathogens, possibly because the endophytes thought possible action sites already occupied or by the production of antibodies.

Endophytic Kinetoplastea

The Kinetoplastea (also Kinetoplastida ) are a class of unicellular flagellated carrying organisms ( flagellates ); they belong to the Euglenozoa. Many kinetoplast are parasites. The trypanosomatid are a group of unicellular flagellates within the group of Kinetoplastea; ( African sleeping sickness and various diseases caused by the associated species). Some plant pests of the genus Phytomonas among these trypanosomatid.

References and other sources

• Peter H. Raven, Ray F. Evert, Susan E. Eichhorn: Biology of Plants. Walter de Gruyter, Berlin • New York 2000, ISBN 3-11-015462-5
• S. Aldrich - Markham, G. Pirelli and A. M. Craig: endophyte toxin in Grass Seed Fields and Straw - Effects on Livestock, Extension Service, Oregon State University, 1995/2007 (PDF)
• Cindy Lodewyckx, Jaco Vangronsveld, Fiona Porteous, Edward RB Moore, Safieh Taghavi, Max Mezgeay, Daniel van der Lelie1: Endophytic Bacteria and Their Potential Applications. In: Critical Reviews in Plant Sciences. 21 ( 6 ), 2002, pp. 583-606.