An endophyte is a fungus found naturally in many grass species, including ryegrass. It provides the plant with protection from insects, and in return the plant provides the endophyte a place to live and reproduce. Endophytes can only be transmitted from one plant to another by seed. New endophyte strains can be introduced into different ryegrass cultivars, but there is no transmission between adult plants growing in pasture.
Endophytes produce a number of chemical compounds, including various alkaloids. The levels and types of alkaloids produced vary between different endophyte strains. Some alkaloids are toxic or deterrent to particular insects (e.g. peramine and lolines), and some can adversely affect animal health (e.g. lolitrem B1) and may depress animal performance when in high concentrations (e.g. ergovaline2). The key is finding an endophyte that provides excellent pest resistance, while at the same time reduces the risk of compromising stock performance.
AR37* is a novel endophyte that produces none of the alkaloids found in other commercially available endophytes. It produces a unique type of alkaloid - janthitrems - which have never been found in any other ryegrass/endophyte combination. These janthitrems seem to play a role in decreasing insect activity (feeding), while having no adverse effect on animal production, though they may in rare situations cause mild and transient ryegrass staggers. Click here to read more about animal health and performance.
AR37 has a number of benefits including improved resistance against insects, livestock performance, and agronomic performance.
AR37 endophyte has been shown to provide superior resistance against a wider range of insects than either pastures containing standard endophyte3 (SE) or pastures containing AR1 endophyte. It provides strong resistance to Argentine stem weevil, porina, pasture mealy bug, root aphid, and black beetle.
For information on the benefits on animal performance and health when using AR37 endophyte click here.
*AR37 is protected by patent in New Zealand.1 Lolitrem B is found in standard endophyte, and is the main cause of ryegrass staggers.2 Ergovaline is produced by standard endophyte, and by some novel endophytes, but levels vary greatly between cultivars.
