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Who should use AR37?
Farmers who want improved pasture production, persistence and animal performance from their pastures should use AR37, especially where damaging insects are likely to be present. Trials that have been undertaken show that AR37 is a suitable pasture for dairy cows, sheep, and beef animals. Pastures with AR37 have their largest differences in drymatter results compared to the same cultivar with standard endophyte in regions from Taupo north. These regions normally experience severe insect pressure.
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How long has AR37 been around for?
AgResearch together with its commercial partners began work on developing the AR37 endophyte in 1995. AR37 ryegrasses were released commercially in autumn 2007.
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Which ryegrass cultivars have AR37?
AR37 will be available in a range of ryegrass cultivars from Agricom and PGG Wrightson Seeds. To find out what will work best for you, contact:
Agricom on 0800 183 358
PGG Wrightson Seeds on 0800 805 505
Commercial cultivars available with AR37 endophyte:
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How should pasture with AR37 be established?
As with new AR1 pastures, all existing ryegrass plants should be removed from the paddock (using spraying and/or ploughing), and old ryegrass seed buried or germinated (following multiple spray applications or cropping) before planting ryegrass with AR37. Re-establishment of old ryegrass plants will not result in failure but can reduce animal performance (if old ryegrass has standard endophyte), pasture production and possibly persistence.
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AR37 is not the perfect endophyte - so what is?
At the moment AR37 endophyte provides much better drymatter production and persistence than any other commercially available endophyte. Although AR37 does not produce lolitrem B it can cause ryegrass staggers. Trials have shown that on average the frequency, duration and severity of ryegrass staggers is less than for standard endophyte. However on occasions, sheep (and potentially other animals) grazing AR37 ryegrass may be severely affected for short periods. There is a risk with staggers, but it is believed the benefits far outweigh this one risk. The question is, does the perfect endophyte actually exist? Research is ongoing and until such a discovery is found, there will always be some compromise.