AR37 ENDOPHYTE IS YOUR KEY TO BETTER
PASTURE PERSISTENCE AND PRODUCTIVITY.
AR37 endophyte, developed by AgResearch Grasslands and commercial partners, takes pasture pest resistance to a new level. AR37 provides resistance against five of the main pasture pests in New Zealand pastures (Argentine Stem Weevil, Pasture Mealy Bug, Root Aphid, Black Beetle and Porina. Note: In pastures with AR37 ryegrass, Porina can be present and feed on the other pasture mix components. Early field trial results have confirmed laboratory evidence of resistance of ryegrass with AR37 to Porina.
Ryegrass with AR37 has better persistence; and yields on average 12% more drymatter nationally than the same cultivar with standard endophyte. AgResearch trials over three years in four locations produced an average of 12% more drymatter nationally from a ryegrass with AR37 compared to the same cultivar with standard endophyte.
To visit the AR37 website click here
Overall Conclusions of the DairyNZ Trial after 3 years.
A dairy trial run by DairyNZ had the following conclusions after 3 years:
AR37 ryegrass was clearly more persistent than either AR1 or standard (HE) ryegrass. This supports findings from previous work. The greater persistency translated into a reduced need for renovation of AR37 pastures after the 2008 drought, but in the three years before that time there was no difference in total pasture yield. There was no sign of ryegrass staggers or any other animal health issues in cows grazing AR1 or AR37 pastures - even at times when cows grazing HE were affected by ryegrass staggers. There was a trend for slightly lower milksolids (MS) production over summer/autumn from cows grazing AR37 or HE compared with AR1. Where ryegrass persistence is the top priority then AR37 will clearly deliver benefits. Where persistence of AR1 ryegrasses is not a problem, continuing to sow AR1 is advised. DairyNZ can not envisage any situation in which farmers should sow Standard (HE) ryegrass.
AR37 pasture (right) showing persistence over the same variety with Nil endophyte (left) at
the DairyNZ trial in the Waikato during the drought early in 2008.
SOURCE: Dairynewz, Summer 2008.
Animal Health
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. To date no ryegrass staggers have been reported on dairy cows grazing AR37 ryegrass. Due to the fact that no trial work has been undertaken on deer and horses, pastures with AR37 are not currently recommended for these livestock classes.
Animal health problems caused by endophyte can be reduced by adjusting summer/autumn grazing management. Hard grazing to the base of pastures containing Lolitrem B and/or Ergovaline will increase the likelihood of endophyte related animal health problems.