AR37 endophyte has been shown to be crucial for maximizing nitrogen efficiency in perennial ryegrass, resulting in economic gains and environmental positives.
DLF Seeds Australian research manager, Martin Harmer, spent four years exploring the nitrogen efficiency benefits of AR37 endophyte and how incorporating it into a pasture system can improve a farmer’s bottom line.
Martin’s research examined the impact of AR37 novel endophyte and its role in increasing nitrogen efficiency on high performing grasses.
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 with a place to live and reproduce.
With a focus on AR37, (an endophyte known for strong insect control resulting in improved pasture production), Martin uncovered its ability to solve other costly problems farmers face, including expensive fertilisers.
Martin recently published a study looking at how farmers can improve nitrogen use efficiency by using AR37 endophyte, whose ability to control insects can increase pasture growth rates and response to applied nitrogen.
His paper is titled Improvement in the nitrogen use efficiency and uptake of perennial ryegrass caused by the Epichole fungal endophyte AR37’; and includes a four-year field trial which evaluated the effects AR37 endophyte has on nitrogen efficiency in high performance ryegrass varieties.
The findings demonstrated pastures inoculated with AR37endophyte had higher production, leading to better forage yields and higher profitability compared to traditional, non-endophytic varieties.
The higher forage yields were evident where one finding demonstrating “AR37 endophyte caused a consistent positive response to nitrogen applied. Where perennial ryegrass withAR37 endophyte, showed a 62.5 per cent increase in dry matter produced per kilogram of nitrogen applied, shown in Figure1” explains Martin.
In addition, Martin found endophyte paired with the right variety, can have an impact on reducing on farm nitrogen costs by using the nitrogen more efficiently, and reduce environmental impacts and nitrogen loss from leaching (e.g. when heavy rainfall washes the nitrogen through the soil profile).
“For farmers, the variety of perennial ryegrass selected and the endophyte it contains will impact both their farm’s profitability and how well their pasture is able to utilise nitrogen to produce feed,” Martin explains.
“Selecting the right ryegrass variety (in this case Base withAR37 endophyte) increases the pasture’s response to nitrogen fertiliser, reducing the amount needed to grow a given amount of feed,” he says.
“Ultimately, you’re producing more feed for the same volume of nitrogen.”
Martin’s research examines how important it is for farmers to choose the right variety of AR37 perennial ryegrass to boost pasture response, with various location and environmental factors having an effect.
“The variety of ryegrass sown profoundly impacts a pastures response to applied nitrogen,” he adds.
“Choosing a variety with the AR37 endophyte significantly boosts pasture yield response, especially during stressful summer and autumn conditions.”
The research was conducted at a farm in Australia using controlled setup. The grass was subjected to five different nitrogen application rates assessed across 22 harvests.
Yield and nitrogen content were measured and the trial was managed under irrigation to simulate optimal growth conditions.
The outcome of this study was that the AR37 endophyte is crucial for maximising nitrogen efficiency in perennial ryegrass, resulting in economic gains and environmental positives.
“The pastures will also respond more vigorously in difficult conditions, such as in autumn,” Martin says.
“Many farmers will be familiar with perennial ryegrass paddocks that appear slow to respond to autumn rains after summer, which can cause an autumn and winter feed deficit.
“By protecting plants from insect pests, AR37 endophyte promotes accelerated growth that’s essential for farmers in difficult times,” he says.
“Improving nitrogen efficiency on farms helps increase farmer profitability by generating more financial output, while also potentially reducing nitrogen losses.”
DLF Seeds has several AR37 products for farmers to sow for autumn; Vast AR37 perennial ryegrass provides strong year-round production with excellent pasture growth during summer and autumn, while Base AR37 perennial ryegrass isa high performance, Australian industry leading variety with high seasonal production, and excellent late quality feed.
Ultimately, adopting perennial ryegrass with endophytes, such as AR37, to achieve higher yields and improved nitrogen efficiency improves a farmer’s sustainability, while increasing the profitability of their land.
