Scientists at AgResearch and its subsidiary Grasslanz Technology have been trialling the application of these fungi, which live inside certain plants and can provide protective qualities to the plant, in wheat.
Modern wheat does not naturally host these endophytes, but some wild grass relatives of modern cereal crops do.
The success of selected endophytes in ryegrass has already been well documented, with the commercialised AR37 endophyte strain estimated to contribute $3.6 billion to the economy over the life of its 20-year patent.
“The continued use of synthetic chemicals to protect crops against pests and diseases is becoming a more difficult proposition as concerns mount about risks to human health, as regulations change and as some of these chemicals become less effective,” says senior researcher and Grasslanz Technology chief executive, John Caradus.
“The benefit of selected Epichloë endophytes in ryegrass has gone some way to addressing this challenge of chemical use, and it has also given us insights into opportunities to provide similar protection for wheat and other cereal crops.”
Caradus says when it comes to wheat, there are challenges in introducing suitable endophytes due to issues of genetic compatibility between the endophyte and the host wheat plant.
“However, we have been able to work around that through plant breeding techniques that have given us good matches between the wheat and endophyte.”
In experiments done with wheat containing suitable endophytes, the results seen are quite impressive, he says.
“We have seen improved resistance to infection by Septoria leaf blotch, Fusarium head blight and wheat leaf rust compared with equivalent endophyte-free wheat.
“Improved resistance to insect pests Argentine stem weevil, hessian fly and wheat sheath miner has also been observed in field trials.
“We have evidence in pasture grasses that endophytes can help the plant adapt to some environmental challenges resulting from climate change, and there may be potential for this in cereal crops too, but we are yet to prove this.”
Trials are continuing to better understand and optimise the use of these endophytes in wheat.
Research is also continuing into opportunities to enhance endophytes in ryegrass.
One approach in ryegrass is use of gene editing technology to maximise the protective benefit of the endophyte, while reducing or eliminating the potential toxic effects on animals that can occur in some instances, leading to heat stress or illness such as ryegrass staggers.
“With the use of gene editing, we are seeing that we can address some of those negative impacts in animals from the toxins produced in the plant by the endophyte,” Caradus says.
“Trials of ryegrass containing this gene edited endophyte are underway in Australia, and with change looming to legislation around use of genetic technologies in NZ, we think there could be opportunities in future to carry out trials in NZ.
“If proven to be safe and effective, ultimately we want to see these enhanced endophytes made available to farmers and benefitting NZ.”
NZ is scheduled to host the 11th International Endophyte Symposium in Hamilton in November 2025.
This will be the third time the gathering has been hosted here since these symposia began in 1990.