Hastings, New Zealand
July 27, 2010

Farmers’ increasing protest at the lack of persistence in new pasture cultivars is justified when a ryegrass sold as a perennial begins to die away in its third year, says Germinal Seeds NZ Ltd general manager David Kerr.

"Farmers are saying the new grasses don’t last like the old varieties and I agree that it appears some seed companies have tried to further increase drymatter yield for a marketing edge but have not managed to retain those persistency traits,” said Mr Kerr.

"Now farmers are being advised on how to better manage the more fragile pastures but really they don’t want to be farming on eggshells; they want a grass that will last.”

Mr Kerr said Germinal’s high sugar grasses are proven to be reliable and are the result of a 30 year programme of recurrent selection within two restricted breeding populations where the focus is on herbage quality, drymatter yield and high levels of persistency.

He recently visited a sheep and beef farm near Dargaville where AberDart is seven years old and despite Northland’s climate, kikuyu and insect challenges the AberHSG (high sugar grass) pastures at Paddyvale Stud have grown strongly through a third consecutive drought.

“I also saw AberDart growing on Awaroa Farm at Waikaretu (south of Pukekohe) and it continues to recover strongly from intensive grazing while another perennial ryegrass, sown at the same time three years ago, is already showing large dead areas and will likely need resowing.”

Mr Kerr said the AberHSGs’ dense roots and numerous tillers were the product of breeding for persistency against frost, heat, drought, UV light, numerous fungal, viral and bacterial pathogens, a wide range of invertebrate pests and hard grazing.

He said there is a trend in New Zealand to promote fungal endophytes, embedded in the seed, as a way to enable pasture persistence because it deters grub and insect attack but the focus has to be on breeding strong and dense grasses that will endure the tough times.

“Insect challenges are a problem, as are droughts and winter pugging, but these are the conditions that exist from season to season and it’s essential for grasses to have strong roots and the ability to bounce back,” said Mr Kerr.

Ryegrass persistency was “not an easy quality” because it relates to the adequate growth of new tillers and roots as well as the production of proteins and other metabolites to naturally protect against damage.

“It requires long term trials and long term investment in the research,” said Mr Kerr

“If selection was for yield alone there would be a tendency to divert plant assimilates produced by photosynthesis away from the many different metabolic pathways required to maintain persistency.”
He said one way to foster an overall increase in pasture quality is to introduce independent grass testing, as done in the UK by the National Institute of Agricultural Botany (NIAB).

It claims to have prompted an advance in grass breeding over the past 12 years in the UK that has increased overall yield by 5% and digestibility by 2%, and led to an equivalent 10% rise in animal output.

NIAB tests for forage digestibility, grazing value and ground cover as well as drymatter yield at different times of the year, seed heading date and crown rust and mildew resistance.

Caption: David Kerr, of Germinal Seeds NZ Ltd, walks through AberDart and clover flourishing at high altitude at Nimrod Downs, South Canterbury.
 

Website: http://www.germinalseeds.co.nz/

Published: July 27, 2010