17 October 1984 Turf retardant research could lead to better pasture grasses

Mowing the lawns around the house could stop being a weekly chore when a turf retardant now being developed overseas is released for sale to the home gardener, but, more importantly, the research could lead to better pasture grasses.

Dr Roger Field, Reader in the Lincoln College plant science department, told of the work on turf retardants in a report to the College Council.

Dr Field was overseas in Britain and the United States from November last year until August this year, and his refresher leave report was tabled at today's meeting of the council.

One of his major research interests while overseas was chemical manipulation of plant growth and development with synthetic plant-growth regulators (PGRs).

He saw several interesting developments in using PGRs on grass species with some chemical compounds stimulating tillering, reducing leaf size and reducing overall vegetative growth without influencing reproductive development.

"Such compounds do not have obvious applications for turf retardation or in improving pasture quality when used alone," he said in his report.

However, the chemical compound mefluidide, used to retard reproductive development of pasture grasses, and a new compound, amidochlor, both had promising applications for turf retardation and improving pasture quality.

''Amidochlor probably will be released soon as an amenity turf retardant that can be used by the home gardener," he said.

"Weekly lawn mowing may soon be a thing of the past."

Dr Field said that in a series of trials beef cattle grazing mefluidide-treated pasture were showing significant liveweight gains.

Limited work with mefluidide and related compounds in New Zealand showed there was the possibility of early-flowering grasses, such as perennial ryegrass, being more effectively used.

Some work on the chemical retardation of turf grasses had been carried out at Lincoln College.

Dr Field said the successful discovery of PGRs appeared to be one of the principal research and development objectives of most of the major agricultural chemical companies.

Development costs were enormous at least US$30 million a product – but the potential benefits were large although not yet determined accurately.

Overseas research with cereals confirmed previous findings that existing PGRs were variable in performance and showed no over-all cost benefits in many cases.

One triazole compound had been demonstrated as significantly promoting tillering in barley, and had likely practical application.

Present indications were that PGR development was still haphazard and not rational.

Lincoln College plant science department had used PGRs on sugar beet to maximise fermentable sugar production in an ethanol project.

This had met with only partial success, but there were no improved responses in research elsewhere.

Carrot and red beet had shown improved root growth in British research with some PGRs, but there was no major progress with sugar beet either in

Britain or the United States. Dr Field said no better results had been obtained with other target crops, such as field beans and oil seed rape, where controlling stature, and flower and fruit retention were critical.

Further information from Dr Roger Field, Plant Science Department, Lincoln College, Canterbury, New Zealand.