21 January 2000

French analysis helps breeders hit targets

By Marianne Curtis

SENDING samples of maize varieties grown in the UK to France for analysis should enable French maize breeders to better match UK requirements for both agronomic and nutritional requirements.

French plant breeding company Limagrain, which markets LG varieties through Nickerson in the UK, has bred separate lines of maize for grain or silage for the past 20 years.

This enables Limagrain to concentrate on improving nutritional characteristics in its silage varieties, its marketing manager Nicolas Chaufferin explained at a press briefing last week.

"As well as agronomic goals, such as yield and standing power, we also focus on improving whole plant digestibility, cell wall digestibility and feed intake characteristics.

"Newly developed analysis methods using mini-silos mean we can also take into account the effect of ensiling on nutritional characteristics when developing varieties," said Mr Chaufferin.

In a new initiative from Nickerson, 100 samples of each LG variety will be sent to France annually for whole plant and silage analysis. Analysis in France is necessary because its maize nutritional analysis methods are more advanced than the UKs, explained the Maize Growers Associations Gordon Newman.

"Although we now have a digestibility figure on the NIAB varieties list, it doesnt tell us much because all varieties come out with a similar figure. The French maize analysis system gives a truer picture of nutritional value to the animal.

"The French system isnt used here because, unfortunately, there is an unwillingness in the industry to adopt systems that havent been developed in this country. Sending UK samples to France means plant breeders can accommodate our different climatic and soil conditions when developing varieties."

Minimum standards have been set for LG varieties to ensure silage is of a high agronomic and nutritional quality, said Nickerson product manager Peter Schofield. These are 15t DM/ha yield, 38% dry matter, 71% whole plant digestibility, 52% cell wall digestibility, 62g/kg metabolisable protein and 11.2MJ/kg metabolisable energy.

The standards help focus growers attention on maize nutritional quality rather than cob ripeness, added Mr Schofield.

Early varieties

"Early maturing varieties are often harvested when cobs are over-ripe and the green part of the plant is dying. Over-ripe kernels are poorly digested by animals.

"As more is found out about the nutritional characteristics of maize, the company hopes to be able to match varieties to particular production systems such as high or low yielding herds within the next three years."

However, as nutritional information is not currently available for most varieties marketed in the UK, Mr Newman advises growers to select varieties based on the following criteria.

"Choose three varieties for your farm: The first should be one that has been grown previously and is known to perform well on your unit. The second should be drought tolerant, providing insurance in dry years and the third should be a new variety."

MAIZE VARIETIES

&#8226 Nutrition characteristics important.

&#8226 Need better analysis system.

&#8226 Match production systems?

MAIZE VARIETIES

&#8226 Nutrition characteristics important.

&#8226 Need better analysis system.

&#8226 Match production systems?

The French system of analysing maize gives a truer picture of nutritional value to the animal than the British system, says Gordon Newman.