Rains cut South Australian grain crop

Spring rains have cut South Australia's grain crop this year with the harvest expected to peak at 7.1 million tonnes.

That's 490,000 tonnes below earlier estimates and Agriculture Minister Leon Bignell says the harvest is expected to be above average with an export value of $2.1 billion.

"The harvest has still got a long way to go and the season has been volatile, but I remain optimistic we will reach another above average cropping year," the minister said on Tuesday.