Saddle gall midge found in Lincs

WHEAT GROWERS could be mistaking damage from a little known pest for take all, agronomists in Lincs have warned.

A Farmacy agronomist has discovered a wheat field near Newark “heaving” with saddle gall midge.

“White heads have appeared throughout the affected area – it looks just like take all damage,” said the company‘s technical manager Pam Chambers.

“But the typical saddle-type galls can be seen on the stems.”

Half of the 14ha (35 acre) field is affected, with one in ten heads looking “bleached” and others beginning to look poorly, said Ms Chambers.

“We‘re assuming it‘s going to have a drastic effect on yield.”

ADAS entomologist Jon Oakley said he had not heard any reports of infestations, but warm weather in early May was ideal for saddle gall midge.

“The problem is that very few agronomists would recognise the symptoms as pest damage,” he said.

The midge was a particular problem in the early 70‘s, he said, and is restricted to heavy clay soils – Kent heavy Weald clays, Thames Valley and Northants clays being hotspots.

“Unlike other midge it cannot travel far, so a break crop in the rotation will usually knock it on the head.”

Female saddle midge lay eggs on the upper surface of leaves along the veins, forming egg clusters.

After hatching, larvae move down within the leaf sheaths to reach a stem node which they puncture, cutting off nutrient supply to the ear and causing characteristic transverse swellings.

A serious infestation can drop yield by more than 10% in wheat, while barley tends to lodge badly, said Mr Oakley.