Norwich-based crop scientists have claimed a milestone breakthrough in the global quest for higher-yielding bread wheat.

A new study, led by genetic researchers at the John Innes Centre, has isolated a gene controlling the shape and size of 'spikelets' in the head of cereal plants, which could help seed breeders deliver yield increases in one of the world's most important crops.

The team at the Norwich Research Park say the genetic identification of an agronomically-relevant trait represents a 'significant milestone' in research on wheat – a crop with a notoriously complex genome, five times larger than a human's.

The Wheat Initiative, which co-ordinates global research for the crop, has identified floral architecture as one of the key traits which must be improved if the 1.6pc yield increase needed to feed a growing world population is to be reached.

Dr Scott Boden from the John Innes Centre, whose crop genetics laboratory led the study alongside colleagues from Australia and Cambridge, said: 'This paper is an example of what we are capable of doing in wheat now with a lot of the resources that are coming on board.

'We have gone from the field to the lab and back again. This is a developmental gene that contributes to a lot of agronomically important traits. This knowledge and the resources that come from this study can be used to see if it really does benefit yield.

'We have approached this in an academic sense but we have moved it towards giving breeders tools they can work with to optimise floral development.'

Diversity of floral architecture has been exploited by generations of crop breeders to increase yields and boost grain production. Researchers said the underlying genetic mechanism they have found in wheat is also relevant to a number of other major cereals including corn, barley and rice.

The study, published in the journal The Plant Cell, focuses on the genetics behind a specific mutant trait in bread wheat, where the flowering head of plant is formed of two 'paired spikelets', instead of the usual one. This trait, which bears resemblance to flower production in corn and rice, is a variation which could lead to increase in yield.