Genetic tweaks helping wheat to use nitrogen more efficiently have been one of the keys to raising yield and quality.
Prof Malcolm Hawkesford, head of the Designing Future Wheat Institute Strategic Programme at Rothamsted Research, says: “Since 2004 we’ve conducted field trials of more than 60 varieties to examine yield, quality and nitrogen use efficiency (NUE) at various nitrogen rates.
“This unique dataset has given us insights into genetic and climatic trends including annual variability.
For example, we’ve shown how recent higher yielding varieties can better use more N and hence have a higher NUE.”
The Genetic Improvement Networks, or ‘GINs’, were set up to bridge a gap between researchers and plant breeders, once described as a ‘valley of death’, by creating pre-breeding material having new profitable and sustainable characters.
WGIN4, the latest in a series of projects on wheat starting in 2003, aims to improve the resilience of the crop through genetics and targeted trait analysis, explains Rothamsted’s lead scientist, Prof Kim Hammond-Kosack.
“A third of our effort goes on developing new genetic resources,” she says.
“This has involved purifying the Watkins wheat collection, never previously used in commercial wheat breeding, precise sexual crossing, and seed multiplication through generations in glasshouses and then small field plots.
“The new wheat germplasm arising is made available directly from the researchers involved and via the Germplasm Resources Unit at the John Innes Centre.”
The material, free of intellectual property, may be used by all breeders.
Over the years, various methods have been used to place molecular markers on each of wheat’s 21 chromosomes in the new germplasm.
“This gives each genetic stock a unique fingerprint,” says Prof Hammond-Kosack.
“These markers are also used for fine mapping the location of genes controlling each desired trait on the different chromosomes.
” The rest of the research effort goes on analysing various traits under four overarching challenges:
• Resilience: Resistance to slugs, BYDV*, septoria, yellow rust and take-all.
• Sustainability: Yield stability, spring drought, lodging* and stem anchorage*.
• Quality and yield: Grain protein and specific weight*, nitrogen use efficiency and nutrient partitioning as affected by N input and disease*.
• Efficiency: Enhancing nitrogen resource efficiency.
The analysis of various desirable crop traits is done by specialised teams or individuals using established and/or newly developed quantitative screening methods to detect variation in each desired trait, says Prof Hammond-Kosack.
“Sometimes the screening is by eye, but often it involves handheld devices, specially designed larger equipment, or analysing images collected by high specification drones.”
It had been hoped that WGIN4 would become more closely involved with the AHDB monitor and strategic farms.
“But farmers don’t have equipment to do small plot trials and WGIN researchers don’t have enough seed of promising lines to undertake field-scale trials,” says Prof Hammond-Kosack.
“So, the ‘valley of death’ remains but has shifted location.
“The Rothamsted stand at Cereals, JIC annual Plant Breeder days and the annual stakeholder meeting [currently held online] are great ways to see how we evaluate the new traits, see the latest results, and meet the WGIN scientists.”