UK scientists hunt for biomass grass types in Asia

Scientists of the UK's Institute of Grassland and Environmental Research (IGER) have collected novel types of the giant grass Miscanthus giganteus x from China, Taiwan and Japan in order to boost the development of biomass from energy crops. A plant-breeding process is now underway with the samples.

Biomass crops are becoming increasingly important as concerns grow about climate change and the need to replace carbon dioxide producing fossil fuels – oil ,coal and gas – with carbon-neutral renewable sources of energy. Energy crops like Miscanthus form the basis of a series of possible end products, either in gaseous (biogas), liquid (ethanol, bio-oil, synthetic biofuels) or solid form (combustion for power and electricity generation).

To succeed in this role, a crop has to grow rapidly and yield a reliable, regular harvest. A prime candidate for the UK is Miscanthus, also known as elephant grass, a perennial species native to Asia that can grow more than 4 metres of bamboo-like stems in a year.

“A number of trials across Europe have confirmed the potential of this highly impressive grass from East Asia. But existing varieties haven't been bred specifically for high yields, and we know that we can make major gains through scientifically-based plant breeding.” - Dr John Clifton-Brown, leads the breeding programme of Miscanthus at the Institute of Grassland and Environmental Research.

The UK Department for Environment, Food and Rural Affairs (Defra) funded the collecting trip to seek out new specimens suitable for incorporation into his breeding programme. Planning of the trip in conjunction with counterparts in Asia took months to put together, but was helped enormously by the presence in IGER of Lin Huang, from Taiwan , who is a biological data analyst at the Institute. Lin Huang also joined the expedition, which took place in October, as interpreter and recorder.

A key aim was to find plants with characters such as extreme height, thick stems and dense growth. The team found some extraordinary material:
biomass :: bioenergy :: biofuels :: energy :: sustainability :: miscanthus :: elephant grass :: biomass :: cellulosic ethanol :: biomass-to-liquids :: biogas ::

“We found plants with superb agronomic potential, some growing as much as 4-5metres in a year,” said Dr Clifton-Brown. “And in Taiwan, even at 1800 metres above sea level, we found plants as tall as 3-4 metres.” In total they brought back some 250 samples for the IGER breeding programme. Samples have been shared with donor countries and agreements to share any commercial benefits have been made with each country. Where possible, seed was collected but otherwise rhizomes had to be dug up. Collected samples are held in strict quarantine to avoid any risk of the introduction of new pests or diseases. At present, in contrast to willow, another prospective energy crop, Miscanthus is surprisingly immune to pest and disease attack.

Miscanthus grows across a wide geographical area, so the journey took in Japan and Taiwan , as well as some remote parts of central China , where few westerners go. “It was an amazing experience,” Dr Clifton-Brown said. “In China we saw bargefuls of Miscanthus being collected for paper-making, in Taiwan we drove along perilous mountain passes above the clouds in ‘Miscanthus heaven' and in Japan we had close encounters with some particularly vicious looking spiders!

Work will now begin on breeding new Miscanthus varieties suitable for conditions in the UK. Armed with the new material from Asia, the researchers aim to increase yield, and improve other traits associated with chemical composition while retaining tolerance to the stresses such as long dry summers.

By increasing genetic diversity, breeding of improved Miscanthus will also reduce genetic vulnerability of Miscanthus. Cultivation is currently based on a single clone. “Although Miscanthus is a tough plant, genetic variety will offer protection against unexpected pests and diseases.” said Dr Clifton-Brown.

In contrast to arable crops such as wheat, which have also been proposed as energy crops, miscanthus has lower fertiliser requirements, less requirement for ploughing, positive effects on biodiversity and therefore has a less adverse environmental impact. Biomass crops are beginning to make a significant impact on the UK agricultural sector, and the new breeding programme looks set to secure the future of Asian elephant grass as an option for farmers.