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Miscanthus genotypes exhibit key characteristics that make it an excellent sustainable source of biomass. Miscanthus is perennial, requiring few inputs for growth and thus has a highly favourable energy ratio and produces biomass yield for up to 20 years. Miscanthus is typically propagated clonally via rhizome which is expensive, and it is difficult to scale up existing and new varieties to plant large areas rapidly. Propagation by glasshouse raised plug plants from seed is a new alternative but requires optimisation from growth in plugs to field establishment and senescence. This study focussed on the optimisation of the first year of a seeded Miscanthus stand, from germination and seedling phase to harvest the following spring. Germinating seedlings under mulch film in the glasshouse improved seedling vigour and germination rate, leading to larger plants at field planting, but the larger plants did not reliably yield higher biomass production at harvest, leading to further experimentation for the optimum seedling morphology and growth conditions. Combinations of plug design and planting date were tested. Establishment success in field was more likely in warmer, wetter conditions earlier in the season, as opposed to dry, summer conditions which increased the risk of plug desiccation, especially under mulch film. Planting environment and post planting care had a significant effect on overall yield, whereas initial plug morphology did not. Increasing glasshouse module sizes from 35cm3 of soil to 45cm3 improved plug plant development and planting time flexibility. Experimentation with different seedling morphologies concluded that larger plants with strong root biomass were more likely to survive planting into the field, but correlations with yield were less significant, suggesting that increased establishment percentage should be the first priority when growing seeded Miscanthus. The study concluded that individual plant growth over the season is extremely difficult and complex to predict or influence due to a multitude of interacting environmental and physiological factors. Finally, plant growth regulators were investigated to encourage senescence in a hybrid that had previously failed to successfully overwinter in the UK. Applications of exogenous ethephon at 480g/L stock solution greatly altered leaf colouration in treated plants, suggesting this approach has potential for commercial application; however, the consequences of the induced senescence need further investigation.

Miscanthus is an important source of biomass and can be grown on marginal sites so as not to compete with food crops. The crop requires few inputs, is perennial, and yield increases to economic levels over around three years, so Miscanthus must be cost effective to establish. Establishment by seed is more cost effective than by rhizome; therefore, improving seed agronomy is vital for the success of the crop. This study contributes an assessment of many previously unknown factors on Miscanthus germination. Hormone treatments and cluster sowings are tested, predominantly for direct sowing but also for plug-based establishment. Cluster sowings improved the chance of establishing a plot, some first year competition effects were identified; however, the number of seeds required may not be economic without additional treatments. An optimal set of treatments for successful germination was identified using a Taguchi design experiment. Complex hormone interactions were tested plus effects of light and seed priming. Methodologies and automation of seed germination assessment were developed. The unreliability of manual seed germination scoring with highlighted and germination scoring was only assisted by imaging due to low throughput. A selection of Miscanthus genotypes were characterised, for base temperatures of germination and elongation. From this information, a model was parameterised for Miscanthus seed germination; this was tested against different sowing methods in field and laboratory conditions and against real data collected from experiments that tested first year agronomic methods, such as sowing time, film, and seed priming. Film was found to have positive temperature effect but mixed effects on germination due to soil water, while priming had little benefit. This model can be used and refined further to test and develop hypotheses for future improvements in seed agronomy.