N. D. Cannon

Quality and Value of Organic Grain from Contrasting Breadmaking Wheat Varieties and Near Isogenic Lines Differing in Dwarfing Genes

ABSTRACT Comparisons of Maris Widgeon, an old taller breadmaking variety, were made with more modern varieties of wheat in eight successive field experiments between 1987/88 and 1994/95 at Harnhill Manor Farm, Cirencester, Gloucestershire, U.K. for grain yield, specific weight, protein concentration, SDS-sedimentation volume and Hagberg falling number. The effect of quality of the grain on financial value was investigated by applying a range of penalties for insufficient protein, Hagberg falling number and specific weight. Values for feed and breadmaking quality wheat were also varied. For all of the different pricing scenarios, grain from Maris Widgeon was of lower value than that from the most modern variety. The higher protein concentration of Maris Widgeon, in comparison with Hereward, was insufficient to compensate for lower yields and Hagberg falling numbers. Reduced height genes (Rht1 and Rht2) in isogenic lines of Maris Widgeon, studied in one field experiment, increased grain yield and Hagberg fa...

Bi-cropping white lupins (Lupinus albus L.) with cereals for wholecrop forage in organic farming: The effect of seed rate and harvest dates on crop yield and quality

Bi-crops of spring white lupin (Lupinus albus) cv. Dieta with spring wheat (Triticum aestivum) cv. Paragon and spring triticale (Triticosecale Wittmark) cv. Logo grown on clay loam on Soil Association registered organic land near Cirencester, Gloucestershire, in the UK, gave higher dry matter (DM) yields across different seed rates for the crop mixtures than constituent monocultures. The lupin/triticale mixes gave the highest yields of forage, approaching 20 t ha− 1 DM. Lupin contributions to yield increased with increasing seed rate and later harvest dates (from mid July to late August). Calculated Land Equivalent Ratios exceeding 1 occurred for all lupin/cereal bi-crop treatments across all harvest dates, indicating a competitive resource advantage of the crop mixtures. All lupin/cereal bi-crops were nutritionally superior to the monocrops in chemical quality for crude protein, fibre, and ether extracts.

Implications of climate change predictions for UK cropping and prospects for possible mitigation: a review of challenges and potential responses

The UK, like the rest of the world, is confronting the impacts of climate change. Further changes are expected and they will have a profound effect on agriculture. Future crop production will take place against increasing CO2 levels and temperatures, decreasing water availability, and increasing frequency of extreme weather events. This review contributes to research on agricultural practices for climate change, but with a more regional perspective. The present study explores climate change impacts on UK agriculture, particularly food crop production, and how to mitigate and build resilience to climate change by adopting and/or changing soil management practices, including fertilisation and tillage systems, new crop adoption and variety choice. Some mitigation can be adopted in the shorter term, such as changes in crop type and reduction in fertiliser use, but in other cases the options will need greater investment and longer adaptation period. This is the case for new crop variety development and deployment, and possible changes to soil cultivations. Uncertainty of future weather conditions, particularly extreme weather, also affect decision-making for adoption of practices by farmers to ensure more stable and sustainable production. Even when there is real potential for climate change mitigation, it can sometimes be more difficult to accomplish with certainty on-farm. Better future climate projections and long-term investments will be required to create more resilient agricultural systems in the UK in the face of climate change challenges.

Influences of one-year red clover ley management on subsequent cereal crops

A field experiment of one-year leys was established at Moreton-in-Marsh, Gloucestershire, UK (NGR SP 217 323) with six combinations of red clover, perennial ryegrass and cocksfoot and two fallow control plots in May 2010 to determine the effects of ‘cut and remove’ cropping three times or ‘cut and mulch’ once annually on biomass yield and nitrogen (N) accumulation. The effect of fertility building leys on grain yield and quality were studied in two subsequent cereal crops. There was no evidence during the ley fertility building phase that red clover monoculture (RC) had a strong positive effect on grass productivity when in mixtures, irrespective of the cutting system. In cut/mulch, the red clover/ryegrass/cocksfoot (RCRGCF) mixture had least dry matter and N yields of all red clover-based leys. In the arable phase, all red clover-based leys gave subsequent winter wheat grain yields comparable to those of best conventional management. The cutting system had an effect only on red clover/ryegrass (RCRG) and ryegrass (RG). Maximum grain yield of winter wheat occurred after mulching of RCRG. For spring wheat, the preceding sown species or the cutting system had no effect on grain yield, partly due to preceding wet weather. RC consistently had greater grain protein in both subsequent winter and spring wheat. Growing short-term RC as a fertility-building forage crop could significantly improve grain protein content in both winter and spring wheat, regardless of management. RC could potentially be of economic importance, especially in low input stockless farming, where N supplementation may be limited.

Influences of two-year red clover-grass ley management on nitrogen economy and following wheat performance

A two-year ley field experiment was established in May 2009 with six combinations of red clover, perennial ryegrass and cocksfoot, and two fallow control plots, to determine the impact of ‘cut and remove’ of the crops three times or ‘cut and mulch’ once annually on biomass yield, nitrogen (N) accumulation, soil mineralization and subsequent cereal performance. Farmyard manure was added to one of the fallow treatments at the beginning of the arable phase. The experiment was conducted on a clay loam soil at Moreton-in-Marsh, Gloucestershire, UK (NGR SP 217 323). During the ley fertility-building phase, there was no evidence that red clover (RC) had a synergistic effect on grass productivity when in mixtures, irrespective of cutting system. Accumulated above ground N over the 2 years was greater in cut/removed red clover-based leys (330–365 kg ha− 1) grass and fallow plots. In cut/mulched leys, RC was higher (113 kg ha− 1) than the rest. Soil potential mineralizable N (PMN) was not related to ley N yields but was consistently high in the red clover/ryegrass/cocksfoot (RCRGCF) treatments during winter and spring wheat. There was no indication that wheat yields and quality were improved following any red clover combinations or cutting regimes. These results suggest mixing RC with two grasses, RG and CF are likely to improve soil mineralization potential. Nevertheless, growing red clover leys over 2 years and mulching once annually under variable weather could limit soil N accumulation. In such conditions, growing red clover leys for a shorter period and removing herbage may be a better option.

Organic wheat performance following conventional and non-inversion tillage systems

Field trials were conducted from October 2010 to August 2012 on land registered with the Soil Association, UK, for organic production on the Royal Agricultural Universitys Harnhill Manor Farm near Cirencester, UK, to compare the effects of conventional tillage (CT) involving maximum soil manipulation and 0% soil surface plant residues against conservation tillage strategy including low residue non-inversion tillage (LRNiT) involving minimal soil movements and 30% soil surface plant residues and also high residue non-inversion tillage (HRNiT) with least soil movements and maximum (>50%) retention of soil surface plant residues on organic winter and spring wheat performance. Establishment, growth and the yield response of organic winter and spring wheat for the three cultivation systems were assessed to determine the influence of these tillage treatments. Results showed that the plant establishment and tillers were significantly higher in CT than LRNiT and HRNiT in both cropping seasons. The total number of shoots, ear numbers, dry matter yield, 1000 grain weights and grain yield were significantly higher in the CT and LRNiT than HRNiT for winter wheat, whilst they were significantly higher in the CT than LRNiT or HRNiT for spring wheat. Crop establishment, growth and yield response were influenced by the weather conditions beyond the tillage treatments for the spring wheat compared with the winter wheat. On the basis of these results, a better alternative for CT could be LRNiT for winter wheat. Conversely, for spring wheat, CT had better crop establishment, growth and yield than other forms of cultivation.

Weed manifestation under different tillage and legume undersowing in organic wheat

Field experiments from October 2010 to August 2012 were conducted at the Royal Agricultural Universitys organic Harnhill Manor Farm near Cirencester, UK to explore tillage and legume undersowing effects on dry matter (DM) of broadleaf and grass weed infestation in organic winter and spring wheat. The experiments were designed using a randomized complete block with split plot arrangements. Tillage treatments involved conventional tillage (CT), low residue non-inversion tillage (LRNiT) and high residue non-inversion tillage (HRNiT) as main plots with undersowing white clover (WC), black medic (BM) or non-undersown (Nus) as subplots. In both cropping seasons, among tillage treatments, HRNiT had significantly higher total weed DM than CT or LRNiT. The mid-season assessments for weed species indicated HRNiT as having significantly higher grass weed DM than CT or LRNiT for both the wheat types. Broadleaf weed DM was significantly higher under CT than under LRNiT or HRNiT for winter wheat after GS61, whereas for spring wheat, broadleaf weed DM was significantly higher under CT than under HRNiT throughout the growing season. Undersowing had a significant effect only in spring wheat. Among undersowing treatments, WC had significantly lower total weed DM than BM. The broadleaf weed DM was significantly lower under WC than under BM or Nus. On the basis of these results, increasing the levels of tillage intensity with complete (0%) or minimal (30%) dispersion of soil cover appears to have decreased grass weed and total weed DM. Among undersowing treatments, WC seems to be a more reliable option than BM for spring wheat.

Red clover (Trifolium pratense) in conservation agriculture: a compelling case for increased adoption

ABSTRACT The rapidly growing population will soon require a near doubling of food production. This increase must be achieved in a manner that maintains environmental integrity, preserves public health and resolves food access and distribution equalities. The use of forage legumes in arable rotations can make significant and multidimensional contributions to this sustainable intensification and this paper reviews the potential contribution of red clover (Trifolium pratense L.), with particular reference to sustainable cereal production in conservation agriculture systems. The use of red clover as a tool in soil fertility-building and the multiple benefits to the cropping system in which it is used is described. The benefits discussed include atmospheric nitrogen fixation, soil conservation, structural soil improvements and a suite of agroecosystem services including increased soil microbial activity, the phytoremediation of polluted soils and the provision of food for pollinators. Reported allelopathic weed suppression by red clover cover crops and the role of modern plant breeding in creating new varieties that further enhance system sustainability is also discussed. Finally, as economic considerations will always impact on adoption rates, the profitability of red clover rotations in terms of silage value and yield benefits is taken into account.

Predicting dry matter and crude protein yields of lupin and cereal mono- and bi-crops using a computer model

Spring sown forage lupins and lupin/cereal bi-crops are postulated as suitable crops for wholecrop forage. The Conductance model is proposed as an aid to the evaluation of the yield and quality of potential crop combinations. Spaced plant measurements and field trials are described which took place on The Royal Agricultural Colleges Harnhill Manor Farm Cirencester UK in 2005 and 2006 and which gave good yields of wholecrop forage. The Conductance model was used to make predictions of the likely dry matter and crude protein yields of such combinations. Statistical analysis indicated that the Conductance model was capable of making good predictions of dry matter performance in 0.63–0.75 of the crops studied and of crude protein performance in 0.83 of crops studied. Competition from weeds may have influenced the outcomes of the trial which was carried out on land registered for organic production.