A beta-glucoronidase (GUS)-marked strain of Herbaspirillum seropedicae Z67 was inoculated onto rice seedling cvs. IR42 and IR72. Internal populations peaked at over 10(6) log CFU per gram of fresh weight by 5 to 7 days after inoculation (DAI) but declined to 10(3) to 10(4) log CFU per gram of fresh weight by 28 DAI. GUS staining was most intense on coleoptiles, lateral roots, and at the junctions of some of the main and lateral roots. Bacteria entered the roots via cracks at the points of lateral root emergence, with cv. IR72 appearing to be more aggressively infected than cv. IR42. H. seropedicae subsequently colonized the root intercellular spaces, aerenchyma, and cortical cells, with a few penetrating the stele to enter the vascular tissue. Xylem vessels in leaves and stems were extensively colonized at 2 DAI but, in later harvests (7 and 13 DAI), a host defense reaction was often observed. Dense colonies of H. seropedicae with some bacteria expressing nitrogenase Fe-protein were seen within leaf and stem epidermal cells, intercellular spaces, and substomatal cavities up until 28 DAI. Epiphytic bacteria were also seen. Both varieties showed nitrogenase activity but only with added C, and the dry weights of the inoculated plants were significantly increased. Only cv. IR42 showed a significant (approximately 30%) increase in N content above that of the uninoculated controls, and it also incorporated a significant amount of 15N2.

Globally, annual expenditure on ecological restoration of degraded areas for habitat improvement and biodiversity conservation is approximately $18bn. Seed farming of native plant species is crucial to meet restoration goals, but may be stymied by the disconnection of academic research in seed science and the lack of effective policies that regulate native seed production/supply. To illustrate this problem, we identified 1,122 plant species important for European grasslands of conservation concern and found that only 32% have both fundamental seed germination data available and can be purchased as seed. The “restoration species pool,” or set of species available in practice, acts as a significant biodiversity selection filter for species use in restoration projects. For improvement, we propose: (1) substantial expansion of research and development on native seed quality, viability, and production; (2) open‐source knowledge transfer between sectors; and (3) creation of supportive policy intended to stimulate demand for biodiverse seed.

Production of animal-based protein is a significant global source of greenhouse gases, a major driver of agricultural land use and a source of nutrient loss to the environment. In this study, we provide a new assessment of the current sources of proteins in the human diet and analyze the options for increasing the use of plant-based sources, taking the protein quality, as indicated by the amino acid composition, into account. The results demonstrate the importance of sustainable global supply of lysine, one of the amino acids essential for human nutrition. It is demonstrated here that the current production of plant-based lysine that can be considered as replacement of lysine obtained from animal protein largely comes from soybean originating from a small number of countries. There are limited large-scale options to broaden the supply of plant-based lysine, namely increase of soya production outside its current main production areas, increase of production of legumes other than soya or other lysine-rich crops, obtaining plantbased lysine from sources not currently used for human consumption, or manufacturing lysine from non-standard plant-based sources (e.g., through fermentation from sugar). All of these options would require major changes in the structure of global agricultural production and associated agri-food systems and would especially have consequences on agricultural land use.

The long-term sustainability of crop production depends on the complex network of interactions and trade-offs between biotic, abiotic and economic components of agroecosystems. An integrated arable management system was designed to maintain yields, whilst enhancing biodiversity and minimising environmental impact. Management interventions included conservation tillage and organic matter incorporation for soil biophysical health, reduced crop protection inputs and integrated pest management strategies for enhanced biodiversity and ecosystem functions, and intercropping, cover cropping and under-sowing to achieve more sustainable nutrient management. This system was compared directly with standard commercial practice in a split-field experimental design over a six-year crop rotation. The effect of the cropping treatment was assessed according to the responses of a suite of indicators, which were used to parameterise a qualitative multi-attribute model. Scenarios were run to test whether the integrated cropping system achieved greater levels of overall sustainability relative to standard commercial practice. Overall sustainability was rated high for both integrated and conventional management of bean, barley and wheat crops. Winter oilseed crops scored medium for both cropping systems and potatoes scored very low under standard management but achieved a medium level of sustainability with integrated management. In general, high scores for environmental sustainability in integrated cropping systems were offset by low scores for economic sustainability relative to standard commercial practice. This case study demonstrates the value of a 'whole cropping systems' approach using qualitative multi-attribute modelling for the assessment of existing cropping systems and for predicting the likely impact of new management interventions on arable sustainability.

This study focuses on four raspberry (Rubus idaeus) genotypes from two different genetic backgrounds: cvs Glen Prosen and Glen Clova, bred at the Scottish Crop Research Institute (SCRI) and genotypes bred at Horticulture Research International (HRI), East Malling (EM), EM 4997 and EM 5007. The ripe fruit of each genotype pair were characterised subjectively by raspberry breeders as relatively firm or soft, respectively. Different stages of fruit development from each genotype were used to quantify fruit firmness, rates of ethylene evolution and ripening rate. Penetrometry data confirmed suspected firmness differences. Firmness correlated with rates of ethylene evolution. Rates of ethylene production also correlated with receptacle size. Storage of green fruits in 20 μl l−1 ethylene reduced fruit firmness, enhanced respiration rate and colour (anthocyanin) development and stimulated the development of cell wall hydrolase activities. However, during natural ripening in the field, fruit respiration rate declined, which indicates a non‐climacteric ripening pattern. In drupelets, the activities of polygalacturonase (PG), pectin methylesterase (PME), Cx‐cellulase (Cx) and β‐galactosidase (β‐gal.) increased substantially as ripening progressed. More detailed studies with ripe fruit of cv. Glen Clova indicated major isoforms of PG at pIs 3.3, 8.6 and 10.1; of PME at pIs 7.2, 8.5, 8.7, 8.8; of Cx at pI 2.4; and of β‐gal. at pIs 6.3 and 6.7.

Aims Myxospermous seed mucilage is multifunctional and is often found in seeds (or achenes) of species occupying arid environments where the trait may influence seed-dispersal and-germination of seeds. The seed mucilage may also enhance soil-water retention, −hydraulic conductivity and-stability. However, the relationship between seed mucilage quantity, seed germination and seedling traits across environmental gradients which determine water-deficit stress has not yet been ascertained. Methods Therefore, we characterised and tested the relationship between seed mucilage quantity, water-deficit stress responses of seeds and seedlings of 36 accessions of four different Plantago species (P. albicans L., P. coronopus L., P. lagopus L. and P. anceolata L.). These were gathered from six regions across Europe, which presented environmental gradients (of rainfall and temperature), and varying soil qualities. Results Seed mucilage was significantly greater in seeds of accessions experiencing: highest summer temperatures; lowest summer precipitation; soils of the same warm dry regions which had greater capacity to retain water within narrow pore spaces. Under water-deficit stress, seeds with most mucilage exhibited a lower base water potential for germination, suffered least seedling mortality and exhibited the most successful seedling development. Conclusions The findings indicate that seed mucilage quantity appeared as an 'adaptive' trait and there is a relationship between seed-mucilage quantity, seed germination plus seedling survival and development under environmental conditions of highest water-deficit stress.

Grain legumes have declined to a low base in many regions of intensified agriculture yet have the potential both to safeguard food security and satisfy rising ethical demands from food consumers. Here, the scope for legume expansion is examined in a long‐established agricultural region in eastern Scotland where grain legumes declined to <0.3% of cropped area in the 1930s and now vary around 1%. Data from the EU's Integrated Administrative and Control System (IACS) were combined with national agricultural survey to resolve uncertainties over possible restrictions to expansion following 20th‐century intensification. The grain legumes, peas and beans for animal and human consumption, were found to occupy six crop‐grass systems covering a wide range of agronomic input and geographical location. The phase of agricultural intensification between 1950 and 1990 had widened rather than restricted the systems in which they occur and could expand. Moreover, the diversity of the crop‐grass systems provides scope for complementary expansion of several products such as beans for aquaculture, pulses for human consumption, and peas for stockfeed without diminishing the areas of the most profitable crops. Among crop systems, N inputs following 20% legume inclusion would fall from the current 178 to 140 kg/ha (78.6%) at the high‐input end of the range and from 92 to 71 kg/ha (77.0%) at the low‐input end. Further reductions to 50%–60% of the existing N input to intensive crop sequences were estimated assuming a residual fixed nitrogen of 50–75 kg/ha and legume inclusion of 33%. Legume expansion would also bring a range of environmental benefits across all crop‐grass systems. While analysis using IACS brought many insights, major limitations to estimating national N‐balances were identified in lack of data on residual N following legumes, in imported animal feed and in the contribution of forage legumes to grassland.

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