Rational expectations? Developer behaviour and development cycles in the central London office market

Purpose – Expectations of future market conditions are acknowledged to be crucial for the development decision and hence for shaping the built environment. The purpose of this paper is to study the central London office market from 1987 to 2009 and test for evidence of rational, adaptive and naive expectations. Design/methodology/approach – Two parallel approaches are applied to test for either rational or adaptive/naive expectations: vector auto-regressive (VAR) approach with Granger causality tests and recursive OLS regression with one-step forecasts. Findings – Applying VAR models and a recursive OLS regression with one-step forecasts, the authors do not find evidence of adaptive and naïve expectations of developers. Although the magnitude of the errors and the length of time lags between market signal and construction starts vary over time and development cycles, the results confirm that developer decisions are explained, to a large extent, by contemporaneous and historic conditions in both the City and the West End, but this is more likely to stem from the lengthy design, financing and planning permission processes rather than adaptive or naive expectations. Research limitations/implications – More generally, the results of this study suggest that real estate cycles are largely generated endogenously rather than being the result of large demand shocks and/or irrational behaviour. Practical implications – Developers may be able to generate excess profits by exploiting market inefficiencies but this may be hindered in practice by the long periods necessary for planning and construction of the asset. Originality/value – This paper focuses the scholarly debate of real estate cycles on the role of expectations. It is also one of very few spatially disaggregate studies of the subject matter.

Cryopreservation of winter-dormant apple buds: 1 - variation in recovery with cultivar and winter conditions

The widely-adopted protocol for the cryopreservation of winter buds of fruit trees, such as Malus and Pyrus, was developed in a region with a continental climate, that provides relatively hard winters with a consequent effect on adaptive plant hardiness. In this study the protocol was evaluated in a typical maritime climate (eastern Denmark) where milder winters can be expected. The survival over two winters was evaluated, looking at variation between seasons and cultivars together with the progressive reduction in survival due to individual steps in the protocol. The study confirms that under such conditions significant variation in survival can be expected and that an extended period of imposed dehydration at -4oC is critical for bud survival. The occurrence of freezing events during this treatment suggests that cryodehydration may be involved, as well as evaporative water loss. To optimize the protocol for maritime environments, further investigation into the water status of the explants during cryopreservation is proposed. Keywords: Malus x domestica, cryopreservation, dormant bud, survival, grafting

A genetic linkage map of an apple rootstock progeny anchored to the Malus genome sequence

An apple rootstock progeny raised from the cross between the very dwarfing ‘M.27’ and the more vigorous ‘M.116’ (‘M.M.106’ × ‘M.27’) was used for the construction of a linkage map comprising a total of 324 loci: 252 previously mapped SSRs, 71 newly characterised or previously unmapped SSR loci (including 36 amplified by 33 out of the 35 novel markers reported here), and the self-incompatibility locus. The map spanned the 17 linkage groups (LG) expected for apple covering a genetic distance of 1,229.5 cM, an estimated 91% of the Malus genome. Linkage groups were well populated and, although marker density ranged from 2.3 to 6.2 cM/SSR, just 15 gaps of more than 15 cM were observed. Moreover, only 17.5% of markers displayed segregation distortion and, unsurprisingly in a semi-compatible backcross, distortion was particularly pronounced surrounding the self-incompatibility locus (S) at the bottom of LG17. DNA sequences of 273 SSR markers and the S locus, representing a total of 314 loci in this investigation, were used to anchor to the ‘Golden Delicious’ genome sequence. More than 260 of these loci were located on the expected pseudo-chromosome on the ‘Golden Delicious’ genome or on its homeologous pseudo-chromosome. In total, 282.4 Mbp of sequence from 142 genome sequence scaffolds of the Malus genome were anchored to the ‘M.27’ × ‘M.116’ map, providing an interface between the marker data and the underlying genome sequence. This will be exploited for the identification of genes responsible for traits of agronomic importance such as dwarfing and water use efficiency.

PPG13 and the residential developer

This paper reviews the evidence in favour of the compact city and considers whether it is a viable policy option. Environmentalists, acadenics and politicians have all expressed strong support for the compact city as a basis for sustainable development. A review of the literature broadly confirms the claims made on its behalf, in particular that it is energy efficient and that it plays a crucial role in preventing rural land loss. It is further shown i) that there is nothing inevitable about the established pattern of urban dispersal, and ii) that although urban land is charaterised by a number of contstraints on development,it could in principle satisfy much of the projected demand for housing. Yet urban sprawl continues. Some of the reasons for this in the case of residential development are examined by comparing the residential development process with the principles of sustainable development. The general conclusion of the paper is that proposals for urban containment are likely to be strongly resisted by housebuilders.

The compact city and the residential developer

Although the compact city is widely promoted as a sustainable form of urban development, little attention has been paid to the feasilibity of its implementation in practice. This paper addresses this isse by presenting the findings of a questionnaire study into the viability of the compact city from the perspective of the volume housebuilder. The study shows that, although well aware of the inherent problems witht the compact city, most were generally positive about the need to redirect more development back into urban areas. In addition, they suggested a large number of strategies for change, including i) a role for public sector agencies in overcoming the condstraints on urban sites; ii) the need for an upward reveision of acceptable densities in local plans and design guides; and iii) the creation of a separate, or revised, Use Class Order to enable mixed use development to compete on a level playing field. It is concluded that the residential developer could be engaged in the process of urban containment provided proposals for implementing the compact city of devised. The need for continuing research to test the actual effects of specific schemes is emphasised.

Cryopreservation of winter-dormant apple: III Bud water status and survival after cooling to -30°c and during recovery from cryopreservation

Abstract In a continuing study to improve the efficiency of dormant bud cryopreservation for tissues hardened in maritime climates, the water status of dormant buds was monitored between -4°C and recovery from liquid nitrogen (LN). Measurement of water content, simple thermal analysis and differential scanning calorimetry were employed. Buds did not lose water during cooling to, or holding at -30°C indicating that cryodehydration and/or other adaptive responses contributed during this essential step. A bud exotherm that was an artefact of warming was detected due to necessary handling at -4°C before cooling to -30°C. There were no significant differences between cultivars with respect to water status at -30°C or immediately upon rewarming from LN despite significant differences in post-LN survival. Buds rehydrated in 5 days, but up to 14 days may be needed for recovery for some cultivars. In some instances buds could be grafted without rehydration, taking up water across the early graft union.

Cryopreservation of winter-dormant apple buds: II - tissue water status after desiccation at -4°c and before further cooling

Abstract The established protocol for the cryopreservation of winter-dormant Malus buds requires that stem explants, containing a single, dormant bud are desiccated at -4°C, for up to 14 days, to reduce their water content to 25-30% of fresh weight. Using three apple cultivars, with known differences in response to cryopreservation, the pattern of evaporative water loss has been characterised, including early freezing events in the bud and cortical tissues that allow further desiccation by water migration to extracellular ice. There were no significant differences between cultivars in this respect or in the proportions of tissue water lost during the desiccation process. Differential Scanning Calorimetry (to -90°C) of intact buds indicated that bud tissues of the cultivar with the poorest response to cryopreservation had the highest residual water content at the end of the desiccation process and froze at the highest temperature Keywords: Malus, cryopreservation, dormant bud, dehydration

Development of a dense SNP-based linkage map of an apple rootstock progeny using the Malus Infinium whole genome genotyping array

Background A whole-genome genotyping array has previously been developed for Malus using SNP data from 28 Malus genotypes. This array offers the prospect of high throughput genotyping and linkage map development for any given Malus progeny. To test the applicability of the array for mapping in diverse Malus genotypes, we applied the array to the construction of a SNPbased linkage map of an apple rootstock progeny. Results Of the 7,867 Malus SNP markers on the array, 1,823 (23.2 %) were heterozygous in one of the two parents of the progeny, 1,007 (12.8 %) were heterozygous in both parental genotypes, whilst just 2.8 % of the 921 Pyrus SNPs were heterozygous. A linkage map spanning 1,282.2 cM was produced comprising 2,272 SNP markers, 306 SSR markers and the S-locus. The length of the M432 linkage map was increased by 52.7 cM with the addition of the SNP markers, whilst marker density increased from 3.8 cM/marker to 0.5 cM/marker. Just three regions in excess of 10 cM remain where no markers were mapped. We compared the positions of the mapped SNP markers on the M432 map with their predicted positions on the ‘Golden Delicious’ genome sequence. A total of 311 markers (13.7 % of all mapped markers) mapped to positions that conflicted with their predicted positions on the ‘Golden Delicious’ pseudo-chromosomes, indicating the presence of paralogous genomic regions or misassignments of genome sequence contigs during the assembly and anchoring of the genome sequence. Conclusions We incorporated data for the 2,272 SNP markers onto the map of the M432 progeny and have presented the most complete and saturated map of the full 17 linkage groups of M. pumila to date. The data were generated rapidly in a high-throughput semi-automated pipeline, permitting significant savings in time and cost over linkage map construction using microsatellites. The application of the array will permit linkage maps to be developed for QTL analyses in a cost-effective manner, and the identification of SNPs that have been assigned erroneous positions on the ‘Golden Delicious’ reference sequence will assist in the continued improvement of the genome sequence assembly for that variety.

Grouping of 24 apple cultivars on the basis of starch degradation rate and their fruit pattern

The ripening processes of 24 apple cultivars were examined in the United Kingdom National Fruit Collection in 2010. Basically the starch content, and additionally ground colour, water-soluble solids content and flesh firmness were studied during ripening. The degradation of the starch content was evaluated using a 0–10 scale. A starch degradation value of 50% was taken to be the optimum harvest date, with harvest beginning at a value of 40% and finishing at 60%. Depending on the cultivar, this represented a harvest window of 9 to 21 days. Later ripening cultivars matured more slowly, leading to a longer harvesting period, with the exception of cv. Feuillemorte. Pronounced differences were observed among the cultivars on the basis of the starch degradation pattern, allowing them to be divided into four groups. Separate charts were elaborated for each group that are recommended for use in practice.

Avoiding a bad apple: insect pollination enhances fruit quality and economic value

Insect pollination is important for food production globally and apples are one of the major fruit crops which are reliant on this ecosystem service. It is fundamentally important that the full range of benefits of insect pollination to crop production are understood, if the costs of interventions aiming to enhance pollination are to be compared against the costs of the interventions themselves. Most previous studies have simply assessed the benefits of pollination to crop yield and ignored quality benefits and how these translate through to economic values. In the present study we examine the influence of insect pollination services on farmgate output of two important UK apple varieties; Gala and Cox. Using field experiments, we quantify the influence of insect pollination on yield and importantly quality and whether either may be limited by sub-optimal insect pollination. Using an expanded bioeconomic model we value insect pollination to UK apple production and establish the potential for improvement through pollination service management. We show that insects are essential in the production of both varieties of apple in the UK and contribute a total of £36.7 million per annum, over £6 million more than the value calculated using more conventional dependence ratio methods. Insect pollination not only affects the quantity of production but can also have marked impacts on the quality of apples, influencing size, shape and effecting their classification for market. These effects are variety specific however. Due to the influence of pollination on both yield and quality in Gala, there is potential for insect pollination services to improve UK output by up to £5.7 million per annum. Our research shows that continued pollinator decline could have serious financial implications for the apple industry but there is considerable scope through management of wild pollinators or using managed pollinator augmentation, to improve the quality of production. Furthermore, we show that it is critically important to consider all production parameters including quality, varietal differences and management costs when valuing the pollination service of any crop so investment in pollinator management can be proportional to its contribution.

Pollination deficits in UK apple orchards

Apple production in the UK is worth over £100 million per annum and this production is heavily dependent on insect pollination. Despite its importance, it is not clear which insect pollinators carry out the majority of this pollination. Furthermore, it is unknown whether current UK apple production, in terms of both yield and quality, suffers pollination deficits and whether production value could be increased through effective management of pollination services. The present study set out to address some of these unknowns and showed that solitary bee activity is high in orchards and that they could be making a valuable contribution to pollination. Furthermore, fruit set and apple seed number were found to be suffering potential pollination deficits although these were not reflected in apple quality. Deficits could be addressed through orchard management practices to improve the abundance and diversity of wild pollinators. Such practices include provision of additional floral resources and nesting habitats as well as preservation of semi-natural areas. The cost effectiveness of such strategies would need to be understood taking into account the potential gains to the apple industry.

Agroforestry: integrating apple and arable production as an approach to reducing copper use in organic and low-input apple production

Integrating top fruit production into an agroforestry system, where trees are integrated with arable crop production may have a beneficial effect on the control of plant pathogens such as scab (Venturia inaequalis). Apple yields and pest and disease levels were assessed in a novel apple/arable agroforestry system in Suffolk, and compared with a modern local organic orchard in 2012. Despite 2012 being a very bad year for apple production in the UK, apple yields in the agroforestry system appeared to be comparable with standard figures when scaled up from 2.5% land area under apple production to 100% apples, and even at just 2.5% cover, outperformed the organic orchard used for comparison. Initial indications are that scab levels were over twice as high in the organic orchard than in the agroforestry, indicating that this approach may offer some potential in reducing copper use in organic apple production. However, further research will be required to confirm these early results.