Development of a protocol that allows safe consumption of the hypoallergenic apple cultivar Santana

The apple (Malus ×domestica) cultivar Santana was shown to have a low allergenicity in a previously reported clinical trial. A protocol was developed to validate these results outside a clinical setting and to market the Santana as a hypoallergenic apple for large-scale consumption. This protocol was designed to ensure safe consumption of the Santana by consumers suffering from apple allergy. We tested the protocol in a pilot in 100 supermarket stores and evaluated in an internet-based survey with 295 respondents. Forty-one percent of the consumers with an apple allergy did not have an allergic reaction to the Santana. Only five percent of the allergic consumers that tried the Santana reported a strong allergic reaction. In concordance with this, the majority (78%) of the mild apple allergic consumers appreciated the Santana. The developed protocol is considered suitable for safe consumption of the Santana providing that information about the possibility of having an allergic reaction among consumers with a mild apple allergy is added to the label

Phylogenetic relationships in Betula (Betulaceae) based on AFLP markers

The genus Betula comprises various species in boreal and temperate climate zones of the Northern Hemisphere. The taxonomy of Betula is controversial and complicated by parallel evolution of morphological traits, polyploidization events, and extensive hybridization and introgression among species. Multilocus molecular data from AFLPs were used to provide phylogenetic information. A large number of polymorphic markers (321 variable bands) were produced in 107 Betula accessions from 23 species and 11 hybrids. The AFLP results were largely congruent with the results from previously examined nuclear DNA markers. Four distinct subgenera were identified within the genus Betula. These subgenera were partly in disagreement with the traditional (but disputed) division of the genus. In addition, the results indicated several groups of conspecific taxa. The majority of the species fell within subgenus Betula and shared a high degree of similarity with B. pendula. All hybrids were associated with this group, and the AFLP data contained signals on putative parents for some of the interspecific hybrids. Subgenus Chamaebetula and part of the Neurobetula species should be merged with Betula. The subgenera Betulenta, Betulaster, and the remaining part of Neurobetula are distinct and well supported. Although our results indicate that four major taxonomic groups can be recognized within the genus Betula, the relationship between them remains unclear. This may be due to the occurrence of hybridization and introgression, which would have a homogenizing effect on the relationships between species. Naturally occurring Betula species of hybrid origin may explain the low bootstrap values within the Betula clade

Hygiëneprotocol komkommer : protocol gericht op voorkomen en tegen gaan van verspreiding van virussen en virusziekten in de teelt van komkommer

In dit rapport wordt ingegaan op de probleemanalyse van virussen in komkommer, de herkenning van komkommerbontvirus, komkommermozaïekvirus, tabaksnecrosevirus, meloenennecrosevirus, pseudo-slavergelingsvirus, courgettegeelmozaïekvirus, watermeloenenmozaïekvirus en komkommerblekevruchtenviroïde en de te treffen hygiënemaatregele

The use of attenuated isolates of Pepino mosaic virus for cross-protection

Pepino mosaic virus (PepMV) has recently emerged as a highly infectious viral pathogen in tomato crops. Greenhouse trials were conducted under conditions similar to commercial tomato production. These trials examined whether tomato plants can be protected against PepMV by a preceding infection with an attenuated isolate of this virus. Two potential attenuated isolates that displayed mild leaf symptoms were selected from field isolates. Two PepMV isolates that displayed severe leaf symptoms were also selected from field isolates to challenge the attenuated isolates. The isolates with aggressive symptoms were found to reduce bulk yields by 8 and 24% in single infections, respectively. Yield losses were reduced to a 0–3% loss in plants that were treated with either one of the attenuated isolates, while no effects were observed on the quality of the fruits. After the challenge infection, virus accumulation levels and symptom severity of the isolates with aggressive symptoms were also reduced by cross-protection. Infection with the attenuated isolates alone did neither affect bulk yield, nor quality of the harvested tomato fruits

Allergische consument is tevreden met Santana

Nederland had twee jaar geleden de primeur: Santana, een hyperallergeen appelras voor mensen met appelallergie. Wageningen UR heeft de ervaringen van de consumenten over 2006 en 2007 onderzocht. De vermindering van de allergische reactie is ongeveer volgens verwachting en de tevredenheid blijkt hoog te zij

Haalbaarheid hygiënestrategie bij tomatenbedrijven om vrij te blijven van pepinomozaïekvirus

Bij een zevental tomatentelers die absoluut vrij wilden blijven van een besmetting met het pepinomozaïekvirus is de teelt gevolgd en begeleid. Deze telers namen tevens deel aan een praktijknetwerk waarin ervaringen werden uitgewisseld

Detectie en beheersing van bacterierot veroorzaakt door Pseudomonas cattleyae in Phalaenopsis

Phalaenopsis growers suffer from mayor losses up to 20% due to bacterial spot. This bacterial infection in caused by the Acidovorax avenae subsp. cattleyae. In practice this bacterial disease is also known as Pseudomonas. This bacterium is causing black leaf spots with a yellow border. Pseudomonas cattleyae is very contagious and is promoted by high temperatures en moist conditions. In this project Groen Agro Control laboratory (Delfgauw) has developed a molecular analysis method to detect Pseudomonas cattleyae in different matrices. The influence of the relative humidity on the development of Pseudomonas cattleyae is investigated during this research. The results show that a relative humidity of 90% strongly promotes infection of the bacteria. A relative humidity of 75% shows no extra dispersion of Pseudomonas cattleyae compared to a greenhouse compartment with a continuous relative humidity of 60%. This knowledge offers the opportunity to safe energy in the cultivation of Phalaenopsis. During this research the effects of water treatments on the dispersion of Pseudomonas cattleyae have been investigated. The results show that a treatment with hydrogen peroxide (20 ppm) offers the best reduction of dispersion. This treatment turns out to be better than the control and all other treatments. This research has led to new insights about the dispersal and optimal growing conditions of this bacteria, but leads to new questions. Questions, about other different dosages and the effects of other water treatments, but also about the optimal level to promote plant growth and reduce bacterial infections, have to be investigated in new research

Broken scaling in the Forest Fire Model

We investigate the scaling behavior of the cluster size distribution in the Drossel-Schwabl Forest Fire model (DS-FFM) by means of large scale numerical simulations, partly on (massively) parallel machines. It turns out that simple scaling is clearly violated, as already pointed out by Grassberger [P. Grassberger, J. Phys. A: Math. Gen. 26, 2081 (1993)], but largely ignored in the literature. Most surprisingly the statistics not seems to be described by a universal scaling function, and the scale of the physically relevant region seems to be a constant. Our results strongly suggest that the DS-FFM is not critical in the sense of being free of characteristic scales.Comment: 9 pages in RevTEX4 format (9 figures), submitted to PR

Aanpak van overmatige wortelgroei in vruchtgroentegewassen

Bij de teelt van komkommer, tomaat en aubergine in uiteen lopende glastuinbouwgebieden in Nederland worden planten waargenomen in de teelt waarbij het wortelgestel een overmatige productie aan wortels laat zien. Het fenomeen dat daarom ook ‘overmatige wortelgroei’ wordt genoemd, uit zich door het ontstaan van veel extra wortels aan het grond- of steenwoloppervlak. De oorzaak van deze overmatige wortelgroei is de bacterie Agrobacterium rhizogenes. Deze bacterie wordt ook wel Agrobacterium radiobacter genoemd . In dit experiment zijn verschillende methoden of middelen onderzocht die de aanwezigheid en infectie van wortels met de Ri-plasmide afkomstig uit Agrobacterium rhizogenes in een kas kunnen voorkomen of verspreiding ervan kunnen inperken. De uitgevoerde proeven hebben als doel: Het ontwikkelen en testen van effectieve maatregelen die de aanwezigheid en verspreiding van overmatige wortelgroei in vruchtgroentegewassen kunnen beperken

Constructing Self-Dual Strings

We present an ADHMN-like construction which generates self-dual string solutions to the effective M5-brane worldvolume theory from solutions to the Basu-Harvey equation. Our construction finds a natural interpretation in terms of gerbes, which we develop in some detail. We also comment on a possible extension to stacks of multiple M5-branes.Comment: 1+19 pages, presentation improved, minor corrections, published versio