Towards sustainable performance of urban horticulture: ten challenging fields of action for modern integrated pest management in cities.

We identified ten current key challenges for plant protection in cities each of them belonging to a specific field of action of IPM in urban horticulture according to Directive 2009/128/EC. The challenges are: appropriate plant selection, microbiome engineering, nutrient recycling, smart, digital solutions, diversification of vegetation, avoidance of pesticide side effects on beneficials, biorational efficacy assessment, effective pest diagnosis, efficient outbreak control and holistic approaches. They are discussed on the background of the defined urban horticultural core sectors (a) public green infrastructure, including professional plant care, (b) professional field and greenhouse production systems and (c) non-professional private homegardens and allotments.

The Potential for Decision Support Tools to Improve the Management of Root-Feeding Fly Pests of Vegetables in Western Europe.

Several important vegetable crops grown outdoors in temperate climates in Europe can be damaged by the root-feeding larvae of Diptera (Delia radicum, Delia floralis, Chamaepsila rosae, Delia platura, Delia florilega, Delia antiqua). Knowledge of pest insect phenology is a key component of any Integrated Pest Management (IPM) strategy, and this review considers the methods used to monitor and forecast the occurrence of root-feeding flies as a basis for decision-making by growers and the ways that such information can be applied. It has highlighted some current management approaches where such information is very useful for decision support, for example, the management of C. rosae with insecticidal sprays and the management of all of these pests using crop covers. There are other approaches, particularly those that need to be applied at sowing or transplanting, where knowledge of pest phenology and abundance is less necessary. Going forward, it is likely that the number of insecticidal control options available to European vegetable growers will diminish and they will need to move from a strategy which often involves using a single 'silver bullet' to a combination of approaches/tools with partial effects (applied within an IPM framework). For the less-effective, combined methods, accurate information about pest phenology and abundance and reliable decision support are likely to be extremely important.

Comparison between volatile emissions from transgenic apples and from two representative classically bred apple cultivars.

While most risk assessments contrast a transgenic resistant to its isogenic line, an additional comparison between the transgenic line and a classically bred cultivar with the same resistance gene would be highly desirable. Our approach was to compare headspace volatiles of transgenic scab resistant apple plants with two representative cultivars (the isogenic 'Gala' and the scab resistance gene-containing 'Florina'). As modifications in volatile profiles have been shown to alter plant relationships with non-target insects, we analysed headspace volatiles from apple plants subjected to different infection types by gas chromatography-mass spectrometry. Marked differences were found between healthy and leafminer (Phyllonorycter blancardella) infested genotypes, where emissions between the transgenic scab resistant line and the two cultivars differed quantitatively in four terpenes and an aromatic compound. However, these modified odour emissions were in the range of variability of the emissions recorded for the two standard cultivars that proved to be crucial references.

Terpene-mediated parasitoid host location behavior on transgenic and classically bred apple genotypes.

Terpene-mediated interactions between transgenic or classically bred apple genotypes and associated insects were investigated. Apple genotypes were either resistant or susceptible to Venturia inaequalis that causes apple scab. They were subjected to infestation by Phyllonorycter leafminers and/or inoculation with V. inaequalis. Apple leaf extracts were analyzed by gas chromatography-mass spectrometry to quantify squalene, a triterpene known to mediate host location by Pholetesor parasitoids that are specialized on leafminers. Squalene contents in leafminer-infested leaves differed between the transgenic apple scab resistant line and a classically bred cultivar sharing the same resistance gene. This resistant cultivar showed an increase in squalene contents from healthy to leafminer-infested leaves. This was not the case in the transgenic resistant line. However, there was also no increase in the susceptible isogenic cultivar. Behavioral bioassays with parasitoid females also reflected these findings. Hence, alterations in leaf chemistry and corresponding responses of the parasitoid are apparent among classically bred cultivars, rather than in the genetically modified resistant line.

Duplications and copy number variants of 8p23.1 are cytogenetically indistinguishable but distinct at the molecular level.

It has been proposed that duplications of 8p23.1 are either euchromatic variants of the 8p23.1 defensin domain with no phenotypic consequences or true duplications associated with developmental delay and heart defects. Here, we provide evidence for both alternatives in two new families. A duplication of most of band 8p23.1 (circa 5 Mb) was found in a girl of 8 years with pulmonary stenosis and mild language delay. BAC fluorescence in situ hybridisation (FISH) and multiplex amplifiable probe hybridisation (MAPH) showed that the two copies of the duplicated segment were sited, in an alternating fashion, between three copies of a circa 300-450 kb segment from 8p23.1 distal to REPD. Copy number of the variable 8p23.1 defensin domain was consistent with duplication but within the normal range. Duplication of the GATA-binding protein 4 gene (GATA4) in this patient and others with and without heart defects, suggests it is a dosage-sensitive gene with variable penetrance. A cytogenetically similar duplication of 8p23.1 was found at prenatal diagnosis in a fetus, father and grandmother. There was no duplication using BAC FISH but MAPH showed 11 copies of the 360 kb variable defensin domain which is within the expanded range found in previous euchromatic variant carriers. Semiquantitative FISH (SQ-FISH) was consistent with a simultaneous expansion of the adjacent olfactory receptor repeats. These results distinguish duplications of 8p23.1 with clinically significant consequences from benign copy number variants, which have not yet been associated with qualitative or quantitative traits.