Effects of competition and mowing on growth and reproduction of the invasive plant Erigeron annuus at two contrasting altitudes

Invasive plants are often abundant at frequently disturbed sites such as roadsides, because they benefit from reduced competition or increased nutrient availability. In Switzerland, roadsides are subjected to regular mowing, and to persist in these sites, plants must be able to compensate for the biomass removal. However, the ability to tolerate competition and mowing might decline under less favourable growth conditions, such as those at higher altitudes. I investigated how competition and mowing affect growth and reproduction of Erigeron annuus (L.) Pers., an invasive plant common on Swiss roadsides, and how these effects change with altitude. The experiment was replicated in common gardens at altitudes of 400m and 1,000m asl, representing growth conditions in the main distribution area of E. annuus and at its altitudinal limit, respectively. Vegetative growth was negatively affected by competition at both sites, but especially at 1,000m. The number of capitula was not affected by competition at 400m, but was reduced at 1,000m. Plants regrew vigorously after mowing in both gardens. The effects of mowing on reproductive output were positive at 400m, but negative at 1,000m. These results imply that E. annuus is able to tolerate competition and mowing at low altitudes, but both of these factors hinder its reproduction at higher altitude

Simulating evolutionary responses of an introgressed insect resistance trait for ecological effect assessment of transgene flow: a model for supporting informed decisionmaking in environmental risk assessment

Predicting outcomes of transgene flow from arable crops requires a system perspective that considers ecological and evolutionary processes within a landscape context. In Europe, the arable weed Raphanus raphanistrum is a potential hybridization partner of oilseed rape, and the two species are ecologically linked through the common herbivores Meligethes spp. Observations in Switzerland show that high densities of Meligethes beetles maintained by oilseed rape crops can lead to considerable damage on R. raphanistrum. We asked how increased insect resistance in R. raphanistrum – as might be acquired through introgression from transgenic oilseed rape – would affect seed production under natural herbivore pressure. In simulation experiments, plants protected against Meligethes beetles produced about twice as many seeds as unprotected plants. All stages in the development of reproductive structures from buds to pods were negatively affected by the herbivore, with the transition from buds to flowers being the most vulnerable. We conclude that resistance to Meligethes beetles could confer a considerable selective advantage upon R. raphanistrum in regions where oilseed rape is widely grown

Distribution, growth performance and genetic variation of Erigeron annuus in the Swiss Alps

We investigated whether local adaptation has been important in enabling the invasive apomictic species Erigeron annuus to extend its altitudinal range in the Swiss Alps. We first conducted a field survey along several major roads crossing the Swiss Alps to study the distribution and growth performance of E. annuus along an altitudinal gradient. We then used amplified fragment length polymorphism to assess genetic variation within and among populations originating from different altitudes. To complement the molecular analyses, we compared the performance of genotypes with different distributions (i.e. local, occasional, widespread genotypes) in two common gardens at 400m and 1,000m a.s.l. Although E. annuus was seldom found above 1,000m, plant performance in field populations did not decrease with increasing altitude. However, there was a significant decline in genotypic diversity within populations, and highland (711-1,100m) populations were more differentiated (Gst=0.55) than lowland (200-530m) populations (Gst=0.33). In the common garden experiment, local genotypes (i.e. those restricted to a single population) grew less vigorously than widespread genotypes, and were less likely to reproduce. We found no evidence for on-going adaptive changes and conclude that any selection acting on particular genotypes at the altitudinal limit is weak. This leads us to propose that the patterns in the distribution of genotypic diversity in E. annuus are governed by processes of occasional sexual reproduction, dispersal and extinction that are to a large extent independent of altitud

Assessment of genetically modified maize Bt11\ua0x\ua0MIR162\ua0x\ua01507\ua0x\ua0GA21 and three subcombinations independently of their origin, for food and feed uses under Regulation (EC) No\ua01829/2003 (application EFSA-GMO-DE-2010-86)

In this opinion, the GMO Panel\ua0assessed the four-event stack maize Bt11\ua0 7\ua0MIR162\ua0 7\ua01507\ua0 7\ua0GA21 and three of its subcombinations, independently of their origin. The GMO Panel\ua0previously assessed the four single events and seven of their combinations and did not identify safety concerns. No new data on the single events or the seven subcombinations leading to modification of the original conclusions were identified. Based on the molecular, agronomic, phenotypic and compositional characteristics, the combination of the single events in the four-event stack maize did not give rise to food/feed safety issues.\ua0Based on the nutritional assessment of the compositional characteristics of maize Bt11\ua0 7\ua0MIR162\ua0 7\ua01507\ua0 7\ua0GA21, foods and feeds derived from the genetically modified (GM) maize are expected to have the same nutritional impact as those derived from non-GM maize varieties. In the case of\ua0accidental release of viable grains of maize Bt11\ua0 7\ua0MIR162\ua0 7\ua01507\ua0 7\ua0GA21 into the environment, this\ua0would not raise environmental safety concerns. The GMO Panel\ua0concludes that maize Bt11\ua0 7\ua0MIR162\ua0 7\ua01507\ua0 7\ua0GA21 is nutritionally equivalent to and as safe as its non-GM comparator in the context of the scope of this application. For the three subcombinations included in the scope, for which no experimental data were provided, the GMO Panel\ua0assessed the likelihood of interactions among the single events and concluded that their combinations would not raise safety concerns. These maize subcombinations are therefore expected to be as safe as the single events, the previously assessed subcombinations and the four-event stack maize. The post-market environmental monitoring plan and reporting intervals are in line with the intended uses of maize Bt11\ua0 7\ua0MIR162\ua0 7\ua01507\ua0 7\ua0GA21 and its subcombinations. A minority opinion expressed by a GMO Panel\ua0member is appended to this opinion

Assessment of genetically modified maize MON 87427 × MON 87460 × MON 89034 × MIR162 × NK603 and subcombinations, for food and feed uses, under Regulation (EC) No 1829/2003 (application EFSA‐GMO‐NL‐2016‐134)

Maize MON 87427 ×MON 87460 × MON 89034 × MIR162 × NK603 (five‐event stack maize) was produced by conventional crossing to combine five single events: MON 87427, MON 87460, MON 89034, MIR162 and NK603. The GMO Panel previously assessed the five single maize events and eleven of the subcombinations and did not identify safety concerns. No new data on the single maize events or the 11 subcombinations that could lead to modification of the original conclusions on their safety were identified. The molecular characterisation, comparative analysis (agronomic, phenotypic and compositional characteristics) and the outcome of the toxicological, allergenicity and nutritional assessment indicate that the combination of the single maize events and of the newly expressed proteins in the five‐event stack maize does not give rise to food and feed safety and nutritional concerns. The GMO Panel concludes that the five‐event stack maize, as described in this application, is as safe as and nutritionally equivalent to its non‐GM comparator and the non‐GM reference varieties tested. In the case of accidental release of viable grains of the five‐event stack maize into the environment, this would not raise environmental safety concerns. The GMO Panel assessed the likelihood of interactions among the single events in the 14 maize subcombinations not previously assessed and concludes that these are expected to be as safe as and nutritionally equivalent to the single events, the previously assessed subcombinations and the five‐event stack maize. The post‐market environmental monitoring plan and reporting intervals are in line with the intended uses of the five‐event stack maize. Post‐market monitoring of food/feed is not considered necessary. The GMO Panel concludes that the five‐event stack maize and its subcombinations are as safe as its non‐GM comparator and the tested non‐GM reference varieties with respect to potential effects on human and animal health and the environment

Assessment of genetically modified maize MON89034x1507xNK603xDAS-40278-9 and subcombinations independently of their origin for food and feed uses, import and processing, under Regulation (EC) No1829-2003 (application EFSA-GMO-NL-2013-112)

Maize MON 89034 × 1507 × NK603 × DAS‐40278‐9 (four‐event stack maize) was produced by conventional crossing to combine four single events: MON 89034, 1507, NK603 and DAS‐40278‐9. The GMO Panel previously assessed the four single events and four of their subcombinations and did not identify safety concerns. No new data on the maize single events or their four subcombinations that could lead to modification of the original conclusions on their safety have been identified. The molecular characterisation, comparative analysis (agronomic, phenotypic and compositional characteristics) and the outcome of the toxicological, allergenicity and nutritional assessment indicates that the combination of the single maize events and of the newly expressed proteins in the four‐event stack maize does not give rise to food/feed safety and nutritional concerns. The GMO Panel concludes that the four‐event stack maize, as described in this application, is as safe as and nutritionally equivalent to its non‐GM comparator and the non‐GM reference varieties tested. In the case of accidental release of viable grains of the four‐event stack maize into the environment, this would not raise environmental safety concerns. The GMO Panel assessed the likelihood of interactions among the single events in the six maize subcombinations for which no experimental data were provided, and concludes that these are expected to be as safe as and nutritionally equivalent to the single events, the previously assessed subcombinations and the four‐event stack maize. The post‐market environmental monitoring plan and reporting intervals are in line with the intended uses of the four‐event stack maize. No post‐market monitoring for food/feed is necessary. The GMO Panel concludes that the four‐event stack maize and its subcombinations are as safe as its non‐GM comparator and the tested non‐GM reference varieties with respect to potential effects on human and animal health and the environment

Assessment of genetically modified maize Bt11 × MIR162 × MIR604 × 1507 × 5307 × GA21 and subcombinations, for food and feed uses, under Regulation (EC) No 1829/2003 (application EFSA‐GMO‐DE‐2011‐103)

Maize Bt11 × MIR162 × MIR604 × 1507 × 5307 × GA21 (six‐event stack maize) was produced by conventional crossing to combine six single events: Bt11, MIR162, MIR604, 1507, 5307 and GA21. The GMO Panel previously assessed the six single events and 22 of their combinations and did not identify safety concerns. No new data on the maize single events or their 22 combinations that could lead to modification of the original conclusions on their safety have been identified. The molecular characterisation, comparative analysis (agronomic, phenotypic and compositional characteristics) and the outcome of the toxicological, allergenicity and nutritional assessment indicate that the combination of the single maize events and of the newly expressed proteins in the six–event stack maize does not give rise to food and feed safety and nutritional concerns. The GMO Panel concludes that the six‐event stack maize, as described in this application, is as safe as and nutritionally equivalent to its non‐GM comparator and the non‐GM reference varieties tested. In the case of accidental release of viable grains of the six‐event stack maize into the environment, this would not raise environmental safety concerns. The GMO Panel assessed the likelihood of interactions among the single events in the 34 maize subcombinations not previously assessed and concludes that these are expected to be as safe as and nutritionally equivalent to the single events, the previously assessed subcombinations and the six‐event stack maize. The post‐market environmental monitoring plan and reporting intervals are in line with the intended uses of the six‐event stack maize. Post‐market monitoring of food/feed is not considered necessary. The GMO Panel concludes that the six‐event stack maize and its subcombinations are as safe as its non‐GM comparator and the tested non‐GM reference varieties with respect to potential effects on human and animal health and the environment

Effects of competition and mowing on growth and reproduction of the invasive plant Erigeron annuus at two contrasting altitudes

ISSN:0253-1453ISSN:1420-906