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Agroecological service crops are introduced into the vegetable crop rotation to provide agroecosystem services, and are a key strategy for weed management in organic systems. Organic farmers across Europe usually terminate these crops before cultivation of the subsequent cash crop, using them as green manure. Recently, the in-line tillage-roller crimper has attracted interest across Europe. It allows flattening the agroecological service crops and creates a narrow furrow that facilitates the fertilization and transplantation of organic vegetables. In Europe, most of the research on this technology has been carried out in Italy, and no studies are available analyzing its effect on weed density, weed species richness, and community composition in different vegetable crops, soils, and climatic conditions across Europe. We compared the effects of the usage of in-line tillage-roller crimper versus green manure on the weed abundance, species richness, and community composition in fourteen original datasets from five countries over 2 years. The support for a common effect of in-line tillage-roller crimper across trials was tested by means of a meta-analytic approach based on a weighted version of Stouffer's method. Our results indicate that in-line tillageroller crimper management reduced weed density by 35.1% on average in comparison with green manure, and this trend was significant across trials. Moreover, we document a significant reduction of weed species richness under this technique and significant but, in general, minor changes in the weed community composition across the trials. Therefore, this study provides for the first time a solid evidence of the effectiveness of this management technique to reduce weed density at the early stages of crop growth across a wide range of vegetable systems and production conditions in Europe. Nonetheless, it is important to note that the effect of this technology can be strongly affected by variations in cropping conditions.

Different plant genotypes react differently in different climates. A field experiment was carried out to estimate the growth performance, productivity and diseases susceptibility of spring barley varieties in the Slovenian climate. We received some varieties, mainly of Nordic origin, from the Technical University of Denmark, a COBRA project partner, which were previously tested in estimated future climate in RERAF phytotron. Varieties of the highest grain yield (3,993 kg ha -1 in 'Evergreen' to 5,146 kg ha -1 in 'Sebastian') were rather shorter (58.7 cm to 67.1 cm) and mostly had the highest specific grain weight (54.3 to 58.6 kg 100 L -1 ) and 1000-kernel weight (30.2 to 37.1 g). They developed 1,561 to 2,532 tillers m -2 and 515 to 840 ears m -2 and reached a heading stage between 13 th and 25 th of May. The tested varieties seem rather insusceptible to most common diseases, but susceptible to cereal leaf beetle attacks.

The objective of the present study was to analyze and compare the allelopathic activities of weedy and grain amaranths. For this purpose, the seeds of garden cress (Lepidium sativum L.) were germinated on filter paper moistened with aqueous extracts of Amaranthus retroflexus L. and Amaranthus cruentus L. cv. 'G6'. The extracts were prepared from fresh roots, stems, leaves, and inflorescence with seeds (1: 2 w/v in water) and used, either undiluted (100%) or at varying concentrations (75, 50, and 25%). Although, all the extracts delayed germination, the leaf extracts of both species and the inflorescence extracts of grain amaranth, proved the more powerful. The root and stem extracts of grain amaranth reduced germination significantly only when used undiluted, whereas none of the extracts at 25% concentration, except that of the pigweed leaves, affected root elongation. However, in some cases, root elongation was even stimulated. Compared to the pigweed amaranth, the grain species exerted a stronger inhibitory effect on the germination process, and root elongation.

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