Determination of Frequency and Distribution of Hessian Fly (Diptera: Cecidomyiidae) Biotypes in the Northeastern Soft Wheat Region

Fifteen collections of Hessian flies from the northern soft winter wheat region of the United States were used to determine the composition and frequency of biotypes. The wheat cultivars \u27Seneca\u27 (H7Hs), \u27Monon\u27 (H3), \u27Knox 62\u27 (~, H7Hg), and \u27Abe\u27 (Hs) were used as differentials. Biotypes J and L replaced biotype B as the prevalent biotype in Indiana, since wheat cultivars having the Hs and the H6 genes have been grown. Biotype GP, the least virulent of any Hessian fly biotypes, was still present in New York indicating that wheat cuItivars with no genes for resistance are still being grown there. The genetic variability of Hessian fly biotypes that enables them to overcome the resistance in wheat cultivars is discussed

Overview on the current organizational models for cultivar testing for Organic Agriculture over some EU countries.

Variety trials are an important way to evaluate the suitability of existing varieties (conventional, organic, landraces, heirloom, etc.) for organic farming, and are a necessary step in plant breeding and variety registration. However, it is essential that beside on-stations trials, varieties are also tested on-farm in different climatic regions as this gives more accurate and realistic variety performance assessment (Lyon et. al. 2019). Varieties of different crop species are in service to various stakeholders. Thus, their involvement may play an important role in variety trials. They could contribute, with knowledge, seed material in kind or financial support, to build cost-effective variety testing models also for crops that are not grown on a large scale and have small market share. In the report evaluation of different organic variety trials for pre- and post-registration as well as VCU across 15 EU countries (for arable incl. forage, vegetable and fruit crops) is presented through 4 main criteria (trial setup, organizational model, dissemination of results and financial model). Through the range of organizational models of variety trials there were some that were mainly governmentally supported and involving researchers, others that have strong engagement of breeders and seed companies, or are done within seed companies, and some that are running just if project financing is available or some that are mainly established by farmers and done on voluntary basis. Organizational models of variety trials have quite complex nature and therefore, it is not possible to give a general recipe for establishing successful variety trials network. Institutes or initiatives organize trials depending on different socio-economic conditions, such as financial possibilities, economic importance of the crop in the country, chain actors’ engagements, organic sector development, existing trial infrastructure etc. In the report, SWOT analysis of different organizational model groups give better understanding of pros and cons of the different systems and show necessary infrastructure for different models. These analyses will serve as a base for development of guidelines for on-farm trials models that are low budget, with alternative financing and new infrastructures

Pyramiding of Ryd2 and Ryd3 conferring tolerance to a German isolate of Barley yellow dwarf virus-PAV (BYDV-PAV-ASL-1) leads to quantitative resistance against this isolate

Barley yellow dwarf virus (BYDV) is an economically important pathogen of barley, which may become even more important due to global warming. In barley, several loci conferring tolerance to BYDV-PAV-ASL-1 are known, e.g. Ryd2, Ryd3 and a quantitative trait locus (QTL) on chromosome 2H. The aim of the present study was to get information whether the level of tolerance against this isolate of BYDV in barley can be improved by combining these loci. Therefore, a winter and a spring barley population of doubled haploid (DH) lines were genotyped by molecular markers for the presence of the susceptibility or the resistance encoding allele at respective loci (Ryd2, Ryd3, QTL on chromosome 2H) and were tested for their level of BYDV-tolerance after inoculation with viruliferous (BYDV-PAV-ASL-1) aphids in field trials. In DH-lines carrying the combination Ryd2 and Ryd3, a significant reduction of the virus titre was detected as compared to lines carrying only one of these genes. Furthermore, spring barley DH-lines with this allele combination also showed a significantly higher relative grain yield as compared to lines carrying only Ryd2 or Ryd3. The QTL on chromosome 2H had only a small effect on the level of tolerance in those lines carrying only Ryd2, or Ryd3 or a combination of both, but the effect in comparison to lines carrying no tolerance allele was significant. Overall, these results show that the combination of Ryd2 and Ryd3 leads to quantitative resistance against BYDV-PAV instead of tolerance

Sustainable organic plant breeding: Final report - a vision, choices, consequences and steps

In general, the characteristics of organic varieties - and by extension of organic plant breeding - differ from that of conventional breeding systems and conventional varieties. Realising an organic plant breeding system and subsequently steering it to meet changing demands is no less than a mammoth task. The many actions to be undertaken can be divided into short-term commercial and scientific activities, and longer or long-term commercial and scientific activities. Action must be taken in the short-term to ensure adequate quantities of organically propagated plants and seed. This is vital in consideration of Regulation 2092/91/EC which states that, as of 1 January 2000, all propagating material used in organic production must be of organic origin. Additional measures are needed to accelerate the development of organically propagated varieties. Within the breeding sector, variety groups should be established to streamline communication in the chain. Variety groups should have a large contingent of farmers, as well as representatives from the trade branch and breeders. Members should communicate intensively with each other, share experiences, and participate in trials and variety assessments. Questions, wishes and bottlenecks could be recorded by variety groups and passed on to other parties in the chain. The practical details of the plant health concept which is at the basis of organic breeding must be worked out (operationalised). This will require scientific research, for example on: root development and mineral absorption efficiency weed suppressive capacity in situ versus ex situ maintenance resistance breeding in combination with cultivation measures seed-transmitted diseases adaptive capacity alternatives for growth stimulants, silver nitrate and silver thiosulfate in the cultivation of cucumbers and pickles Such research should be carried out by academic institutions (such as Wageningen University and Research Centre) in collaboration with Louis Bolk Institute, Stichting Zaadgoed and private companies. A platform should be established to make an inventory of problems and priorities and to develop research proposals. Farmers could contribute their ideas to the platform through the variety groups. Conclusion A plant breeding system for organic production should be based on the organic concept of plant health and on the organic position on chain relationships. As the total land area under organic production is still relatively small, it is unlikely that commercial breeders will make large investments to develop organic breeding programmes without financial support from other parties, i.e. the government. In this early stage, it is vital that the government provides generous funding and plays an active enabling role. We hope that the action plan to stimulate organic plant breeding, as requested by Parliament, will dovetail with the activities described above

Seasonal Distribution of Forage Yield and Winter Hardiness of Grasses from Diverse Latitudinal Origins Harvested Four Times Per Year in Southcentral Alaska

Relatively short growing seasons at subarctic latitudes require maximum efficiencies in production of forages during the brief growing period. This is necessary to provide adequately for livestock feeding requirements both during the growing season and for preserved forages for use during the relatively longer infeeding period. As elsewhere, forages in Alaska are utilized in several ways; these include (a) usually two harvests per year for preservation as silage, haylage, or hay, (b) more frequent harvests for green-chop feeding, and (c) pasturing rotationally or continuously. Various crop species utilized for forage differ in growth characteristics as well as in their responses to various harvest procedures and schedules; therefore it is understandable that a number of species can be advantageously employed for forage production in Alaska, each to fulfill ideally one of the several ways that forages are utilized. Another limitation affecting forage production in the far north is the modest number of useful perennial legume and grass species and strains adequately winter- hardy to persist dependably under northern climatic constraints (Klebesadel 1970, 1971, 1985; Klebesadel et al. 1964; Wilton et al. 1966)