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This paper describes a work-in-progress action research project to investigate how technology-enabled learning networks may achieve practical organisational improvement outcomes in the author's own institution, a UK distance learning higher education (HE) context. Collaborative learning technology, typically used for academic learning or professional development, affords the geographically scattered and disparate practitioner stakeholders involved in distance learning module design and delivery the ability to grapple together with a problem area requiring improvement. In this particular context, there is a perennial organisational need to close a feedback loop between remote module tutors and campus based teams, to develop a joint understanding of teaching and learning design challenges, and to put tutors as close as possible to the development of solutions. However, there is insufficient conceptual and practical understanding about the mechanisms by which this unfolding process of technology-enabled organisational learning might happen. Conceptual frameworks in the field of learning networks and networked learning are still developing (Sloep, 2016). The aim of this research is to investigate the active use of learning networks to achieve practical improvement outcomes, and to explore a new conceptual framework covering all stages of the required learning process. The research aims to make an original contribution to the call for actionable knowledge in organisational research, using a collaborative, equitable and rigorous action-oriented and theory-building approach, which also aims to achieve measurable impact.

Many factors are known to influence infection by cereal rusts, including environmental variables such at light, humidity and temperature, the topography of the leaf surface, as well as plant volatiles. However, few studies have aimed to link these factors. Previously, the quantity of light received by wheat seedlings prior to inoculation with Puccinia striiformis f. sp. tritici (Pst) urediniospores was shown to influence yellow rust infection efficiency. In this study we show that germination and the ability of germlings (germinated urediniospores) to enter stomata is enhanced on wheat seedlings subjected to high quantities of light pre‐inoculation with Pst urediniospores, while on seedlings exposed to a long dark period germination and infection were compromised. Using headspace collections and gas chromatography–mass spectrometry (GC–MS) analysis thereof, we link this effect of high light quantity to quantitative changes in the profile of volatile organic compounds (VOCs). We show that the VOCs within headspace collections from wheat seedlings exposed to high quantities of light were able to support greater levels of Pst urediniospore germination than the headspace collections from wheat seedlings exposed to a period of dark. In vitro analysis of individual VOCs identified compounds that enhanced Pst urediniospore germination. These VOCs included the sesquiterpene caryophyllene, the monoterpene α‐pinene, the fatty acid α‐linolenic acid, the organic alcohols 1‐hexanol, 3‐hexen‐1‐ol and 5‐hexen‐1‐ol, the aldehyde cis‐3‐hexenal and the ester hexyl acetate. [ABSTRACT FROM AUTHOR]

Leaf rust, caused by Puccinia triticina (Pt), is a major disease of wheat and a significant problem for wheat production in Brazil. The Brazilian variety Toropi, released in 1965, has maintained high levels of field, adult plant resistance (APR) to leaf rust across global locations, while microscopic studies have indicated prehaustorial resistance mechanisms. Analyses of gene expression in flag leaves of Toropi, during the early stages of Pt infection, were undertaken to explore the mechanisms behind the APR in Toropi. Differential expression of wheat genes was undertaken, comparing Pt‐ to mock‐inoculated and Pt‐ to Pt‐inoculated time points. Analysis of gene expression indicated a strong response to Pt, which was fully active by 6 h after inoculation (hai). More genes were downregulated than upregulated, particularly at 6 and 12 hai. Gene Ontology enrichment analysis indicated a shutting down of RNA and protein synthesis and an early effect on photosynthesis, with disruption of the electron transfer chain. Analyses of upregulated genes identified genes involved in ATP‐binding and protein kinase activity at 6 hai, supporting a rapid metabolic response to Pt infection. A general upregulation of genes involved in transport and metabolism indicated the need to relocate protein and organic‐based resources. Alignment of differentially expressed genes with the genomic regions defining four leaf rust APR quantitative trait loci (QTLs) in Toropi identified candidate resistance genes, including a sugar transporter, a receptor kinase and a seven‐transmembrane MLO family protein. In addition, 60 Pt genes were identified, 11 being annotated as potential effector proteins. [ABSTRACT FROM AUTHOR]

The genetic diversity within wheat breeding programs across Turkey and Kazakhstan was compared with a selection of European cultivars that represented the genetic diversity across eight European countries and six decades of wheat breeding. To focus the measure of genetic diversity on that relevant to disease-resistant phenotypes, nucleotide- binding-site (NBS) profiling was used to detect polymorphisms associated with the NBS motifs found within the NBS--leucine-rich repeat (LRR) class of resistance (R) genes. Cereal-specific NBS primers, designed specifically to the conserved NBS motifs found within cereal R-genes, provided distinct NBS profiles. Although the genetic diversity associated with NBS motifs was only slightly higher within the Eastern wheat genotypes, the NBS profiles produced by Eastern and European wheat lines differed considerably. Structure analysis divided the wheat genotypes into four groups, which compared well with the origin of the wheat genotypes. The highest levels of genetic diversity were seen for the wheat genotypes from the Genetic Resource Collection held in Ankara, Turkey, as wheat genotypes within breeding programs were genetically more similar. The wheat genotypes from Kazakhstan were the most similar to the European cultivars, reflecting the significant number of eastern European cultivars used in the breeding program in Kazakhstan. In general, the NBS profiles suggested that NBS-LRR R-gene usage in winter wheat breeding in Turkey and Kazakhstan differed from that deployed in European cultivars. Key words: disease resistance, genetic diversity, nucleotide-binding-site profiling, Puccinia striiformis f.sp. tritici, yellow rust, wheat. Resume : La diversite genetique au sein de programmes d'amelioration genetique du ble en Turquie et au Kazakhstan a ete comparee a celle presente chez une collection de cultivars europeens representatifs de la diversite genetique dans huit pays europeens au fil de six decennies de selection chez le ble. Afin de focaliser la mesure de la diversite genetique sur la resistance aux maladies, des profils NBS (<< NBS profiling >>) ont ete employes pour detecter le polymorphisme associe aux motifs de liaison nucleotidique (NBS) au sein des genes de resistance (genes R) appartenant a la classe des genes NBS-LRR. Des amorces specifiques des motifs NBS des cereales, concues specifiquement sur la base des motifs conserves chez les genes R des cereales, ont permis de generer des profils distincts. Tandis que la diversite genetique associee aux motifs NBS etait tres legerement superieure au sein des genotypes europeens de ble, les profils NBS obtenus chez les bles orientaux et europeens differaient de maniere considerable. Une analyse de structure a divise les bles en quatre groupes conformement a l'origine des genotypes. La plus grande diversite genetique a ete observee au sein des genotypes de la Genetic Resource Collection d'Ankara en Turquie, tandis que les genotypes appartenant a des programmes de selection varietale etaient plus semblables. Les genotypes du Kazakhstan etaient les plus semblables aux cultivars europeens, ce qui reflete le nombre significatif de cultivars d'Europe de l'Est employes dans les programmes de selection au Kazakhstan. En general, les profils NBS suggerent que l'emploi de genes R de type NBS-LRR au sein des programmes de selection du ble en Turquie et au Kazakhstan differe de celui au sein des cultivars europeens. Mots-cles : resistance aux maladies, diversite genetique, profil NBS, Puccinia striiformis f. sp. tritici, rouille jaune, ble. [Traduit par la Redaction], Introduction Turkey is a major producer and exporter of wheat. As Turkey lies on the edge of the Fertile Crescent and within the Vavilov centre for wheat biodiversity and domestication, [...]

Wheat (Triticum aestivum L.)-Rye (Secale cereale L.) T2BS.2RL translocations were shown to increase grain yield, resistance to biotic and abiotic stresses, and had minor effects on baking quality. The objective of this study was to test agronomic performance and resistance of a new wheat-rye translocation (T2BS.2RL, SLU) to powdery mildew (Blumeria graminis f. sp. tritici (DC.) E. O. Speer), leaf rust (Puccinia triticina Eriks.), stem rust (Puccinia graminis f. sp. tritici Eriks. & Henn.), stripe rust (Puccinia striiformis f. sp. tritici Westend.) and Hessian fly [Mayetiola destructor (Say)]. [F.sub.2] derived [F.sub.4]-[F.sub.6] T2BS.2RL lines, non-translocation lines, and the wheat cultivar Holme were compared using intact seedlings or leaf segments. T2BS.2RL conferred seedling resistance to 17 powdery mildew isolates, 14 leaf rust and one stem rust pathotype. The T2BS.2RL lines were susceptible to 3 stripe rust pathotypes as seedlings, while showing adult plant resistance under natural conditions. Agronomic characters were compared in a 2-yr hill-pint field trial in Sweden. T2BS.2RL lines flowered 2 to 3 d later and had an increased number of spikelets per spike. The T2BS.2RL had no significant effect on yield, straw length, lodging, volume weight, 1000-kernel weight, fertility, [alpha]-amylase activity, or starch or protein content. The multiple disease resistance and the minor negative effects on agronomic performance of the T2BS.2RL, SLU translocation encourage its use in wheat breeding.

Wheat stripe rust, caused by the fungal pathogen Puccinia striiformis f. sp. tritici (Pst), occurs in all major wheat‐growing regions worldwide and poses a constant threat to production. In South Africa, Pst first emerged in 1996 in the Western Cape and has since caused frequent epidemics with three further distinct races (pathotypes) recorded to date. Herein, we undertook detailed genomic‐based analyses of four Pst isolates that represent the four dominant Pst races in South Africa recorded between 1996 and 2005. This analysis identified a number of polymorphic genes with features of known effector proteins and provided additional support of the likely stepwise changes in virulence profile of these South African Pst isolates. Next, we carried out comparative genomic‐based analyses with 54 additional Pst isolates collected across wheat‐growing regions within South Africa between 1996 and 2017 and 58 Pst isolates from East Africa, Pakistan, the UK, and France. This revealed a close genetic relationship between Pst isolates in South Africa and a number from East Africa. Furthermore, we found the South African Pst isolates also grouped closely with isolates identified in the UK in 2013 that were specifically found on triticale, illustrating long‐distance transmission of Pst isolates either between these regions or from a common independent source area. This highlights the critical need for close monitoring of Pst. With wheat being the most planted winter cereal crop in South Africa, investment in continuous surveillance is essential to rapidly identify any future introductions that could quickly lead to rust epidemics. [ABSTRACT FROM AUTHOR]