Die Dauersporangien des Kartoffelkrebserregers, Synchytrium endobioticum, stellen aufgrund ihrer Widerstandsfähigkeit gegenüber chemischer Behandlungen eine besondere Gefährdung in Form von ...Langzeitkontamination von Resterden und Ackerflächen dar. Sie weisen ein breites Spektrum an Erscheinungsformen mit spezifischen Charakteristika auf und sind deshalb eine besondere Herausforderung bei der sicheren Diagnose von Kartoffelkrebs. Neben der Bewertung als Synchytrium endobioticum stellt die Beurteilung der Vitalität des einzelnen Sporangiums auf Basis mikroskopischer Untersuchungen eine Herausforderung dar. Die Referenzbildsammlung soll eine Entscheidungshilfe und Schulungsmaterial für die Diagnoselabore bieten. Exemplarisch werden Sporangienbilder verschiedener Kategorien bewertet und Besonderheiten hervorgehoben. Die Referenzbildsammlung ist auf der Homepage des Nationalen Referenzlaboratoriums des Julius Kühn-Instituts für registrierte Nutzer abrufbar.
We have extended previously published sets of simple sequence repeat markers for Synchytrium endobioticum, selected to be polymorphic for the German-standard isolates of pathotypes P1, P2, P6, P8, ...and P18. These markers also complement the extensive published information on DNA polymorphisms for the mitogenomes of Synchytrium endobioticum. This extended set of 35 markers representing 73 alleles differentiated 51 isolates from Europe and North America into three large, well-separated clusters and subclusters using dendrogram analysis, principal coordinates analysis (PCoA), and population substructure analysis using STRUCTURE 2.3.4 software. This suggests a limited number of introgressions of the wart disease pathogen into current potato growing areas, followed by recombination and admixture of populations through human activities. The new markers extend the published marker sets and are useful tools for future analyses of population structure and dynamics in Synchytrium endobioticum, which are necessary to understand the biology of the interaction between the pathogen and its potato host and to develop future control strategies.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
BACKGROUNDPearl millet (Pennisetum glaucum (L.) R. Br., syn. Cenchrus americanus (L.) R. Br) is an important cereal and fodder crop in hot and arid environments. There is great potential to improve ...pearl millet production through hybrid breeding. Cytoplasmic male sterility (CMS) and the corresponding nuclear fertility restoration / sterility maintenance genes (Rfs) are essential tools for economic hybrid seed production in pearl millet. Mapping the Rf genes of the A4 CMS system in pearl millet would enable more efficient introgression of both dominant male-fertility restoration alleles (Rf) and their recessive male-sterility maintenance counterparts (rf).RESULTSA high density linkage map based on single nucleotide polymorphism (SNP) markers was generated using an F2 mapping population and genotyping-by-sequencing (GBS). The parents of this cross were 'ICMA 02777' and 'ICMR 08888', which segregate for the A4 Rf locus. The linkage map consists of 460 SNP markers distributed mostly evenly and has a total length of 462 cM. The segregation ratio of male-fertile and male-sterile plants (3:1) based on pollen production (presence/absence) indicated monogenic dominant inheritance of male-fertility restoration. Correspondingly, a major quantitative trait locus (QTL) for pollen production was found on linkage group 2, with cross-validation showing a very high QTL occurrence (97%). The major QTL was confirmed using selfed seed set as phenotypic trait, though with a lower precision. However, these QTL explained only 14.5% and 9.9% of the phenotypic variance of pollen production and selfed seed set, respectively, which was below expectation. Two functional KASP markers were developed for the identified locus.CONCLUSIONThis study identified a major QTL for male-fertility restoration using a GBS-based linkage map and developed KASP markers which support high-throughput screening of the haploblock. This is a first step toward marker-assisted selection of A4 male-fertility restoration and male-sterility maintenance in pearl millet.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Dem JKI wurde im April 2019 durch das Bundesministerium für Ernährung und Landwirtschaft (BMEL) die Funktion des nationalen Referenzlaboratoriums (NRL) für Schadorganismen der Pflanzen zugewiesen. ...Mit dieser Funktion des NRL für Deutschland sind bestimmte Zuständigkeiten und Aufgaben verbunden, die in der EU-Verordnung 2017/625 (EU, 2017) geregelt sind. Dazu gehören auch Referenzuntersuchungen bzw. die Diagnose von Quarantäneschadorganismen (QSO). Das NRL stellt eine übergeordnete Einheit innerhalb des JKI dar. Durch insgesamt 14 Prüflabore der JKI-Institute für Pflanzenschutz in Ackerbau und Grünland (A), nationale und internationale Angelegenheiten der Pflanzengesundheit (AG), Epidemiologie und Pathogendiagnostik (EP), Pflanzenschutz in Gartenbau und Forst (GF), Pflanzenschutz in Obst- und Weinbau (OW) wird die Referenzfunktion bei der Diagnose zu verschiedensten (Quarantäne)-Schadorganismen der Pathogengruppen Bakterien, Insekten, Nematoden, Pilze (einschließlich Oomyceten), Phytoplasmen und Viren wahrgenommen.
ABSTRACT
Diets of West African (WA) smallholder farmers are built on pearl millet Pennisetum glaucum (L.) R. Br.. Sustainable pearl millet hybrid breeding is challenging in WA, mostly due to an ...extensive genetic diversity combined with a high degree of admixture. In the absence of natural heterotic groups, understanding combining ability patterns can enable systematic development of heterotic groups and make sustainable hybrid breeding feasible. The objectives of this study were to evaluate heterosis and combining ability patterns and their relationship with genetic distance among WA pearl millets based on population hybrids, and to derive conclusions for future breeding programs. Therefore, 17 open‐pollinated varieties (OPVs) were crossed in a diallel mating design and tested together with their offspring in nine environments over 2 yr in Niger and Senegal. Genetic distances between the OPVs were evaluated with twenty microsatellite markers. Average panmictic better‐parent heterosis (PBPH) was 18% (1–47%) for panicle yield. A principal coordinate analysis based on genotyping results separated parental OPVs clearly by geographic origin. Although there was no relationship between genetic distance among OPVs and PBPH, we confirmed good combining ability among selected OPVs from Niger vs. Senegal. The identified cultivars (Nigerien CIVT, H80‐10Gr, and Taram and Senegalese Thialack 2 and Souna 3) with high combining ability are recommended for founding divergent heterotic pools targeting long‐panicle pearl millet hybrids. Our study shows the benefits of population hybrids and represents an important step to identify combining ability patterns and initial heterotic groups for WA pearl millet hybrid breeding.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Abstract
PURPOSE: Advances in treatment have increased survival rates and quality of life of pediatric CNS tumor patients leading to a growing number of long-term survivors. However, there is ...sufficient clinical and scientific evidence for the need of a highly specialized lifelong follow-up care due to multidimensional late effects. Furthermore, adolescence and young adulthood are challenging age periods when patients frequently get lost to follow-up potentially having severe impact on health and well-being. Since 2020, we have established a structured transfer of long-term survivors older than 18 years to a newly founded highly specialized adult care follow-up setting for childhood cancer survivors (IONA). The aim of this study was to evaluate the current transition process. RESEARCH DESIGN: The standard of care transition process at the neuro-oncology unit of the MUV includes a joint appointment with the patient, a pediatric neuro-oncologist, psychologist and/or social worker and the team of the adult care facility (physician, psychologist). Different elements are used to end care safely in the pediatric structure and building trust in the upcoming out-patient-department at the same time. The transition process was evaluated statistically and analyzed qualitatively with regard to the factors that define a safe transition. RESULTS: After two years (01/2020-12/2021) 114 patients had a joint transition appointment, two patients contacted IONA directly. Shortly after the joint appointment all patients had a scheduled follow-up meeting at IONA. 102 patients (87.9%) showed up, seven patients (6%) already had a planned appointment, two patients (1.7%) were in contact with IONA but had no possibility to show up in person. Only five patients (4.3%) did not attend the appointment and were lost to follow-up. CONCLUSION: A structured interdisciplinary transition concept is a successful option to establish controlled and patient-safe transition from pediatric to adult care setting.
ABSTRACT
Pearl millet Pennisetum glaucum (L.) R. Br. was domesticated in Sahelian West Africa. This highly outcrossing crop is one of the most important staple cereals in the semiarid tropics, ...adapted to very harsh rain‐fed conditions. Agro‐morphological characterization of local germplasm is very important to better understand existing diversity, ease targeted genetic broadening of breeding populations, and potentially link this knowledge to genotypic information. The objectives of our study were to (i) characterize West and Central African (WCA) pearl millet accessions based on their agro‐morphological traits; (ii) evaluate the possibility to group accessions based on their agro‐morphological characteristics; (iii) determine geographic patterns of phenotypic differentiation; and (iv) derive conclusions for pearl millet improvement in WCA. A total of 360 early‐to‐medium maturity accessions were phenotyped for 12 agro‐morphological traits at six environments in WCA. Wide ranges of all observed traits indicated a high diversity of the tested accessions. Principal component analysis revealed very large diversity within individual countries, especially within Mali and Burkina Faso. Some limited grouping of accessions from Niger, Senegal, Cameroon, Morocco, and Mauritania was observed for individual principal component axes. Geographical differentiation and country differences were detected for several traits. The results and data presented in our study reflect WCA pearl millets’ tremendous diversity and adaptability to a wide range of environments and give a sound basis for breeders to select and utilize this germplasm to serve the manifold needs of WCA pearl millet farmers.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Pearl millet
Pennisetum glaucum
(L.) R. Br. is an important food-security crop to smallholder farmers in West Africa (WA). Breeding for high yield and stability is a major challenge in the harsh ...environments of WA but could be tackled by a more systematic exploitation of hybrid vigor and heterosis in breeding of both open-pollinated varieties (OPVs) and different types of hybrids. Knowledge of combining ability patterns and quantitative-genetic parameters is required for an efficient development of hybrid vigor and heterosis in breeding programs. Hence, our objectives were to complement other existing studies and estimate the combining ability of seven unique, highly diverse Sahelian pearl millet populations from Senegal, Mali, Benin, Burkina Faso, Niger, Sudan and Nigeria and the heterosis and stability of their 42 diallel-derived population hybrids (or hybrid populations) to inform pearl millet OPV and hybrid breeding. The materials were evaluated in six environments in WA in 2007. Grain yield (GY) exhibited an average panmictic mid-parent heterosis of 24%, ranging from − 1.51 to 64.69%. General combining ability (GCA) was significant across test environments as reflected by high heritability estimates and high GCA:SCA variance ratios. Thus, early selection for parental per se performance would be rewarding. The parental population from Sudan (IP8679) had strongly negative GCA for GY. Its lack of adaptation contributed to the predominance of additive effects in the present germplasm set. Parental populations PE02987 (Senegal), PE05344 (Mali) and ICMV IS 92222 (Niger) showed large positive GCA for GY. Their offspring, especially PE02987 × PE05344 and Kapelga × ICMV IS 92222, exhibited a high and stable GY across all test environments. Tapping the regional pearl millet genetic diversity and preselecting the crossing parents seem beneficial for OPV and hybrid breeding to increase pearl millet productivity in WA.
•Adapted pearl millet hybrids could contribute to food security in West Africa (WA).•Heterosis in population hybrids indicated great potential for hybrid breeding in WA.•Hybrids based on ...inter-country crosses did not differ from intra-country crosses.•Lack of natural heterotic groups requires systematic combining ability studies.
Pearl millet (Pennisetum glaucum (L.) R. Br.) is an important hybrid crop in India. However, to date limited pearl millet hybrid development has been undertaken in West Africa (WA), which is the center of pearl millet origin and diversity and where this crop is most important outside India. Using a diverse set of WA pearl millet germplasm, objectives of this study were to determine the superiority of population hybrids over open-pollinated varieties for agro-morphological and agronomic traits in WA pearl millet germplasm; and (ii) to derive strategies for pearl millet hybrid breeding in WA, based on quantitative-genetic parameters, combining ability and heterotic patterns among geographically close versus distant pearl millet populations. A 10×10 factorial mating design was performed with four parental OPVs from each of five WA countries. The 100 population hybrids and their parents were tested for 14 traits at six locations in one year, thereby using contrasting locations to indirectly sample the rainfall variability inherent to WA pearl millet production environments. Grain yield showed an average panmictic midparent heterosis (PMpH) of 16.7%, ranging from −26 to 73%. The mean grain yield of hybrids based on inter-country crosses did not differ significantly from intra-country crosses. Geographic distance between parents was positively correlated with hybrid grain yield (r=0.31), but not with PMpH . Some crosses between accessions from Niger/Nigeria and Senegal were outstanding. Predictability of population hybrid performance for grain yield was moderate based on midparent values (r=0.43) and slightly better based on general combining ability (GCA) (r=0.56). Overall, pearl millet hybrid breeding in WA seems very promising, but there do not seem to be clear “natural” heterotic groups among WA pearl millet landraces. Such heterotic groups as the basis of sustainable hybrid breeding need rather to be created systematically, by building on existing combining ability patterns and aiming to maximize combining ability between the groups.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Pearl millet (Pennisetum glaucum (L.) R. Br., syn. Cenchrus americanus (L.) R. Br) is an important cereal and fodder crop in hot and arid environments. There is great potential to improve pearl ...millet production through hybrid breeding. Cytoplasmic male sterility (CMS) and the corresponding nuclear fertility restoration / sterility maintenance genes (Rfs) are essential tools for economic hybrid seed production in pearl millet. Mapping the Rf genes of the A
CMS system in pearl millet would enable more efficient introgression of both dominant male-fertility restoration alleles (Rf) and their recessive male-sterility maintenance counterparts (rf).
A high density linkage map based on single nucleotide polymorphism (SNP) markers was generated using an F
mapping population and genotyping-by-sequencing (GBS). The parents of this cross were 'ICMA 02777' and 'ICMR 08888', which segregate for the A
Rf locus. The linkage map consists of 460 SNP markers distributed mostly evenly and has a total length of 462 cM. The segregation ratio of male-fertile and male-sterile plants (3:1) based on pollen production (presence/absence) indicated monogenic dominant inheritance of male-fertility restoration. Correspondingly, a major quantitative trait locus (QTL) for pollen production was found on linkage group 2, with cross-validation showing a very high QTL occurrence (97%). The major QTL was confirmed using selfed seed set as phenotypic trait, though with a lower precision. However, these QTL explained only 14.5% and 9.9% of the phenotypic variance of pollen production and selfed seed set, respectively, which was below expectation. Two functional KASP markers were developed for the identified locus.
This study identified a major QTL for male-fertility restoration using a GBS-based linkage map and developed KASP markers which support high-throughput screening of the haploblock. This is a first step toward marker-assisted selection of A
male-fertility restoration and male-sterility maintenance in pearl millet.
Full text
Available for:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
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