Untangling the hedge: Genetic diversity in clonally and sexually transmitted genomes of European wild roses, Rosa L.

While European wild roses are abundant and widely distributed, their morphological taxonomy is complicated and ambiguous. In particular, the polyploid Rosa section Caninae (dogroses) is characterised by its unusual meiosis, causing simultaneous clonal and sexual transmission of sub-genomes. This hemisexual reproduction, which often co-occurs with vegetative reproduction, defies the standard definition of species boundaries. We analysed seven highly polymorphic microsatellite loci, scored for over 2 600 Rosa samples of differing ploidy, collected across Europe within three independent research projects. Based on their morphology, these samples had been identified as belonging to 21 dogrose and five other native rose species. We quantified the degree of clonality within species and at individual sampling sites. We then compared the genetic structure within our data to current rose morpho-systematics and searched for hemisexually co-inherited sets of alleles at individual loci. We found considerably fewer copies of identical multi-locus genotypes in dogroses than in roses with regular meiosis, with some variation recorded among species. While clonality showed no detectable geographic pattern, some genotypes appeared to be more widespread. Microsatellite data confirmed the current classification of subsections, but they did not support most of the generally accepted dogrose microspecies. Under canina meiosis, we found co-inherited sets of alleles as expected, but could not distinguish between sexually and clonally inherited sub-genomes, with only some of the detected allele combinations being lineage-specific

Recent Large-Scale Genotyping and Phenotyping of Plant Genetic Resources of Vegetatively Propagated Crops

Several recent national and international projects have focused on large-scale genotyping of plant genetic resources in vegetatively propagated crops like fruit and berries, potatoes and woody ornamentals. The primary goal is usually to identify true-to-type plant material, detect possible synonyms, and investigate genetic diversity and relatedness among accessions. A secondary goal may be to create sustainable databases that can be utilized in research and breeding for several years ahead. Commonly applied DNA markers (like microsatellite DNA and SNPs) and next-generation sequencing each have their pros and cons for these purposes. Methods for large-scale phenotyping have lagged behind, which is unfortunate since many commercially important traits (yield, growth habit, storability, and disease resistance) are difficult to score. Nevertheless, the analysis of gene action and development of robust DNA markers depends on environmentally controlled screening of very large sets of plant material. Although more time-consuming, co-operative projects with broad-scale data collection are likely to produce more reliable results. In this review, we will describe some of the approaches taken in genotyping and/or phenotyping projects concerning a wide variety of vegetatively propagated crops

Fyra nya äpplesorter från Balsgård

Fakulteten för landskapsarkitektur, trädgårds- och växtproduktionsvetenskap 2014 För SLU är frukt och bärförädling en viktig verksamhet som bedrivs på Balsgård, 10 km norr om Kristianstad i nordöstra Skåne (Nybom 2006, 2010). Innan SLU kom in i bilden 1970, hade äppleförädling bedrivits på Balsgård genom Föreningen för växtförädling av frukt och bär sedan 40-talet. Balsgård är beläget i ett av landets äldsta frukt- odlingsdistrikt, vilket lämpar sig utmärkt för äppleträd. Här finns lätta och varma jordar samt gynnsamma odlingslägen på sluttningar ner mot sjöarna som ligger tätt i det mjukt böljande landskapet. Den första äpplesorten från Balsgård blev Alice, som lanserades i slutet av 60-talet (Nybom 2012c). Denna följdes snart av storsäljare som Aroma och Katja, samt den synnerligen vinterhärdiga Rödluvan. På senare tid är det främst de välsmakande och sjukdomsresistenta syskonsorterna Frida och Fredrik som låtit tala om si

The Systematics, Reproductive Biology, Biochemistry, and Breeding of Sea Buckthorn—A Review

Both the fruit flesh and seeds of sea buckthorn have multiple uses for medicinal and culinary purposes, including the valuable market for supplementary health foods. Bioactive compounds, such as essential amino acids, vitamins B, C, and E, carotenoids, polyphenols, ursolic acid, unsaturated fatty acids, and other active substances, are now being analyzed in detail for their medicinal properties. Domestication with commercial orchards and processing plants is undertaken in many countries, but there is a large need for improved plant material with high yield, tolerance to environmental stress, diseases, and pests, suitability for efficient harvesting methods, and high contents of compounds that have medicinal and/or culinary values. Applied breeding is based mainly on directed crosses between different subspecies of Hippophae rhamnoides. DNA markers have been applied to analyses of systematics and population genetics as well as for the discrimination of cultivars, but very few DNA markers have as yet been developed for use in selection and breeding. Several key genes in important metabolic pathways have, however, been identified, and four genomes have recently been sequenced

Flera nya utländska äppelsorter har bra kvalitet men är känsliga för sjukdomar

Odlarna vill ha nya sorter med bättre egenskaper, som gör det möjligt att bedriva hållbar och konkurrenskraftig odling av kvalitetsfrukt i Sverige. I detta faktablad sammanfattas resultat från två projekt med syftet att utvärdera odlings- och kvalitetsegenskaper hos några dessert- och mustäpplesorter, som nyligen tagits fram genom växtförädling

Många cideräppelsorter är känsliga för skorv men ger unik arom

I Sverige finns ingen tradition av att odla cideräpplen men intresset för att tillverka lokal cider har ökat markant under senare år. I detta faktablad sammanfattas resultat från två projekt som genomförts för att utvärdera och introducera nya cideräpplesorter för odling och vidareförädling i Sverige

Review of the Impact of Apple Fruit Ripening, Texture and Chemical Contents on Genetically Determined Susceptibility to Storage Rots

Fungal storage rots like blue mould, grey mould, bull's eye rot, bitter rot and brown rot destroy large amounts of the harvested apple crop around the world. Application of fungicides is nowadays severely restricted in many countries and production systems, and these problems are therefore likely to increase. Considerable variation among apple cultivars in resistance/susceptibility has been reported, suggesting that efficient defence mechanisms can be selected for and used in plant breeding. These are, however, likely to vary between pathogens, since some fungi are mainly wound-mediated while others attack through lenticels or by infecting blossoms. Since mature fruits are considerably more susceptible than immature fruits, mechanisms involving fruit-ripening processes are likely to play an important role. Significant associations have been detected between the susceptibility to rots in harvested fruit and various fruit maturation-related traits like ripening time, fruit firmness at harvest and rate of fruit softening during storage, as well as fruit biochemical contents like acidity, sugars and polyphenols. Some sources of resistance to blue mould have been described, but more research is needed on the development of spore inoculation methods that produce reproducible data and can be used for large screenings, especially for lenticel-infecting fungi

DNA fingerprinting demonstrates extremely low levels of genetic variation among blackberry cultivars grown in Finland

Most blackberry plants cultivated in Finland closely resemble the American species Rubus allegheniensis. Thirty nine such blackberry accessions in the University of Helsinki clone collection were studied by hybridization-based DNA fingerprinting and compared with some known cultivars of R. allegheniensis derivation. ‘lmperial’ appears to be identical to the old cultivar ‘Majestät’, but ‘Earliest of All’ differs considerably. In addition, 37 of the accessions analysed also have DNA fingerprints that appear to be completely identical to that of ‘Majestät’! The remaining two accessions, although identical to each other, exhibit one band not found in ‘Majestät’ that is probably caused by a somatic mutation

'Svenska' plommon på Balsgård

Om vi säger ’Viktoria’ så tänker du kanske inte bara på en prinsessa utan även på ett mycket omtyckt plommon? Vackert och välsmakande, precis som många andra plommonsorter här i landet. En del av de äldre plommonsorterna återfinns fortfarande i många hemträdgårdar medan de nyare sorterna främst förekommer i yrkesodlingar