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Fusarium head blight (FHB) and the mycotoxins produced by its causal agents in oats (Avena sativa L.) have become a growing problem in northern countries over the last decades. The development of resistant cultivars would offer a highly needed and economical solution to the problem. To tackle the high genotype×environment interaction of FHB, a combined analysis was carried out on eight greenhouse and 13 field experiments inoculated with DON-producing Fusarium species. Our data included 406 oat genotypes consisting of Nordic cultivars, breeding lines and potentially resistant gene bank accessions. High variation in the DON accumulation estimates in the material shows that the selection of genotypes with better resistance would be valuable. The greenhouse and field studies resulted in significantly different oat genotype susceptibility rankings for both DON and Fusarium infected kernels. The results obtained from the field experiments have more practical relevance for farmers and breeders for the identification of DON resistant cultivars than greenhouse screenings. Days to maturity and the plant height of the genotypes both significantly affected the Fusarium infections and DON in the field. The relationship between Fusarium infected kernels, DONand germination capacity provide an insight into the composition of genotypes with resistance. The core set of 30 oat genotypes, which were phenotyped in several experiments, provides valuable examples of both highly susceptible and moderately resistant oat genotypes.

Fusarium head blight (FHB) and the accumulation of deoxynivalenol (DON) mycotoxin induced by Fusarium graminearum and other Fusarium fungi cause serious problems for oat production in the Nordic region (Scandinavia, Fennoscandia). Besides toxin accumulation, FHB causes reduction in grain yield and in germination capacity. Here, genomic approaches for accelerating breeding efforts against FHB and DON accumulation were studied. Resistance-related traits included DON content, F. graminearum DNA (relative to oat DNA) content (qFUSG) measured with real-time quantitative polymerase chain reaction (PCR), Fusarium-infected kernels (FIKs) and germination capacity (GC). Plant germplasm used in the study consisted of mostly breeding lines, and additionally, a few cultivars and exotic accessions. Genome-wide association study (GWAS) and genomic prediction, enabling genomic selection (GS) on the resistance-related and collected agronomic traits, were performed. Considerable genetic correlations between resistance-related traits were observed: DON content had a positive correlation (0.60) with qFUSG and a negative correlation (&minus, 0.63) with germination capacity. With the material in hand, we were not able to find any significant associations between markers and resistance-related traits. On the other hand, in genomic prediction, some resistance-related traits showed favorable accuracy in fivefold cross-validation (GC = 0.57). Genomic prediction is a promising method and genomic estimated breeding values (GEBVs) generated for germination capacity are applicable in oat breeding programs.

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Solanum acaule Bitt., a wild potato species, is closely related to cultivated potato (Solanum. tuberosum L.). Incorporation of desirable traits from allotetraploid [2n=4x=48, 2 endosperm balance number (EBN)] S. acaule (acl) into autotetraploid (2n=4x=48, 4EBN) S. tuberosum (tbr) is difficult due to incongruity boundaries. In this study, three hybrid combinations, each with a specific genome constitution, were produced through protoplast fusion: (1) hexaploid 2x acl (+) 4x tbr, (2) tetraploid 2x acl (+) 2x tbr, and (3) hexaploid 4x acl (+) 2x tbr hybrids. In terms of glycoalkaloid aglycones, the hybrids produced demissidine, tomatidine and solanidine, similarly to the S. acaule parental species, but S. tuberosum synthesised only solanidine. Inoculations with Clavibacter michiganensis ssp. sepedonicus (Cms), which is the causal agent of bacterial ring rot in potato, yielded significantly lower total glycoalkaloid aglycone accumulation both in S. acaule plants and in interspecific hybrids in comparison with the corresponding mock-inoculated plants. However, in S. tuberosum the aglycone levels were either higher or unchanged as a result of infection by Cms. To incorporate the desirable traits of the interspecific somatic hybrids into 4EBN S. tuberosum, sexual backcrosses were carried out. The hexaploid 4x acl (+) 2x tbr hybrids with the hypothetical 4EBN showed the greatest capacity to undergo backcrosses with S. tuberosum.

Protoplasts were fused to produce somatic hybrids between a triploid (2n=3x=32-34) interspecific somatohaploid betweenSolanum brevidens Phil. andS. tuberosum L., and a dihaploid (2n=2x=24) anther-derived line ofS. tuberosum cv. Van Gogh. A total of 265 plants were regenerated from protoplast fusion derived calli and their hybridity was verified using fusion partner specific RAPD markers. These “second generation” somatic hybrids were aneuploid pentaploids (2n=5x=51-65) with a 2C DNA content ranging from 3.36 to 4.43 pg, which corresponded to the sum of the 2C values of each of the fusion partners (somatohaploid: 2.22 pg; and the dihaploid line of cv. Van Gogh: 1.87 pg). Most of the “second generation” somatic hybrids were vigorous, but variable in morphology. They were extremely resistant to PLRV and they had tolerance to PVY infection derived from the somatohaploid fusion partner. Even though most of the “second generation” hybrids tuberized, the tuber morphology was variable and most were poorly shaped. InErwinia soft rot resistance tests, the tubers showed higher level of resistance than the tetraploidS. tuberosum cultivars, the dihaploidS. tuberosum fusion partners and the hexaploid somatic hybrids betweenS. brevidens andS. tuberosum. The “second generation” somatic hybrids were all male sterile and failed to produce berries or seeds.

Solanum acaule Bitt. is a disomic tetraploid (4x) wild potato species which is resistant to several potato diseases. Introgression of disease resistance and abiotic stress tolerance to the tetrasomic tetraploid (4x) cultivated potato (S. tuberosum L.) gene pool via crossing has been limited due to the difference in the endosperm balance number. In the present study, protoplast fusion was applied to produce hexaploid (6x) somatic hybrids between the parental lines, tetraploid (4x) S. acaule and two anther-derived dihaploid (2x) lines of S. tuberosum cv. White Lady. One callus (0.4%) of a total of 229 calli obtained regenerated into shoots in the fusion combination S. acaule (+) White Lady 15.dh.8.2.2. All the regenerated shoots were confirmed to be interspecific somatic hybrids using species-specific RAPD markers. In another fusion combination, S. acaule (+) White Lady 7.dh.23.1.1, fifteen calli (5%) regenerated into a total of sixteen shoots from 289 calli. All the analysed somatic hybrids between S. acaule and S. tuberosum were hexaploid. The mean DNA content (2C value) of the combination S. acaule (+) White Lady 15.dh.8.2.2 somatic hybrids (4.55 pg), was approximately the sum (4.69 pg) of the DNA contents of the parental lines, S. acaule (2.95 pg) and S. tuberosum (1.74 pg). In the greenhouse, the two somatic hybrids analysed were normal in their morphological characteristics and more vigorous than their parental lines. Most of the morphological characteristics were closer to the tetraploid S. acaule than to the dihaploid S. tuberosum. The interspecific somatic hybrids are currently being tested for frost tolerance and glycoalkaloid composition.

Somatic hybrids of anther-derived dihaploid (2x) potato (Solanum tuberosum L.) lines were produced by electrofusion of protoplasts. Using RAPD (randomly amplified polymorphic DNA) markers, six new combinations of dihaploid parental lines from cultivars Matilda, Nicola, Pito, Stina, Van Gogh and White Lady were identified. RAPD marker identification of the putative hybrids was mostly done using two distinct parental line specific primers. 43% of the 76 regenerated calli from the six combinations produced hybrid shoots. Most of the somatic hybrids were tetraploid (4x), but in four fusion combinations plants of hexaploid (6x), octoploid (8x) or mixoploid level were also identified by chromosome counts or flow cytometric nuclear DNA analysis. The mean nuclear DNA content (2C value) of the tetraploid and hexaploid somatic hybrids was lower than the expected DNA content (i.e. the 2C values of the original tetraploid cultivars or the sum of the 2C values of the dihaploid fusion parents). Some somatic hybrids having the expected nuclear DNA content were also found., Protoplasteilla tarkoitetaan soluja, joiden solunseinä on poistettu entsymaattisesti. Tällaisia soluja voidaan fuusioida yhteen, jolloin kahden eri perunalinjan yhdistelmästä muodostuu solujen kasvatuksen jälkeen somaattisia hybridejä. Somaattiset hybridit ovat perunan jalostukselle tärkeitä, koska tavanomainen jalostus, joka tapahtuu tetraploidien (4x) kasvien suvullisin risteytyksin, tarvitsee runsaasti risteytyksiä ja suuren määrän jälkeläisiä. Käyttämällä hyväksi dihaploideja (2x) perunoita ja fuusioimalla linjoja yhteen (2x + 2x), voidaan perunan jalostusta sekä nopeuttaa että tehostaa. Tässä työssä ponsiviljelyllä tuotetuista dihaploideista perunalinjoista (peräisin lajikkeista Matilda, Nicola, Pito, Stina, Van Gogh ja White Lady) eristettiin protoplasteja, joita fuusioitiin sähköisesti. Kahden eri dihaploidin protoplasteja fuusioimalla saatiin tuotettua somaattisia hybridejä. Saadut kuusi uutta fuusioyhdistelmää analysoitiin käyttämällä RAPD-merkkejä. Oletetut hybridit määritettiin useimmiten kahdella alukkeella, jotka kumpikin tuottivat dihaploideille vanhempaislinjoille spesifisen merkin. Useimmat tuotetut somaattiset hybridit olivat tetraploideja (4x), mutta neljästä fuusioidusta yhdistelmästä muodostui myös kasveja, joilla oli joko heksaploidinen (6x), oktoploidinen (8x) tai miksoploidinen genomi. Tämä tutkittiin laskemalla hybridien kromosomit tai analysoimalla kasvit virtaussytometrillä. Somaattisten hybridien DNA-pitoisuuksien oletettiin olevan yhtä suuria kuin tetraploidien perunoiden DNA-pitoisuudet tai dihaploidien fuusiovanhempien DNA-pitoisuuksien summat. Kuitenkin useiden tetra- ja heksaploidien hybridien DNA-pitoisuuksien keskiarvot olivat pienempiä kuin oletetut DNA-pitoisuudet.

In 1987, a potato research project called “Minimized use of chemical inputs in potato production” was started in all five Scandinavian countries. In this paper, the results of one field trial series carried out at the Potato Research Institute, Lammi, Finland, during the years 1987–90 are reported. The main plots in a split-plot designed trial series consisted of three cropping systems: conventional, integrated and organic. The subplots included three cultivars differing especially in their late blight (Phythophtora infestans, (Mont.) de Bary) resistance: Bintje, Record and Matilda. Canopy measurements showed differences that can be attributed to different nitrogen supply in decreasing order from conventional to integrated to organic system. The trial sites were very heavily infested with potato scab, resulting in a very low percentage of I-class yield in susceptible cultivars Bintje and Matilda. Late blight was a serious problem in organically grown Bintje, as expected. Total yields in the integ...

Steroidal glycoalkaloids (SGAs) are produced following the general steroid biosynthesis pathway, starting from acetyl-coenzyme A and followed by the intermediates mevalonic acid, squalene, cycloartenol, and cholesterol. α-Chaconine and α-solanine are the main SGAs of the cultivated potato (Solanum tuberosum), whereas many other SGAs are known in the wild potato species. Low concentrations of SGAs improve the taste of potato, but concentrations greater than 200 mg/kg can have toxic effects on animals and humans. SGAs have antimicrobial activity and confer resistance to some insects, but many such pests of potato are not greatly affected. Certain environmental conditions and wounding enhance SGA accumulation in tubers in the field and storage. Low production of SGAs is a dominant character inherited in a relatively simple manner and can be selected for in potato-breeding programs, whereas the use of wild potato germplasm tends to increase the SGA accumulation in the breeding lines. Further efforts ...

A total of 1000 anther-derived plants was regenerated from tetraploid potato (Solanum tuberosum L.) genotypes. Capacity to undergo androgenesis was analysed in 41 potato cultivars and 7 clones grown either in the greenhouse or in the field. Of the 48 genotypes, 33 produced embryos and 23 regenerated shoots from embryos. Anther-derived plantlet production was determined in genotypes 86110, Agria, Calgary, Escort, Helios, Idole, JO 0982 JO 1432, Kainuun Musta, Kardal, KE48, Matilda, Nicola, Petra, Pito, Rustica, Stirling, Torridon, Ute, Van Gogh, Vebeca, Vento and White Lady. The highest number of shoots (24 shoots/100 anthers) was obtained from cv. Calgary, when anthers were isolated from field-grown donor plants. Incubating anthers at 28 C, rather than at 20 C or 24 C, enhanced embryo production in four genotypes tested. However, shoot production was improved only in cv. Pito cultured at 28 C. When anthers of cv. Petra were cultured at 28 C for four weeks, followed by reduction of culture temperature to 24 C, a high rate of shoot production was recorded (14 shoots/100 anthers). The ratio between dihaploids and tetraploids varied among the anther-derived plants of the different genotypes. The number of dihaploids was highest in potato clone JO1432 (100%) and in cv. Calgary (93%) and lowest in cvs. Pito (21%) and Torridon (6%).

Pollination experiments were carried out on ulluco (Ullucus tuberosus), known as a very poor seed producer. All the clones used were diploids. The effect of self-vs. cross-pollination was studied in Experiment 1. Caged selfpollinated flowers produced no seeds. Different clones produced seeds in 0–8% of caged cross-pollinated flowers and in 5–19% of cross-pollinated non-caged flowers. Ulluco is thus basically an outbreeder.

Ulluco (Ullucus tuberosus) is a vegetatively propagated crop plant that flowers abundantly but sets only few seeds. We examined if the low seed/ovule ratio can be explained by morphological abnormalities in ovules, embryo sacs or embryos. In 35 clones growing in the actual area of cultivation in Ecuador and in 5 clones grown in Finland flowers were analysed by clearing technique. About half of all analysed clones contained ovules and embryo sacs whose development was arrested, in two clones there were embryo sacs whose cell patterns were abnormal and in four clones there were double embryo sacs. There were both normal and abnormal ovules and embryo sacs in the same plant. Genetic load is suggested to be one of the causes for the low sexual fertility found in ulluco. It may be incapable of maintaining homeostasis of development of the ovule and embryo sac in a varying environment. The occurrence of developmental abnormalities should be studied in each clone intended for inclusion in traditional breeding programmes.

Kauran lajikejalostuksella pyritään tuottamaan entistä satoisampia ja laadukkaampia lajikkeita. Bioteknisiä menetelmiä hyödyntämällä mahdollisuudet vastata rehu- ja elintarviketeollisuuden sekä viljelijöiden toivomuksiin paranevat. Kauran (Avena sativa L.) molekyyligeneettinen tutkimus on kehittynyt hitaasti verrattuna maailmanlaajuisesti tärkeämpiin viljalajeihin. Koska Suomi on kansainvälisesti suuri kaurantuottajamaa, on kilpailukykyisten lajikkeiden tuottaminen tärkeää. Tässä hankkeessa kehitettiin ja sovellettiin biotekniikan menetelmiä kotimaisen kauranjalostuksen tueksi. Tutkittaviksi ominaisuuksiksi valittiin kauran sisältämä terveysvaikutteinen ravintokuitu β-glukaani, rehun energia-arvon kannalta tärkeä öljypitoisuus ja viime vuosina Suomeen levinnyt kauran lehtilaikkutauti. Tutkimuksessa koottiin yli kuusisataa DNA-merkkiä käsittävä geenikartta käyttäen pohjoismaista kauran risteytysjälkeläistöä, joka oli muokattu solukkoviljelyssä haploidiavaiheen avulla täysin yhtenäisiksi DH-linjoiksi. Kartan avulla paikannettiin tutkittuihin ominaisuuksiin vaikuttavia geenejä. Tutkimuksessa löydettiin muun muassa seitsemän öljypitoisuuteen, kaksi β-glukaaniin ja monta lehtilaikkutautiin vaikuttavaa kromosomialuetta. Lisäksi kartoitettiin viljelyominaisuuksiin vaikuttavia geenejä. Ominaisuuteen vaikuttavan geenin lähellä sijaitsevia DNA-merkkejä voidaan käyttää näiden ominaisuuksien merkkiavusteisessa valintajalostuksessa. Haploidijalostustekniikat ja DNA-merkkiavusteinen valintajalostus ovat tämän päivän kauranjalostuksen ulottuvilla. Tulevaisuudessa nopeasti kehittyvät, koko genomin tutkimuksen eli genomiikan menetelmät tarjoavat lisävälineitä kaurankin ominaisuuksien periytymisen ymmärtämiseen ja jalostukseen.

Ulluco, Ullucus tuberosus, is a tuber crop plant with a reduced ability to produce botanical seed. This paper discusses problems related to the botanical seed set of ulluco. Ten clones of this species were studied, and the number of seeds per plant was recorded. Enhancement of seed production was attempted by the application of three growth regulators; gibberellic acid, CCC, and a synthetic cytokinin, 6-benzylamine purine. Seed set ability was shown to vary between the clones, and the application of plant growth regulators did not enhance seed production. Variation in fruit weight was observed. Because of genetic variation between clones in their ability to set seed, it is proposed that there is a possibility of breeding ulluco using botanical seeds. However, methods for improving the yield of botanical seed need to be developed.

The paper deals with variations in enzyme pattern in the seeds of ulluco, Ullucus tuberosus. Six seeds per clone, four clones and three enzyme systems (malate dehydrogenase, glutamate oxaloacetate transaminase and 6-fosfoglucose dehydrogenase) were examined. There was variation in enzyme pattern between the seeds of a single clone. It is concluded that ulluco is not an apomictic species but a truly sexual one. Consequences of these findings for breeding programmes of ulluco are pointed out.

The Finnish collections of Graeco-Roman pottery result mostly from haphazard acquisitions since the beginning of the nineteenth century, and are in only a very few cases the fruits of systematic collection. As, for almost two centuries, the tradition of classical archaeology in Finland has depended on the interest of private individuals, it is no wonder that only two objects in the present CVA volume are previously published.The CVA Finland, fascicule 1 thus fills a major scholarly and museological gap. The study and publication of these vases aims to dispel their anonymity, conveying them to anyone interested in Greek and Roman pottery.

Summary The fruit of the cultivated ulluco (Ullucus tuberosus Loz.) has been referred to in the literature either as non-existing or as a berry, seldom as a dry fruit. The fruit of this species as well as the genus is described here for the first time, and is shown to be a dry and indehiscent nutlet of an obovate shape and bilaterally symmetrical cross-section. The thin testa of the seed is immediately inside the thickened fruit wall. The embryo is strongly curved and encircles the relatively scanty perisperm.

Material of 229 clones of ulluco (Ullucus tuberosus), representing 10 accessions from markets in southern Peru and one from the wild in Bolivia, was analyzed with regard to morphological variation. The diploid chromosome number (2n = 24) was ascertained in 16 of the clones. Clones grown in different environments (e.g., long vs. short day) retained a more or less similar order of variation with respect to color of the tubers, stems, and leaves and the length/width ratio of the leaves. The shape of fully developed tubers also showed stable variation. Within a single experiment several other vegetative characters showed significant differences between accessions. Furthermore, many flower and inflorescence characters showed variation between accessions, some of them also indicating geographical variation between the Puno-Juliaca area and the Cuzco area. Considerable variation between the clones of an accession was evident, some accessions being clearly more variable than others. Our results show that ulluco is a crop plant that varies extensively even within a geographically limited area. Although repeatedly referred to in the literature as a purely asexual crop, ulluco was shown to be capable of sexual reproduction; this must have been and possibly still is an important source of genetic variation in the species.