Accurate assessments of genetic gains ensuing from plant breeding for the most important agronomic characteristics in Nordic spring barley ( Hordeum vulgare L.) are not available. Hence this research was aimed to determine the rate of genetic improvement in the Nordic barley breeding pool. This study included 90, 2-row spring barley cultivars released (1942–1988) and29, 6-row spring barley cultivars released(1930–1991) adopted by Nordic farmers that were tested in four Nordic locations for three consecutive years. Relative genetic gain owing to plant breeding was 13% in2-row barley and 34% in 6-row barley for grain yield. The absolute gain for this characteristic was 13 ± 3 kg ha -1 year -1 in 2-row barley, and22 ± 3 kg ha -1 year -1 in6-row barley. Improved yield was achieved in Nordic barley by reducing plant height(0.20 ± 0.04 cm year -1 for 2-rowbarley and 0.16 ± 0.06 cm year -1 for 6-row cultivars), thereby reducing significantly lodging (0.5 ± 0.1%year -1 and 0.4 ± 0.1year -1 ), and increasing significantly the harvest index (0.0008 ± 0.0002year -1 and 0.0018 ± 0.0002year -1 ). Additionally, in 2-row spring barley cultivars resistance to powdery mildew (0.19 ± 0.08% year -1 )and thousand-kernel weight (0.07 ±0.03 g year -1 ) were also significantly enhanced, whereas hectoliter weight was improved (0.06 ± 0.02 kg year -1 )in 6-row barley cultivars in the period investigated.

A phenotypic diversity index (PDI) was calculated using 10 agronomiccharacteristics recorded in 90 accessions of 2-row spring barleys and 29accessions of 6-row spring barleys grown in the Nordic Region. The PDIranged from 0.0308 to 0.6245 in 2-row barley accessions and from0.0314 to 0.7016 in 6-row barley accessions. The average PDIs were0.2178 and 0.2438 in 2-row and 6-row barley germplasm, which confirmsthat some older cultivars were parents of newer cultivars. The lowest PDIwas between accessions with the same name, which suggest that irrespectiveof their market source, they were the same cultivars. The largest PDI rangesin 2-row barley cultivars within the same country or release decade werecorrelated to the number of accessions in the respective cluster, whichsuggests that phenotypic diversity in this germplasm depends on the numberof cultivars included in the cluster. However, this association was not alwaysobserved in 6-row barley cultivars. The most distinct 2-row cultivars wereArla and Akka from Sweden, whereas Sigur and Tampa from Iceland werethe most distinct 6-row cultivars as determined by both PDI and averagelinkage cluster analysis. This analysis also confirm that the 2-row barleyaccessions Jenny, Triumph, and Vega, which were obtained from twodistinct market sources, and the 6-row barley accessions under the nameAgneta (but from three market sources) were the same. The analysis ofvariance of the PDI indicates that 6-row germplasm may be clusteredaccording to their geographical origin or decade of release, but this was notobserved in 2-row barley germplasm. This research demonstrates theadvantage of PDI to assess variation among breeding pools.

Variation in agronomic and quality characteristics was investigated in 220 Nordic spring barley cultivars across distinct environments (6 locations during 3 years) in the Nordic Region of Europe. The objectives of this research were to determine the importance of the genotype by environment interaction in all characteristics evaluated and to establish the relationship among different stability statistics for grain yield. Combined analysis of variance across locations indicated that both environments and genotype by environment interactions influenced significantly the cultivar phenotypes for all characteristics, irrespective of their type (row number) or earliness. The first two interaction principal component axes of the additive-main-effects-and-multiplicative-interaction (AMMI) model accounted together between 35% and 75% of the total genotype-by-environment interaction for all characteristics. Grain yield was, on average, higher in 2-row than in 6-row cultivars, which were significantly earlier in heading and grain maturity than the former. However, in some of the most northern locations, 6-row barley cultivars significantly outyielded on average 2-row barley lines. The genotype by location interaction variance (σ2 GL) accounted by each genotype was significantly associated to the deviation from regression (Tai's λ) while the coefficient of regression (β) was significantly correlated to the IPCA1 and IPCA2 of the AMMI model in 2-row, 6-row and early barley cultivars.

Diallel mating designs have proved informative in determining the inheritance of quantitative traits of interest to plant breeders. Apart from the well-established analyses of a complete diallel, the two-way factorial data structure of this design lends itself to analysis by the additive-main-effects-and-multiplicative-interaction (AMMI) model. This research article describes the joint application of the AMMI model and Griffing’s method 1, model I, to gain insight into the breeding value of inbred lines in a self-pollinated crop such as disomic, hexaploid bread wheat. Data from a multi-environment trial of a complete diallel cross between eight lines adapted to the East African highlands were analyzed to provide an example of this joint analysis. This combined approach identified not only the direction of a cross, i.e. which parent should be male or female, but also which crosses produce offspring showing F 1 heterosis.

Several genotype-by-environment stability measures are in use, but little information exists about their inheritance or genetic inter-relationships. Among those measures in common use are the linear regression coefficient (b), deviations from regression (s b ), coefficient of determination (R 2 ), coefficient of phenotypic variation (CPV) and, more recently, interaction principal components (IPCA) of the additive-main-effect-and-multiplicative-interaction (AMMI) model. Because of the factorial structure of the data, the diallel cross is well suited to study these parameters and their relationship to quantitative traits. For this study a complete diallel cross, derived by mating eight lines from a broad based bread wheat breeding population, was grown for several growing seasons at two Ugandan locations, one of which was prone to yellow rust. Stability parameters and grain yield were measured for each cross. CPV had the highest narrow-sense heritability (h 2 =0.522) followed by IPCA1 of the AMMI (h 2 =0.461). Lowest narrow-sense heritabilities were calculated for b and R 2 (h 2 =0.150 and 0.100 respectively). There were high additive genetic correlations (r A ) between grain yield and CPV (r A =−0.933), grain yield and IPCA1 (r A =0.707), and grain yield and IPCA2 (r A =0.751). The genetic association between CPV and IPCA1 was also high and negative (r A = −0.934). These results suggest that it may be possible to select simultaneously for high and stable grain yield in this broad-based bread wheat breeding pool by selecting outyielders that exhibit a low CPV.

An efficient Agrobacterium-mediated transformation procedure for barley was developed for immature embryos. Factors considered crucial for the delivery and integration of transgenes, such as type of growth regulator, duration of preculture period, plasmolysis and micro wounding were evaluated for their effect on frequencies of transient expression and stable integration. Dicamba in the callus induction and maintenance media was generally superior to 2,4-D in promoting transient expression and subsequent stable transformation. Plasmolysis generally reduced the level of transient expression although transgenic plants were recovered when 1-day precultured embryos were plasmolysed and grown on 2,4-D containing media. Micro wounding by particle bombardment did not change the level or localisation of transient expression events after Agrobacterium infection. Transgenic plants were generated with five out of 12 different procedures with transformation efficiencies ranging from 1.7 to 6.3%. Integration of bar and uidA coding sequences was confirmed by PCR for 75 plants representing 42 independent transgenic lines. Expression of the uidA gene was detected in 74% of primary transformants while 91% of them expressed the bar gene. Southern analysis proved integration of the transgenes with copy numbers ranging from one to six. Most transgenic lines that expressed both marker and reporter genes showed simple integration patterns and Mendelian inheritance of the transgenes in T1 progeny.

Phenotypic diversity for agronomic characteristics was determined in an experiment without fertilizer in 1998 in 41 two-row and 21 six-row winter barley accessions, provided by the Nordic Gene Bank, at Hojbakkegard (Denmark). There were significant differences among these 62 accessions for spring establishment, early flowering, covering, plant height, lodging, tillering, spike length, number of kernels per spike and thousand kernel weight. On average, two-row barley accessions had better establishment, covering and standability (although they were slightly taller) but showed lower tillering than six-row barley accessions. Two-row barley accessions also had larger spikes with fewer kernels, but heavier weight, than six-row barley accessions. There were significant phenotypic correlations among the characteristics scored. However, not all of them were common to two- and six-row barley accessions, which suggests the evolution of distinct genetic systems controlling these associations in the two sets of barley accessions. Average linkage cluster analysis and principal component analysis confirmed number of rows as an important characteristic to discriminate among cultivated barley accessions.

Morphological data recorded from field trials using Citrullus lanatus germplasm collected in Namibia were used to analyse and compare the various morphotypes of this species. The experiment comprised wild types and local landraces as well as commercial cultivars. Cluster analysis supported the indigenous classification system used in Namibia, in which Citrullus types are distinguished based on gross morphology, ecology and usage and grouped into seed, cooking and fresh-eating (watermelon) types. Commercial watermelon cultivars formed a distinct cluster. Wide variation was found within the local types whereas the genetic basis of the commercial type appears to be narrow. The commercial cultivars were most closely related to local watermelon types and more distantly related to the wild types, whereas the cooking melons form an intermediate group.

A Peruvian quinoa core collection, containing 103 chosen ecotypes or landraces, was defined on a geographically stratified non-overlapping sampling procedure. The objective was to determine whether this protocol was correct. Hence, a phenotypic distance matrix among 76 accessions from this core collection was created by calculating the difference between each pair of accessions for each characteristic. These 76 accessions were chosen because they had complete data for eight morphological descriptors. The diversity index was calculated by averaging all the differences in the phenotypic value for each quantitative descriptor divided by the respective range, and considering a matching coefficient for the qualitative descriptors, i.e., 0 for characteristics that matched, and 1 if they did not. The total sum of squares from the analyses of variance for the phenotypic diversity index, based on morphological descriptors, was partitioned between and within Peruvian Departments. The between Department cluster variance was smaller (0.0022) than the within Department cluster variance (0.0144), because accessions with the same stem colour or similar inflorescence type and colour were grouped together irrespective of their Department. This was further corroborated by the average linkage cluster analysis, which was performed on the phenotypic diversity matrix to study the pattern of variation and the relationship between the quinoa landraces of this core subset according to their geographical origin. Within each sub-cluster (based on above qualitative descriptors) accessions were ranked by their Department of collection, which indicated that the sampling method was appropriate for choosing accessions for the Peruvian quinoa core collection.

Nordic plant breeders have selected superior genotypes and released new spring wheat cultivars throughout this century. However, the extent of phenotypic diversity that exists in this improved germplasm has not been accurately investigated. This study phenotypically assessed 75 selected cultivars released to farmers in Denmark, Finland, Norway and Sweden within the last 10 decades. Grouping of cultivars was not related to their geographical origin or decade of release. The respective within-cluster variances were always larger than the among-cluster variances. The average phenotypic diversity for Nordic spring wheat germplasm was 0.22, which was not surprising because some newer cultivars were derived from older cultivars. There was a significant influence of geographical origin on days to heading, straw, grain and biomass weight, and kernel number. Likewise, the country x decade of release interaction was significant for all characteristics except plant height. These findings suggest that irrespective of location, Nordic breeders have reduced plant height in recently released cultivars at a rate of - 0.5 cm year(-1), thereby reducing lodging in this germplasm. There was no significant change in biomass, straw and kernel weight between old and new cultivars. Nonetheless, relative genetic gains in this germplasm during this century were significant for agronomic characteristics, such as days to heading (8%), plant height (36%), grain yield (20%), harvest index (19%), and number of kernels per unit area (18%). On average, the absolute genetic gain for grain yield was about 18.5 kg ha(-1) year(-1). Negative changes in days to heading (at a rate of - 0.06 year(-1)) and plant height, and positive changes in harvest index (0.06% year(-1)), and kernels m(-2) (45 year(-1)) were associated with gains observed in grain yield, i.e. an early flowering plant with short straw, but many fertile tillers, had high grain yield. This sustained genetic gain could result from the accumulation of favourable alleles and intergenomic interactions between homologous loci during systematic plant breeding for grain yield.

Proper classification and establishment of relationships between and within Musa taxonomic clusters will be important tools for the genetic improvement of plantain and banana. This paper assesses the value of a phenotypic diversity index, based on 16 quantitative descriptors, for germplasm clustering and for identification of duplicates among 92 triploid plantain and banana accessions. Data were recorded during the plant and ratoon crops at Onne, a humid forest location in southeastern Nigeria. The phenotypic distance matrix was developed by calculating the average difference between each pair of accessions for all quantitative descriptors. Significant differences were observed for this phenotypic distance index between Musa taxonomic clusters. The between-cluster variance was larger (0.001779) than the within-cluster variance (0.001380). Wright’s φFS, which measures the overall diversity, was 0.5663. This value suggested little gene flow among triploid taxonomic clusters via pollen, which explains the higher population differentiation exhibited by this vegetatively propagated crop with very low male fertility. The results also suggested that variation observed within each Musa taxonomic cluster arose from mutations accumulated throughout the history of cultivation of this crop. Some putative duplicates based on qualitative descriptors were not regarded as the same accession according to the phenotypic diversity index based on quantitative descriptors. Hence, gene-bank curators should assess quantitative descriptors for the identification of duplicate accessions in Musa.

Both Lolium perenne and L. multiflorum are strong outbreeders that exhibit severe inbreeding depression (Bean & Yok-Hwa, 1972; Matzk, 1974) and possess a strict gametophytic self-incompatibility system which involves two major gene loci with modification by the genetic background (Lawrence et al., 1983).

Suspension culture performance in commercial varieties of perennial ryegrass was studied to assess the effect of variety on suspension culture response and plant regeneration. 179 suspension cultures were established from embryos of mature seeds of 21 varieties and one breeding population. Of these, 123 suspensions were morphogenic (21 varieties) and 66 suspensions (18 varieties) regenerated green plants. A number of suspension lines, originating from two different suspensions, retained the capacity for green plant formation for almost four years. Replicates performed with seed lots of different ages indicated that suspensions initiated from young seeds (1 year) were of better quality than suspensions initiated from older seeds (2–4 years). Varieties differed in their capacity to form morphogenic suspensions and suspensions capable of regenerating green plants, although the effect of variety was relatively small. It was concluded that responsive genotypes can be found within most varieties of Lolium perenne.

Genotypic effects on callus induction and plant regeneration in callus, suspension and protoplast culture, and their correlations with both phenotypic and GCA-values for anther culture response, were studied using 21 genotypes of perennial ryegrass. Differences between genotypes accounted for approximately 40% of the total variation for callus induction and initial callus growth, and 59 and 83% of the variation in callus culture for regeneration percentage and percentage of green plants. Effects of genotypes were less pronounced in suspension culture, where suspensions from the same genotype often behaved differently. Some suspension cultures retained their capacity for green plant regeneration for almost two years, repeatedly producing 80–100% green regenerants during this period. Genotypes with high regeneration percentage and a large proportion of green plants from callus culture were also superior in suspension culture for both regeneration performance and longevity. Regeneration percentage and percentage of green plants were uncorrelated, and probably under different genetic control. While capacity for green plant formation from the different genotypes showed no correlation between anther culture and somatic in vitro culture, a positive correlation was observed between the regeneration percentages in somatic in vitro culture and anther culture (r=0.44*−0.85***), suggesting some common genetic control of the two systems.

Genetic control of the capacity to respond to anther culture in perennial ryegrass was studied in F-1 offspring from crosses between 11 clones selected for anther-culture response ('inducers') and 10 clones selected from breeding material on the basis of good agronomic performance. Large differences in anther-culture response were observed between the two types of parent, with inducer clones producing an average of 10.7 green plants per 100 anthers, compared with only 0.3 for breeding clones. Hybrid populations produced an average of 2.2 green plants per 100 plated anthers, which is 7.3 times the response of the breeding material. This improvement was mainly due to a 9.4-fold increase in the percentage of green plants regenerated from hybrid populations to 4.7% compared to an average of 0.5% from breeding clones. Most of the GCA (general combining ability) in the experiment was contributed by the breeding material, constituting 55.8, 100.0 and 36.7% of genetic variation among hybrids for embryo formation, regeneration and green plant percentage, respectively. Any remaining genetic variation among hybrids was predominantly due to SCA (specific combining ability) effects, with percentages of 44.2 and 63.3%, respectively, for embryo and green plant formation. These results are discussed with respect to the possible exploitation of genes controlling anther-culture response for haploid production in breeding programmes of perennial ryegrass.

An efficient nurse culture system was established for perennial ryegrass protoplast culture which allowed up to 59 000 protoplast-derived green plants to be regenerated from 1 ml of sedimented suspension cells. Nurse cultures improved plating efficiency, vitality of the protoplast-derived colonies and the frequency of green plants (number of green plants/100 plants), while regeneration frequency (number of plants/100 colonies) was determined mainly by the protoplast donor suspension. Conditioned medium taken from the embryogenic protoplast-donor suspension (self-conditioning) increased the plating efficiency and frequency of green plants, while conditioned media harvested from 6 other suspensions on average had a negative effect on colony formation and colony vitality. Concentrated self-conditioned medium resulted in a higher plating efficiency than self-conditioned medium diluted 1:1 with protoplast culture medium. Nurse culture was more efficient than conditioned medium at normal protoplast density and was also superior for compensating suboptimal protoplast density. There is evidence that the conditioning effect was reduced to 50% when the conditioned medium was stored for 2 days, suggesting involvement of unstable chemical factors and that the superiority of nurse cultures may be due to a continuous supply of conditioning compounds.

The self-fertility of chromosome-doubled haploid lines of perennial ryegrass and their first (I1) and second (I2) generation selfed offspring was studied. The overall seed set was low, 0-0.4 seeds per spike, as would be expected for chromosome-doubled haploids of a self-incompatible species. Nevertheless, significant genetic variation was observed for self-fertility within three of the six lines studied. Within one line, three 12-clones showed increased self-fertility, while in two other lines one and three I1-clones, respectively, showed significantly increased self-fertility. Selection, during selfing, of rare pollen grains with mutations in the self-incompatibility system could explain the observed changes and would lead to a general breakdown of self-incompatibility in Lolium perenne during repeated selfing of chromosome-doubled haploids.

Acta Medica ScandinavicaVolume 169, Issue 4 p. 381-387 Long-term Treatment of Cirrhosis of the Liver with Prednisone Bent Harvald, Bent Harvald Medical Department C, Bispebjerg Hospital and Department III, Kommunehospitalet, Copenhagen, DenmarkSearch for more papers by this authorSten Madsen, Sten Madsen Medical Department C, Bispebjerg Hospital and Department III, Kommunehospitalet, Copenhagen, DenmarkSearch for more papers by this author Bent Harvald, Bent Harvald Medical Department C, Bispebjerg Hospital and Department III, Kommunehospitalet, Copenhagen, DenmarkSearch for more papers by this authorSten Madsen, Sten Madsen Medical Department C, Bispebjerg Hospital and Department III, Kommunehospitalet, Copenhagen, DenmarkSearch for more papers by this author First published: January/December 1961 https://doi.org/10.1111/j.0954-6820.1961.tb07846.xCitations: 20AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onEmailFacebookTwitterLinkedInRedditWechat References 1 Brugel, H. & Mertz, D. P.: Cit. K. Beckmann: Die Leberkrankheiten. Georg Thieme Verlag, Stuttgart 1957, p. 182. Google Scholar 2 Cattan, R. & Vesin, P.: Sem. Hôp. Paris 33: 76, 1957. CASPubMedGoogle Scholar 3 Cattan, R. & Vesin, P.: Therapie 12: 601, 1957. CASPubMedGoogle Scholar 4 Evans, A. S., Sprinz, H. & Nelson, R. S.: Ann. Int. Med. 38: 1115, 1953. 10.7326/0003-4819-38-6-1115 CASPubMedWeb of Science®Google Scholar 5 Fraisse, Pean & Brondel: J. Méd. Lyon 38: 255, 1957. CASPubMedGoogle Scholar 6 Gajdusek, D. C.: Arch. Int. Med. 101: 9, 1958. 10.1001/archinte.1958.00260130023003 CASPubMedWeb of Science®Google Scholar 7 Goldgraber, M. B. & Kirsner, J. B.: Arch. Int. Med. 104: 469, 1959. 10.1001/archinte.1959.00270090123018 Web of Science®Google Scholar 8 Hanger, F. M. & Collins, G. L.: Trans. Ass. Amer. Physns. 63: 272, 1950. CASPubMedWeb of Science®Google Scholar 9 Katz, R., Ducci, H. & Alessandri, H.: J. Clin. Invest. 36: 1370, 1957. 10.1172/JCI103536 CASPubMedWeb of Science®Google Scholar 10 Winkler, K. & Tygstrup, N.: Acta med. scand. 157: 149, 1957. 10.1111/j.0954-6820.1957.tb14419.x CASPubMedWeb of Science®Google Scholar Citing Literature Volume169, Issue4January/December 1961Pages 381-387 ReferencesRelatedInformation