Comparison of anther and isolated microspore cultures in barley. Effects of culture density and regeneration medium

Genetic variation in ratoon growth and cane yieldafter mechanical harvesting under wet conditions wasexamined among 26 sugarcane clones of diverse geneticbackground, including materials closely related toSaccharum spontaneum and some commercialcultivars. The clones were evaluated under a controltreatment (harvesting under dry conditions andallowing the cane to ratoon without furtherdisturbance), and a traffic treatment (sprayirrigation and then driving heavy field equipment overthe cane stubble immediately after harvesting). Averaged over all clones, the traffic treatment had alarge adverse effect on early growth and final ratoonyield. There was significant genotype × treatmentinteraction for early growth and canopy development,but not for final cane yield. There was also a highgenetic correlation between genetic performance underthe different treatments, indicating that selectionfor ratooning after dry harvesting conditions would bealso effective for improving performance after wetharvesting conditions. A sugarcane breeding programspecifically targeting better ratoon performance underwet conditions would be difficult to justify.     

A quick methodology to identify sexual seedlings in citrus breeding programs using SSR markers

In citrus breeding and genetics, it is very important to distinguish between zygotic and nucellar seedlings in order to eliminate unwanted genotypes. Usually, isozyme marker shave been employed to determine the genetic origin of young plants. In this work we propose the use of SSR markers as an alternative methodology and compare them with isozymes in this kind of screenings. Two different populations were analysed: one derives from an interspecific cross and the other from selfing. We conclude that, in most cases, microsatellites are more efficient than isozymic markers to identify the sexual origin of citrus seedlings, given their higher level of polymorphism and the scarce number of polymorphic isozymes in some populations. We describe a quick and efficient methodology for SSR analysis, including a fast DNA extraction in microcentrifuge tubes, and visualization through silver staining, which eliminates the need for a labelling step. This revised version was published online in July 2006 with corrections to the Cover Date.     

Breeding for breadmaking quality using old Hungarian wheat varieties

Due to their broad population diversity, old wheat varieties or landraces play an important role in increasing the genetic variability of agronomic traits. On these grounds, an analysis was made of the high molecular weight (HMW) glutenin subunit composition of the old Hungarian wheat variety Bánkúti 1201. It was found that several genotypes with differing breadmaking qualities can be distinguished for this character. When using old varieties in breeding, it is possible to broaden the genetic background of characters responsible for breadmaking quality by separating the populations. A more detailed analysis of the protein composition of germplasm created in this way will be required to obtain a better understanding of this complex character for its conscious introduction into breeding programmes. This revised version was published online in August 2006 with corrections to the Cover Date.     

Sclerotinia resistance in sunflower: I. Genotypic variations of hybrids in three environments of Argentina

Sclerotinia sclerotiorum infections on sunflower capitula produce white rot, one of the most dangerous diseases sunflower bears in all humid areas. Therefore, disease quantification on developed genetic materials is a very important action in sunflower breeding. Given the horizontal type of resistance these evaluations should be made in different environments. Several hybrids obtained after crossing seven female × seven male sunflower inbred lines in a factorial mating design were evaluated for resistance to white rot in two locations in the southeast of the province of Buenos Aires, Argentina. Disease incidence and the symptom appearance index indicated significant genotypic effects and genotype × environment (G × E) interactions. Genotypic effects were a greater source of variance than the G × E interaction effects. The G × E interactions only represented changes in magnitude. These results were used to identify the best genotypes for both resistance factors. Four hybrids showed low disease incidence values under both artificial and natural infections, of which only two had high values of the symptom appearance index at both locations. These hybrids are considered to have adequate resistance attributes for the ascosporic penetration and the mycelium extension in the capitulum tissue and could therefore be sown in the province of Buenos Aires without increasing risks of S. sclerotiorum attacks.     

Innovation strategies for smart specialisation (RIS3): Past,present and future research

The recent change in the regional development strategy of the European Union (EU) results in an important need to study the terms of change and their respective implications. This study seeks, through a bibliometric analysis, to ascertain the developments taking place in studies on research and innovation strategies for smart specialisation (RIS3) to identify shortcomings and opportunities for future research. This bibliometric review drew upon the Scopus database with the sample selected containing all the articles containing the keywords “Research and Innovation Strategies for Smart Specialisation” or “RIS3.” This correspondingly reports how some authors maintain that the path the EU should take involves imitative innovation. Meanwhile, others propose that each region should specialise in those industries that are already established there and thus avoid targeting any areas they do not already know/specialise in. Our findings detail six clusters in RIS3 research, which help in contextualising the literature review: (a) business discovery; (b) smart specialisation; (c) innovation; (d) specialisation; (e) regional policies; and (f) regional development. This study furthermore sets out perspectives for future lines of research and correspondingly seeks to convey a vast theoretical basis that may serve as the point of departure for future studies.     

Biplot analysis of trait relations of white lupin in Spain

A 2-year study of autumn-sown white lupin (Lupinus albus L.) was conducted under rainfed Mediterranean conditions in southern Spain. 108 landraces were evaluated for yield and major phonological and plant structural characteristics. Path coefficient and Genotype-Trait (GT) biplot analysis were used. Applying both types of analyses to the multiple trait data revealed that GT biplot graphically displayed the interrelationships among traits and facilitated visual comparison of accessions and selection. Wide variation was observed for trait phenology (dates of flowering and maturity), plant structure (plant and first order inflorescence height) and yield characters (first order branches, first order inflorescence and total yield). It was found that the accessions with the highest yields were the tallest and the latest to flower, both on the mainstem and on the lowest first order branch, and also were the latest to mature. GT biplots also had suggested as the accessions have been displayed according to their origins. The results showed that foreign germplasm may be an important material for improving some yield components such as number of pods and seeds per plant of locally adapted lupins in Spain. This revised version was published online in July 2006 with corrections to the Cover Date.     

Improved <Emphasis Type="Italic">S</Emphasis>-genotyping and new incompatibility groups in Japanese plum

The selection of cross-compatible cultivars is essential to ensure fruit set in self-incompatible species like Japanese plum and thus the S-genotype must be determined in order to establish incompatibility groups. In this study an improved Japanese plum S-genotyping method, based in polymerase chain reaction and capillary electrophoresis detection of intron polymorphisms of S-locus genes, S-RNase and SFB, has been assayed and validated in a wide sample of cultivars. This method allows a more precise determination of amplified fragment sizes and therefore a better differentiation of self-incompatibility alleles. The assayed methodology was proven effective in the detection of 13 different S-alleles of S-RNases and SFBs and was used to S-genotype 105 Japanese plum cultivars, 32 of which are described by first time in this work. Analysed cultivars were assigned into 11 incompatibility groups and two new incompatibility groups (XX and XXI) were identified, increasing to 21 the number of incompatibility groups described in this crop.     

Phenotypic segregation and relationships of agronomic traits in Monastrell × Syrah wine grape progeny

The aim of this work was to study the phenotypic segregation of different agronomic and fruit quality traits, and their relationships, in Monastrell × Syrah wine grape progeny. Twenty-two agronomic traits were evaluated and compared for three consecutive years in this progeny. The results show the phenotypic diversity existing in a cross between two different wine grape cultivars. Most of the phenological, productive, morphological, and enological parameters evaluated displayed continuous variation within the progeny, suggesting a polygenic inheritance. Some correlations between traits were detected by the Spearman correlation test, although high coefficients were not found for most of them. Cluster analysis of the progeny grouped the hybrids based on criteria with significance for wine grape breeding. Also, we investigated the relationship between the skin color and total content of anthocyanins with the VvmybA genotype, using the CAPS (Cleaved Amplified Polymorphic Sequence) marker 20D18CB9. The results show that hybrids with two copies of the functional color allele tend to have increased anthocyanins content. Based on this study, 14 genotypes were pre-selected from the breeding population for additional quality studies.     

Towards an objective evaluation of persistency of <Emphasis Type="Italic">Lolium perenne</Emphasis> swards using UAV imagery

Perennial ryegrass (Lolium perenne) is a perennial crop used in temperate regions as forage. In L. perenne breeding programs, persistency is an important trait. Poor persistency results in sward degradation and associated yield and nutritive value losses. Breeders assess persistency of accessions using visual scoring in field plots during the 2nd or 3rd growing season. This evaluation system is easy and cheap but is not free from human bias. In this study, the correlation between the scoring done by different breeders was only 0.243. As an alternative we have developed a methodology to assess persistency of L. perenne breeding materials based on vegetation indices (VIs) derived from Unmanned Aerial Vehicle (UAV) imagery. The VIs Excess green (ExG2), Green Leaf Index and Normalized green intensity (GCC) were found to provide consistent results for flights carried out under different light conditions and were validated by ground reference information. The correlation between the VIs and the percentage of ground cover extracted from on-ground imagery was 0.885. To test the implementation of the method we compared the ExG2 value based approach to selection with a visual score based selection methodology as applied by two breeders. The breeding decisions of Breeder A agreed well with decisions based on ExG2 values (74.6%), but those of Breeder B displayed a lower agreement (54.0%). In contrast, agreement between decisions based on different flights was very high (91.6%). The methodology was validated for general applicability. In summary, the results demonstrate that basing persistency selection in L. perenne breeding programs on ExG2 values from UAV imagery is likely to be more objective in comparison to the currently-used visual scoring method.