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Genetic variance within the genotype of population and its mapping to phenotype variance in a systematic and high throughput manner is of interest for biodiversity and breeding research. Beside the established and efficient high throughput genotype technologies, phenotype capabilities got increased focus in the last decade. This results in an increasing amount of phenotype data from well scaling, automated sensor platform. Thus, data stewardship is a central component to make experimental data from multiple domains interoperable and re-usable. To ensure a standard and comprehensive sharing of scientific and experimental data among domain experts, FAIR data principles are utilized for machine read-ability and scale-ability. In this context, BrAPI consortium, provides a comprehensive and commonly agreed FAIRed guidelines to offer a BrAPI layered scientific data in a RESTful manner. This paper presents the concepts, best practices and implementations to meet these challenges. As one of the worlds leading plant research institutes it is of vital interest for the IPK-Gatersleben to transform legacy data infrastructures into a bio-digital resource center for plant genetics resources (PGR). This paper also demonstrates the benefits of integrated database back-ends, established data stewardship processes, and FAIR data exposition in a machine-readable, highly scalable programmatic interfaces. [ABSTRACT FROM AUTHOR]

Copyright of Tropical Grasslands / Forrajes Tropicales is the property of International Centre for Tropical Agriculture - CIAT and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Prosopis affinis is native tree of the Brazilian Pampa, recognized as an important species to local culture and economy. Despite the ecological and the economic potential of this tree, studies in Brazil are limited to descriptions of the occurrence sites of P. affinis. Aiming to determine the existence of diversification at floral and/or at population levels for this species, morphological characteristics of inflorescences and flowers of Prosopis affinis growing in the Pampa biome were measured, while the pollen/ovule ratio and the outcrossing index were determined as an indirect estimate of the species breeding system. No clear reproductive specialization related to flower position in the inflorescence was observed, although basal flowers in the inflorescence presented reduction of the androecium. The results also showed that P. affinis presents a breeding system intermediary between facultative autogamy and xenogamy, with upper stamens supporting self-pollination, reduced stamens supporting outcrossing and the likely occurrence of an evolutionary shift at geographical level. These findings highlight the importance of conserving the remnants of P. affinis in southern Brazil and further investigate the pollination biology, the breeding system and the genetic diversity of this species, promoting its conservation and better understanding the effect of forest fragmentation in the Pampa biome. Further analyzes comparing isolated and larger continuous populations, as well as estimations of the real outcrossing rate of P. affinis through genetic studies and controlled experiments to evaluate auto-compatibility are recommended in order to generate more information about this issue. [ABSTRACT FROM AUTHOR]

An experiment was conducted to study the spectrum of genetic variation for seed yield per plant and its component traits in the four selection procedures [PS(EF), PS(HY), SSD and RBP] each with 20 progenies in GJG 0315 x ICCV 96029 in F5 generation in Desi chickpea (Cicer arietinum L.). Analysis of variance revealed significant genotypic differences for all the characters with wide range of variation. Out of the total 6 cases studied in F5, PS(EF) in 2 cases; SSD in 3 cases sand PS(HY) in 1 case were better for depicting the widest phenotypic range and maximum coefficient of range, irrespective of characters. Moderate to high heritability and genotypic co-efficient of variation coupled with high expected genetic advance as per cent of mean was observed for number of branches per plant by PS(HY) and RBP and for 100-seed weight in PS(EF), PS(HY) and SSD of this cross which indicated the predominant role of additive gene action in the expression of these traits in respective breeding schemes. [ABSTRACT FROM AUTHOR]

Seventy groundnut genotypes were evaluated for quantitative and yield parameters. A wide range of variation was observed for important yield components. High estimates of the genotypic coefficient of variation (GCV) were observed for kernel yield per plant followed by the number of branches per plant, harvest index and biological yield per plant. The estimates of heritability were observed to be high for harvest index followed by biological yield per plant, kernel yield per plant, 100-kernel weight, plant height, 100-pod weight and number of branches per plant indicated that these characters were less influenced by the environmental fluctuations. High heritability along with high genetic advance was observed for 100-pod weight. High heritability along with moderate genetic advance was observed for biological yield per plant, 100- kernel weight and harvest index indicating that these traits were mainly governed by additive gene action and responsive for further improvement of these traits. [ABSTRACT FROM AUTHOR]

The study was undertaken to estimate genetic characterization, character association direct and indirect effects by path analysis for pod yield per plant and its components by using 15 groundnut genotypes. Dry pod yield per plant shown to have maximum genotypic coefficient of variation followed by kernel per plant suggesting substantial amount of genetic variability. Dry pod yield per plant, kernel yield per plant, 100- kernel weight, days to maturity was observed high heritability and high genetic advance these traits were controlled by additive genes and can easily be transferred to succeeding generations. Dry pods per plant registered positive and significant genotypic and phenotypic correlations with kernel yield per plant and 100- kernel weight. It indicated that the selection for increased dry pods per plant may give higher kernel yield per plant and 100- kernel weight and thus, may contribute in increasing the dry pods per plant. The path coefficient analysis revealed that the kernel yield per plant, oil content and shelling percentage exhibited high and positive direct effect on dry pod yield per plant. Thus, these characters turned out to be the major components of pod yield and direct selection for these traits may be rewarding for yield improvement. [ABSTRACT FROM AUTHOR]

An attempt was made to determine the degree of divergence in 64 genotypes of chilli which were evaluated in a Randomized Complete Block Design with three replications during summer-rainy season 2015. The observations were recorded on 17 biometrical traits including 14 quantitative and three qualitative traits. A considerable amount of genetic diversity was observed among the genotypes, arranged in eight clusters with maximum in cluster II and four were monogenotypic cluster. Leaf length contributed maximum towards total genetic divergence followed by fruit length, primary branches/plant, plant height, capsaicin content, fresh fruit yield/plant, pedicel length, oleoresin content and fruit girth. Based on intra and inter cluster distance and mean performance for desirable attributes, Nine genotypes namely, DPCh-17, DPCh- 39', 'DPCh-12, DPCh-9, DPCh-35, DPCh-45, DPCh-5, DPCh-28 and DPCh-43 from diverse clusters along with 'DPCh- 10, DPCh-36, DPCh-8 and DPCh-15 from mono-genotypic groups offer promise for their direct use as varieties and as potential parents in future breeding programmes to isolate transgressive segregants. [ABSTRACT FROM AUTHOR]

High temperature is a major constraint to crop adaptation and productivity in groundnut especially when coincides with moisture stress. In the present study, thirty nine groundnut germplasm comprising of interspecific derivatives, advanced breeding lines, mutants and released cultivars were evaluated for their thermo tolerance at seedling stage in the laboratory under induced temperature treatment. Highly significant differences were observed among temperature treatments, genotypes and genotype x temperature interactions indicating differential response of genotypes to temperature treatment. High heritability coupled with high genetic advance over mean under induced temperature treatment revealed better scope for selection in the germplasm under induced temperature. Foliar disease resistant mutant (Mutant 110) and several advanced breeding lines (R 9214, ICGV 96266, ICGV 96262, ICGV 93020, ICGV 91177, ICGV 87264 and NC Ac 343) and three released cultivars (K 134, TMV 2 and Dh 40) have shown very less reduction (<30%) under induced temperature treatment indicating their seedling thermo-tolerance. These genotypes need to be assessed for their temperature tolerance under field conditions at different stages of crop growth. [ABSTRACT FROM AUTHOR]

Twenty F1s were developed by utilizing nine diverse parents 4 lines and 5 testers in Line x Testers mating design During Kharif 2015. The estimates of mean sum of squares due to male, female, male vs female, hybrids and parents vs hybrids showed significant variation. Large numbers of heterotic crosses were observed in most of the characters. The maximum positive standard heterosis for dry pod yield plant-1 (g) over best check TKG-Bold was observed in RHRG 6083 x TAG 24 (63.31%) followed by RHRG 6083 x JL 777(54.14%) and RHRG 1225 x TAG 24 (42.07%) and significant heterosis for other yield contributing traits viz., number of primary branches plant-1, number of pods plant-1, number of kernels pod-1, dry haulm yield plant-1, 100 kernel weight and shelling percentage. The maximum negative standard heterosis for days to maturity over best check TKG-Bold was observed in TG 37A x ICG 2630 (-18.61%) followed by RHRG 1225 x TAG 24 (- 12.50) and TG 37A x JL 777(-11.67). The combinations viz., RHRG 6083 x TAG 24, RHRG 6083 x JL 777 and RHRG 1225 x TAG 24 could be utilize for selection of desirable segregants in further segregating generations. [ABSTRACT FROM AUTHOR]

Combining ability analysis performed using 15 parental lines and their 54 hybrids in pearl millet in L x T mating design. The magnitude of SCA variances was higher than the GCA variances for all the characters, which indicated predominance of non-additive gene action in the inheritance of these traits and it was further supported by less magnitude of σ²gca / σ²sca ratios. Based on general combining ability (gca) effects, none of the parent was good general combiners for all the characters. Among females, JMSA-9904 was good general combiner for grain yield per plant and protein content. Whereas, male parent J-2507 was good general combiner for grain yield per plant, Fe content and Zn content. The heterotic hybrid ICMA-96333 x J-2512 had recorded high sca effects for grain yield per plant and exhibited positive significant sca for Zn content. The hybrid ICMA-96333 x J-2510 was recorded high and favourable sca effect for Fe content (50.12) and Zn content (44.07). In case of protein content, hybrid JMSA-9904 x J-2538 was exhibited high positive sca effect, this cross also recorded positive sca effect for Fe content, Zn content and grain yield. [ABSTRACT FROM AUTHOR]

Combining ability analysis for grain yield and its contributing traits in maize was performed with 15 inbred line and 3 tester parents and the resulting 45 hybrids using line x tester cross analysis in three environments during kharif and rabi 2014. The results of combining ability analysis over the environments revealed significant mean squares due to general and specific combining ability indicating that both additive and non-additive gene actions were important in the inheritance of characters studied. The parents L2 (EIQ -132), L4(EIQ-134), L5(EIQ-135), L6(EIQ-136), L8(EIQ-138), and L14(EIQ-144) and L15 (EIQ- 145) were good general combiners for grain yield and majority of traits over the environments. Hence, these parents can be used in crossing and further exploited for improvement of traits in the population. Six inbred lines viz., L1(EIQ-131), L2(EIQ - 132), L3(EIQ-133), L6(EIQ-136), L8(EIQ-138) and L14(EIQ-144) were identified good general combiner for maturity related traits. Whereas the crosses L7 x T2 (EIQ-137 x EIQ-102), L13 x T3 (EIQ-143 x EIQ-103), L10 x T1 (EIQ-140 x EIQ-101), L1 x T1(EIQ-131 x EIQ-101) and L11 x T3 (EIQ-141 x EIQ-103) were identified as potential ones for yield and yield components based on high sca effects along with high per se performance. These hybrids may be exploited for commercial cultivation by testing them over locations and years for their yield stability. [ABSTRACT FROM AUTHOR]

Fourteen parents and 40 F1 crosses (genetic male sterility based) were evaluated in a line x tester fashion in Asiatic cotton (Gossypium arboreum). The statistical analysis was performed using the method developed by Kempthorne (1957) with the help of OPSTAT computer program (developed by CCS Haryana Agricultural University, Hisar. Sufficient variability among hybrids and their parents was found as the mean squares of genotypes for all the traits including fibre quality were significant. The variance due to GCA was lower than SCA for boll number per plant, boll weight and GOT. For other traits like seed cotton yield, fibre length, micronaire value and strength, the SCA was higher which reflected the role of both additive and non-additive types of gene action (dominant or epistatic). GCA was significant for male parents CISA-6-165, CISA-6-187, CISA-6-209, CISA-6-295, CISA-6-350, CISA 7, CISA 8 and female parents CISA 2, DS 5, GAK 413A for seed cotton yield. Parents CISA-6-123, CISA-6-165, CISA-6-350, CISA 8, CISA 9, GAK 413A, CISG 20 showed significant GCA for fibre length and CISA-6-123, CISA-6-350, CISA 8 for micronaire value. Among 40 cross combinations, SCA was positively significant for seed cotton yield in 5 crosses, for boll number in 16 crosses, for boll weight in 9 crosses and for fibre length and micronaire in 16 crosses. [ABSTRACT FROM AUTHOR]

The Genes Software is useful for analyzing and processing phenotypic and molecular data using different biometric models. In the current version we dispose routines to integrate it with three other softwares: the R, Matlab and Selegen. This version allows in plant and animal breeding complementary analyzes in several breeding research fields as genomic selection, prediction of genetic values, use of neural networks and Fuzzy logic. The Genes is important to estimate parameters for understanding biological phenomena necessary to make decisions and predict the success and viability of strategic selection. The original programme can be downloaded in Portuguese, English or Spanish with the specific literature from (http://www.livraria.ufv.br/) and the user guide from (http://www.ufv.br/dbg/genes/genes.htm and http://www.ufv.br/dbg/biodata.htm). The user has also support in the address www.facebook.com/ GenesNews. The Genes is also integrated in the application softwares MS Word, MS Excel and Paint to efficiently import data and export results as numbers and figures. [ABSTRACT FROM AUTHOR]

The phenotypic characterization of sour cherry cultivars provides important information on their attributes, which is of paramount importance for their breeding and germplasm management. This study examined the Hellenic Sour Cherry Genebank, which consists of 27 sour cherry cultivars, located in the Institute of Pomology Fruit Genebank, Naoussa, Greece. The data analyzed in this study were obtained after a ten-year consecutive monitoring of 38 morpho-physiological descriptors of phenology, plant morphology, yield and fruit quality. For the statistical analysis were applied hierarchical cluster analysis and principal component analysis (PCA). According to the analysis, the descriptors demonstrated a high degree of variability, especially, yield, ratio of titratable acidity and soluble solids, number of flower buds, and pit weight. Moreover, the variables fruit equatorial diameter, fruit width, fruit weight, fruit size, fruit shape and lamella shape characters exhibited high discriminating power. Significant positive and negative correlations were detected as well among the studied quantitative traits. The highest significant positive correlation was found between the fruit equatorial diameter and the fruit width (0.974). Whereas, the highest significant negative correlation was found between the ratio of pit volume to fruit volume and the fruit weight (−0.737). An unsupervised hierarchical cluster analysis was performed using the Euclidean distance and the Ward's agglomeration method. The sour cherry cultivars were classified into three main clusters, suggesting that the characterized sour cherry collection has a high potential for specific breeding goals. We discuss the usefulness of the identified correlations among the traits, for potential breeding projects regarding fruit size and quality. [ABSTRACT FROM AUTHOR]

The wild species in the Triticeae tribe are tremendous resources for crop breeding due to their abundant natural variation. However, their huge and highly repetitive genomes have hindered the establishment of physical maps and the completeness of their genome sequences. To develop molecular markers for the efficient utilization of their valuable traits while avoiding their genome complexity, we assembled RNA sequences of ten representative accessions of Aegilops tauschii, the progenitor of the wheat D genome, and estimated single nucleotide polymorphisms (SNPs) and insertions/deletions (indels). The deduced unigenes were anchored to the chromosomes of Ae. tauschii and barley. The SNPs and indels in the anchored unigenes, covering entire chromosomes, were sufficient for linkage map construction, even in combinations between the genetically closest accessions. Interestingly, the resolution of SNP and indel distribution on barley chromosomes was slightly higher than on Ae. tauschii chromosomes. Since barley chromosomes are regarded as virtual chromosomes of Triticeae species, our strategy allows capture of genetic markers arranged on the chromosomes in order based on the conserved synteny. The resolution of these genetic markers will be comparable to that of the Ae. tauschii whose draft genome sequence is available. Our procedure should be applicable to marker development for Triticeae species, which have no draft sequences available. [ABSTRACT FROM AUTHOR]

Breeding for disease resistance is a central focus of plant breeding programs, as any successful variety must have the complete package of high yield, disease resistance, agronomic performance, and end-use quality. With the need to accelerate the development of improved varieties, genomics-assisted breeding is becoming an important tool in breeding programs. With marker-assisted selection, there has been success in breeding for disease resistance; however, much of this work and research has focused on identifying, mapping, and selecting for major resistance genes that tend to be highly effective but vulnerable to breakdown with rapid changes in pathogen races. In contrast, breeding for minor-gene quantitative resistance tends to produce more durable varieties but is a more challenging breeding objective. As the genetic architecture of resistance shifts from single major R genes to a diffused architecture of many minor genes, the best approach for molecular breeding will shift from marker-assisted selection to genomic selection. Genomics-assisted breeding for quantitative resistance will therefore necessitate whole-genome prediction models and selection methodology as implemented for classical complex traits such as yield. Here, we examine multiple case studies testing whole-genome prediction models and genomic selection for disease resistance. In general, whole-genome models for disease resistance can produce prediction accuracy suitable for application in breeding. These models also largely outperform multiple linear regression as would be applied in marker-assisted selection. With the implementation of genomic selection for yield and other agronomic traits, whole-genome marker profiles will be available for the entire set of breeding lines, enabling genomic selection for disease at no additional direct cost. In this context, the scope of implementing genomics selection for disease resistance, and specifically for quantitative resistance and quarantined pathogens, becomes a tractable and powerful approach in breeding programs. [ABSTRACT FROM AUTHOR]

Orchids are one of the most commercialized potted flowers in the world. Cattleya hybrids are highly valued by the international flower market but its horticultural characteristics can still benefit from genetic improvement, particularly the production of precocious cultivars and season-independent flowering. This improvement would allow Cattleya to compete with Phalaenopsis and Dendrobium orchids, as well as with other potted and cut-flower groups. The aim of this work was first to obtain interspecific hybrids between two superior cultivars, Cattleya 'Pão de Açucar' and Brassolaeliocattley 'Sun King'. This was followed by selection among the progeny for precocious flowering and other valuable horticultural and ornamental characteristics. Seedlings grown in vitro were initially selected based on shoot and root development over a period of 6 months, then acclimatized in a greenhouse. From a total of 200 acclimatized plantlets, five (i.e., 2.5 %) flowered 2 years after acclimatization. This was approximately half the time required to flower for most of the remaining progeny. This novel progeny showed gains in most morphological characteristics evaluated relative to their parents. One of the hybrids obtained ('BR501') flowered four times a year and had ornamentally and horticulturally important characteristics related to pot-flower production, including novel color, compact plant size, a greater number and larger inflorescences and flowers. This hybrid can be included in further breeding programs of the Cattleya hybrid group. [ABSTRACT FROM AUTHOR]

Soluble sugar and organic acid levels are important evaluation indices for breeding new varieties of pear. In order to investigate the inheritance of sugars and acids, this study analyzed the inheritance of soluble sugar and organic acid in pear fruit using the reciprocal crossing populations 'Dangshansuli' and 'Housui' over two successive years. The results showed that the content of most individual acids and sugars, total acid and total sugar content were higher than that of 'Dangshansuli' and lower than that of 'Housui', trending to an average between the parents. The content of oxalate, quinate, malate, shikimate, and total acid in progenies were higher when 'Housui' was the maternal parent, suggesting that the selection of the maternal parent during the breeding process has important effects on the acid content. Conversely, individual and total sugar content did not show significant effects of the maternal parent. In addition, glucose content in progenies showed the increasing trend and sorbitol content showing the transgressive inheritance trait. The correlations for total sugar and total acid of the two populations between 2 years were significant and positive, showing stable sugar and acid traits for fruit in different years. Significant and positive correlations were also found between different components, including oxalate and malate, shikimate and quinate, and citrate and shikimate. Principal component analysis also revealed that oxalate, quinate, malate and shikimate components are closely correlated. Our study thus offers useful information for future pear breeding to improve sugar and acidity quality. [ABSTRACT FROM AUTHOR]

The genus Passiflora L. has about 80 species with edible fruits and desirable agronomic characteristics which can be transferred to commercial species for further breeding by artificial hybridization. The aim of this study is to determine the self-fertility (SF) and interspecific compatibility of six commercially cultivated species and six wild species as a resource for future breeding programs. Reciprocal interspecific pollinations were carried out involving twelve species for a total of 144 hybrids combinations. The test of SF showed that seven species display no more than 5 % of fruit set, indicating self-incompatibility ( P. cincinnata, P. maliformis, P. caerulea, P. mucronata and P. vitifolia, P.alata and P. edulis f. flavicarpa). Percentage of formed fruits in a fruit set ranged from 2.1 to 60 % and results showed significant differences in the effectiveness of some species in crosses when acting as the female parent. The highest fruit set was obtained when the female parent was P. vitifolia, P. mucronata and P. edulis f. edulis and P. edulis f. flavicarpa ranging from 22.2 to 60 %. Regarding fruit production, 48.1 % of the successful crosses reached physiological maturity giving a total of 21 fruits with similar sizes and number of seeds, as compared to the ones obtained by natural pollination. Post-zygotic barriers were detected in 53.8 % of the crosses where a fruit was formed due to failure in seed endosperm development or low germination. The highest percentage of germination was obtained in crosses of P. mucronata × P. alata and P. edulis f . flavicarpa × P. vitifolia with 87.5 and 100 %, respectively. The finding of high compatibility of some hybrid combinations in this study is promising. However, the performance of F hybrids needs to be determined in field evaluations to assess the real potential for further breeding. [ABSTRACT FROM AUTHOR]

Much of the cost associated with marker discovery for marker assisted breeding (MAB) can be eliminated if a diverse, segregating population is generated, genotyped, and made available to the global breeding community. Herein, we present an example of a hybrid, wild-derived family of the octoploid strawberry that can be used by other breeding programs to economically find and tag useful genes for MAB. A pseudo test cross population between two wild species of Fragaria virginiana and F. chiloensis (FVC 11) was generated and evaluated for a set of phenotypic traits. A total of 106 individuals in the FVC 11 were genotyped for 29,251 single nucleotide polymorphisms (SNPs) utilizing a commercially available, genome-wide scanning platform (Affymetrix Axiom IStraw90TW). The marker trait associations were deduced using TASSEL software. The FVC 11 population segregating for daughters per mother, inflorescence number, inflorescence height, crown production, flower number, fruit size, yield, internal color, soluble solids, fruit firmness, and plant vigor. Coefficients of variations ranged from 10% for fruit firmness to 68% for daughters per mother, indicating an underlying quantitative inheritance for each trait. A total of 2,474 SNPs were found to be polymorphic in FVC 11 and strong marker trait associations were observed for vigor, daughters per mother, yield and fruit weight. These data indicate that FVC 11 can be used as a reference population for quantitative trait loci detection and subsequent MAB across different breeding programs and geographical locations. [ABSTRACT FROM AUTHOR]

Genomic selection in crop breeding introduces modeling challenges not found in animal studies. These include the need to accommodate replicate plants for each line, consider spatial variation in field trials, address line by environment interactions, and capture nonadditive effects. Here, we propose a flexible single-stage genomic selection approach that resolves these issues. Our linear mixed model incorporates spatial variation through environment-specific terms, and also randomization-based design terms. It considers marker, and marker by environment interactions using ridge regression best linear unbiased prediction to extend genomic selection to multiple environments. Since the approach uses the raw data from line replicates, the line genetic variation is partitioned into marker and nonmarker residual genetic variation (i.e., additive and nonadditive effects). This results in a more precise estimate of marker genetic effects. Using barley height data from trials, in 2 different years, of up to 477 cultivars, we demonstrate that our new genomic selection model improves predictions compared to current models. Analyzing single trials revealed improvements in predictive ability of up to 5.7%. For the multiple environment trial (MET) model, combining both year trials improved predictive ability up to 11.4% compared to a single environment analysis. Benefits were significant even when fewer markers were used. Compared to a single-year standard model run with 3490 markers, our partitioned MET model achieved the same predictive ability using between 500 and 1000 markers depending on the trial. Our approach can be used to increase accuracy and confidence in the selection of the best lines for breeding and/or, to reduce costs by using fewer markers. [ABSTRACT FROM AUTHOR]

Genomic prediction relies on genotypic marker information to predict the agronomic performance of future hybrid breeds based on trial records. Because the effect of markers may vary substantially under the influence of different environmental conditions, marker-by-environment interaction effects have to be taken into account. However, this may lead to a dramatic increase in the computational resources needed for analyzing large-scale trial data. A high-performance computing solution, called Needles, is presented for handling such data sets. Needles is tailored to the particular properties of the underlying algebraic framework by exploiting a sparse matrix formalism where suited and by utilizing distributed computing techniques to enable the use of a dedicated computing cluster. It is demonstrated that large-scale analyses can be performed within reasonable time frames with this framework. Moreover, by analyzing simulated trial data, it is shown that the effects of markers with a high environmental interaction can be predicted more accurately when more records per environment are available in the training data. The availability of such data and their analysis with Needles also may lead to the discovery of highly contributing QTL in specific environmental conditions. Such a framework thus opens the path for plant breeders to select crops based on these QTL, resulting in hybrid lines with optimized agronomic performance in specific environmental conditions. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Plant Science is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background: Identification of transgene insertion sites in plant genomes has practical implications for crop breeding and is a stepping stone to analyze transgene function. However, single copy sequences are not always easy to localize in large plant genomes by standard approaches. Results: We employed flow cytometric chromosome sorting to determine chromosomal location of barley sucrose transporter construct in three transgenic lines of common wheat. Flow-sorted chromosomes were used as template for PCR and fluorescence in situ hybridization to identify chromosomes with transgenes. The chromosomes carrying the transgenes were then confirmed by PCR using DNA amplified from single flow-sorted chromosomes as template. Conclusions: Insertion sites of the transgene were unambiguously localized to chromosomes 4A, 7A and 5D in three wheat transgenic lines. The procedure presented in this study is applicable for localization of any single-copy sequence not only in wheat, but in any plant species where suspension of intact mitotic chromosomes suitable for flow cytometric sorting can be prepared. [ABSTRACT FROM AUTHOR]

Background: Microspore embryogenesis describes a stress-induced reprogramming of immature male plant gametophytes to develop into embryo-like structures, which can be regenerated into doubled haploid plants after whole genome reduplication. This mechanism is of high interest for both research as well as plant breeding. The objective of this study was to characterize transcriptional changes and regulatory relationships in early stages of cold stress-induced wheat microspore embryogenesis by transcriptome and small RNA sequencing using a highly responsive cultivar. Results: Transcriptome and small RNA sequencing was performed in a staged time-course to analyze wheat microspore embryogenesis induction. The analyzed stages were freshly harvested, untreated uninucleate microspores and the two following stages from in vitro anther culture: directly after induction by cold-stress treatment and microspores undergoing the first nuclear divisions. A de novo transcriptome assembly resulted in 29,388 contigs distributing to 20,224 putative transcripts of which 9,305 are not covered by public wheat cDNAs. Differentially expressed transcripts and small RNAs were identified for the stage transitions highlighting various processes as well as specific genes to be involved in microspore embryogenesis induction. Conclusion: This study establishes a comprehensive functional genomics resource for wheat microspore embryogenesis induction and initial understanding of molecular mechanisms involved. A large set of putative transcripts presumably specific for microspore embryogenesis induction as well as contributing processes and specific genes were identified. The results allow for a first insight in regulatory roles of small RNAs in the reprogramming of microspores towards an embryogenic cell fate. [ABSTRACT FROM AUTHOR]

The development of resistant cultivars is an alternative to control phytosanitary problems affecting passion fruit crops. This study was conducted to obtain progenies through interspecific crosses between Passiflora edulis × Passiflora mucronata, perform the genetic assessment of the progenies obtained, and evaluate and select genotypes resistant to Fusarium solani. When P. mucronata was used as female parent, 516 seeds were obtained, with 20 % germination and survival of nine hybrid genotypes. On the other hand, in the reciprocal cross, 9 seeds were obtained and only one genotype survived. Due to the small number of genotypes obtained, 10 hybrid genotypes and their parents P. edulis (susceptible) and P. mucronata (resistant) was propagated by cuttings. Nine plantlets of each genotype were taken to the field in a randomized block design, with three replications, aiming at morphological characterization. Twenty quantitative and 7 qualitative descriptors were assessed. Nine clones of each individual were kept in a greenhouse, inoculated with F. solani, and assessed 76 days after inoculation. Later, the fungus was re-isolated. The offspring genotypes of the cross in which P. edulis was the female parent did not flourish. For most quantitative and qualitative traits, hybrids were similar to P. mucronata. The genotypes studied formed six groups. Resistance to the fungus was detected in the genotypes of P. mucronata, from Bahia, and two hybrid genotypes. The resistant hybrid can be backcrossed with P. edulis and/or used as rootstock for sour passion fruit. [ABSTRACT FROM AUTHOR]

Cultivation of spinach requires high amounts of nitrogen (N), which puts a strain on the environment. A sustainable solution to this problem is to breed for crops with higher N use efficiency (NUE). The aim of this study was to provide tools for molecular breeding and to elucidate the genetic variation of factors contributing to NUE in spinach. A cross was made between two F hybrid cultivars contrasting in NUE. Several F1 progeny were self-pollinated and based on evaluation of the F2 generation, a mapping F population (335 individuals) of a single F1 was selected. SNP markers for the genetic map were discovered by RNA sequencing of the two parent cultivars, and 283 SNP markers were used to produce a genetic map comprising of six linkage groups (P01-P06), ranging in size from 46 to 116 cM. NUE related traits were determined for a set of F families grown under low and high N conditions in a hydroponics system under an Ingestad N-addition model. Interval mapping analysis detected 39 trait-specific QTLs, with several QTLs accumulating on P01 and P02 of the linkage map. The QTLs and in particular the P01 and P02 regions provide potential targets for the improvement of NUE in spinach. [ABSTRACT FROM AUTHOR]

We studied the drought response of eight commercial hybrid maize lines with contrasting drought sensitivity together with the reference inbred line B73 using a non-invasive platform for root and shoot phenotyping and a kinematics approach to quantify cell level responses in the leaf. Drought treatments strongly reduced leaf growth parameters including projected leaf area, elongation rate, final length and width of the fourth and fifth leaf. Physiological measurements including water use efficiency, chlorophyll fluorescence and photosynthesis were also significantly affected. By performing a kinematic analysis, we show that leaf growth reduction in response to drought is mainly due to a decrease in cell division rate, whereas a marked reduction in cell expansion rate is compensated by increased duration of cell expansion. Detailed analysis of root growth in rhizotrons under drought conditions revealed a strong reduction in total root length as well as rooting depth and width. This was reflected by corresponding decreases in fresh and dry weight of the root system. We show that phenotypic differences between lines differing in geographic origin (African vs. European) and in drought tolerance under field conditions can already be identified at the seedling stage by measurements of total root length and shoot dry weight of the plants. Moreover, we propose a list of candidate traits that could potentially serve as traits for future screening strategies. [ABSTRACT FROM AUTHOR]

Sesame is an important oil crop widely cultivated in Africa and Asia. Understanding the genetic diversity of accessions from these continents is critical to designing breeding methods and for additional collection of sesame germplasm. To determine the genetic diversity in relation to geographical regions, 96 sesame accessions collected from 22 countries distributed over six geographic regions in Africa and Asia were genotyped using 33 polymorphic SSR markers. Large genetic variability was found within the germplasm collection. The total number of alleles was 137, averaging 4.15 alleles per locus. The accessions from Asia displayed more diversity than those from Africa. Accessions from Southern Asia (SAs), Eastern Asia (EAs), and Western Africa (WAf) were highly diversified, while those from Western Asia (WAs), Northern Africa (NAf), and Southeastern Africa (SAf) had the lowest diversity. The analysis of molecular variance revealed that more than 44% of the genetic variance was due to diversity among geographic regions. Five subpopulations, including three in Asia and two in Africa, were cross-identified through phylogenetic, PCA, and STRUCTURE analyses. Most accessions clustered in the same population based on their geographical origins. Our results provide technical guidance for efficient management of sesame genetic resources in breeding programs and further collection of sesame germplasm from these different regions. [ABSTRACT FROM AUTHOR]

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The rapid growth and co-option of the local agriculture movement highlights a need to deepen connections to place-based culture. Selection of plant varieties specifically adapted to regional production and end-use is an important component of building a resilient food system. Doing so will facilitate a defetishization of food systems by increasing the cultural connection to production and consumption. Today's dominant model of plant breeding relies on selection for centralized production and end-use, thereby limiting opportunity for regional differentiation. On the other hand, end-user-driven selection of heirloom varieties with strong cultural and culinary significance may limit productivity while failing to promote continued advances in end-use quality. Farmer-based selection may directly reflect local food culture; however, increasing genetic gains may require increased exchange of germplasm, and collaboration with trained plant breeders. Participatory farmer–breeder–chef collaborations are an emerging model for overcoming these limitations and adding the strength of culturally based plant breeding to the alternative food movement. These models of variety selection are examined within the context of small grain and dry bean production in Western Washington. [ABSTRACT FROM PUBLISHER]

Background: Vascular wilt caused by Fusarium oxysporum is the most important disease in cape gooseberry (Physalis peruviana L.) in Colombia. The development of resistant cultivars is considered one of the most cost-effective means to reduce the impact of this disease. In order to do so, it is necessary to provide breeders with molecular markers and promising germplasm for introgression of different resistance loci as part of breeding schemes. Here we described an association mapping study in cape gooseberry with the goal to: (i) select promising materials for use in plant breeding and (ii) identify SNPs associated with the cape gooseberry resistance response to the F. oxysporum pathogen under greenhouse conditions, as potential markers for cape gooseberry breeding. Results: We found a total of 21 accessions with different resistance responses within a diversity panel of 100 cape gooseberry accessions. A total of 60,663 SNPs were also identified within the same panel by means of GBS (Genotyping By Sequencing). Model-based population structure and neighbor-joining analyses showed three populations comprising the cape gooseberry panel. After correction for population structure and kinship, we identified SNPs markers associated with the resistance response against F. oxysporum. The identification of markers was based on common tags using the reference genomes of tomato and potato as well as the root/stem transcriptome of cape gooseberry. By comparing their location with the tomato genome, 16 SNPs were found in genes involved in defense/resistance response to pathogens, likewise when compared with the genome of potato, 12 markers were related. Conclusions: The work presented herein provides the first association mapping study in cape gooseberry showing both the identification of promising accessions with resistance response phenotypes and the identification of a set of SNP markers mapped to defense/resistance response genes of reference genomes. Thus, the work also provides new knowledge on candidate genes involved in the P. peruviana -- F. oxysporum pathosystem as a foundation for further validation in marker-assisted selection. The results have important implications for conservation and breeding strategies in cape gooseberry. [ABSTRACT FROM AUTHOR]

Durable resistance, conditioned by minor resistance genes, has been described as more reliable in managing angular leaf spot (ALS) disease in the long term. The aim of this study was to develop a breeding method for durable ALS resistance in common bean and use it to accumulate minor genes into single genotypes. Four genotypes with intermediate resistance to ALS were selected from an initial 182 genotypes and used to generate a double cross segregating population. The F was planted in a nethouse and inoculated with a mixture of races of the ALS pathogen. The genotypes that showed intermediate resistance to ALS were subsequently selected from the F to the F segregating populations. In the F generation resistant plants were selected and the F plants were evaluated, together with the parents and several market class varieties. Data were collected on ALS disease severity, seed yield, days to physiological maturity, seed size, seed colour and growth habit. Ten F advanced lines with enhanced levels of resistance (disease score 1.9-3.2) were selected. These lines had improved resistance when compared to their parents (disease score 4.6-4.8) and market class varieties (disease score 5.4-8.2), which confirmed breeding progress for resistance to ALS. Simultaneous selection was done for seed yield, seed size, farmer preferred seed type and growth habit. The results of the study have shown that it is possible to develop ALS resistant common bean lines through the double cross method, using a mixture of ALS races. [ABSTRACT FROM AUTHOR]

To benefit from expansion in space, a clonal plant must at first invest some of its resources in the production of clonal offspring. When resources are scarce, investment in clonal growth can be costly. Investment could be more costly in the case of long compared to short rhizomes. However, benefits can also be substantial if the plant can attain resources from a large area. Thus, both the growth form and soil fertility can influence the balance between costs and benefits from clonal growth. We established an experiment in which half of the plants of Elymus repens (long rhizomes) and Alopecurus pratensis (short rhizomes) were planted through a black agrotextile sheet laid on either a fertile or an infertile soil. The textile sheet prevented clonal offspring from reaching sunlight. The other half of the plants were allowed to grow freely. The size of the genets and the number of clonal offspring (daughter ramets) were primarily affected by soil fertility while covering only impacted the growth of E. repens. Covering increased the seed production of A. pratensis by almost 50 % while total rhizome length per genet of E. repens was significantly larger in the nutrient-poor soil and in covered conditions. E. repens benefited from clonal growth only in fertile conditions where genets grew bigger, whereas A. pratensis showed no signs of direct benefit. We conclude that it is essential to consider the growth form of genets when evaluating the relationships between clonal growth or reproductive behaviour and environmental conditions. [ABSTRACT FROM AUTHOR]

Background: Mungbean (Vigna radiata [L.] R. Wilczek) is an important legume crop with high nutritional value in South and Southeast Asia. The crop plant is susceptible to a storage pest caused by bruchids (Callosobruchus spp.). Some wild and cultivated mungbean accessions show resistance to bruchids. Genomic and transcriptomic comparison of bruchid-resistant and -susceptible mungbean could reveal bruchid-resistant genes (Br) for this pest and give insights into the bruchid resistance of mungbean. Results: Flow cytometry showed that the genome size varied by 61 Mb (mega base pairs) among the tested mungbean accessions. Next generation sequencing followed by de novo assembly of the genome of the bruchid-resistant recombinant inbred line 59 (RIL59) revealed more than 42,000 genes. Transcriptomic comparison of bruchid-resistant and -susceptible parental lines and their offspring identified 91 differentially expressed genes (DEGs) classified into 17 major and 74 minor bruchid-resistance-associated genes. We found 408 nucleotide variations (NVs) between bruchid-resistant and -susceptible lines in regions spanning 2 kb (kilo base pairs) of the promoters of 68 DEGs. Furthermore, 282 NVs were identified on exons of 148 sequence-changed-protein genes (SCPs). DEGs and SCPs comprised genes involved in resistant-related, transposable elements (TEs) and conserved metabolic pathways. A large number of these genes were mapped to a region on chromosome 5. Molecular markers designed for variants of putative bruchid-resistance-associated genes were highly diagnostic for the bruchid-resistant genotype. Conclusions: In addition to identifying bruchid-resistance-associated genes, we found that conserved metabolism and TEs may be modifier factors for bruchid resistance of mungbean. The genome sequence of a bruchid-resistant inbred line, candidate genes and sequence variations in promoter regions and exons putatively conditioning resistance as well as markers detecting these variants could be used for development of bruchid-resistant mungbean varieties. [ABSTRACT FROM AUTHOR]

Background: Heterosis or hybrid vigour is a phenomenon in which hybrid progeny exhibit superior performance compared to their parental inbred lines. Most commercial Chinese cabbage cultivars are F1 hybrids and their level of hybrid vigour is of critical importance and is a key selection criterion in the breeding system. Results: We have characterized the heterotic phenotype of one F1 hybrid cultivar of Chinese cabbage and its parental lines from early- to late-developmental stages of the plants. Hybrid cotyledons are larger than those of the parents at 4 days after sowing and biomass in the hybrid, determined by the fresh weight of leaves, is greater than that of the larger parent line by approximately 20 % at 14 days after sowing. The final yield of the hybrid harvested at 63 days after sowing is 25 % greater than the yield of the better parent. The larger leaves of the hybrid are a consequence of increased cell size and number of the photosynthetic palisade mesophyll cells and other leaf cells. The accumulation of plant hormones in the F1 was within the range of the parental levels at both 2 and 10 days after sowing. Two days after sowing, the expression levels of chloroplast-targeted genes in the cotyledon cells were upregulated in the F1 hybrid relative to their mid parent values. Shutdown of chlorophyll biosynthesis in the cotyledon by norflurazon prevented the increased leaf area in the F1 hybrid. Conclusions: In the cotyledons of F1 hybrids, chloroplast-targeted genes were upregulated at 2 days after sowing. The increased activity levels of this group of genes suggested that their differential transcription levels could be important for establishing early heterosis but the increased transcription levels were transient. Inhibition of the photosynthetic process in the cotyledon reduced heterosis in later seedling stages. These observations suggest early developmental events in the germinating seedling of the hybrid may be important for later developmental vigour and yield advantage. [ABSTRACT FROM AUTHOR]

Background: High potential of Morus laevigata and Morus serrata has been proposed in the breeding programs for Morus sp. However, due to the lack of dense molecular markers this goal is still in its nascent stage and not yet realized. We thus, sequenced the transcriptomes of these two wild Morus species and utilized the data for marker development. Results: We generated 87.0 and 80.3 Mb of transcriptome data from M. laevigata and M. serrata, respectively. The transcriptomes from M. laevigata and M. serrata, were assembled into 95,181 and 85,269 transcripts, respectively, and annotated. We identified around 24,049 Simple Sequence Repeats (SSRs), 1,201,326 Single Nucleotide Polymorphisms (SNPs) and 67,875 Insertion-Deletions (InDels). The variants having a higher impact were also identified and their effect was further investigated. Conclusions: The transcriptome resource from the wildly growing mulberry species developed in this study can find wide applicability in gene identification and/or characterization. It can also contribute immensely in the existing mulberry improvement programs. [ABSTRACT FROM AUTHOR]

Process-based grassland models (PBMs) simulate growth and development of vegetation over time. The models tend to have a large number of parameters that represent properties of the plants. To simulate different cultivars of the same species, different parameter values are required. Parameter differences may be interpreted as genetic variation for plant traits. Despite this natural connection between PBMs and plant genetics, there are only few examples of successful use of PBMs in plant breeding. Here we present a new procedure by which PBMs can help design ideotypes, i.e. virtual cultivars that optimally combine properties of existing cultivars. Ideotypes constitute selection targets for breeding. The procedure consists of four steps: (1) Bayesian calibration of model parameters using data from cultivar trials, (2) Estimating genetic variation for parameters from the combination of cultivar-specific calibrated parameter distributions, (3) Identifying parameter combinations that meet breeding objectives, (4) Translating model results to practice, i.e. interpreting parameters in terms of practical selection criteria. We show an application of the procedure to timothy ( Phleum pratense L.) as grown in different regions of Norway. [ABSTRACT FROM AUTHOR]

The need for new improved cultivars adapted to modern cultivation techniques and changing climatic environment requires genetic studies able to provide a better understanding of the phenotypic variance decomposition into genetic and environmental variances. In perennial crops, this decomposition requires evaluations carried out among years, trees within a genotype, samples within a tree and their interactions. The aim of this study was to perform such a detailed variance analysis of oil content components (fruit fresh weight-FFW, fruit moisture-FM, oil content on both fresh-OCFFW and dry-OCFDW basis) and fruit morphology traits (fruit maximum diameter-FMD and fruit circularity-FC) in an olive progeny issued from the cross 'Oliviere' × 'Arbequina'. A total of 106 genotypes from this progeny, together with the parents cultivars, were evaluated over two consecutive years in two trees/genotype, and three samples/tree for oil content components and 30 samples/tree for fruit morphology traits. Two dataset were considered during analysis. The first one, including a limited number of genotypes without any missing data, was fully balanced and ANOVA was applied for variance components estimation from expected mean squares. The second dataset contained the full unbalanced information of the 106 genotypes and mixed linear models were built following to the same statistical model. Both analyses showed that variance among genotypes (σ) was the main contributor to total variance for FFW, OCFFW and OCFDW and variance among years (σ) for FM. Residual error effect (σ) was the main contributor for morphology traits, whereas variance associated with the genotype × year interaction (σ) and tree × year interaction (σ) represented also important variance components for most traits, and variance among trees within a genotype (σ) was negligible. Consistently, the mean broad sense heritabilities (H²) showed the lowest values for FM (0.40) and the highest values for OCFFW (0.94). An estimation of heritability and environmental variation under varying numbers of years and tree replications revealed that including more yearly replications could be more effective than adding trees replications. Finally, this study provides a global view of adequate spatial and temporal replications required to accurately develop criteria for both conventional and marker-assisted selection on fruit traits from olive crossing progenies, and more generally in fruit trees. [ABSTRACT FROM AUTHOR]

Sugar beet is hypothesized to have a narrowed genetic base due to its origin as White Silesian Beet and from numerous breeding selections and practices. High sugar quality, yield of recoverable sugar, cytoplasmic-male sterility system, monogermity, pests and disease resistance and bolting resistance constitute some of the adaptations that significantly influenced the existing genetic background of the crop. In this study we aimed to evaluate the extent of genetic diversity existing in wild beet representatives of Beta and Patellifolia and sugar beet cultivars, with a special focus on the complex Beta vulgaris. Another purpose was to determine the potential usefulness and conformity of selected molecular markers in different groups of materials in the context of rhizomania resistance. To reach these goals, molecular RAPD, ISSR techniques, literature-selected rhizomania resistance-segregating sequences as well as mitochondrial markers were used. The comparison of genetic diversity in wild and cultivated Beta forms shows that the population differentiation values and distance values are relatively high in cultivars. Moreover, the diversity component seemed to be compromised rather on the level of population (Hs) than in total (Ht) in cultivars. Our results shed a new light on the expected genetic bottlenecks existing in cultivars and revealed features specific for individual taxa ( Patellifolia, Corollinae). Some degree of distinctiveness was suggested between genetic determinants of rhizomania resistance in modern cultivars in comparison with wild resistance sources. In addition, we document here an internal heterogeneity existing in selected wild/weedy accessions at the level of crucial sequences using high resolution melting. [ABSTRACT FROM AUTHOR]

Background:Taxonomic analysis provides a basic understanding for taxon identification and contributes to preliminary information for several branches of applied biology, while studies on reproductive strategies and plant fitness are essential to interpret population status and dynamics. Aims:We tested the reliability of diagnostic characters for identification and to characterise sexual resource allocation, the breeding system and seed predation among subspecies ofGentiana lutea. Methods:We analysed morphological characters in 70 herbarium specimens. In five natural populations we counted pollen and ovule numbers, assessed reproductive output after pollination treatments and evaluated pre-dispersal predation. Results:Taxonomic traits previously indicated as diagnostic were not sufficient to discriminate among subspecies. The pollen number and pollen:ovule (P:O) ratio varied strongly among subspecies; self-pollinated flowers produced a significantly lower number of seeds than open-pollinated flowers. Retention of empty fruits and high levels of pre-dispersal seed predation were observed in every case. Conclusions:The variation of P:O ratios among subspecies suggests different efficiency in pollen transfer. The species is self-compatible, nevertheless all subspecies require pollen vectors to enhance cross pollination and viable seed production. Fruit retention may have evolved as a strategy to reduce predation, ensuring higher plant fitness. [ABSTRACT FROM PUBLISHER]

The eating and cooking qualities of rice are heavily emphasized in breeding programs because they determine market values and they are the appealing attributes sought by consumers. Conventional breeding has developed traditional varieties with improved eating and cooking qualities. Recently, intensive genetic studies have pinpointed the genes that control eating and cooking quality traits. Advances in genetic studies have developed molecular techniques, thereby allowing marker-assisted breeding (MAB) for improved eating and cooking qualities in rice. MAB has gained the attention of rice breeders for the advantages it can offer that conventional breeding cannot. There have been successful cases of using MAB to improve the eating and cooking qualities in rice over the years. Nevertheless, MAB should be applied cautiously given the intensive effort needed for genotyping. Perspectives from conventional breeding to marker-assisted breeding will be discussed in this review for the advancement of the eating and cooking qualities of fragrance, amylose content (AC), gel consistency (GC) and gelatinization temperature (GT) in rice. These four parameters are associated with eating and cooking qualities in rice. The genetic basis of these four parameters is also included in this review. MAB is another approach to rice variety improvement and development in addition to being an alternative to genetic engineering. The MAB approach shortens the varietal development time, and is therefore able to deliver improved rice varieties to farmers within a shorter period of time. [ABSTRACT FROM PUBLISHER]

Coriander is the most important seed spice crop in India. Selection is the most common breeding procedure used in coriander and crossing is non-existent. The present study was conducted to promote crossing as a breeding technique in coriander. It was found that coriander was protandrous and the sex ratio was 1.75 to 2.07. The stigma was receptive from the 3rd day to 6th day of anthesis indicating that artificial pollination on emasculated florets must be done repeatedly on 3rd and 4th day of anthesis. Pollen was viable for two days in the field. Fresh pollen can be stored in incubator at 25oC for three weeks with 88% retention of viability. Emasculation of florets was carried out with the help of binocular loupe. Emasculation either in the morning before anthesis or previous day evening was found to be suitable. For demonstrating the technique, four parents were reciprocally crossed. Only three crosses were successful indicating the differences in combining ability of the parents. Mean success among the crosses was 23%, fruit set among the florets varied from 9.52-83.3% depending on the cross combination. [ABSTRACT FROM AUTHOR]

This study was carried out to develop and produce cucumber inbred lines possessing high level of resistance to the root-knot nematodes, Meloidogyne spp. combined with highly commercially acceptable characters. The study was performed under micro-plot and field conditions extending for three successive years (2012-2015) as a complementary phase to a previous breeding program to satisfy the goal of this study. Evaluation for resistance was estimated based on four nematode parameters, viz., root gall index, number of galls, number of egg masses and number of eggs (fecundity). The study included five host cycles in two phases. The first phase included two generations grown in two successive cycles under micro-plot conditions with artificial nematode infestation. The second phase included three generations in three field growing cycles (natural infestation) in Gezerit El-Dahab location, Giza, Egypt. Results showed that level of resistance was gradually increased with the progress in the inbreeding program by selecting the most resistant plants to nematode infection, which were 77.93, 81.35, 97.37, 97.56 and 98% for F2, F3, F4, F5 and F6, respectively. The last advanced step in the breeding program yielded three inbred lines, highly resistant to Meloidogyne spp. compared with local variety Beit Alpha. The best inbred line was characterized by outstanding values of flowering characters as number of days to first female flower (33.83 days) compared with (49.93 days) for Beit Alpha. As to yield character, it was 4.83 kg/plant compared with 2.38 kg/plant for Beit alpha. These inbred lines are potentially promising as a good source for producing new hybrids characterized by high nematode resistance level and good yield quantity and quality. [ABSTRACT FROM AUTHOR]

Responses of the wheat commercial cultivar 'Faisalabad-2008' to various concentrations of 2,4-D and the effect of water stress on callus induction and regeneration efficiency were evaluated. For the assessment of responses to water stress, growing morphogenic calli of 7, 14 and 21 days after culture were exposed to different concentrations of water stress. For induction of stress wheat calli were exposed to different concentrations of PEG 6000 (0, 4, 8, 12 and 16% (w/v) and mannitol (0, 0.5, 1, 1.5 and 2% (w/v). The effect of these stresses on shoot and root length, relative water content and electrolyte leakage were also determined. The results indicated that maximum regeneration was observed at 5mg/L of 2,4-D, increase or decrease in 2,4-D concentration resulted a decrease in regeneration efficiency. Maximum regeneration was observed from 21 days old calli. Significant decreases in the number of shoots regenerated per calli; shoot and root length and relative water contents occurred under both stresses with the highest reduction under mannitol-induced osmotic stress. Electrolyte leakage increased at higher PEG and mannitol concentrations. Furthermore, both PEG and mannitol induced drought stress efficiently but mannitol was more severe. The results here will be helpful for improvement of the wheat crop tolerance against water stress. [ABSTRACT FROM AUTHOR]

Louisiana iris is tolerant to and accumulates the heavy metal lead (Pb). However, there is limited knowledge of the molecular mechanisms behind this feature. We describe the transcriptome of Louisiana iris using Illumina sequencing technology. The root transcriptome of Louisiana iris under control and Pb-stress conditions was sequenced. Overall, 525,498 transcripts representing 313,958 unigenes were assembled using the clean raw reads. Among them, 43,015 unigenes were annotated and their functions classified using the euKaryotic Orthologous Groups (KOG) database. They were divided into 25 molecular families. In the Gene Ontology (GO) database, 50,174 unigenes were categorized into three GO trees (molecular function, cellular component and biological process). After analysis of differentially expressed genes, some Pb-stress-related genes were selected, including biosynthesis genes of chelating compounds, metal transporters, transcription factors and antioxidant-related genes. This study not only lays a foundation for further studies on differential genes under Pb stress, but also facilitates the molecular breeding of Louisiana iris. [ABSTRACT FROM AUTHOR]

Availability of standardized morphological and molecular characterization data is essential for the efficient development of breeding programmes in emerging crops. Pepino ( Solanum muricatum) is an increasingly important vegetatively propagated vegetable crop for which concurrent data on morphological descriptors and molecular markers are not available. We evaluated 58 morphological traits, using a collection of 14 accessions of pepinos (including local Andean varieties and modern cultivars) and 8 of wild relatives, using the IPGRI and COMAV descriptors lists coupled with 20 EST-SSRs from tomato. High morphological diversity was found in both cultivated and wild accessions; all morphological traits except three were variable. Cultivated pepino and wild relatives were significantly different for 26 traits. Also, local varieties and modern cultivars of pepino were different from each other for 13 morphological traits and were clearly separated in a principal components analysis. Fourteen of the 20 tomato EST-SSRs were polymorphic, with an average number of alleles per locus of 4.07 and a polymorphic information content value of 0.4132. This revealed a high degree of transferability from tomato to pepino and wide molecular diversity in the collection. Cultivated materials manifest high levels of observed heterozygosity, suggesting that it is related to heterosis for yield associated with heterozygosis. SSR data clearly differentiated cultivated and wild materials. Furthermore, for pepinos, the modern varieties were genetically much less diverse than the traditional local varieties. However, both groups of cultivated material expressed a low degree of genetic differentiation. A strong correlation (r = 0.673) between morphological and molecular distances was found. Our results provide foundational information for programmes of germplasm conservation, and that can be used to enhance breeding for this emerging crop. [ABSTRACT FROM AUTHOR]

High frequency of albino haploids/doubled haploids (DHs), regenerated in androgenic cultures is one of the major obstacles that limit incorporation of DHs technology into cereal breeding programs. Therefore, quantitative trait loci (QTL) associated with albino plant production in triticale anther cultures were analyzed using the population of 90 DH lines derived from F1 cross 'Saka 3006' × 'Modus'. Composite interval mapping (CIM) and single marker analysis (SMA) in Windows QTL Cartographer ver 2.5 were used to localize the major QTLs. CIM method revealed seven QTLs with LOD scores between 2.9 and 5.6 on five chromosomes from B to R subgenomes (3B, 4B, 4R, 5R and 7R). Effects of all QTLs explained 8.3-17.6 % of the phenotypic variation and were confirmed by SMA analysis. Additionally SMA revealed another seven markers on chromosomes: 2AL.2BL, 3B, 2BS.6AL, 2RS.3R and 4R associated with QTL for albino plant regeneration (p < 0.01). The additional experiment with ten DH lines varied significantly in their androgenic responsiveness was conducted to analyze the changes in the level of oxidative stress, antioxidative system activity and endogenous hormonal balance associated with androgenesis-inducing low temperature stress treatment (3 weeks at 4 °C). The correlation analysis between albino/green plant regeneration ability and analyzed traits were performed by using Spearman Rank test (p ≤ 0.05). Revealed associations may suggest that some level of oxidative stress is necessary for transition from a non-photosynthetic proplastids to the functional chloroplasts. On the other hand, the efficient antioxidative enzyme system and endogenous hormonal balance are also very important. Key message: Fourteen chromosome regions were indicated to control albino plant formation during triticale anther culture. Additionally, reactive oxygen species (ROS) generation, antioxidative system activity and hormonal balance were discussed as determinants in androgenesis. [ABSTRACT FROM AUTHOR]