Distinct Cultivars Research Articles

Genome-wide association study on ten traits of economic importance in hop (Humulus lupulus L.)

Hop is used primarily for bittering and flavoring of beer although new uses of hop have been implemented in poultry production, sugar processing and pharmaceuticals. Traditional hop breeding is a lengthy, expensive process. Modern selection methods such as marker-assisted selection are needed to greatly improve genetic gains per selection cycle as well as reduce the number of experimental lines evaluated in the field. Recent implementation of next generation sequencing enables the scanning of whole genomes for markers linked to traits of interest using an analysis called genome-wide association studies (GWAS). This study was initiated to identify markers associated with expression of 10 different traits in hop. Illumina Inc. technology sequencing of 116 genetically distinct hop cultivars from multiple regions of the world was performed. SNP marker identification was achieved using the TASSEL v3.0 UNEAK pipeline. Filtering of SNP markers resulted in a working group of 32,206 SNP markers screened across all 116 cultivars. Phenotypic data for all cultivars were collected over a 35-year period and data from four years were used. Mixed linear models analyses in TASSEL v5.0.0 were used for five of the traits while the remaining five traits were evaluated using general linear models. A total of 86 SNP markers were identified and reported as significantly associated with one of the 10 traits. Heritability for traits matched with those previously published. This is the first reported genome wide association study in hop and as such represents an important step forward in aiding marker assisted selection. Nevertheless, it remains that further validation of these SNP markers is needed prior to implementation in a breeding program.

Discrimination of Camellia japonica cultivars and chemometric models: An interlaboratory study

Camellia japonica is a valued plant since ancient times throughout the world mostly due to their ornamental flowers. It has a high number of cultivars, with very similar phenotypic and genotypic characteristics which are difficult to discriminate, being some of them often rare and with a high price at the market. Their discrimination is mostly done through visual inspection of the morphologic characteristics which is a hard and inefficient task. Spectroscopic techniques had already been used for taxonomic purposes at species and sub-species level with success and could be an alternative for accurate C. japonica cultivars discrimination. Despite the already recognized success of such techniques, most of the studies arises from a single laboratory and little is known about the robustness of these techniques regarding interlaboratory data transferability. In this context, the work developed herein presents a double aim: (I) to explore the ability of near infrared (NIR) spectroscopy and partial least square – discriminant analysis (PLS-DA) to discriminate C. japonica cultivars and (II) to evaluate data transferability between two independent laboratories (Lab A and Lab B). Air-dried leaves NIR spectra of 43 C. japonica plants (15 distinct cultivars) were acquired in both laboratories using two similar NIR instruments (same manufacturer and model). Spectra were further modelled by PLS-DA after exploratory analysis using principal component analysis (PCA): (I) individually for Lab A and Lab B; (II) using Lab A as calibration and Lab B as validation set and vice-versa and (III) with using Lab A and Lab B data together. The percentage of C. japonica cultivars discrimination for both laboratories was nearly the same (around 83%) indicating no significant differences between Lab A and Lab B analysis. However, the results were quite poor when spectra were modelled with data from a single laboratory and validated with the other (65.5 and 63.8%). When data were merged, 85.9% of correct cultivars assignments were obtained. The results herein obtained could benefit of including additional cultivars and plants; but demonstrated the ability of NIR spectroscopy for C. japonica cultivars discrimination. Regarding data transferability, even when dealing with a similar instrument, some issues arisen preventing easy and efficient spectral library transfers.

Optimisation of regeneration parameters improves transformation efficiency of recalcitrant tomato

Genetic transformation of tomato was first accomplished around 30 years ago. However, variability in transformation efficiency of distinct cultivars exists and to some extent remains a bottleneck for transgenic research. This study reports strategies to improve transformation efficiency in tomato and investigates regeneration capacity of transgenic plants under different selection regimes and hormonal applications. Tomato cv. Rio Grande was used as plant material and hygromycin and phosphinothricin (PPT) were used as selection agents. We found that cv. Rio Grande inherently produced a significant number of abnormal (“blind”) shoots lacking an apical meristem. Replacing cytokinin zeatin riboside with 6-benzylaminopurine (BAP) reduced the number of blind shoots although it slightly prolonged regeneration time. Survival rate of calli and shoots was very low using PPT as selection, whereas regeneration was achieved using hygromycin. Delayed application of hygromycin selection following co-cultivation with Agrobacterium tumefaciens improved the overall callus and shoot production. In vivo GFP fluorescence was detected to investigate the development of transgenic tissues using different hygromycin selection regimes. Higher transformation frequency was achieved when explants were continuously exposed to selection agents immediately following the pre-selection stage. Reducing the selection period followed by a non-selection stage increased the number of shoots, but these shoots were mostly non-transgenic. Thus, although less stringent selection, as expected, encouraged regeneration of shoots from calli, it did not improve transformation efficiency. Omitting selection altogether greatly reduced the efficiency of transformation. It was concluded that BAP is more suitable for normal shoot development, and that delayed selection followed by continuous selection results in higher transformation frequency. A significant improvement in regeneration of transgenic tomato through identification of key regeneration factors and robust screening is described, enabling high throughput genetic engineering in tomato.

AFLP Fingerprinting Analysis of Citrus Cultivars and Wild Accessions from Oman Suggests the Presence of Six Distinct Cultivars

Abstract A study was conducted to evaluate genetic relatedness of 27 citrus cultivars and 6 wild citrus accessions using AFLP fingerprinting. The 27 citrus cultivars belonged to Citrus sinensis, C. aurantifolia, C. aurantium, C. paradise, C. reticulata, C. limon, C. latifolia, C. maxima, C. limettoides, C. limetta, C. medica and C. Jambhiri. The wild cultivars were obtained from Oman while the other cultivars originated from Oman and other countries. AFLP analysis using 4 primer pair combinations resolved 910 polymorphic alleles. All citrus cultivars and accessions had low genetic diversity (H = 0.0281 to 0.1300), with the percent polymorphic loci ranging from 8 to 35%. Populations of the six wild citrus accessions showed a very low level of genetic diversity (< 0.0700). Cluster analysis of the 33 cultivars and accessions showed that they share a high level of genetic similarity (81‒99%; mean = 92%). The six wild accessions clustered into two main clusters, with the analysis indicating that the six wild accessions may make up six distinct cultivars. The study provides information on the phylogeny of citrus cultivars and citrus diversity in Oman, a country through which citrus moved in the past from Asia to different African and European countries. In addition, it shows that some distinct citrus cultivars are present in this part of the world.

English

Inter Simple Sequence Repeat (ISSR) markers were employed to reveal genetic diversity and relatedness among 27 chickpea (Cicer arietinum L.) cultivars in Ethiopia. Four di-nucleotide repeat primers amplified 24 clear and reproducible bands of which 22 were polymorphic (91.67%). The genetic variation among 27 chickpea cultivars including 12 kabuli and 15 desi verities is high; in which desi type exhibited a genetic diversity of 75% with Shannon index of 0.47, while the kabuli type chickpea had 91.67% genetic diversity and Shannon index of 0.50. Unweighted Pair Group of Arithmetic mean (UPGMA) dendrogram and NJ trees with Jaccard’s similarity coefficient showed three major clusters. This was also recovered by 3D principal coordinates analysis, although some cultivars were intermixed. Analysis of molecular variance (AMOVA) demonstrated highly significant (p < 0.001) genetic diversity within cultivars (97.71%) than among cultivars (2.29%). The distinct cultivars (Aererti, Tejie, Fetenech and Maryie) can serve as parents for future genetic resources conservation and Chickpea breeding program in Ethiopia. Key word: Chickpea cultivars, genetic diversity, ISSR markers, Ethiopia.

Effects of blackberries (Rupus sp.; cv. Xavante) processing on its physicochemical properties, phenolic contents and antioxidant activity.

Beneficial health effects are attributed to the wide array of polyphenols such as anthocyanins present in berries. Blackberries have been improved genetically to be cultivated in different climate such as Brazil. Thus, distinctive cultivars were created. However, antioxidant properties of these have not been evaluated. This study aimed to investigate the availability of phenolic compounds in Brazilian cultivar blackberries (cv. Xavante) after processing into purées, coulis and jam changes during storage. Physicochemical, total phenolic compounds (TPC), anthocyanins and antioxidant activity of frozen and processed food products were evaluated. The pH values of jam and frozen pulp increased to a greater extent during storage. Pureé A (70°C for 20min) showed the highest value for lightness and redness on day 1 with a decrease after 30days of storage. Redness values decreased to a greater extent for purée A, indicating less stable product over time whereas coulis presented optimal stability shown by the smaller color difference value. No differences in TPC were observed for frozen pulp, purée A, purée B, and coulis. Significantly lower amount of TPC was present in the jam indicating degradation of phenolic compounds upon heating and concentration process involved in jam making. An increase in antioxidant activity (ABTS assay) was observed in processed products after storage, which might be related to the development of new compounds with greater antioxidant activity. Therefore, processing of blackberries into food products is an alternative to prolong the accessibility of those fruits without extensive loss of antioxidant activities.

Unearthing Unevenness of Potato Seed Networks in the High Andes: A Comparison of Distinct Cultivar Groups and Farmer Types Following Seasons With and Without Acute Stress

Farmer seed systems are considered pivotal to adaptation to climate change and the on-farm conservation of agrobiodiversity in centers of crop origin. To better understand their distinct role, we conducted a multipronged analysis of potato seed exchange networks in Peru’s central Andes distinguishing between cultivar groups and farmer types following cropping seasons with and without acute stress. Cultivar groups involved (i) bred varieties, (ii) commercial floury landraces, (iii) non-commercial floury landraces (single cultivars), (iv) non-commercial floury landraces (mixed cultivars), and (v) bitter landraces. Farmer types involved (i) general farmers, (ii) seed specialists, and (iii) custodian farmers. Documentation of seed acquisition and provision without differentiating between farmers and cultivar groups may not accurately reflect the fine-grained dynamics underlying seed networks. To test this, a semi-structured survey of 336 households was conducted in 2014-2015 to study seed procurement in two research sites. Results confirm that seed networks are uneven and distinct for cultivar groups and farmer types. Commercial floury landraces and bred varieties were dominant when it came to frequency of transactions, volumes and overall availability. Bitter landraces represent an extreme opposite case, being procured infrequently. Non-commercial floury landraces represent an intermediate case as they are regularly procured in comparatively small volumes. The influence of general farmers and traders within seed networks is essential for overall seed access. The role of specialists and custodians is less omnipresent; yet, both fulfill a unique role. Specialists as providers of large volumes of certified seed of commercial floury landraces and bred varieties. Custodians as a source of diverse non-commercial floury landraces. Seed networks did re-organize following seasons with acute seed stress. A notable shift involved a contraction of seed networks within sub-regional clusters. Following stress, the directionality of seed provision versus acquisition inverted. While average seed volumes acquired per transaction nearly halved, farmers´ net seed acquisitions surpassed provisions in response to stress. We suggest that the self-regulatory capacity of farmer seed networks represents a strong safety net through which smallholders can respond to crop failure and seed stress. Seed system interventions aimed at genetic resources conservation or relief should build on these seed networks.

Transcriptomic landscape of Dendrobium huoshanense and its genes related to polysaccharide biosynthesis

&lt;em&gt;Dendrobium huoshanense&lt;/em&gt; has long been used to treat various diseases in oriental medicine. In order to study its gene expression profile, transcripts involved in the biosynthesis of precursors of polysaccharides, as well as mechanisms underlining morphological differences between wild and cultivated plants, three organs of both wild type and cultivated &lt;em&gt;D. huoshanense&lt;/em&gt; were collected and sequenced by Illumina HiSeq4000 platform, yielding 919,409,540 raw reads in FASTQ format. After Trinity de novo assembly and quality control, 241,242 nonredundant contigs with the average length of 967.5 bp were generated. qRT-PCR experiment on the selected transcripts showed the transcriptomic data were reliable. BLASTx was conducted against NR, SwissProt, String, Pfam, and KEGG. Gene ontology annotation revealed more than 40,000 contigs assigned to catalytic activity and metabolic process, suggesting its dynamic physiological activities. By searching KEGG pathway, six genes potentially involved in mannose biosynthetic pathway were retrieved. Gene expression analysis for stems between wild and cultivated &lt;em&gt;D. huoshanense&lt;/em&gt; resulted in 956 genes differentially expressed. Simple sequence repeats (SSRs) analysis revealed 143 SSRs with the unit size of 4 and 3,437 SSRs the size of 3. The obtained SSRs are the potential molecular markers for discriminating distinct cultivars of &lt;em&gt;D. huoshanense&lt;/em&gt;.

Genetic diversity and population structure of Indian soybean [Glycine max (L.) Merr.] revealed by simple sequence repeat markers

Genetic diversity in 90 Indian soybean cultivars was assessed using 45 SSR markers distributed on 20 soybean chromosomes. Forty-five SSR markers generated 232 alleles with an average of five alleles/locus. The observed frequencies of the 232 alleles ranged from 0.01 to 0.94 with an average of 0.19. The polymorphic information content (PIC) value of the SSR markers varied from 0.10 to 0.83 with an average of 0.61 and about 71% markers have a PIC value of >0.5. In this study, 54 rare alleles including 19 genotype specific alleles were also identified. The observed hetrozygosity for SSR markers ranged from 0 to 0.11 with a mean of 0.10. Cluster analysis grouped the 90 soybean cultivars into three major clusters and principal coordinates analysis (PCoA) results were similar to those of the cluster analysis. A combination of eight SSR markers successfully differentiated all 90 soybean cultivars. The population structure analysis distributed the 90 soybean genotypes into two populations with mean alpha (α) value of 0.1873. In AMOVA analysis, proportion of variation within population was high (88%), whereas only 12% occurred among populations. In cluster and structure analyses, most of the genotypes with similar pedigree were grouped together. Soybean cultivars DS228, MACS-13, LSb-1, Hardee, Improved Pelican, and Pusa-24 were the six most genetically distinct cultivars identified. The study reported a moderate genetic diversity in Indian soybean cultivars and findings would be useful to the soybean breeders in selecting genetically distinct parents for a soybean improvement program.

Coding SNPs analysis highlights genetic relationships and evolution pattern in eggplant complexes.

Brinjal (Solanum melongena), scarlet (S. aethiopicum) and gboma (S. macrocarpon) eggplants are three Old World domesticates. The genomic DNA of a collection of accessions belonging to the three cultivated species, along with a representation of various wild relatives, was characterized for the presence of single nucleotide polymorphisms (SNPs) using a genotype-by-sequencing approach. A total of 210 million useful reads were produced and were successfully aligned to the reference eggplant genome sequence. Out of the 75,399 polymorphic sites identified among the 76 entries in study, 12,859 were associated with coding sequence. A genetic relationships analysis, supported by the output of the FastSTRUCTURE software, identified four major sub-groups as present in the germplasm panel. The first of these clustered S. aethiopicum with its wild ancestor S. anguivi; the second, S. melongena, its wild progenitor S. insanum, and its relatives S. incanum, S. lichtensteinii and S. linneanum; the third, S. macrocarpon and its wild ancestor S. dasyphyllum; and the fourth, the New World species S. sisymbriifolium, S. torvum and S. elaeagnifolium. By applying a hierarchical FastSTRUCTURE analysis on partitioned data, it was also possible to resolve the ambiguous membership of the accessions of S. campylacanthum, S. violaceum, S. lidii, S. vespertilio and S. tomentsum, as well as to genetically differentiate the three species of New World Origin. A principal coordinates analysis performed both on the entire germplasm panel and also separately on the entries belonging to sub-groups revealed a clear separation among species, although not between each of the domesticates and their respective wild ancestors. There was no clear differentiation between either distinct cultivar groups or different geographical provenance. Adopting various approaches to analyze SNP variation provided support for interpretation of results. The genotyping-by-sequencing approach showed to be highly efficient for both quantifying genetic diversity and establishing genetic relationships among and within cultivated eggplants and their wild relatives. The relevance of these results to the evolution of eggplants, as well as to their genetic improvement, is discussed.

Kinetics of the Polyphenolic Content and Radical Scavenging Capacity in Olives through On-Tree Ripening

Olive fruits, as well as their corresponding oil, represent an interesting source of phytochemicals, mainly phenolic compounds, which arise as secondary metabolites, resulting from the plant’s response to biotic and abiotic stresses. Therefore, olive fruits from three distinct cultivars (“Cobrançosa,” “Galega Vulgar,” and “Picual”) grown in Portugal and displaying different degree of resistance to biotic and abiotic stresses have been studied in relation to the concentration of total phenolic compounds, orthodiphenols and flavonoids, besides antioxidant capacity (DPPH, ABTS, FRAP, and ORACFL), in three maturation stages and two distinct harvest seasons (2012-2013). Generally, a decrease of all phenolic contents throughout the maturation stages has been observed, while, concerning cultivar, green olives of “Cobrançosa” showed the highest values for all contents assessed, denoting a strong influence of the genetic background. The same trend has not been observed regarding antioxidant activity, since Cobrançosa and Galega Vulgar cultivars presented the highest values only for the DPPH and ORACFL assays. Moreover, multivariate analyses pointed to the preponderance of the cultivars’ phenolic composition in the semiripe stage for the resistance to biotic stress, with “Galega” the most susceptible cultivar, presenting the lowest contents at this maturation stage, whereas “Picual” displayed the most pronounced phytochemical response.

A 3-Year Adaptation Study of Three Distinct Grapevine Cultivars under Midwestern Field Conditions

ABSTRACTSimultaneous responses of American (Concord), European (Pinot Noir), and American-European hybrid (Traminette) cultivars to seasonal and diurnal variation in field environmental conditions were assessed to propose suitable cultivars for potential use for selection and breeding in grapevines in dry areas. ‘Pinot Noir’ had higher gas exchange parameters, higher water potential, and chlorophyll fluorescence, while ‘Concord’ had the lowest values in all three seasons and experienced moderate stress by the end of each season. The dry conditions in 2005 caused water potential to decline sharply compared to values recorded in 2004 and 2006. ‘Pinot Noir’ and ‘Traminette’ exhibited a mild stress, while ‘Concord’ exhibited a moderate stress in 2006. Photosynthetic rate decreased slightly during the summer with a slight recovery at the beginning of September, and did not differ across the seasons among cultivars. Stomatal conductance followed the same pattern. However, in both 2004 and 2005, stomatal conductance dropped sharply late in the season because of frequently occurring high temperatures that were greater than 32 °C. Maximum morning values of Fv/Fm were within the optimal range. The study suggests the presence of marginal photoinhibition during mid-summer in Concord cultivars, because no full recovery of photochemical efficiency early in the evening was observed. The European cultivar (Pinot Noir) and the American-European hybrid (Traminette) are more adapted to field conditions in Kansas than Concord cultivars. However, high cold-mortality of Pinot Noir due to high sensitivity to cold winter temperature makes the hybrid cultivars the most suitable cultivar for Midwest regions with relatively cold winters.

Genetic diversity of pepper (Capsicum spp.) germplasm resources in China reflects selection for cultivar types and spatial distribution

Pepper (Capsicum spp.) is an important vegetable crop in the world. Now the pepper in China contributes one-third of the world's peppers production. Genetic diversity of the pepper germplasm of China is expected interesting to know. To explore the structure of genetic diversity in Chinese pepper germplasm resources and possible relationship with cultivar types or geographic origin, we sampled and compared 372 GenBank pepper accessions (local cultivars and landraces) from 31 provinces, autonomous regions and municipalities of China and 31 additional accessions from other countries. These accessions were genotyped using 28 simple sequence repeat (SSR) markers spanning the entire pepper genome. We then investigated the genetic structure of the sampled collection using model-based analysis in STRUCTURE v2.3.4 and examined genetic relationships by the unweighted pair-group method of mathematical averages (UPGMA) in MEGA. In addition to geographic origin, we evaluated eight plant and fruit traits. In total, 363 alleles were amplified using the 28 SSR primers. Gene diversity, polymorphism information content and heterozygosity of the 28 SSR loci were estimated as 0.09–0.92, 0.08–0.92 and 0.01–0.34, respectively. The UPGMA cluster analysis clearly distinguished Capsicum annuum L. from other cultivated pepper species. Population structure analysis of the 368 C. annuum accessions uncovered three genetic groups which also corresponded to distinct cultivar types with respect to the plant and fruit descriptors. The genetic structure was also related to the geographic origin of the landraces. Overall results indicate that genetic diversity of Chinese pepper landraces were structured by migration of genotypes followed by human selection for cultivar types in agreement with consumption modes and adaptation to the highly diversified agro-climatic conditions.

Advances in Faba Bean Genetics and Genomics.

Vicia faba L, is a globally important grain legume whose main centers of diversity are the Fertile Crescent and Mediterranean basin. Because of its small number (six) of exceptionally large and easily observed chromosomes it became a model species for plant cytogenetics the 70s and 80s. It is somewhat ironic therefore, that the emergence of more genomically tractable model plant species such as Arabidopsis and Medicago coincided with a marked decline in genome research on the formerly favored plant cytogenetic model. Thus, as ever higher density molecular marker coverage and dense genetic and even complete genome sequence maps of key crop and model species emerged through the 1990s and early 2000s, genetic and genome knowledge of Vicia faba lagged far behind other grain legumes such as soybean, common bean and pea. However, cheap sequencing technologies have stimulated the production of deep transcriptome coverage from several tissue types and numerous distinct cultivars in recent years. This has permitted the reconstruction of the faba bean meta-transcriptome and has fueled development of extensive sets of Simple Sequence Repeat and Single Nucleotide Polymorphism (SNP) markers. Genetics of faba bean stretches back to the 1930s, but it was not until 1993 that DNA markers were used to construct genetic maps. A series of Random Amplified Polymorphic DNA-based genetic studies mainly targeted at quantitative loci underlying resistance to a series of biotic and abiotic stresses were conducted during the 1990's and early 2000s. More recently, SNP-based genetic maps have permitted chromosome intervals of interest to be aligned to collinear segments of sequenced legume genomes such as the model legume Medicago truncatula, which in turn opens up the possibility for hypotheses on gene content, order and function to be translated from model to crop. Some examples of where knowledge of gene content and function have already been productively exploited are discussed. The bottleneck in associating genes and their functions has therefore moved from locating gene candidates to validating their function and the last part of this review covers mutagenesis and genetic transformation, two complementary routes to validating gene function and unlocking novel trait variation for the improvement of this important grain legume.

Sorting out the value of spectroscopic tools to assess the Colletotrichum acutatum impact in olive cultivars with different susceptibilities

The olive tree (Olea europaea L.) can be affected by Colletotrichum acutatum, causing a loss of yield and quality of the final products, whilst the incidence of this fungal infection depends on several factors, including cultivar susceptibility. Thus, the effect of C. acutatum infection in cultivars displaying different susceptibilities to this fungal disease (‘Galega Vulgar’ ‐ susceptible, ‘Cobrançosa’ ‐ moderately susceptible, ‘Picual’ ‐ tolerant) has been assessed through spectrophotometric methods and HPLC, while the FTIR spectra of the cuticles have been concomitantly registered, resorting to the ATR accessory.With the support of multivariate analysis, these spectra allowed to discriminate olives with distinct infection times, besides retrieving evidences concerning the different susceptibility of each cultivar, while these observations were reinforced by the spectrophotometric and chromatographic methods. Furthermore, the assessment of the phenolic profile evidenced individual compounds in the distinct cultivars, so as their variations in response to the fungal infection.

Deciphering population structure and diversity inLuffa cylindrica(L.) M. Roem. using morphological and sequence-related amplified polymorphism markers

Luffa cylindrica(L.) M. Roem. is an underutilized vegetable and a potential biodiesel crop for future. Its fruits are edible and used as vegetable. To aid in the selection of lines for breeding, genetic variation and structure of ten populations ofL. cylindricawere determined with three morphological characters and 23 sequence-related amplified polymorphism (SRAP) markers. All the three morphological characters were found diverse among 45 accessions. The SRAP primers produced a total of 177 bands, out of which 129 were polymorphic. Informative markers assessed by different measures (polymorphism information content = 0.18, marker index = 1.26, resolving power = 2.87) will direct the selection of primers for cultivar identification inL. cylindrica. Low level of genetic differentiation among populations and higher level within populations (Gst= 0.4073,Nm= 0.7277,He= 0.124,I= 0.20) was detected that might be due to cross-pollinated nature ofL. cylindrica. The clustering pattern obtained through dendrogram and principal coordinate analysis was loosely concordant with the geographical distribution. The Bayesian structure analysis indicated an admixture type of population distribution. The results designate that SRAP and morphological markers are informative for characterization ofL. cylindricaand identification of distinctive cultivars.

Discrimination and characterisation of extra virgin olive oils from three cultivars in different maturation stages using Fourier transform infrared spectroscopy in tandem with chemometrics

A methodology based on Fourier transform infrared (FTIR) spectroscopy, combined with multivariate analysis methods, was applied in order to monitor extra virgin olive oils produced from three distinct cultivars on different maturation stages. For the first time, this kind of methodology is used for the simultaneous discrimination of the maturation stage, and different cultivars.Principal component analysis and discriminant analysis were utilised to create a model for the discrimination of olive oil samples. Partial least squares regression was employed to design calibration models for the determination of chemical parameters. The performance of these models was based on the multiple coefficient of determination (R2), the root mean square error of calibration (RMSEC) and root mean square error of cross validation (RMSECV). The prediction models for the chemical parameters resulted in a R2 ranged from 0.93 to 0.99, a RMSEC ranged from 1% to 4% and a RMSECV from 2% to 5%.It has been shown that this kind of approach allows to distinguish the different cultivars, and to clearly discern the different maturation stages, in each one of these distinct cultivars.Furthermore, the results demonstrated that FTIR spectroscopy in tandem with chemometric techniques allows the creation of viable and accurate models, suitable for correlating the data collected by FTIR spectroscopy, with the chemical composition of the EVOOs, obtained by standard methods.

Iron toxicity in field-cultivated rice: contrasting tolerance mechanisms in distinct cultivars

Iron toxicity is a major nutritional disorder in irrigated and rainfed waterlogged rice. To elucidate mechanisms involved in tolerance to iron toxicity, plants from one cultivar susceptible to iron toxicity (BR-IRGA 409) and two tolerant cultivars (EPAGRI 108 and EPAGRI 109) were grown in the field, at an iron-toxic site and at a control site in Southern Brazil. We evaluated chlorophyll concentrations, carbonyl concentrations, iron concentrations in leaves and roots, antioxidative enzyme activities (SOD, APX, CAT, GR and DHR), concentrations of reduced and oxidized forms of ascorbate and glutathione, and gene expression profile of four SOD genes in rice leaves. Only plants from the susceptible cultivar showed symptoms of iron toxicity when grown at the iron-toxic site, accumulating high levels of iron in leaves. EPAGRI 108 plants had the lowest iron concentration in leaves and reached the highest iron concentration in the root symplast, suggesting that the capacity to safely store iron in root cells and to limit iron translocation to shoots could be a tolerance mechanism in this cultivar. Plants from the susceptible cultivar showed higher APX activity as well as higher DHA and GSSG concentrations. Plants from the EPAGRI 109 cultivar accumulated high iron levels in leaves, and showed the highest SOD, GR and DHR activities when grown in the iron-toxic site. The same cultivar also showed the highest expression of three out of four SOD genes tested. Therefore, the two tolerant cultivars seem to rely on different mechanisms to deal with iron toxicity in field conditions: limiting iron translocation to the shoot or inducing enzymes-dependent leaf tolerance.

Genetic structure of the Greek olive germplasm revealed by RAPD, ISSR and SSR markers

The olive is globally considered as one of the most significant crops, with more than 1200 distinctive cultivars and an abundant number of wild forms. Greece, the third largest producer worldwide, has been considered a secondary centre of domestication and its genetic recourses are potentially valuable for olive breeding. In the current study, the genetic diversity of an extended Greek olive germplasm collection (101 accessions) was revealed using RAPD, ISSR and SSR markers in an attempt to explore the genetic relationships among them, and comprehend how genetic variability is partitioned between the Greek germplasm. A Bayesian model-based clustering method was employed and allocation of genotypes into defined gene pools according to genetic and geographic criteria was detected. Genealogies detected by Median-Joining coalescent simulations, classified all genotypes into a complex network. Both linear and reticulate ties among the Greek olive cultivars were revealed. Hence, data suggested that both sexual and vegetative propagation have contributed to the evolution of the Greek olive germplasm. Furthermore, clustering of olive cultivars was correlated to their primarily usage (table or oil producing) and fruit size. Finally, Greek olive cultivars are characterized providing a useful clarification on synonyms and homonyms, facilitating the identification of duplicates.

Keanekaragaman Kultivar Salak Pondoh di Banjarnegara

Snake fruit ( Salacca zalacca (Gaertner) Voss) is originated from Indonesia. The aim of this study was to find out the cultivar diversity of salak pondoh in Banjarnegara, and to determine the similarity relatiinshipa between cultivars pondoh in Banjarnegara. The method used was exploratory survey with purposive random sampling. Morphological characteristics observed included 50 characters in the form of stems, leaves, flowers, fruits, seeds, and spines. Samples were taken at 5 districts namely Madukara, Banjarmangu, Sigaluh, Pagentan and Banjarnegara. The result of this research showed that there were six cultivars of Salacca zalacca namely cultivars ‘Pondoh Nglumut’, ‘Linting’, ‘Ketek’, ‘Manggala’, ‘Madu’, and ‘Super’. Whereas in S . zalacca 'Pondoh Ketek' has various number of seeds in the fruit. The most closely related cultivars were ‘Pondoh Nglumut’ and ‘Super’. The most distinct cultivars were S . zalacca ‘Manggala’ and ‘Ketek’.