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A germplasm collection of red clover (Trifolium pratense L.) and seven related species was evaluated in greenhouse tests for resistance to Meloidogyne arenaria (Neal) Chitwood, M. hapla Chitwood, M. incognita (Kofoid & White) Chitwood, and M. Javanica (Treub) Chitwood. Plants were rated for root galling severity and nematode egg production at eight weeks after inoculation with 1500 nematode eggs. A resistance index, RI = √(gall2; + egg2;), was generated to assess the plants' reaction to nematode infection as immune, highly resistant, resistant, moderately resistant, intermediate, moderately susceptible, susceptible, or highly susceptible. More than 98% of red clover accessions were intermediately to highly susceptible to all four root-knot nematode species. Only one accession, PI 271627 introduced from India, had a moderate resistance level to the four nematodes tested. About one third of the T. medium accessions were resistant or highly resistant to M. arenaria, M. incognita, and M. javanica whereas more than 50% of the T. alpestre accessions were highly resistant or immune to all four nematodes species. Genetic factors for resistance to root-knot nematode could be introduced into T. pratense through interspecific hybridization with T. medium and/or T. alpestre

Using the 8 specific primer pairs based on the conserved motifs of plant resistance genes, the plant disease resistance gene analog polymorphisms (RGAPs) in 15 wild emmer wheat (Triticum dicoccoides) populations from Israel had been detected. High genetic variations at the RGAP loci were observed in T. dicoccoides populations. A total of 254 discernible bands were obtained among 115 accessions, and 192 bands (75.6%) were polymorphic. Each genotype had a unique banding profile, and the genetic similarity coefficient ranged from 0.094 to 0.862. In T. dicoccoides, the proportion of polymorphic loci (P), the genetic diversity (He) and Shannon’s information index were 0.756, 0.362 and 0.541, respectively. The proportion of polymorphic loci (P) per population averaged 0.732 (range: 0.515–0.932); genetic diversity (He) averaged 0.271 (range: 0.212–0.338); and Shannon’s information index averaged 0.404 (range: 0.310–0.493). The coefficients of genetic distance (D) among populations averaged 0.107 (range: 0.043–0.178), and the results of Mantel test (r = 0.168, P = 0.091) showed that the estimates of genetic distance were geographically independent. Neighbor-joining cluster analysis suggested that the genetic relationships of T. dicoccoides populations were associated with their ecogeographic distribution. The hierarchical analysis of molecular variance (AMOVA) and the coefficient of gene differentiation (G ST ) values revealed that most of the variations were presented within populations, although significant differences among populations and regions were also detected. The values of P and Shannon’s information index were negatively correlated with the two factors: Tdd (day–night temperature difference) and Ev (mean annual evaporation), whereas they were positively correlated with one water factor: Rn (mean annual rainfall). The correlation matrix between He in the RGAPs and geographic variables contained 20 significant (P < 0.05) correlations. The present study established that T. dicoccoides in Israel had a considerable amount of genetic variations at RGAP loci at least partly correlated with ecological factors.

Marrubium L., is a problematic genus of Lamiaceae family with approximately 40 taxa that some of its species grow in Iran. In the current study, we studied infrageneric taxonomic relationships among six Iranian Marrubium species using morphological and anatomical traits, and molecular genetic techniques, including inter simple sequence repeats (ISSR), chloroplast DNA (cpDNA) and nuclear ribosomal internal transcribed spacer (ITS). We investigated five individuals per each species. Most of the studied qualitative and quantitative morphological characteristics differed significantly (P ≤ 0.001) among these species, and we found five morphotype groups in the PCA plot of morphological traits. Leaf blade anatomical structure was dorsi-ventral in all species. Meanwhile, we observed a significant variation in most of the studied anatomical variables. Based on anatomical features, these species were clustered into three groups. Results of ISSR study revealed that the total genetic diversity at the species level (Ht) was higher than within each species (Hs). These findings were supported by the results of AMOVA test, Gst and Nm values. According to STRUCTURE analysis and Nei's genetic distance, these species were divided into 5 genotype groups. The studied species were clustered separately in cpDNA and ITS trees of phylogenetic studies. We observed a high level of infraspecific divergence in the evaluated species. In addition, the employed taxonomical markers have enough potential to separate the investigated species. However, the clustering patterns of the species based on the examined techniques were not the same, except those for M. parviflorum Fisch. & C.A. Mey., and M. crassidens Bioss., that were clustered closely in most cases. It can be concluded that the evaluated species revealed a taxonomically complex group resulting from high infraspecific variation, polyploidy and hybridization.

Fusarium head blight (FHB), caused by Fusarium graminearum Schwabe [telomorph = Gibberella zeae (Schw.) Petch], is a persistent threat to wheat production. Development of resistant varieties and identification of germplasm carrying new sources of resistance is necessary to preserve grain quality and yield. Resistance to FHB has been identified both within the gene pools of cultivated wheat and wild wheat relatives. In this study, a collection of the D genome species, Aegilops tauschii Coss. was evaluated for resistance to FHB. A total of 109 accessions of Ae. tauschii Coss. subsp. tauschii and Ae. tauschii Coss. subsp. strangulata (Eig) Tzvelev were infected with F. graminearum by single floret inoculation. Disease severity was rated as the percentage of infected spikelets at 21 days post-inoculation. A strong relationship was identified between geographical origin of Ae. tauschii accessions and FHB resistance. Generally, accessions from areas receiving high levels of annual rainfall were resistant whereas accessions from areas of low rainfall, more susceptible to FHB. High levels of FHB resistance were identified in accessions collected from regions bordering the Caspian Sea. The majority of accessions from arid regions were susceptible to FHB. The resistant germplasm identified in this study will support long-term FHB resistance breeding efforts.

A total of 158 almond accessions representative of the diversity of almond across the five continents were included for analysis using 17 microsatellite polymorphic markers. Genetic relationships among genotypes were estimated using cluster analysis, allowing their differentiation in two main groups, one with the domesticated almond cultivars and selections and the other with all wild Prunus species close to almond. The unweighted pair group method average tree drawn from this analysis classified the genotypes according to their geographical origin, confirming the particular evolution of different almond ecotypes. Structure analysis showed a strong subpopulation structure and linkage disequilibrium decaying with increasing genetic linkage distance. Analysis of molecular variance confirmed that most of the genetic variability was within populations. Therefore the connection structure between the different populations and the possible bottlenecks in the expansion of almond cultivars could be established.

Die monographische Darstellung der GaterslebenerAegilops-Kollektion (Hammer 1980b) wird mit den Ergebnissen der Untersuchungen zum Resistenzverhalten gegenüberErysiphe graminis, Puccinia graminis, Puccinia striiformis, Puccinia recondita, Septoria nodorum undPseudocercosporella herpotrichoides fortgesetzt Gegenüber allen Krankheiten konnten resistente Sippen nachgewiesen werden. Ihr möglicher Einsatz in Züchtungsprogrammen wird kurz diskutiert. “Safe storage is of course essential, but the process of evaluation and utilization will become ever more important.” (1983)

Triticum tauschii (Coss.) Schmalh. (Aegilops squarrosa auct. non L., 2n=2x=14, DD genome) with its diverse range of accessions and distribution provides a unique opportunity for exploiting novel genetic variability for wheat (T. aestivum L.) improvement associated with biotic/abiotic stress factors. From our working collection of 490 T. tauschii accessions we have so far produced 430 different synthetic hexaploids (2n=6x=42, AABBDD) resulting from the chromosome doubling of Triticum turgidum L. s. lat. x T. tauschii F1 hybrids (each synthetic involving a different T. tauschii accession). We present here our results on hybrid production, plantlet regeneration, cytology, colchicine induced doubling of the 2n=3x=21 chromosome F1 hybrids, seed increase of the doubled progeny and screening for a biotic stress; Cochliobolus sativus Ito and Kuribay (syn. Helminthosporium sativum Pamm. King and Bakke); of 250 of these synthetic hexaploid (2n=6x=42) amphiploids. Application of the direct crossing methodology involving susceptible T. aestivum cultivars with resistant T. tauschii accessions is also alluded to.

Voraussetzung und Wege, die zur Domestikation führten, werden untersucht und die Ergebnisse dieses Evolutionsprozesses diskutiert. Schon von Beginn an läßt sich eine Zweiteilung in Kulturpflanzen des großflächigen Feldbaues, die über das Saatgut vermehrt werden und bei denen die Massenauslese vorherrscht, und Kulturpflanzen des kleinflächigen Gartenbaues, bei denen Formen der vegetativen Vermehrung und Individualauslese überwiegen, verfolgen. Feldbau führt zu ausgewogenen Pflanzenbeständen mit einem guten allgemeinen Ertragspotential, ohne daß sich einzelne Merkmale oder Merkmalsgruppen durch eine überdimensionale Entwicklung auszeichnen. Gartenkultur resultiert oft in beträchtlichen Merkmalsabänderungen (allometrisches Wachstum). An drei Beispielen werden Ablauf und Ergebnisse der Domestikation untersucht.Hordeum vulgare (primäre Kulturpflanze) undPapaver somniferum (sekundäre Kulturpflanze) sind Vertreter des Feldbaus. Die Bedingungen des Feldbaus bieten günstige Voraussetzungen für eine unbewußte und indirekte Domestikation von Pflanzen, die später selbst zu Kultursippen werden können (sekundäre Kulturarten). Aber auch Unkräuter, die für eine spätere Nutzung nicht in Frage kommen, werden hier indirekt domestiziert. Unter den Bedingungen der Gartenkultur dominiert die bewußte und direkte Selektion. Als Beispiel wird hier die Domestikation vonLycopersicon esculentum untersucht. Obwohl der Ablauf der Domestikation in Abhängigkeit von den Arten recht kompliziert sein kann und eine Fülle von unterschiedlichen Formen hervorgebracht wird, gestattet das gesetzmäßige Auftreten von Gruppen spezifischer Kulturpflanzenmerkmale die Postulierung des Domestikationssyndroms. Eine Abgrenzung der Domestikationserscheinungen von ähnlichen Merkmalsentwicklungen bei kolonisierenden und ruderalen Arten wird vorgenommen. Die Kulturpflanzen sind Produkt der Kulturentwicklung der Menschheit ebenso wie die Haustiere. Parallelen in der Phänomenologie bei Kulturpflanzen und Haustieren lassen auch bei diesen das Domestikationssyndrom erkennen. Informationen bekannt und besonders die Zeit nach der Wiederentdeckung der Mendelschen Vererbungsgesetze brachte neue Erkenntnisse zur Genetik und Phylogenie der Kulturpflanzen. Der Anstoß zur weiteren Durchdringung des Domestikationsphänomens wurde durch die Untersuchungen vonEngelbrecht (1916) und besonders vonThellung (1925, 1930) gegeben.Thellung, als ausgezeichneter Kenner der Adventivflora, mußte genaue Kriterien zur Unterscheidung von Kultur-, Unkraut- und Wildpflanzen in ihren vielfältigen Wechselwirkungen entwickeln und lieferte ein zusammenfassendes Konzept (Thellung 1930), das die eigentliche Grundlage für eine Phänomenologie der globalen Erscheinungen der Domestikation bildet. VonFaegri (1981) wurde dafür der Begriff Domestikationssyndrom1 eingeführt.

The Physalis angulata L. species, better known in Brazil as camapu, is mostly found in the northern regions of the country. It is used for human consumption, in medicine and as an ornamental plant. Because of its potential economic and nutritional value, research was carried out to know the genetic variability of fruit traits. Repeatability is the fraction of phenotypic variation that is due to permanent genetic and environmental factors. The estimation of repeatability coefficient allows breeders to estimate the ideal number of measurements for a trait. This work aims to evaluate the performance of P. angulata accessions and to estimate the coefficients of repeatability and minimum number of repetitions for fruit characteristics in two environments and two seasons. The present work was conducted at the Horto Florestal Experimental Unity of Universidade Estadual de Feira de Santana, using seven accessions of P. angulata from the Germplasm Collection of LAGEM/UEFS. Four experiments were conducted, two in the experimental field and two in the greenhouse, in an entirely randomized design with 24 replicates, using five accessions in the first two experiments, and six accessions in the last two in each environment, totaling 120 and 144 experimental units, respectively. The characteristics number of fruits per plant (NFP), soluble solids content (SSC), longitudinal diameter (LFD) and transversal diameter (TFD) of the fruits, and average fruit mass (AFM) were evaluated. Data were submitted to analysis of variance (ANOVA) and estimates of repeatability coefficients were obtained by ANOVA, principal components (PC), and structural analysis (SA) methods. There was significant variance among accessions for the characteristics LFD, TFD, AFM and SSC in the experimental field, and for TFD, LFD NFP in the greenhouse. Heritability ranged from 61.63 to 91.91% in both environments. PC showed the highest estimates of repeatability coefficient. The repeatability and determination coefficients by PC analysis ranged from TFD (r = 0.51; R2 = 96.19%) to SSC (r = 0.72; R2 = 98.47) in the field, and from NFP (r = 0.40; R2 = 93.92%) to LFD (r = 0.51; R2 = 79.38%) in the greenhouse. Twenty measurements can achieve 95 and 90% reliability for experimental field and greenhouse experiments, respectively, for the evaluated traits.