Summary We present the results of a histochemical study comparing seedlings of races C and D of Orobanche cumana Wallr. (syn. O. cernua Loefl.) attacking sunflower (Helianthus annuus L.) in southern Russia. Three groups of O. cumana seedlings were distinguished according to the peroxidase content of the cells in the radicles: (1) those with neither extracellular nor intracellubr peroxidase and whose radicles have a smooth apex (these were classified as non‐infective): (2) those with a high peroxidase content of the nuclei and the cytoplasm layer adjacent to the cell wall, as well as excretion of peroxidase from the apex of the radicles: (3) those with a similarly high peroxidase activity in the parasite cells, but without extracellular excretion. The apices of the radicles of the last two groups are swollen. It is suggested that these belong to O. cumana races C and D respectively. The extracellular peroxidase in O. cumana race C reacts with phenolic compounds, which are lignin precursors of the host, resulting in host resistance due to the formation of lignin layers in sunflowers possessing the Or3 gene for resistance. The absence of extracellular peroxidase in O. cumana race D prevents lignin formation and enables the parasite to attach to the host vascular system. Comparison of these data with the information on the earlier O. cumana races A and B, and older sunflower cultivars, points to a crucial role of peroxidase in the process of breeding new sunflower cultivars and the evolution of new O. cumana races.

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The molecular genetic diversity of the broomrape (O. cumana) populations, parasitizing on sun flower in Russia, Romania and Kazakhstan, was studied with codominant microsatellite markers. By means of cluster analysis, the populations of broomrape were divided into two clusters, regardless of their racial com position. In the first cluster, 19 samples from Russia and Kazakhstan, representing one gene pool are grouped; the second cluster consisted of five populations from Romania, united in another pool. According to Nei, the genetic distance between the clusters was 0.137. The analysis of molecular variance revealed that 22% of total variance were caused by differences between the genetic pools and 78% appeared due to differences between the samples within the each gene pool. The pairwise comparisons performed by Wright's statistics showed that the differences between these two gene pools are sufficient (F st = 21.9%) in order to make the conclusion about the existence of small genetic differentiation between the pools. The descriptive population genetic sta tistics for each pool indicate that the broomrape populations from Russia and Kazakhstan are characterized by a higher level of intrapopulation diversity than the populations from Romania.

Broomrape (Orobanche cumana Wallr.) is an obligate parasite of higher plants, which affects sunflower in many countries, cultivating this crop. For the past decades, it is noted the formation of new highly virulent biotypes of broomrape and their spreading to other areas. In our work we studied the molecular genetic diversity of broomrape populations of O.cumana, parasitizing on sunflower in Russia, Romania, and Kazakhstan, by using codominant microsatellite markers. During cluster analysis, the broomrape populations are divided into two clusters, regardless of their racial composition. One cluster grouped 19 samples from Russia and Kazakhstan, and the other -5 populations from Romania. The genetic distance between clusters according to Nei was 0.137. The analysis of molecular variance (AMOVA) revealed that 22% of genetic variability was due to differences among the gene pools and 78% was due to differences within the gene pools. Pairwise comparisons made using Wright's statistics showed that the differences between these two gene pools are sufficient (Fst ¼ 0.219) to state the existence of a small genetic differentiation between them. Descriptive population genetic statistics for each of the two pools showed that the broomrape populations from the former Soviet Union countries are characterized by a higher level of intrapopulation diversity than the populations from Romania. Molecular genetic differences between broomrape populations parasitizing on sunflower on the post-Soviet territory and in *Corresponding author: Saida Guchetl, Laboratory of Immunity and Electrophoresis, All-Russia Research Institute of Oil Crops by the name of V.S. Pustovoit, 17 Filatova str.,

Backgrand. Lateralized periodic discharges (LPDs) are infrequent electroencephalograph (EEG) findings, and may present in ictal or interictal form. They are regarded as potential electrophysiologic signs of convulsive or nonconvulsive status epilepticus (NCSE). We report four patients who presented with NCSE and one who presented with convulsive status epilepticus in the postictal period, characterized by LPDs in EEG recordings in the first year after stroke. Material and methods. We prospectively evaluated patients who clinically presented with status epilepticus associated LPDs between March 2014 and March 2015. We investigated patients that presented with a new stroke occurrence. We excluded the other LPD etiologies. EEG studies of five patients (two men) who were admitted to our emergency unit with confusion, three of whom had visual symptoms; four were treated for NCSE as diagnosed with LPDs. The fifth patient had convulsive status epilepticus with LPD in the postictal period. Results and Discussion. None of the five patients, who were aged between 68 and 92 years, showed any etiologic factor other than a history of cerebrovascular disease (CVD). Magnetic resonance imaging studies of the patients revealed old infarcts and transitional diffusion restrictions. The clinical and EEG findings decreased substantially upon antiepileptic drug treatment. Herein, we illustrate the first patient who had confusion, visual hallucinations, and ictal and interictal LPD in her consecutive EEGs. Conclusions. CVDs may pave the way for LPDs in patients with a history of stroke because CVDs cause structural brain damage. Patients who present with a similar clinical profile and imaging signs of stroke should be checked for NCSE, particularly in the presence of LPDs in EEGs.