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Wheat, one of the world's major crops, is seriously affected by fungal diseases, especially in regions with high moisture and moderately warm temperatures. This paper reviews various molecular and conventional techniques that are used to identify genotypes with resistance alleles associated with Fusarium head blight (FHB) diseases. Quantitative trait loci (QTL) type II, designated as Fhb1, are frequently applied in plant breeding, and the newly recognized genes related to resistance to this fungal disease give extra insights into marker-assisted selection (MAS). Molecular markers are robust tools that may be routinely used in MAS for the mapping of resistance genes in crop breeding. FHB resistance is polygenic, and different resistance genes could be conveyed into a single genotype by MAS, which might ensure greater resistance to FHB disease. In conclusion, different researchers have used various techniques to control FHB resistance, such as MAS, gene pyramiding (through backcross), and molecular markers (association with resistance QTLs or genes).

Ornamental sunflowers are widely cultivated for use as cut flowers and/or as garden plants. The objective of the study was to investigate breeding values of new F₁ ornamental sunflower hybrids using incomplete diallel crossing of four ornamental inbred lines: Heliopa, Talia, Iskra and Neoplanta. Six traits important for ornamental market use were studied. Additive gene effects prevailed in most tested traits except for lateral floral diameter and duration of lateral flowering, which exhibited non-additive effects. The results indicated that the Talia × Neoplanta hybrid combination was the most promising for cut flowers due to long and strong branches, relatively big lateral flowers while Heliopa × Iskra and Heliopa × Talia hybrids were suitable for use as garden plants due to strong plant habit, long flowering time and desirable plant height. The results obtained from this study will be helpful for further ornamental sunflower breeding.

In the past decade, next-generation sequencing (NGS) platforms have changed the impact of sequencing on our knowledge of crop genomes and gene regulation. These techniques are today acquiring a great potential in metagenomic and agrigenomic research while showing prospects for their utilization in plant breeding. We can now obtain new and beneficial information about gene regulation on the cellular as well as whole-plant level through RNA-sequencing and subsequent expression analyses of genes participating in plant defence reactions to pathogens and in abiotic stress tolerance. NGS has facilitated the development of methods to genotype very large numbers of single-nucleotide polymorphisms. Genotyping- by-sequencing and whole-genome resequencing can lead to the development of molecular markers suited to studies of genetic relationships among breeding materials, creation of detailed genetic mapping of targeted genes and genome-wide association studies. Plant genotyping can benefit plant breeding through selection of individuals resistant to climatic stress and to pathogens causing substantial losses in agriculture.

This study investigated changes in stem and spike characteristics resulting from breeding in Iranian wheat cultivars, and their relationship with grain yield. Eighty-one wheat cultivars released between 1930 and 2006 were examined under well-watered (WW) and terminal drought stress (DS) conditions in Karaj during 2007-2008 and 2008-2009 and under WW condition at Parsabad in Moghan region during 2010-2011. A genetic improvement over time in stem specific weight (SSW) along with significant positive correlations between this trait and grain yield were found at Karaj under DS conditions and at Parsabad, suggesting that SSW could be used as an indirect selection criterion for yield in these environments. Time-dependent changes in spike dry weight showed that the magnitude of partitioned photoassimilates to the spike during the phase anthesis - 16 days after anthesis (16 DAA) was not changed by breeding. However, during the 16 DAA ‒ maturity phase, modern cultivars had more photoassimilates allocated to the spike than the old ones. This suggests that the sink is more limited during early grain growth than during the end of grain filling.

In 2012-2015 the virulence of the wheat leaf rust (Puccinia triticina Eriks.) population was studied on Thatcher near-isogenic lines with Lr1, Lr2a, Lr2b, Lr2c, Lr3a, Lr9, Lr10, Lr11, Lr13, Lr15, Lr17, Lr19, Lr21, Lr23, Lr24, Lr26 and Lr28. Samples of leaf rust were obtained from different parts of the Czech Republic. A total of 163 wheat leaf rust isolates were analysed. No virulence for the resistance gene Lr9 was found. Virulence for Lr19 was found only in one isolate in 2015. A lower frequency of virulence to Lr24, Lr2a, 2b, 2c and Lr28 was also observed. The presence of Lr10, Lr24, Lr26, Lr28 and Lr37 in registered cultivars was detected by polymerase chain reaction (PCR) molecular markers.

The contamination of bulk samples of cow's raw milk (n = 491) by psychrotrophic lipolytic bacteria (PLiBC), total count of psychrotrophic bacteria (PBC) and mesophilic bacteria (TBC) was monitored for two years on eight dairy farms and the correlations among these groups of bacteria were analysed. An increase in TBC, PBC and PLiBC and in the values of free fatty acids (FFA) was tested experimentally in three milk samples in relation to time (analyses were done in 24-hour intervals until 96 hours) and storage temperature of milk samples (4; 6.5 and 10°C). Bacterial contamination of milk was determined by culture methods in accordance with IDF standards, the values of FFA were determined by an extraction-titration method. These mean values were determined in the set of samples (n = 491): PLiBC 659 CFU/ml, PBC 2 932 CFU/ml and TBC 18 932 CFU/ml. A high correlation was proved between values of PBC and PLiBC (r = 0.87; P < 0.001) while the correlation between TBC and PBC (r = 0.65; P < 0.001) and between PLiBC and TBC (r = 0.59; P < 0.001) was on a medium level. The proportional index p_I for PLiBC/PBC was 0.20, for PLiBC/TBC 0.03 and for PBC/TBC 0.16. In seasonal dynamics a statistically significant difference (P < 0.001; P < 0.05) between the increased values of TBC in the summer season was proved compared to the winter and spring season. The differences in the seasonal variation of PBC and PLiBC values were not significant. Experimental investigation of an increase in the values of tested parameters showed that at temperatures of milk sample storage 4 and 6.5°C TBC did not exceed the permissible hygienic value (100 000 CFU/ml) even after 96 hours while at 10°C it amounted to 90 000 CFU/ml after 48 hours and the limit for TBC was exceeded several times after 96 hours. PBC, which is not inhibited by cold storage to such a large extent, did not exceed the hygienic limit value for PBC (50 000 CFU/ml) even after 96 hours when milk samples were stored at 4°C, but at 6.5°C after 72 hours and at 10°C already after 48 hours the values 6 and 20 times higher, respectively, than the hygienic limit were recorded. A similar trend was observed in PLiBC, which exceeded the hazardous limit (43 000 CFU/ml) at 6.5°C after 96 hours and at 10°C already after 48 hours whereas at 4°C the limit value was not exceeded even after 96 hours. The content of FFA also increased in relation to the storage time and temperature of milk samples but in comparison with the increase in the tested groups of microorganisms the increase in FFA showed a higher correlation with storage time compared to storage temperature. A medium correlation was calculated between PLiBC and/or PBC and FFA content (r = 0.52; r = 0.57; P < 0.001).

We want to study the circadian rhythm of dROMs and anti-oxidative power in dairy cattle during dry period and the possible involvement of the circadian organization of rest/activity cycles in the fluctuation of redox state. For this purpose we recorded TLA in five clinically healthy Bruna Italian dairy cattle by means of an actigraphy-based data logger, Actiwatch-Mini^®. Blood samples were collected every 3 hours over a 48-hour period for the assessment of free radicals (dROMs) and the antioxidant power: antioxidant barrier (Oxy-ads) and thiol-antioxidant barrier (SHp). All animals were in the same productive period (dry) and they were housed in the same stable under natural photoperiod and ambient temperature. One-way repeated measure ANOVA was used to determine a statistical significant effect of time on the studied parameters. A trigonometric statistical model was applied to characterize the main rhythmic parameters according to the single cosinor procedure. A significant effect of time on all studied parameters was observed. They showed a diurnal acrophase and different degrees of robustness of rhythms. In conclusion, we can claim that there is a synergism between the dROM circadian rhythm and the circadian rhythm of anti-oxidative power. These rhythms do not have any implication for the issue of causation with the TLA circadian rhythms.

CpG islands (CGIs) are an important group of CpG dinucleotides in the guanine- and cytosine-rich regions as they harbour functionally relevant epigenetic loci for whole genome studies. As a matter of fact, since there has not been a formal comparative analysis of CGIs in domestic even-toed ungulate genomes, this study was performed to serve this comparison. The Hidden Markov Model was used to detect CGIs in the genomes. The results indicated that the CGIs number and CGI densities had scant variations across genomes. The goat genome had the highest number of CGIs (99 070), whereas the alpaca genome had the highest CGI density (43.39 CGIs/Mb). Significant positive correlations were observed among CGI densities with chromosome pair number, observed CpG/expected CpG, recombination rate, and gene density. When the size of chromosomes increased, the CGI densities decreased and a trend of higher CGI densities in the telomeric regions was observed. Only 10.96% of CGIs were methylated underscoring this postulation that the majority of CGIs remains to be unmethylated. The highest amount of the methylated CGIs was observed in the introns, intergenic, and coding (CDS) regions and the lowest amount of the methylated CGIs was observed in the promoter regions, implying that the DNA methylation of CGIs may control gene expression at the genome level. Detected differences between even-toed ungulate and other vertebrate genomes showed that CGI densities varied greatly among the genomes. These findings would contribute to better understanding the even-toed ungulate (epi) genomes, the role of CGIs in epigenomic functions and molecular evolution.

Breeding of hybrids between wild boars and domestic pigs is in the consumer interest because of the need to ensure food security and diversification via widening the genetic basis of animals reared for meat. To expand the knowledge about their nutritional requirements, this study aimed to investigate hindgut fermentation in these animals. Caecal and colon cultures were incubated for 12 h in vitro with or without wheat bran as a supplementary substrate. Short-chain fatty acids, ammonia, methane, and total gas production were determined. The total concentrations of short-chain fatty acids in unincubated caecal and colon samples were 93.1 and 115 mmol/kg, respectively. The short-chain fatty acid profile in fresh hindgut contents was characterized by a high molar proportion of acetate (74.8-75.0 mol%), followed by propionate (18.2-18.5 mol%) and butyrate (5.4-5.5 mol%). The presence of wheat bran lowered acetate and increased butyrate, propionate, and valerate molar proportions. The ammonia level remained low (1.3-2.43 mmol/kg) regardless of the addition of the substrate. The relatively low pH and ammonia concentration in wild boar/pig hybrids may be caused by the low level of crude protein in diet of these animals. The rate of methanogenesis increased during the fermentation simultaneously with an increase in the production of gases after wheat bran addition. Methane production in the caecal and colon samples incubated with the substrate reached 15.6 and 16.1 mmol/kg, respectively. The hindgut fermentation pattern in wild boar/pig hybrids generally resembled that described earlier in domestic pigs, although some observed dissimilarities may be caused by distinct microbial activity.

This study examined the variability of reproductive and productive traits in Suffolk sheep (a commercial flock, n = 316 ewes) with regard to the dams' age or the nutritional status of sheep at mating under a year-round outdoor management. Data were collected across a 3-year monitoring period (totally 655 observations). The fixed effects of dam's age (dams grouped as: 2, 3, 4, 5, 6 years and older), ewe's live weight (LW; ewes grouped as: < 72 kg; 72-83 kg; > 83 kg), and backfat thickness at mating (BT; ewes grouped as: < 7.9 mm; 7.9-10.5 mm; > 10.5 mm) were evaluated. The dam's age influenced reproductive and productive traits such that 2- and 6-year and older ewes reached the lowest values. Ewes with LW > 83 kg had significantly higher lambing rate (11.8%) compared to those with LW < 72 kg. The group of ewes with LW < 72 kg gave birth to a significantly lower number of live lambs in litter (-8.9%) in comparison with LW < 83 kg group. An increase (9.9%; P < 0.01) of total litter weight at birth or an increase (12.5%; P < 0.05) of total litter weight at 100 days of age were detected in LW > 83 kg group compared to LW < 72 kg group. BT > 10.5 mm ewes had by 8.9% lower lambing rate (P < 0.05), by 6.8% lower litter size (P < 0.05), by 14.5% lower number of live lambs in litter (P < 0.01), and by 8.6% lower total litter weight at birth compared to BT < 7.9 mm ewes. A significantly lower total litter weight at 100 days of age (-10.8%) and a significantly lower total litter gain from birth to 100 days of age (-11.5%) were detected in BT > 10.5 mm ewes in comparison to BT 7.9-10.5 mm ewes.

Apricot is one of the oldest fruit tree crops in China and it was spread via Armenia to other areas. There are about ten species of apricot (Subg. Armeniaca Mill.) worldwide, among which nine species are native to China. Sharka disease caused by the Plum pox virus (PPV) is widely distributed in the main producing regions of apricot. In this study, linked simple sequence repeats (SSR) primers were used to detect allele variations potentially associated with PPV resistance among Chinese apricot germplasm resources, including 52 accessions belonging to Prunus armeniaca, 7 to Prunus mandshurica, 6 to Prunus sibirica, 4 to Prunus mume, 17 to other species or types. The allelic variation at loci with PPV resistance showed that these SSR markers linked to PPV resistance kept a relatively high level of diversity in Chinese apricot. The special alleles and genotypes only found in South China cultivars might reveal new PPV resistance sources. Some famous local cultivars of Chinese apricot might be considered as candidates for PPV resistance.

This study was conducted in order to determine the antioxidant activities of certain apple varieties. 'Galaxy Gala', 'Scarlet Spur', 'Fuji', 'Pink Lady' and 'Granny Smith' were characterized in this study. The antioxidant activities among the varieties were determined via three different procedures. Antiradical activity figures of the apple varieties were between 0.592 ('Galaxy Gala') and 0.802 ('Scarlet Spur'). Inhibition levels of chelating activity with Fe⁺² varied between 40.20-55.50%; 'Scarlet Spur' and 'Pink Lady' extracts had the highest inhibition with 55.50% and 'Granny Smith' extract had the lowest with the level. Among the extracts showing H₂O₂ clearance effect, Granny Smith (62.54%) and Scarlet Spur (44.67%) extracts had the highest inhibition levels. In this study conducted on apple varieties, total phenolic matter levels were determined in 'Scarlet Spur', 'Pink Lady', 'Fuji', 'Galaxy Gala' and 'Granny Smith'.

The aboveground parameters and the parameters of root plates in uprooted Norway spruce trees (Picea abies [L.] Karst.) were measured in the Hnile Blata locality (the High Tatras Mts.) (waterlogged sites) and in the Zemska locality (Low Tatras Mts.) (well-drained sites). The methods of linear correlation and regression analysis were used to quantify the relationships between the aboveground and belowground parameters. In waterlogged sites, a signifiant correlation (r = 0.60) was found between the stem diameters and the horizontal width of root plate, calculated average width of root plate, theoretical surface of root plate and visible surface of root plate. A medium correlation was found out between the stem diameters, tree height and the vertical radius of root plate. Similarly, a medium correlation was also determined between the tree height, width and length of crown and the horizontal width of root plate, average calculated width of root plate, theoretical surface of root plate and visible surface of root plate in spruce trees growing in waterlogged sites. In well-drained sites, was found out a medium correlation between the stem diameters and the horizontal width of root plate, partial vertical radius of root plate, average calculated width of root plate, theoretical surface of root plate and visible surface of root plate. A somewhat lower correlation was observed between the tree height and the vertical radius of root plate, average calculated width of root plate and theoretical surface of root plate in spruce trees growing in well-drained sites. In both sites, was found out a slight correlation between the aboveground parameters and the thickness of root plates; and no correlation was determined between the crown proportion index and root plate parameters.

Taxocenosis of psocids (Psocoptera) was studied in the territory of the Drahanská vrchovina Hills in the Czech Republic. Representative research plots were selected in forest ecosystems with natural species composition and spatial structure (small-scale strictly protected areas) as well as in forest ecosystems with altered tree species composition and spatial structure. Research was conducted in three altitudinal vegetation zones (AVZ): in 2^nd communities of Fagi-querceta s. lat. (beech-oak forests), 3^rd Querci-fageta s. lat. (oak-beech forests) and 4^th Fageta abietis (beech forests with fir). Research plots are situated at altitudes ranging between 275 and 540 m a.s.l. In the 2013 growing season, totally 3,474 imagoes and 2,532 nymphs of 32 psocid species were collected. Of those, 748 imagoes of 25 psocid species were collected in Fagi-querceta. The occurrence of Caecilius burmeisteri, Caecilius flavidus and Graphopsocus cruciatus was eudominant. 2,194 imagoes of 23 psocid species were found in Querci-fageta, eudominant were there Caecilius flavidus and Caecilius burmeisteri. 532 imagoes of 18 psocid species were found in Fageta abietis, eudominant were there: Caecilius flavidus, Peripsocus subfasciatus and Caecilius burmeisteri. In respect to the species composition, 3^rd AVZ and 4^th AVZ are similar to each other while 2^nd AVZ is less similar.

The aim of the present study was to analyse the impacts of different logging intensities after five years from logging including non-logged, low (3.4 felled stems per hectare), medium (5.2 felled stems per hectare) and high (7.1 felled stems per hectare) treatments on stem density, basal area, canopy cover, and forest biodiversity indices. The study area was located in northern Iran. Data was collected on a set of 120 circular plots with 5 m radius from both non-logged and logging areas. Stem density, basal area, and percentage of canopy cover were measured. Biodiversity study was done by measuring two diversity indices including Simpson's and Shannon-Wiener's, two richness indices including Margalef's and Menhinick's and two evenness indices including Pielou's and Hill's indices. The results indicated that the treatment with the medium logging intensity was found to cause the highest amount of positive effects on stem density, basal area, and biodiversity indices. It is concluded that harvesting intensity should be limited to a medium level (approximately 5 felled trees per hectare) during each logging operation to improve forest biodiversity indices.

The strong market competition forces forest owners to find innovative approaches to forest management, and business models are becoming integral parts of successful innovations and business strategies. This paper deals with the applicability of a business model (as an innovation tool) for small forest owners. The main objectives were to design a business model applicable in the forestry sector and to find the innovative business alternatives for the small-scale forest owner reflecting the local situation (in a case study in the Czech Republic). The extended business model CANVAS was used. The embedded data was evaluated on the software developed at the Savonia University in Finland where business opportunity and competitive advantage were the main evaluation criteria. As a result, a proposed strategy was advised to be followed. The biggest added value of the extended CANVAS model is giving an objective and unbiased evaluation of the situation of small forest owners. The business model design proved a usable and applicable tool to be used in forest management, for the research has shown that the quantitative data should be complemented by qualitative research in order to get the complex view.

The present study has been done to evaluate the impact of pure ash stand and mixed stand with beech on the herb layer biodiversity and soil properties in the forests of Noor city. There is a unique stand of ash in the forests of Noor city and at 1,900-2,100 m a.s.l., which is rarely seen like that in the northern forests of Iran. Shannon-Wiener diversity indices (H'), Simpson index of dominance (D), Margalef richness (R₁) and Pielou's evenness were used to analyse biodiversity. Sampling was also conducted to investigate physical and chemical properties of soil (bulk density, acidity, electrical conductivity, soil moisture, soil lime, nitrogen and organic carbon) in each sample plot and at two depths (10 and 20 cm). The total number of 26 soil samples (13 soil samples at either depth) in pure ash stand and 24 soil samples (12 soil samples at either depth) from this type of stand mixed with beech were taken. The results of plant species biodiversity showed that between the pure ash stand and the stand mixed with beech there is a significant difference at the 99% probability level in Shannon-Wiener diversity, Margalef richness, and Simpson dominance. There is also a significant difference at the 95% probability level between the two stands under study in Pielou's evenness index. The results of soil factors also showed that at the depth of 10-20 cm acidity factor showed a significant difference from its adjacent stand at the 99% probability level. There is also a significant difference at the 99% probability level in acidity (0-10 cm) and soil moisture at the depth of 10-20 cm between the two areas, but there is not any significant difference between the areas under study in electrical conductivity and lime factors at the two depths and also in moisture content at the depth of 0-10 cm. It should be noted that between the stand and soil nitrogen, organic carbon and bulk density parameters at both depths (0-10 and 10-20 cm) a significant difference at the 95% confidence level is shown.

The occurrence of chestnut blight (Cryphonectria parasitica) was studied in 2011-2012 at 13 locations in the main chestnut growing areas of Romania. Infections were detected at four localities. The symptoms and the fungus were detected on European chestnut (four localities) and also on oak trees (two localities). A total of 89 isolates of C. parasitica were isolated and characterised. Based on canker and isolate morphology (culture morphology and the Bavendamm test), both virulent and hypovirulent samples were isolated; hypovirulent isolates were found at only one locality. Two vegetative compatibility types corresponding to EU-12 and EU-2 were identified among isolates. Both mating types were found, with a dominance of MAT-1 in southern Romania and MAT-2 in northern Romania.

Key scale insects that have long been considered as having high economic importance in Tunisia and for which several research studies and pest management programs have been undertaken include the mealybug species Planococcus ficus (Signoret) and Planococcus citri Risso, the soft scale Saissetia oleae (Olivier) and the armoured scale Parlatoria ziziphi (Lucas). The host plants, bio-ecological aspects, auxiliary fauna of each of the aforementioned species as well as the related economic losses and pest management strategies adopted are explored and discussed. Among these species, P. ficus is considered herein as the most economically important in Tunisia. Still, the present contribution constitutes the first review article on key scale insects infesting plants in the South Mediterranean Maghreb area.

The different materials and methods used to develop biopesticides with entomopathogenic nematodes (EPNs) still limit the quality of the final product, reducing field efficacy and complicating application strategies. Therefore, the objective of this review is to identify priority areas to improve the EPN formulation process based on the scientific and technological research developed so far. The results show great progress in the EPN survival time, from 7 days to 180 days, through two types of formulations: water dispersible granules and calcium alginate capsules. Also, EPNs formulated and applied as insect cadavers showed higher efficacy for the pest control than the EPNs applied in an aqueous solution. We consider that the priority areas of research are: automated massive formulation and exploration of new additives with better properties that may lead to increase the infectivity in the field. It is concluded that the study of these aspects requires a systemic approach with greater involvement of the invertebrate physiology and systems modelling disciplines.

Sixty-two endophytic bacteria from the leaves, roots, and stems of healthy Lepidium perfoliatum L. were isolated and characterised. From the results, 89, 87, 90, and 97% isolates could tolerate 12% NaCl, 30% PEG 6000, 50°C and pH 10, respectively. 74% isolates could form a biofilm. Besides, 28 isolates could improve the germination rate of host seeds under different degree of drought stress. These data suggest that the endophyte isolates show considerable resistance to abiotic stress and assist their plant hosts to germinate under drought stress.

The effect of a single chemical treatment against Ostrinia nubilalis (Hbn.) on thrips abundance on maize in south-eastern Poland was evaluated. Two insecticides: Karate Zeon 050 CS, containing lambda-cyhalothrin, and Proteus 110 OD, containing thiacloprid with deltamethrin, were tested. Maize was sprayed in the second ten days of July, during the abundant occurrence of O. nubilalis larvae, which coincided with the population peak of thrips on plants. The tested active substances showed high effectiveness against thrips, but a better effect, reflected in a decrease in thrips abundance, was found for the mixture of thiacloprid with deltamethrin. The tested insecticides significantly reduced the population of thrips for up to 14 days after treatment.

The possibility of reduce the length of poppy plants and their risk of lodging by applying selected plant growth regulators and effects on the plant and yield were studied in field experiments during 2010-2012. Statistically significant reduction was achieved only with ethephon (576 g a.i./ha) in all experimental years. In 2010 reduction for metconazole (60 g a.i./ha) was recorded. In 2012, ethephon at rates of 576 and 288 g a.i./ha prevented significantly poppy lodging. The 576 g a.i./ha rate was phytotoxic and decreased yield. The commonly used 576 g a.i./ha rate diminished heights by 16-20 cm in all experimental years and significantly reduced lodging in 2012, but decreased yields in two of the 3 years.

Prociphilus (Meliarhizophagus) fraxinifolii (Riley, 1879) (Hemiptera: Eriosomatidae) is an alien species in Europe that has been spreading quickly there. This paper presents the origin and current occurrence, classification, description, identification, and biology of this species. It also discusses the harmfulness and threats, especially the impact on host- plants and ecosystem, invasion rate and facilitating factors.

The amount and spatial distribution of plants afflicted with cabbage root maggot (Delia radicum; CRM) and clubroot (Plasmodiophora brassicae) in winter oilseed rape crops were assessed in the Olomouc region (Northern Moravia, Czech Republic) over the course of 2012-2014. A total of 16 commercial rape fields were included in the assessments. Plants with tumours showed a significantly lower (P < 0.001) level of infestation induced by CRM (24% of plants infested) compared to plants without tumours (37% of plants infested). According to a generalised linear mixed model, plants with thicker hypocotyls are predisposed to significantly higher levels (P < 0.001) of root surface damage induced by CRM. The correlation analysis indicates rather weak or intermediate levels of correlation between the two variables (hypocotyls thickness × root surface damage induced by CRM). Both CRM and clubroot symptomatic plants showed a significant tendency for aggregation in rape crops, but not in all cases. Distributions of CRM and clubroot symptomatic plants were either significantly spatially dissociated or not associated in crops. Ovipositing D. radicum females showed some tendency to avoid zones with higher number of plants infected by P. brassicae. Distributions of CRM and hypocotyl thickness levels were significantly spatially associated in crops in several cases.