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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.

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 efficacy of a brief exposure (1, 7, and 10 days) to a nitrogen-controlled atmosphere (N-CA) for major storagepests in a field validation study in the Czech Republic is reported. The main goal was to estimate how quickly themobile adult stages of six species of storage beetles (Oryzaephilus surinamensis, Cryptolestes ferrugineus, Triboliumconfusum, Tribolium castaneum, Sitophilus granarius, and Sitophilus oryzae) are killed after introduction of theinfested commodity to prevent their further spread to the surrounding storage bins. The trials were conducted in ametal bin containing 25 t of seeds using the system of continual top-down nitrogen filling to replace the oxygen. Thecomposition of N-CA in the silo was measured continually. The target N-CA concentration (i.e., ≤ 1% O₂ and 99% N₂)was reached at the bottom of the silo after 12 h of the purging phase of nitrogen silo filling. A one-day exposure toN-CA corresponds to top-down filling, which initially gives higher concentrations of N2 in the upper than in the lowerpart of the silo: low efficacy was reached at the silo bottom (0-33.3%), while higher efficacy (16.7-100%) was reachedat the top of the silo bin. The mortality variation at both locations was species dependent: the most sensitive was O.surinamensis, and the least sensitive were S. granarius and S. oryzae. Seven days of N-CA exposure led to 100% mortalityof all tested species except for S. granarius (96.7% mortality at the bottom), while 10 days of N-CA exposure ledto 100% mortality of all adults located at both the bottom and the top of the silo. This experiment showed that oneday of exposure to N-CA caused significant mortality to reduce the spread of insects from the top of the silo but notfrom the silo bottom, and 10 days of exposure completely prevent the adult mobile pest stages of all tested speciesfrom spreading from the treated silo and causing cross-infestation in the storage facility.

Severe symptoms of root rot on sugar beet have been observed in Poland and Germany since 2001. The symptom classification suggested girth scab as it was mistakenly classified on the basis of current classification, e.g. in LIZ. However, the cause of the disease was Aphanomyces cochlioides infection, not Streptomyces spp. According to these findings we cannot call the symptoms caused by A. cochlioides as 'girth scab'. The typical scab (girth scab) symptoms can be promoted by A. cochlioides infections. In many cases, A. cochlioides developed at the beginning of the season, during the seedling stage. Its further development was due to rainfall and was not routinely recognised in disease-changed tissues if in the middle of the summer the rainfall level was reduced. According to the described findings, renewed description and differentiation of the girth scab symptoms caused by Streptomyces spp. and root rot caused by A. cochlioides on sugar beet roots are suggested. Typical symptoms of the disease caused by A. cochlioides occur mainly on the upper part of the root but can also occur on its lower part, if weather conditions are favourable for the pathogen. The coexistence of A. cochlioides and Pythium spp. in the same niches is also possible. Currently the illustrations showing these symptoms are included in the 'girth scab' descriptions.

Field experiments were conducted at two locations in 2014-2015 and 2015-2016 to investigate the weed suppressive ability of cover crop mulches in sugar beets. Three cover crops and two cover crop mixtures were tested in all four experiments. Weed densities ranged from 2 up to 210 plants/m² in Chenopodium album L. and Stellaria media (L.) Vill. as predominant species. Sinapis alba grew significantly faster than Vicia sativa, Raphanus sativus var. niger, and both cover crop mixtures. Sinapis alba, Vicia sativa, Raphanus sativus var. niger reduced weed density by 57, 22, and 15% across all locations, respectively. A mixture of seven different cover crops reduced weed emergence by 64% compared to the control plot without cover crop mulch. Early sugar beet growth was enhanced by all mulch treatments in 2015 and decelerated in 2016.

Sixty-five Czech Meligethes populations were tested against lambda-cyhalothrin and chlorpyrifos-ethyl in 2014. In 2015, totally sixty Meligethes populations, some of which sampled also in Slovakia, were tested against the two insecticides. Adult vial tests by IRAC (Insecticide Resistance Action Committee) were used for testing (No. 011 v. 3 for lambda-cyhalothrin and No. 025 for chlorpyrifos-ethyl). For each of the tested populations the LC₅₀, LC₉₀, and in 2015 also LC₉₅ values were determined for both these insecticides. Correlation analyses were made with transformed (log10 transformation) LC values. No significant correlation was recorded between the LC₅₀ values. Contrary to that, significant (P < 0.05) negative (r values for negative) correlations were recorded between the LC₉₀ and LC₉₅ values. Pyrethroid resistance in pollen beetle populations should indicate their slightly higher susceptibility to chlorpyrifos-ethyl.

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 reaction of IR 50, TRY 3, and IR 36 cultivars of rice to R. solani challenge, the causal agent of sheath blight, and its toxic metabolite was studied. Differential response of these cultivars to the pathogen and/or toxin inoculation was observed in detached leaf sheaths and greenhouse-grown plants. The observations were based on disease scoring, electrolyte leakage, and also microscopic views of infection cushions. The Osmyb4 gene expression was studied in the tissues from all these experiments and a correlation between the level of expression and disease response of the varieties was found at least in some experiments. The mechanisms regulated by Osmyb4 might have a lower but significant contribution to the tolerance of rice cultivars to sheath blight.

Experiments on the preying capability of different stages of larvae of coccinellid and syrphid flies on the mustard aphid, Lipaphis erysimi (Kalt.), were conducted in a laboratory during the winter cropping seasons of 2009-2010 and 2010-2011. Results revealed that grubs of the Coccinella septempunctata Linn. preyed the highest number of mustard aphids (average 61.42 aphids/day) followed by Syrphus confrater Wied (34.81 aphids/day), Syrphus balteatus Deg. (32.26 aphids/day) and Ischiodon scutellaris Fab. (27.76 aphids/day) during their larval span. Among the larval stages of the coccinellid and syrphid predators, it was also analysed that the last juvenile stage of the predators was proved the mightiest devourer against the aphid L. erysimi. These predators could be used effectively for the management of L. erysimi on rapeseed-mustard crop.

The efficacy of superficial tillage as a sustainable tool to reduce the emergence of Digitaria sanguinalis, Setaria viridis, and Sorghum halepense was evaluated with field experiments. Seeds were buried at 1, 2, 5, and 10 cm of depth to simulate seed vertical distribution caused by autumn superficial tillage. Seedling emergence was monitored weekly for two years after sowing. The highest emergence was obtained in the first year after sowing and from 1 and 2 cm. Sorghum halepense was only slightly affected by seed burial, with 15% of emergence from 10 cm of depth, while D. sanguinalis was strongly affected, with 4% of emergence from 5 cm. The efficacy of superficial tillage as control tool could vary according to local weed flora.

We tested the suitability of Landsat images to track defoliation by insect herbivory with focus on the oak leaf roller, Tortrix viridana (Lep.: Tortricidae). Landsat images from the period before (2002) and after the T. viridana infestation (2007, 2014) were compared in oak forests of Zagros in western Iran. The Normalised Difference Vegetation Index (NDVI) was calculated for the test area from Landsat 5, 7, and 8 images. Because the red and near-infrared spectral bands of Landsat 8 OLI sensors are different from the other two, a model for the calibration of Landsat OLI NDVI was developed. The proposed model with a correlation coefficient of 0.928 and root mean square error of 0.05 turned out to be applicable and the NDVI decreased significantly during the observation period. Taking into account the protection status of the area and small fluctuations in temperature, the decrease in NDVI could be attributed to T. viridana damage.

Winter oilseed rape is the second most frequently grown crop in the Czech Republic. Clubroot, caused by Plasmodiophora brassicae (Wor.), was previously a problem in production of vegetable. The disease has been spreading on winter rape (Brassica napus L.) over the past four years. Infected stands were reported throughout the country in autumn 2011. The pathogen is probably widely spread in the whole country, its incidence depends on suitable weather conditions. Every field with clubroot is considered as contaminated for many years. The amounts of inoculum and its distribution are not sufficient yet, but this is just the initial stage of colonisation. There is a similar situation resembling experiences from other countries (Canada, Germany) where clubroot has gradually expanded in the last 15 years.

In 2015, we recorded the first attack of the great spruce bark beetle, Dendroctonus micans (Kugelann) (Coleoptera: Curculionidae, Scolytinae) on non-native Picea orientalis (L.) and Picea pungens (Engelmann) in Slovakia. To our knowledge, the occurrence of D. micans on P. orientalis in Central Europe has not been described yet. We found that D. micans preferred P. orientalis over P. pungens and other coniferous trees in urban areas. In laboratory conditions, 352 adults of D. micans emerged and only 1 predator, Rhizophagus grandis (Gyllenhal) (Coleoptera: Monotomidae), was recorded. D. micans has a potential to become a serious pest of P. orientalis and P. pungens in urban, and in air-polluted areas.

Damage by the cottony cushion scale Icerya purchasi (Hemiptera: Coccoidea: Monophlebidae: Iceryini) was found on Rosmarinus officinalis at the locality Suchohrad in Slovakia. Icerya purchasi is a cosmopolitan plant pest of warmer climates. In Central Europe it is a pest of glasshouses. It is the first observation of the cottony cushion scale (at least short-term) occurrence in the outdoor conditions in Slovakia.

We ranked the most frequently used pre-emergent herbicides in sunflower (Helianthus annuus) according to their efficacy and selectivity under different soil moisture conditions within 2008-2011. The efficacy of oxyfluorfen, aclonifen, acetochlor, dimethenamid, and propisochlor on the majority of weeds (Chenopodium album, Echinochloa crus-galli, Amaranthus retroflexus, Mercurialis annua,and Solanum physalifolium) was only slightly affected by the soil moisture and these herbicides can be used in arid and semiarid regions. The efficacy of linuron, prosulfocarb, and pethoxamid was strongly affected by soil moisture and was insufficient under dry conditions. The majority of herbicides showed good selectivity for sunflower. Crop injury rate of 5-15% was recorded after application of flurochloridone and acetochlor. For flurochloridone, the phytotoxicity increased due to irrigation after herbicide application. The highest sunflower injury rate (27-35%) was recorded after application of oxyfluorfen.

The susceptibility of field and laboratory strains against all instars larvae of S. littoralis to spinosad pesticide after a 24- and 48-h exposure and under laboratory conditions was investigated. As a result against 1^st instar larvae, the LC₅₀ values after 24 h were 12 and 0.275 µg/ml for laboratory and field strain, respectively. In addition, the resistance ratio (RR) of 1^st instar was 43.64-fold. In this interim, the 48 h LC₅₀ values were 8.7 and 0.18 µg/ml for laboratory and field strain, respectively and the RR was 48.33-fold, which revealed the field strain was more susceptible to spinosad than the laboratory strain. Distinctly similar trend was shown for later instar larvae stages. For instance, in 6^th instar larvae, the LC₅₀ values after a 24-h exposure to spinosad were 1100 and 105 µg/ml for the laboratory and field strain, respectively, and the RR value was 10.48-fold. Furthermore, after a 48-h exposure, the LC₅₀ values for laboratory and field strains were 500 and 42 µg/ml, respectively, with RR value being 11.90-fold. On the other hand, according to relative tolerance values, the 6^th instar larvae were the most tolerant instar of all the instars tested. The susceptibility of 6^th, 5^th, and 4^th instar larvae was comparable and significantly lower than that of 3^rd, 2^nd, and 1^st instar larvae. However, the 1^st instar was the least tolerant. The results implied that spinosad may play a potential role in the control of S. littoralis and, therefore, it is considered a promising tool in integrated pest management program to control Cotton leafworm which is becoming resistant to conventional pesticides in Egypt.

To determine stem rust resistance genes of wheat varieties in Yunnan province, 11 Chinese strains of Puccinia graminis f.sp. tritici with different virulence and 1 artificial mutant strain were used in 110 wheat varieties. The results indicated that among the 45 Sr genes, Sr31, Sr5, SrTmp, Sr30, Sr36, Sr8a, Sr11, Sr24, Sr29, Sr34, Sr9e, Sr26, Sr38, Sr47, and SrTt3 were characterised in 55 wheat varieties singly or in combination. Sr5, Sr31, SrTmp, Sr36, and Sr30 were contained in 17, 16, 5, 5, and 3 cultivars, respectively. Six cultivars contained Sr24 and/or Sr34. Three plant materials likely contained one or more of Sr8a, Sr11, Sr34, and Sr23 genes as well as other unknown genes. The 16 immune or highly resistant varieties contained one or more of Sr9e, Sr26, Sr38, Sr47, SrTt3, and other unknown resistance genes. The reaction types on 22 of the tested cultivars were different from those on Sr genes tested, and their resistance genes could not be analysed. Additionally, 17 varieties were susceptible to all the tested strains, having no postulation value. Our study provides a basis for improved breeding of stem rust resistant wheat in China.

In the last twenty years, stone fruit production in Slovenia has considerably decreased. Acreage with peaches and nectarines has been significantly reduced. Orchard renewal has decreased for various reasons; among them, the frequent occurrence of various diseases is the most significant. These diseases make the economic feasibility of stone fruit production difficult if not impossible. This review addresses the most important stone fruit diseases in Slovenia: European stone fruit yellows, sharka, bacterial leaf spot, bacterioses caused by Pseudomonas spp., perennial canker, and Fusicoccum canker. Additionally, this review focuses on the possibilities of reducing the damage caused by these diseases.

Maximum aphid numbers on wheat are positively related to the length of the period elapsed from immigration to the population peak. We predicted that maximum abundances on late maturing cultivars would be greater than on early ones. This was tested using 8 spring wheat cultivars that differed in the length of time to senescence. In a 4-year experiment, numbers of aphids were checked at weekly intervals. Maximum abundances on late-maturing cultivars were significantly greater than those on early cultivars. However, the length of the vegetation period affected maximum abundances less than did the annual variation in aphid abundance. Genetic disposition for early ripening thus tends to decrease aphid numbers, but manipulation of this character is unlikely to become an important source of aphid resistance.

The biochemical properties of proteases from the digestive system of the fig tree skeletonizer moth, Choreutis nemorana, were determined. Gut extracts of C. nemorana larvae were analysed using different specific peptide substrates and proteinase inhibitors. The optimal pH and temperature for proteolytic activities using azocasein as substrate were obtained as pH 11 and 45°C, respectively. In the case of N-benzoyl-l-arg-p-nitroanilide as substrate, the enzyme showed the maximum tryptic activity at pH 11. The kinetic parameters of trypsin-like proteases indicated that the K_m and V_max values of trypsin in the gut of C. nemorana were 0.157 ± 0.006mM and 0.188 ± 0.005 µmol/min/mgprotein. Using specific proteolytic inhibitors, the inhibitors including phenyl methane sulfonyl fluoride, N-p-tosyl-l-lys chloromethyl ketone and ethylene diamine tetraacetic acid showed the greatest inhibitory effect on total proteolytic activity. These results indicated that serine proteinases accounted for the major proteases in the gut of C. nemorana. Inhibition assays and zymogram analysis showed that only small amounts of cysteine proteases are present in the digestive system of C. nemorana.

Genetic variation of striped stem borer Chilo suppressalis populations in Guilan and Mazandaran provinces in Iran was studied in 2010 by means of RAPD markers. Collected 45 samples from 19 locations (representing 17 counties in Guilan province and 2 counties in Mazandaran province) were classified into four groups of populations: three population groups corresponding to the west, centre, and east of Guilan and one population group from the west of Mazandaran. RAPD PCR analysis showed that Chilo suppressalis populations in Mazandaran are genetically different from the Guilan populations while the western populations of Guilan are genetically separated from the two other populations. The central and the eastern populations of Guilan exhibit some similarities with those of Mazandaran and the similarities are more obvious between the eastern populations of Guilan and the western population of Mazandaran. The population from the centre of Guilan showed the highest level of intra-population genetic variation possibly due to wider rice cultivated area and/or due to higher sample size. The results showed a high level of genetic variation in Chilo suppressalis populations in the two provinces in Iran. In spite of the model species is a widely distributed pest, the study indicated that the samples originated in populations with a different genetic make-up.

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.

Field validation of spot-fumigation with phosphine (PH₃) applied by a subcontracted pest-control company in a farm grain store infested by pests was conducted. Inside and outside of the fumigated grain spot, containers with adults of 5 species of coleopteran stored-product pests were regularly spaced. The beetle pests were the internally feeding Sitophilus granarius and Rhyzopertha dominica, and the externally feeding Tribolium castaneum, Oryzaephilus surinamensis, and Cryptolestes ferrugineus. A 100% mortality of all pest species inside the fumigated spot under the sheet used for the application was stated. The efficacy (maximal) sharply declined with the increasing distance from the fumigated spot: 50% mortality was observed at 5 m from the spot, 38% mortality at 10 m, and a mortality of 23% was observed at 15 m. Mortality was different among the species, and the most sensitive was O. surinamensis, whereas the most tolerant were S. granarius, R. dominica, and T. castaneum. Although an efficient fumigation within the spot was found, the efficacy was low in the grains surrounding the spot. The practical implications of the findings are discussed.

The presence of seed-borne viruses in winter squash landraces in the Black Sea region of Turkey were detected. The seed samples of landraces were tested by ELISA for Cucumber mosaic virus (CMV), Zucchini yellow mosaic virus (ZYMV), Squash mosaic virus (SqMV), Tobacco ring spot virus (TRSV), and Cucumber green mottle mosaic virus (CGMMV). Based on the ELISA results, 11.3% of the samples were infected with the viruses; ELISA, CMV was found at the rate of 5.1% in the winter squash samples, while incidence of ZYMV was determined as 6.2%. Moreover, none of the plants germinated from seeds were found to be infected with SqMV, TRSV, and CGMMV. This is for the first time that seed-borne viruses of winter squash landraces have been identified in the Black Sea region of Turkey.

Seedlings of Trifolium pratense L. cultivars were mechanically inoculated with Czech isolates of Alfalfa mosaic virus (AMV), Clover yellow mosaic virus (ClYMV), Clover yellow vein virus (ClYVV), Red clover mottle virus (RCMV), White clover mosaic virus (WClMV), and a newly discovered member of the Cytorhabdovirus genus. WClMV infected 75.4% of clover seedlings; cv. Rezista was the most susceptible (93.3%), while cv. Fresko was the least susceptible (58.3%). RCMV infected 59.6% of plants; the most susceptible was cv. Tempus (77.6%), the least susceptible cv. Sprint (38.3%). While WClMV infected a higher number of seedlings, RCMV revealed more severe symptoms on affected plants. On the basis of ELISA and RT-PCR results, no cultivar was susceptible to mechanical inoculation with ClYMV and cytorhabdovirus. Moreover, cvs Fresko and Sprint were not susceptible to ClYVV and AMV, respectively.

Effect in reducing maize plant height using growth regulators ethephon, chlormequat chloride (CCC), CCC + ethephon, and mepiquat chloride + prohexadione-Ca was studied in field experiments during 2010 and 2011. It was found that maize plant height could be reduced by as much as 125 cm (49% of control) using a double application of ethephon (576 g a.i./ha) at growth stages BBCH 18-19 and BBCH 34-36. The other growth regulators displayed weak or no influence. An optimum level of shortening was achieved using ethephon (576 g a.i./ha) at BBCH 34-36 (reducing plant height by 40-90 cm), but it is necessary to count upon yield loss of 0.5-0.6 t/ha.

Scaphoideus titanus Ball, the main vector of Flavescence dorée phytoplasma, was monitored in Slovakia during 2013 and 2014. The species was present in the vineyards of eastern Slovakia but it was rarely found in the south of central part of the country. It was also found at many locations of western Slovakia but not in the southeast of western Slovakia. Higher abundance of S. titanus was detected in the vineyards with biological control. Varietal preference of the leafhopper was not confirmed. The first nymphs were found on June 5 and the last nymphs on July 17, adults occurred from the end of June to the end of September. There is one generation of S. titanus per year in Slovakia.

Seedlings of ten Lr near-isogenic lines (NIL) and four wheat lines with enhanced resistance to Puccinia triticina were treated with overdosed neonicotinoid insecticides. The enzyme of Lr 20 gene accelerated thiacloprid degradation while Lr 29 gene accelerated thiamethoxam degradation according to NILs upper plant parts lengths reduction by 6% or 10% six days after the last of three daily treatments. Lr 27 and Lr 33 effects were intermediate on thiamethoxam but only in the driest conditions. Among other NILs the growth was increased 1-5% by N faster release of S or Cl. The accumulation of Lr 20 and Lr 9 facilitated treatment in the late grain filling period when the amount of their circled residues in seed was permissible. In semiarid regions, when thiamethoxam was applied before June, respecting the adequate leaf area duration of prevalent varieties, interaction with Lr 29 could be also practical through simultaneous release of fungi reducing elements.

Peach fruit fly, Bactrocera zonata (Saunders) (Diptera: Tephritidae), has been a serious pest in the last decade attacking a wide range of fruits in Egypt. The toxicity of Malathion, Diazinon, Methoxyfenozide, and Lufenuron to adult males and females of Bactrocera zonata was studied under laboratory conditions. Diazinon was the most toxic among the tested compounds followed by Malathion, Lufenuron and Methoxyfenozide to Bactrocera zonata at 24 h post treatment, the respective LC₅₀ values were 0.20 ppm, 0.48ppm, 8.97ppm, and 9.73ppm for males and 0.26 ppm, 0.91ppm, 11.26ppm, and 14.12ppm for females. At 48 h post treatment Diazinon was the most toxic followed by Malathion, Methoxyfenozide and Lufenuron to Bactrocera zonata, LC₅₀ values were 0.09ppm, 0.34ppm, 1.60ppm, and 1.88 ppm for males and 0.14 ppm, 0.44ppm, 1.68ppm and 2.17 ppm for females. At 72 h post treatment Diazinon was the most toxic followed by Malathion, Lufenuron and Methoxyfenozide to Bactrocera zonata, LC₅₀ values were 0.02 ppm, 0.13ppm, 0.22ppm and 0.51ppm for males and 0.07 ppm, 0.16ppm, 0.55 ppm and 0.62 ppm for females. It is observed that LC₅₀ values for treated adult females increased more than in the treated adult males at 24 h, 48 h, and 72 h post treatment. It means that the adult males were more susceptible to the tested insecticides than the adult females.