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The preponderance of susceptible sour orange (Citrus aurantium L.) rootstock has facilitated the spread of Citrus tristeza virus (CTV) in Trinidad and Tobago. CTV is transmitted by the brown citrus aphid Toxoptera citricida (Kirkaldy), which establishes large colonies on new flushes of citrus plants. As the colonies become highly populated, winged (alate) aphids are produced which can migrate to uninfected neighbouring citrus trees and hence transmit CTV. In the present study different concentrations of the entomopathogenic fungus Verticillium lecanii (Zimm) Viegas in water-based formulations were applied to T. citricida and the pathogenic effects were analysed. Bioassays were also conducted on the major parasitoid Lysiphlebus testaceipes Cresson to test the pathogenic effects of V. lecanii on mortality and the percent emergence from mummies. The LC₅₀ values for T. citricida and L. testaceipes were 2.26 × 10¹⁰ spores/ml and 1.09 × 10⁹ spores/ml, respectively. Statistical analyses indicated that there was no significant difference between the two LC₅₀ values. At the highest concentration (1.49 × 10⁹ spores/ml) percent mortality peaked at 78.9% after 12 days and 1.95 × 10⁹ spores/ml, mortality of L. testaceipes reached 95.1% after 6 days. Emergence of L. testaceipes at the highest concentration of 1.95 × 10⁹ spores/ml was 57.8%.

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.

Alfalfa (Medicago sativa L.) is concluded to be the principal reservoir of Pea streak virus (PeSV, genus Carlavirus) which induces necrotic streaking symptoms in pea. This virus is prevalent in pea growing areas in the USA, but in Europe it was recorded only once almost 60 years ago. Recently, filamentous virus particles 600-700 nm long have been observed in examined plant sap of alfalfa with leaf malformation, local necrotic lesions and yellow spots on leaves. Four kilo base pairs nucleotide sequence of PeSV including partial replicase gene, triple gene block, and capsid protein (CP) gene has been determined. On the nucleotide level, the sequence of the CP has about 80% identity with the North American isolates of PeSV, however, on the amino acid level the sequence has more than 94% identity. This is the first sequence-based proof of PeSV presence in Europe.

Sugar beet yield loss was predicted from early observations of weed density, relative weed cover, and weed biomass using non-linear regression models. Six field experiments were conducted in Germany and in the Russian Federation in 2012, 2013 and 2014. Average weed densities varied from 20 to 131 with typical weed species compositions for sugar beet fields at both locations. Sugar beet yielded higher in Germany and relative yield losses were lower than in Russia. Data of weed density, relative weed cover, weed biomass and relative yield loss fitted well to the non-linear regression models. Competitive weed species such as Chenopodium album and Amaranthus retroflexus caused more than 80% yield loss. Relative weed cover regression models provided more accurate predictions of sugar beet yield losses than weed biomass and weed density.

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.

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.

Natural parasitism of the European corn borer eggs (Hübner) by Trichogramma spp. (Hymenoptera, Trichogrammatidae) was assessed in sweet corn field in north-west Serbia, region Vojvodina at the localities of Ruski Krstur, from 2004 till 2007. The rate of egg parasitism in 2004 varied from 35.89% to 73.58%. The parasitism in 2005 was lower than in 2004. On four different sampling dates in 2005 parasitism varied from 28.48% to 57.05% and averaged 39.4%. In 2006 parasitism fluctuated between 9.31 and 62.9%, averaging 32.15%. In 2007 parasitism varied from 36.8% to 54.54% and averaged 43.48%. The egg parasitoid species was identified as Trichogramma evanescens (Westwood). The study showed that this natural enemy occurred constantly in sweet corn fields but its number greatly fluctuated from year to year.

Ditylenchus weischeri was recently reported in the provinces of Manitoba and Saskatchewan, Canada. Populations of D. weischeri from creeping thistle (Cirsium arvense L.) in Manitoba and D. dipsaci from garlic (Allium cepa L.) in Ontario were examined for their potential to grow on callused carrot (Daucus carota subsp. sativus) disks, alfalfa (Medi- cago sativa L.) and creeping thistle callus tissues, and pure cultures of eight fungal species, Botrytis cinerea, Fusarium solani, Rhizoctonia solani, Verticillium dahliae, Sclerotinia sclerotiorum, Cladosporium cucumerinum, Colletotrichum gloeosporioides, and Chaetomium spp. Ditylenchus weischeri and D. dipsaci could not be reared on any of the fungal isolates nor in the callus tissues of creeping thistle. In contrast to D. weischeri, D. dipsaci was successfully reared on the alfalfa callus tissue. On the callused carrot disks, with no media, an increase of 54 and 244 times the initial density of 80 nematodes was obtained for D. weischeri and D. dipsaci, respectively. Monoxenic rearing was performed using callused carrot disks to provide sufficient D. weischeri inoculum for the microplot study. The effect of D. weischeri on yellow pea varieties Agassiz and Bronco was determined in a microplot trial using initial densities of 0, 100, 200, 400, 800, 1600, and 3200 nematodes/plant. While it had no impact on pea grain yield, D. weischeri slightly reduced plant height, aboveground biomass, and pod length at the population densities of 1600 and 3200 nematodes/plant. The final population densities at harvest were not significantly different from the initial densities indicating the pea varieties were poor hosts to D. weischeri. The results of the present study indicate that D. weischeri is unlikely to be a pest of yellow pea for weather conditions of the Canadian Prairies.

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.

The occurrence of both diseases was evaluated for four years in a selected orchard where 22 different apple progenies, totalling 699 seedlings were planted. During this period, no chemical protection against the diseases was applied in the orchard, and the incidence of the diseases was rated using a 9-point scale (from 9 = not infected to 1 = very highly infected). For the finalisation of the results, each seedling was characterised by the highest rate of infection from all four years of the evaluation. The lowest mean level of mildew infection equal to 7.47 was observed in the progeny of Resista × McIntosh Wijcik. Concerning the scab, the best was the progeny of Resista × Karmína having a rating equal to 8.27. The highest level of segregation of seedlings having joint resistance to both diseases was found out in the progenies obtained by crossings of HL665 × HL782 and Resista × HL447.

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.

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.

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.

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.

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 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.

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.

Tomato yellow leaf curl disease (TYLCD) is one of the most devastating plant diseases in the world. As a result of its continuing rapid spread, it now afflicts more than 30 tomato growing countries in the Mediterranean basin, southern Asia, Africa, and South, Central and North America. The disease is caused by a group of viral species of the genus Begomovirus, family Geminiviridae (geminiviruses), referred to as Tomato yellow leaf curl virus (TYLCV). These are transmitted by an insect vector, the whitefly Bemisia tabaci, classified in the family Aleyrodidae. The genome of TYLCV generally consists of a single circular single-stranded (ss) DNA molecule, with only one exception in which two components were identified. It encodes six open reading frames, only one of which codes for the coat protein (CP) that represents a building block of the viral particle. TYLCV, like all other members of the Geminiviridae, has geminate particles, apparently consisting of two incomplete T = 1 icosahedra joined together to produce a structure with 22 pentameric capsomers and 110 identical CP subunits. Close to 50 years of intensive research into TYLCV epidemics has been conducted to find solutions to the severe problem caused by this virus. To date, breeding for resistance appears to be the best approach to controlling this disease, although only partially resistant varieties are commercially available. Since the virus consists of a ssDNA that replicates in the host-cell nucleus, the molecular mechanisms involved in its nuclear import have been the focus of our studies in recent years and results, as well as prospects, are discussed in this review. In addition, we describe our recent finding of a suppressor of gene silencing encoded by one of the TYLCV-Isr genes. This paper provides an overview of the most outstanding achievements in TYLCV research that may lead to more effective control strategies.

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.

The survival and infectivity of infective juveniles of the entomopathogenic nematode Steinernema feltiae (Rhabditida: Steinernematidae) were determined after being exposed to 8 insecticides (a.i. kinoprene, lufenuron, methomyl, metoxyfenozide, oxamyl, piperonyl-butoxide, pyriproxyfen, tebufenozide), 7 acaricides (a.i. azocyclotin, clofentezin, diafenthiuron, etoxazole, fenbutatinoxide, fenpyroximate, tebufenpyrad) and 4 fungicides (a.i. captan, fenhexamid, kresoxim-methyl, nuarimol) under laboratory conditions. S. feltiae was tolerant to all tested insecticides and fungicides, mortality during 72 hours varied from 2.26% to 18.68 % and from 7.04% to 8.86%, respectively. Acaricides with a.i. fenpyroximate and tebufenpyrad considerably influenced the S. feltiae ability to infect larvae of Tenebrio molitor. Tebufenpyrad caused 95% and fenpyroximate 85% reduction in S. feltiae virulence. These results suggest that S. feltiae can be applied in combination with all tested pesticides except the acaricides with a.i. tebufenpyrad and fenpyroximate.

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.