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Virulences to powdery mildew resistances in barley cultivars mostly carrying unknown resistances were determined in 2009 and 2010. Random spore samples of the airborne pathogen populations originating from winter and spring barley fields were obtained by means of a mobile version of a jet spore sampler by travelling across theCzech Republic. In total 301 isolates were studied, 55 differentials carrying mostly unknown resistances were used and 80 pathotypes were found, of which 26 representing 73.1% of isolates were detected in both years. Virulence frequencies showed a wide range from 0% to 100%. Complexity of the 2010 population slightly increased, mostly due to increasing frequencies of virulence to new resistances, whereas the complexity of virulences to resistances in most other differentials decreased. Pathotype 00027 was the most abundant (10.0%). Diversity of the 2010 population considerably increased due to changes in virulence frequencies.

The effects of storage on the lipid composition of three redgram (TTB-7, BRG-1, and ICP-8863) and three greengram (PUSA BISAKI, KDM-1, and CHINA MOONG) varieties were studied. Environment variables such as temperature and relative humidity were recorded during storage period. Moisture content was found to increase along with the percent incidence of storage insects. The incidence of storage moulds and insects was recorded in all the samples; results showed that storage moulds belonged to Aspergillus species and the insect Callosobruchus chinensis infested the stored samples. The total fat, triglycerides, phospholipids, free fatty acids and peroxide value were evaluated in the control and in samples stored for three and six months. Results showed that storage depleted total fat (1.94-1.75 g), triglycerides (1.46-1.07 g), whereas phospholipids (0.06-0.21g), free fatty acids (0.002-0.01 g) and peroxide values (2.14-4.46 meq) increased. The fatty acid content of palmitic (26.03-23.56%), stearic (7.4-5.46%), linoleic (56.2-45.2%) and linolenic acids (6.9-4.7%) decreased, but oleic acid content increased (8.3-21.6%) in all the varieties during storage.

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%.

Communities of xylotrophic fungi were studied in wood of Pinus mugo of different qualities: (i) living stems, (ii) cut stumps, (iii) burned snags, (iv) cut burned stumps, (v) stems recently killed by root rot, and (vi) old snags of root rot-killed trees. A total of 277 isolates representing 58 fungal taxa were obtained from 300 wood samples (50 samples per each substrate category). Results of the present study suggested that following different disturbances (tree felling, forest fire or root rot), fungal communities likely evolve in different directions: depending on its origin (cut, burned or killed by the disease), dead wood might be inhabited by principally different microbial assemblages, and that fire has less effect on community structures than tree felling or root rot.

The fungus Fusarium oxysporum f.sp. pisi (FOP), the pea wilt pathogen, causes appreciable yield losses under favourable environmental conditions in Algeria. Studies on the pathogen variability and distribution of races are essential to identify effective sources of resistance to this disease. In this study, a survey was conducted during the period 2007-2011 in four different agro-climatic zones. Pathogenic variability in 52 isolates of FOP, collected from different pea-growing areas of western Algeria, were evaluated using 7 genotypes as differential hosts. Results indicated that the disease was prevalent in all fields prospected and isolates obtained were assigned to Races 1, 2, 5 or 6 by their pathogenicity. It was found out that Races 1 and 2 were more common in all areas with 61.5 and 19.2%, respectively. This study is the first report of pea Fusarium wilt races distribution in Algeria.

In the period 2009-2011 monitoring of the incidence of phoma stem canker was carried out at selected sites of the Czech Republic (Šumperk and Opava regions in North Moravia). The risk of infection was evaluated by assessing the autumn release of Leptosphaeria spp. ascospores and with the proPlant prediction model. In recent years, the incidence of phoma stem canker has been relatively low and this corresponded with the total count of ascospores released in the autumn period but not with an increased level of infection risk announced by the proPlant model. During the monitored period the ascospore concentration reached maximally 2 ascospores/1 m³ per day. Maximum ascospore release was recorded in 2010 as a result of favourable weather conditions. The first incidence of phoma leaf spot has been observed in mid-October. The higher values of ascospores concentration were recorded in the Opava region, but the total number of the trapped ascospores was more often higher in the Šumperk region.

In experiments using Petri dishes in the laboratory and pots in a greenhouse and climate chamber, we examined the influence of seed treatment on emergence of poppy. Four types of fungi (Alternaria spp., Dendryphion penicillatum, Fusarium spp., and Penicillium spp.) were detected on poppy seeds, with the highest infection rate being 72% for D. penicillatum. Surface disinfection decreased infection rate chiefly in D. penicillatum (by 32%) and in Alternaria spp. (by 16%). Seed treatment increased emergence by 9-10% in laboratory experiments but by only 0-6% in greenhouse experiments. Temperature plays an important role in emergence. In climate chamber experiments at a stable temperature of 12°C, the seed treatments increased emergence by 8-16%.

The efficacy of twelve sodium salts as possible alternatives to synthetic fungicides for the control of onion basal rot caused by Fusarium oxysporum f.sp. cepae was evaluated. In vitro tests showed that there were significant differences between the inhibitory effects of sodium salts on the mycelial growth (P ≤ 0.05) and 2% (w/v) concentrations of sodium metabisulfite and sodium fluoride completely inhibited mycelial growth of the fungus, while other salts did not. Sodium metabisulfite and sodium phosphate monobasic had lower pH values than the other salts. Unlike sodium metabisulfite, sodium phosphate monobasic could not decrease the mycelial growth. The ED₅₀, minimum inhibition concentration (MIC), and minimum fungicidal concentration (MFC) values indicated that sodium metabisulfite was more inhibitory to the fungus compared to sodium fluoride. In soil tests, inhibitory effect of sodium metabisulfite on the fungus was higher than that of sodium fluoride, where sodium metabisulfite completely inhibited mycelial growth at even 0.4% concentration.

The spread pattern of Abutilon theophrasti (velvetleaf) in Austria, the Czech Republic, and Slovakia was analysed based on an exhaustive distribution data set (389 records). Cumulative number of all records showed a continuous increase since its introduction in the 19^th century and > 1970 its spread gained momentum with an exponential increase > 2000. In fields, the species remained rare until 2000. Since then, A. theophrasti has invaded fields much more frequently (78% of all records in fields > 2000) and it was mainly found in sugar beet and maize. Approximately a total of 188 000 ha of the agricultural area are currently at risk of being invaded. Given the on-going spread into fields, the results provide evidence that A. theophrasti may cause serious impacts. Control measures should focus on the prevention of spreading seeds and the establishment of new foci.

In 2014, the journal Plant Protection Science (PPS) completes 50 years of publication (1965-2014). However, its roots extend back to the year 1921. Today, it is an international scientific journal focused on all aspects of plant protection sciences, fully published in English. This occasion offers a fitting opportunity to describe some of the most important historical stages of the journal's development. In our brief historical overview, we summarise the changes in journal title, chief-editors, and editorial policy during the last fifty years, and with an examination of its importance, scope and readership. We present analyses of the journal's development, some for the entire period of 1965-2013, while others are limited to more recent decades. The journal's present place among the world's scientific journals is documented by analyses in the international citation databases, BIOSIS CI, SCOPUS, and WOS. An analysis of three particular citation databases were made in October 2013, while the overall period 1998-2013 was conducted from All Databases/Thomson Reuters in March 2014. PPS is also included in other, important technical-literature databases, including Czech Agricultural and Food Bibliography, AGRIS/FAO database, AGRICOLA, CAB Abstracts, Current Contents, and Zoological Abstracts. Information about all of them is available in Ulrich's WEB database. In the final part of this paper, we summarise some recent achievements of the journal, and discuss some key topics related to its future development.

Most of the vegetable crops are known to depend upon arbuscular mycorrhizal fungal (AM) symbiosis for growth and development, since AM fungi provide nutrients and water in exchange for photosynthates. The influences of AM fungi (Glomus intraradices (G) and Acaulospora laevis (A)) with Trichoderma viride (T) and Pseudomonas fluorescens (P) alone and in combinations on growth, mycorrhization, chlorophyll content, nutrient uptakes, and yield of broccoli plants were studied in pot culture under glasshouse conditions. The obtained results demonstrated that the single inoculation of broccoli plants with T. viride significantly increased the above ground fresh weight, root length, chlorophyll b, head diameter, root phosphorus, and shoot nitrogen in comparison to uninoculated control plants. On the other hand, consortium of G+A+T+P significantly increased plant height, above ground dry weight, root fresh weight, chlorophyll a, head fresh weight, and root nitrogen content. Similarly, G+T showed maximum leaf area, and P alone showed maximum uptake of shoot phosphorus. Whereas when P was supplied along with T, early flowering was recorded. AM fungal colonisation was negligible and only root tips were found infected in G or A treated plants which confirms low dependency of broccoli on AM fungi.

Identification of Meligethes species and their frequencies in adult samples collected at different localities in Central and South Moravia (Czech Republic, 2009-2011) was based on comparisons of morphometric and colour characters and on differences in male and female genitalia. M. aeneus, M. viridescens, M. subaeneus, M. atratus, and M. coracinus were recorded throughout the observation period, while M. nigrescens was recorded just in 2009 and 2011, M. carinulatus and M. maurus in 2010 and 2011. M. aeneus was the most frequent species of all compared samples (2009-2011). Of the accompanying species, M. subaeneus and M. viridescens were markedly more frequent in this study. Considering high resistance of M. aeneus to esteric pyrethroids, it could be helpful to distinguish among the individual Meligethes species occurring in field samples intended for laboratory testing.

In Europe, glyphosate resistant populations have developed in some weed species in perennial crops, including three species of the genus Conyza documented by the International Survey of Herbicide Resistant Weeds. Conyza spp. biology is reviewed in this paper and related to population dynamics and the development of resistant populations. Suboptimal growth stage at application, improper agricultural practices such as overreliance on glyphosate and long-term use of sublethal doses are identified as the most important factors of resistance development. Current control methods in perennial crops including mixtures of glyphosate with other active ingredients are discussed and effective weed management strategies are described to manage the development and spread of glyphosate resistant Conyza spp. in Europe.

A particularly advantageous method of monitoring the flight and calculating the median was used. An example is given in order to understand better the calculation. The medians show that the timing is similar at different latitudes despite local phenological differences. The difference in median flight times between Finland and the Czech Republic was five days on average, but phenological differences are about a month, shown by a comparison of temperatures, the monitoring of buds on spruce, and by the stage of the carrot plants. During the attack by T. apicalis the carrot plants are younger towards north what is unusual in Psyllidae. In extreme north locations as Finland the genetic triggering for flight could not be realised by the strong declining of temperatures. Flight occurs here substantially later as to local photoperiodicity but is the earliest as to phenology, including carrot plants. The very small plants during flight are much more damaged here than the well-developed plants in central Europe.

Spilanthes acmella (Asteraceae) is an endangered ornamental cum medicinal annual herb. This study reports on the effect of two arbuscular mycorrhizal fungi (Glomus mosseae and Acaulospora laevis) applied either alone or in combination on post-transplanting performance of micropropagated S. acmella. Complete plantlets of S. acmella were raised by direct organogenesis from nodal explants on Murashige and Skoog medium supplemented with various cytokinins. S. acmella plantlets responded to all three mycorrhizal treatments in a significantly different way. G. mosseae enhanced the survival rate of S. acmella plantlets to 100%. Plant height, plant spread, number of branches per plant, number of leaves per plant, leaf area, biomass production, and chlorophyll content were significantly higher in AM inoculated plantlets as compared to the uninoculated ones. This clearly demonstrates that AM inoculation improved not only the survival rate of micropropagated plantlets but also their growth and biomass yield.

Field efficacy of neem (Azadirachta indica A. Juss) for managing soil arthropods and Cercospora leaf spots damage to peanut was studied in Ghana from 2008 to 2010. Treatments consisted of neem kernel water extract (NKWE) and neem kernel powder (NKP) applied separately as soil drench at the rates of 10.5 and 21.0 kg/ha at either planting or pegging. Untreated control and chlorpyrifos treatment at pegging were included as checks. Results showed generally that the neem products at the concentrations tested were efficacious and comparable to chlorpyrifos in lowering populations of soil arthropods and severity of leaf spot diseases, leaf defoliation, and scarified and bored pod damage, resulting in increased pod yield in 2008 and 2009.

Monitoring of species spectrum of true bugs (Heteroptera) on apple trees without pest management was conducted in 2010-2011. Two sites were selected - an abandoned orchard and a road alley near the village of Velké Bílovice (Břeclav district, Czech Republic). The capture of true bugs with a fogger device (Pulsfog) on five selected trees in each site was performed. The effective substance deltamethrin at concentration of 0.0025 g/l was applied to the tree crowns. Three collections (28/4, 20/5, and 9/7) in 2010 and two (11/5 and 23/6) in 2011 were done. Out of 55 detected species of true bugs, 43 species occurred in the alley and 29 in the orchard. Thirty-two species were predatory or partly predatory (58.18%), 22 species were phytophagous (40%), and one mycetophagous (1.82%).

Bromus tectorum is a highly invasive annual grass. The fungal pathogen Pyrenophora semeniperda can kill a large fraction of B. tectorum seeds. Outcomes in this pathosystem are often determined by the speed of seed germination. In this paper we extend previous efforts to describe the pathosystem by characterising secondary dormancy acquisition of B. tectorum. In the laboratory approximately 80% of seeds incubated at -1.0 MPa became dormant. In the field, seeds were placed in the seed bank in late autumn, retrieved monthly and dormancy status determined. The field study confirmed the laboratory results; ungerminated seeds became increasingly dormant. Our data suggest that secondary dormancy is much more likely to occur at xeric sites.

In 2007-2012 the first detailed study of P. halstedii distribution and severity was performed in the Czech Republic by monitoring altogether 128 localities. Incidence of the pathogen was recorded at seven localities in south-eastern (Central and South Moravia) and central parts (East and Central Bohemia) of the country; at only four localities the occurrence of sunflower downy mildew symptoms and pathogen sporulation were recorded repeatedly. In all cases the primary infection prevailed, and the severity of infections was rather low. The majority of records were for sunflower experimental fields (e.g. fields of Central Institute for Supervising and Testing in Agriculture. Brno-Chrlice, Czech Republic), one record came from a commercial field and one record from a hobby field. Results of surveys indicate that reservoirs of primary inoculum likely exist in the soil contaminated by P. halstedii oospores in these habitats, but additional transfer by infected seed may be possible. Historical and geographical consequences of recorded infections are discussed, as well as virulence variation in the Czech pathogen populations which is currently in the process of investigation.

The study was focused on the wild pathosystem Lactuca serriola-lettuce downy mildew (Bremia lactucae) and lettuce powdery mildew (Golovinomyces cichoracearum). Observations were focused mainly on recording natural infection of prickly lettuce (Lactuca serriola) by downy and powdery mildews in the East Bohemia and Moravia (the Czech Republic) in the May-September period of 2007-2011, and on the influence of environmental conditions on disease incidence. Only data for July and August were used for the detailed comparisons of occurrence of both pathogens, because intensity of disease in this period was the highest. Data were linked with the average monthly temperature and rainfall rate in the Czech Republic. G. cichoracearum prefers rather low levels of precipitation and temperatures around 20°C, therefore significantly higher incidence of this pathogen was recorded in August 2007. On the other hand in July 2009 and 2010, when the intensities of precipitation were higher, incidence of Bremia lactucae prevailed. In August 2010 and 2011 incidence of both pathogens were more or less similar at all locations. Our observations showed that climatic conditions influence the incidence and prevalence of both pathogens in weedy growing populations of Lactuca serriola.

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.

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.

The antimicrobial activity of six plant extracts from Ocimum basilicum (Sweat Basil), Azadirachta indica (Neem), Eucalyptus chamadulonsis (Eucalyptus), Datura stramonium (Jimsonweed), Nerium oleander (Oleander), and Allium sativum (Garlic) was tested for controlling Alternaria solani in vitro and in vivo. In in vitro study the leaf extracts of D. stramonium, A. indica, and A. sativum at 5% concentration caused the highest reduction of mycelial growth of A. solani (44.4, 43.3 and 42.2%, respectively), while O. basilicum at 1% and 5% concentration and N. oleander at 5% concentration caused the lowest inhibition of mycelial growth of the pathogen. In greenhouse experiments the highest reduction of disease severity was achieved by the extracts of A. sativum at 5% concentration and D. stramonium at 1% and 5% concentration. The greatest reduction of disease severity was achieved by A. sativum at 5% concentration and the smallest reduction was obtained when tomato plants were treated with O. basilicum at 1% and 5% concentration (46.1 and 45.2 %, respectively). D. stramonium and A. sativum at 5% concentration increased the fruit yield by 76.2% and 66.7% compared to the infected control. All treatments with plant extracts significantly reduced the early blight disease as well as increased the yield of tomato compared to the infected control under field conditions.

Ten-year results of the practical immunity investigation of apricot cv. Harlayne are presented. Two-year-old trees of cv. Harlayne were inoculated by chip-budding with six different strains and isolates of Plum pox virus (PPV). PPV inoculated trees grew in the field and were evaluated from 2001 to 2011. No PPV symptoms appeared in the leaves of cv. Harlayne within ten years (2002-2011), and within eight years (2004-2011) in the fruits and stones. None of the six isolates of three different PPV strains was detected in the leaves and fruits by ELISA. Suckers of the rootstock Prunus myrobalana developed around cv. Harlayne trees in 2005-2011 were symptomless and ELISA was negative within seven years. New trees of cv. Harlayne obtained from tested trees by budding on PPV susceptible apricot rootstock MVA-2 in 2007 were PPV free from 2008 through 2011. The presence of PPV was proved by ELISA neither in leaves of cv. Harlayne nor in rootstock MVA-2.

Sugarcane plant samples affected by the disease pokkah boeng were collected from the major sugarcane producing areas in Iran. Fifty isolates of Fusarium verticillioides were recovered from diseased sugarcanes. Results of pathogenicity tests revealed that all isolates were pathogenic to sugarcane. Four hundred and eighty-five nitrate non-utilising mutants were generated from F. verticillioides isolates. Media used for nit mutant generation included potato dextrose agar, minimal medium and Czapeck agar amended with 1.8%, 2%, 2.5%, and 3% potassium chlorate. Nit mutants were divided into three phenotypic (nit1, nit3, and nitM) classes based on their growth on different nitrogen sources in the culture media. Among the isolates tested, 280, 115 and 90 nit1, nit3, and nit M were generated, respectively. Nit mutants were used to force the heterokaryon formation to determine the distribution of VCGs and their relation to pathogenicity and geographic origin. Forty-eight VCGs of F. verticillioides were isolated from sugarcane. Forty-six of the VCGs were represented by a single isolate, whereas the remaining two comprised two isolates. None of the VCGs was common.

Choke of grasses caused by Epichloë typhina occurred in 2008 and 2009 in more than 25% of grass seed stands of timothy (Phleum pratense and P. nodosum); a lower incidence was reported in orchard grass (Dactylis glomerata). A decline in disease incidence in 2010 was caused partly by a reduction in the total area of grasses grown for seed production and partly by a decrease of older grass seed stands. The incidence of choke in timothy varieties Odenwälder and Pampas was very high; they differed statistically from the other 24 grown cultivars. No difference was found among 21 varieties of orchard grass. The highest incidence of choke was observed in varieties Comer and Dolina (timothy) and Amera (orchard grass). The incidence of choke in cultivated varieties of Phleum spp. and D. glomerata was affected by stand age (the incidence of the disease in timothy was recorded in 13% of stands in the first cropping year and in 50% of stands in the fifth cropping year). Choke disease occurred in all regions where the species were grown for seed.

Sheath rot of rice and leaf blight of wheat caused by Pseudomonas syringae pv. syringae are the important bacterial pathogens of rice and wheat in Iran. The randomly amplified polymorphic DNA (RAPD) method was used to investigate the genetic diversity of 60 strains of P. s. pv. syringae obtained from rice and wheat in different growth stages. Cluster analysis by UPGMA method showed that strains were grouped into two clusters. The AMOVA analysis indicated that about 18% of the total genetic variation existed between two populations of rice and wheat, which showed the lack of host specialization in P. s. pv. syringae strains among rice and wheat. We confirmed that high genetic heterogeneity existed in the P. s. pv. syringae strains which are detectable by RAPD analysis, and that molecular and statistical analysis of RAPD fragments can be used both to distinguish between strains and to determine relatedness between them.

Occurrences of pea aphids and their natural enemies (syrphids, mummies caused by entomopathogenic fungi Beauveria sp. and by the parasitic wasp Aphidius ervi) were compared in monocultures and mixtures of field peas and spring cereals in three seasons (2008-2010). At the beginning of colonisation, the occurrence of aphids was not substantially influenced by intercropping with cereals. However, the numbers of pea aphids located on inflorescences started to decline earlier in mixtures compared with monoculture. More syrphids (eggs + larvae) were found in mixtures than in monoculture, and more syrphid eggs were found in young aphid colonies (10 to 20 individuals) in mixtures. Intercropping did not influence the occurrence of fungal mummies (Beauveria sp.), but mixtures tended to have more aphid colonies infested by A. ervi in 2008 and 2009.