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Apate monachus (Fabricius, 1775), a bostrichid pest of pomegranate and carob trees in nurseries - Short CommunicationCarmelo Peter BonsignorePlant Protect. Sci., 2012, 48(2):94-97 | DOI: 10.17221/53/2011-PPS The attacks of adult Apate monachus (Fabricius) on pomegranate (Punica granatum L.) and carob (Ceratonia siliqua L.) trees in a plant nursery in southern Italy was described. The adult beetles produce circular holes and large sinuous tunnels on young trees that can involve the trunk and branches. The same plant can be affected by large numbers of such access holes. The adults appear during late June and reach a peak during the first three weeks of July. Given the increase in the spread of cultivation of these trees and, therefore, in the rate of spread of this pest species, further damage to crops is expected. |
Management of bacterial blight of cotton using a mixture of Pseudomonas fluorescens and Bacillus subtilisKhabbaz SALAHEDDIN, Veeramuthu VALLUVAPARIDASAN, Duraisamy LADHALAKSHMI, Rethinasamy VELAZHAHANPlant Protect. Sci., 2010, 46(2):41-50 | DOI: 10.17221/20/2009-PPS The potential of antagonistic rhizobacteria in the management of bacterial blight of cotton caused by Xanthomonas axonopodis pv. malvacearum (Xam) was evaluated under greenhouse and field conditions. In this study, 93 bacterial isolates from the rhizosphere of cotton were screened for their efficacy in inhibiting the growth of Xam in vitro. Among them, 21 isolates were found to inhibit the in vitro growth of Xam. These isolates were identified as Pseudomonas fluorescens and Bacillus subtilis based on phenotypic characteristics, biochemical properties and using 16S-23S intergenic transcribed spacer-Polymerase Chain Reaction (PCR). Among the 21 isolates, the isolates P. fluorescens Pf32 and P. fluorescens Pf93 and B. subtilis B49 exhibited the maximum inhibitory activity against Xam. Talc-based powder formulations of the effective antagonistic isolates of P. fluorescens (Pf32, Pf93) and B. subtilis (B49) were developed and evaluated individually and in combination for their efficacy in the management of bacterial blight of cotton under greenhouse and field conditions. The P. fluorescens isolates Pf32 and Pf93 and Bacillus subtilis isolate B49 survived well in the talc-based formulation for more than 90 days. The application of a mixture of Pf32, Pf93 and B49 to seed, soil and foliage significantly reduced the bacterial blight incidence and increased the plant height, number of branches and number of bolls under field conditions. The plots treated with a mixture of Pf32, Pf93 and B49 recorded the maximum yield of 1915 kg/ha and 1512 kg/ha in trial I and trial II compared to 1210 kg/ha and 987 kg/ha in the untreated control, respectively. |
Influence of growing Bt maize on Fusarium infection and mycotoxins content - a reviewJan Nedělník, Hana Lindušková, Martin KmochPlant Protect. Sci., 2012, 48(10):S18-S24 | DOI: 10.17221/36/2012-PPS The literature linking Bt maize versus non-Bt maize and the changes in the fungal microflora spectrum and in the mycotoxins content have been summarised. The European corn borer reportedly promotes the infection of maize by Fusarium spp. Stalk and ear rots caused by Fusarium spp. are often related to mycotoxin accumulation in maize kernels. As a result, food and animal feed from maize are more severely contaminated with Fusarium mycotoxins: e.g. fumonisins (FUM), deoxynivalenol (DON), and zearalenone (ZEA). Mycotoxins in field maize lead annually economic losses of hundreds of millions of dollars in all regions of the world. The insecticidal proteins in genetically modified hybrid Bt maize reduce insect damage caused by certain Lepidopteran larvae, which in turn can reduce the infection of the grain by the mycotoxigenic fungi. Where such insect damage is a major factor in mycotoxin contamination, Bt maize can lower mycotoxin levels in many cases. The protection of maize plants against insect damage (European corn borer) through the use of Bt technology seems to be one of the ways to reduce the contamination of maize by Fusarium species and mycotoxins. |
Reaction of selected apple cultivars to wilt pathogen Verticillium dahliaMuwaffaq R. KARAJEH, Saed J. OWAISPlant Protect. Sci., 2012, 48(3):99-104 | DOI: 10.17221/61/2011-PPS The reaction of five apple cultivars to olive wilt caused byVerticillium dahliae Kleb was evaluated. Five apple cultivars (Royal Gala, Delicious Anabri, Double Red, Golden Delicious, Granny Smith) and one olive cultivar (Nabali Mohassan) were inoculated with V. dahliae and grown under partially controlled greenhouse conditions. Typical symptoms of the disease were developed on the inoculated olive seedlings. However, all tested apple cultivars did not show the typical symptoms of Verticillium wilt except cv. Delicious Anbari, which showed 8.31% disease severity. The average percentage of disease severity was 61.2% in Nabali Mohassan. The pathogen was positively re-isolated from the inoculated seedlings of cvs Nabali Mohassan and Delicious Anbari after 12 months from the inoculation date. Results indicate that an apple plantation to replace dead or severely diseased olive trees infested with Verticillium wilt is an appropriate low-cost and environmentally sound IPM alternative approach to control Verticillium wilt. |
Influence of pesticide-treated seeds on survival of Mesorhizobium sp. Cicer, symbiotic efficiency and yield in chickpeaKunal, Poonam SharmaPlant Protect. Sci., 2012, 48(1):37-43 | DOI: 10.17221/54/2010-PPS Chemical seed protectants are used to reduce the adverse effects of seedling fungal pathogens or insect attack on legume pastures and crops. Chickpea seeds are also frequently treated with Mesorhizobium sp. Cicer inoculant to promote effective symbiotic nitrogen fixation (SNF), which seems to be a cost effective measure. The population of viable Mesorhizobium sp. Cicer on seeds of chickpea declined with time of storage (4°C) in pesticide treated and untreated chickpea seeds in vitro. A significant reduction in chickpea rhizobia was observed in seed treatment with Captan followed by Endosulfan and Chlorpyrifos. In a field experiment during the winter season 2006-2008, no difference in the emergence count of chickpea plants was observed. Treatments inoculated with Mesorhizobium sp. Cicer alone or along with Captan, Chlorpyrifos or Endosulfan showed improved plant growth and symbiotic parameters (plant height, nodulation, leghaemoglobin content, and nitrogen content) in comparison with the uninoculated control treatment. Significantly higher grain yield (9.6%) was observed in the treatment inoculated with Mesorhizobium sp. Cicer alone as compared to the uninoculated control. A non-significant difference in grain yield among treatments where Mesorhizobium sp. Cicer along with a mixture of fungicide and insecticides was applied was observed in contrast to the Mesorhizobium sp. Cicer treatment. In conclusion, the recommended rates of fungicide and insecticides as seed treatment were not detrimental to chickpea-Mesorhizobium sp. Cicer symbiosis, hence they can be safely used to obtain higher productivity. |
Seasonal dispersal of the Western corn rootworm (Diabrotica virgifera virgifera) adults in Bt and non-Bt maize fieldsĽudovít Cagáň, Ioan RoscaPlant Protect. Sci., 2012, 48(10):S36-S42 | DOI: 10.17221/79/2012-PPS 32 experimental plots were sown at Borovce (district Trnava) in Slovakia during 2008 with 8 maize hybrids, including coleopteran-protected MON 88017, the lepidopteran-protected MON 89034, the stacked product, MON 89034 × MON 88017, that same hybrids isoline that did not have the Bt trait or traits, and 4 commercial hybrids. Part of the fourth repetition was unexpectedly infested and damaged with the Western corn rootworm (WCR). High numbers of the WCR adults were found in the damaged plots on July 8. Adult WCR abundance remained concentrated in this area until August 12-19. The beetles apparently began to disperse during August 19-September 2, and after September 2. The trap captures increased in the uninfested areas up to September 16, no significant difference having been found in the adult WCR captures between the infested and uninfested plots, including the plots with MON 88017. Bt-maize hybrids containing MON 88017 strongly influenced the level of the WCR damage as assessed by lodging of the maize plants, and they also influenced the numbers of the WCR adults before maize flowering. We found that intensive movement of the WCR adults from the place of their origin started later in the vegetation season. |
Effects of biocontrol agents and plant products Macrophomina phaseolina and colchicine content in Gloriosa superbaDevadason Alice, Subramanian SundravadanaPlant Protect. Sci., 2012, 48(3):110-115 | DOI: 10.17221/18/2011-PPS Gloriosa superba is a medicinal plant severely infested with soil-borne Macrophomina phaseolina (Tassi) Goid. Under in vitro conditions a commercial formulation of Trichoderma viride and Pseudomonas fluorescens inhibited the mycelial growth of M. phaseolina isolates. Among the oil cake, mahua cake at 10% completely inhibited the mycelial growth of the M. phaseolina isolates. Under field conditions both the soil and foliar application of biocontrol agents is attributed to the healthy growth of G. superba crops by controlling the tuber rot disease and ultimately boosting the colchicine content. |
Occurrence of Peronospora dianthicola on carnations in the Czech RepublicIvana ŠafránkováPlant Protect. Sci., 2012, 48(2):72-73 | DOI: 10.17221/63/2011-PPS A downy mildew disease was observed on leaves of Dianthus chinensis L. cv. Scarlet in Brno in June 2011. Characteristics of visual symptoms and microscopic features are described. The morphology of the fungus was typical of Peronospora dianthicola, conforming to the published description by Francis (1983). P. dianthicola causing leaf spots on Dianthus has been recorded for the first time in the Czech Republic. |
Biology of Trioza apicalis - a reviewPavel LáskaPlant Protect. Sci., 2011, 47(2):68-78 | DOI: 10.17221/1/2011-PPS The morphology and biology of immature stages and the distinguishing characters of generations in summer are briefly reviewed. The time of migration of the overwintered generation and the use of the median flight time are given. The longevity of overwintered adults, and the start and course of oviposition by overwintered females were observed mainly during June and July. The interval between adult emergence and flights from carrots appears to be very short, 2-3 days. Departure from developmental summer host plants culminates at the beginning of September. The sex ratio of the overwintered generation is not persistent, since it is usually female-biased. In emerged adults in summer the ratio is 50:50, with weak protandry. The systemic action of sucking for the curling of leaves was found by Láska already in 1964. Inliterature records, both subspecies of Daucus carota dominate as developmental hosts, more recently Coriandrum sativum was shown to be more suitable than Petroselinum hortense. Norway spruce, and to a lesser extent other conifers, are predominantly mentioned as overwintering shelter plants. It is not clear how overwintering occurs in regions without coniferous forests, and only undefined shrubs or trees are given in the literature. The first damage was reported inDenmark about in 1896, spreading from about 1918 over just a few years to the other Fennoscandian countries, and later in some other European countries. The spring migration is discussed, which occurs in central and northern Europe on the same date, perhaps explicable by the orientation of this pest or its particular populations to long days, despite the climate and phenology of each region. It is hypothesised that a particularly aggressive race evolved inSjaelland (Denmark) at the turn of the nineteenth and twentieth century, which later spread to other regions of northern and centralEurope. |
Pathogenicity of three commercial products of entomopathogenic fungi, Beauveria bassiana, Metarhizum anisopilae and Lecanicillium lecanii against adults of olive fly, Bactrocera oleae (Gmelin) (Diptera: Tephritidae) in the laboratoryMahmoud Farag MahmoudPlant Protect. Sci., 2009, 45(3):98-102 | DOI: 10.17221/34/2008-PPS The pathogenicity of entomopathogenic fungi, Beauveria bassiana, Metarhizum anisopilae and Lecanicillium lecanii, was evaluated against adults of the olive fly Bactrocera oleae (Gmelin) under laboratory conditions by two ways, contact bioassays and oral bioassays. The results showed that oral bioassays caused higher mortality after four treatments than the used contact bioassays. Moreover, the virulence ofL. lecanii was higher than the virulence of B. bassiana and M. anisopilae in both ways of experiment. Lethal time (LT50) was shorter in oral bioassays than in contact bioassays in all treatments. It was 14.67, 8.30 and 5.43 days for B. bassiana, M. anisopilae and L. lecanii with oral treatment while it was 16.6, 26.07 and 12.59 days for B. bassiana, M. anisopilae and L. lecanii, respectively, with contact treatment. The slope values were 2.41, 2.55 and 2.37 for contact bioassays and 1.64, 1.69 and 1.61 for oral bioassays of B. bassiana, M. anisopilaeand L. lecanii, respectively. The mortality response to the interaction between B. bassiana and M. anisopilae was synergistic while the interaction between B. bassiana + L. lecanii and M. anisopilae + L. lecanii showed an antagonistic response. |
Phytophthora plurivora T. Jung & T. I. Burgess and other Phytophthora species causing important diseases of ericaceous plants in the Czech RepublicMarcela Mrázková, Karel Černý, Michal Tomšovský, Veronika StrnadováPlant Protect. Sci., 2011, 47(1):13-19 | DOI: 10.17221/3108-PPS Ornamental nurseries, garden centres, public gardens and urban greenery in the Czech Republic were surveyed in 2006-2009 for the presence of Phytophthora spp. and the diseases they cause on ericaceous plants. Diseased plants such as Rhododendron spp., Pieris floribunda, Vaccinium sp., and Azalea sp. showed various symptoms including leaf spot, shoot blight, twig lesions or stem, root and collar rot. Nearly 140 Phytophthora isolates were collected from symptomatic plants in different areas of the country. Of the Phytophthora spp. on ericaceous plants or in their surroundings, P. plurivora appeared to be the most common species. Herein, we focus on the most frequently occurring species, P. plurivora, and describe its morpho-physiological and pathogenicity features and confirm its identity based on ITS sequences of rDNA. In addition, we give a list of other Phytophthora spp. including P. cactorum, P. cambivora, P. cinnamomi, P. citrophthora, P. megasperma, P. multivora, P. ramorum, and P. gonapodyides that we identified on the basis of their cultural and morphological characteristics and DNA sequences. We also discuss their importance in cultivated and natural ecosystems. |
Field efficacy of Helicoverpa armigera nucleopolyhedro-virus isolates against H. armigera (Hübner) (Lepidoptera: Noctuidae) on cotton and chickpea in Tamil NaduSubramanian Jeyarani, Natarajan Sathiah, Palaniappan KaruppuchamyPlant Protect. Sci., 2010, 46(3):116-122 | DOI: 10.17221/30/2009-PPS Field efficacy of seven geographical isolates of Helicoverpa armigera nucleopolyhedrovirus (HaNPV) along with an insecticide control was evaluated against H. armigera on cotton and chickpea in the Coimbatore district of Tamil Nadu, India. Among the HaNPV isolates, CBE I (Coimbatore) and NEG (Negamum) applied at 3.0 × 1012 POB/ha to cotton and 1.5 × 1012 POB/ha to chickpea with an adjuvant, crude sugar, significantly reduced the H. armigera larval population and increased the yield. CBE I and NEG recorded the highest yield of 2038 kg/ha and 2033 kg/ha, which was on a par with endosulfan (2026.7 kg/ha) with cost/benefit ratios of 1:2.32, 1:2.48, and 1:1.12, respectively, on cotton. In chickpea grain yields of 980, 983, and 973.3 kg/ha and cost/benefit ratios of 1:1.36, 1:1.48 and 1:0.87, respectively, in CBE I, NEG and endosulfan treated plots were obtained. The isolate RAJ (Rajasthan) recorded the lowest yield comparable to that of the untreated control in both crops. |
Toxicity and biochemical impacts of some new insecticide mixtures on cotton leafworm Spodoptera littoralis (Boisd.)Ahmed E. M. ABD EL-MAGEED, Shehata E. M. SHALABYPlant Protect. Sci., 2011, 47(4):166-175 | DOI: 10.17221/3/2011-PPS The susceptibility to five new insecticide mixtures: chlorosan, feroban, cygron, engeo, and kingbo was studied in the 2nd and 4th instar larvae of the cotton leafworm Spodoptera littoralis (Boisd.). The efficiency and residual effects of these compounds against S. littoralis under field conditions were also investigated. Obtained results revealed that feroban was the most effective compared with the other toxicants, while engeo was the least toxic insecticide in both instars after 2 and 5 days from treatment. Data also indicated that feroban had the longest half-life (Lt50) while engeo recorded the shortest one. Biochemical analysis showed that the tested compounds caused pronounced changes in acetyl cholinesterase and phenol oxidase. |
Professor Aleš Lebeda at sixty - Biografical noticeV. Kůdela, K. Reinink, R. Singh, M.P. WidrlechnerPlant Protect. Sci., 2011, 47(2):79-82 | DOI: 10.17221/20/2011-PPS |
Contribution to the knowledge of diversity of Fusarium associated with maize in MalaysiaMohd Zainudin Nur Ain Izzati, Abd Razak Azmi, Mohamed Sidique Siti Nordahliawate, Johari NorazlinaPlant Protect. Sci., 2011, 47(1):20-24 | DOI: 10.17221/52/2008-PPS The Fusarium species associated with maize are widely distributed in Malaysia. Eight Fusarium species were obtained in this country. A series of field samplings was conducted from 2006 to 2008, when 167 Fusarium isolates were obtained from maize plants in seven locations throughout Malaysia. The determination was based on micro- and macromorphological features (growth rates, colony features, mode of production of microconidia, macroconidia, conidiophores, and chlamydospores). F. proliferatum (29.9% isolates), F. semitectum (22.2% isolates), F. verticillioides (13.7% isolates), and F. subglutinans (12.6% isolates) were found out most frequently. F. equiseti, F. pseudograminearum, F. oxysporum, and F. solani were also isolated. This is the first report on the occurrence of F. equiseti, F. pseudograminearum, and F. subglutinans associated with maize plants in Malaysia. |
Biological efficacy of some biorational and conventional insecticides in the control of different stages of the Colorado potato beetle, Leptinotarsa decemlineata (Say) (Coleoptera: Chrysomelidae)Mohamed A. M. OsmanPlant Protect. Sci., 2010, 46(3):123-134 | DOI: 10.17221/27/2009-PPS The biological efficacy of some biorational and conventional insecticides against different stages of Colorado potato beetle, Leptinotarsa decemlineata (Say) (Coleoptera: Chrysomelidae) was evaluated under laboratory and semi-field conditions. Seven different commercial products were tested, including the biorational insecticides: Spinosad, Mectin, Fitoverm, Match, Neemix in addition to two conventional insecticides: Actara and Actellic. Data indicated that all tested insecticides showed low toxic effects to L. decemlineata eggs, but most hatching neonates died shortly after hatching. All tested insecticides at their field rates showed high toxicity to larvae of L. decemlineata. The highest mortality was obtained in earlier instars, as compared to older ones, and mortality increased with the time of exposure. Moreover, the lower concentrations (up to 25% of the field rate) of Actara, Mectin, Spinosad, and Fitoverm showed high efficacy against L. decemlineata third instar larvae. Also, Actara caused the highest mortality in L. decemlineata adults, followed by Spinosad, Mectin, and Fitoverm as compared to Actellic, Match, and Neemix. In pupal bioassay, Fitoverm caused the greatest reduction in L. decemlineata adult emergence followed by Mectin, Actara, Actellic and Spinosad. In translocation bioassays, Actara caused the highest mortality in L. decemlineata 3rd instar larvae or adults followed by Spinosad and Mectin. The residual activity of tested insecticides against third instar larvae was also evaluated. Actara, Spinosad, and Mectin were more persistent under field conditions, consequently the mortality rates after 30 days of application were 46.67%, 44.44%, and 35.56%, respectively. |
Professor Vladimír Táborský, MSc., PhD., OctogenarianP. Ryšánek, J. PolákPlant Protect. Sci., 2011, 47(3):131-132 | DOI: 10.17221/2814-PPS |
M. Spencer, A. Lebeda (eds) - Mass Screening Techniques for Selecting Crops Resistant to Disease - Book ReviewK. VeverkaPlant Protect. Sci., 2011, 47(1):42 | DOI: 10.17221/994-PPS |
Anthracnose field evaluation of sorghum germplasm from BotswanaJohn E. ErpeldingPlant Protect. Sci., 2011, 47(4):149-156 | DOI: 10.17221/34/2010-PPS Sorghum anthracnose is a disease of worldwide importance and host-plant resistance is the most practical method of disease management. In this study, 154 sorghum accessions from the Botswana collection maintained by the United States National Plant Germplasm System were inoculated with Colletotrichum sublineolum and evaluated for disease resistance at the Tropical Agriculture Research Station in Isabela, Puerto Rico during 2007 and 2008. A resistant response was observed for 69 accessions in 2007 and for 48 accessions in 2008 with no acervuli development observed on inoculated leaves. The low frequency of resistant germplasm is expected from a region of low annual rainfall. However, disease severity was low for the susceptible accessions with a mean severity of 11% for the 85 susceptible accessions observed in 2007 and 17% for the 106 susceptible accessions identified in 2008. The highest frequency of resistant accessions was observed for the Ngamiland district with 58% of the accessions rated as resistant, whereas the frequency of resistant accessions ranged from 22% to 36% for the other districts. The lowest mean disease severity was also observed for the susceptible accessions from the Ngamiland district with the highest mean disease severity observed for susceptible accessions from the Kgatleng district. The resistant accessions identified in this study would be useful for the development of disease resistant varieties and the results indicated an ecogeographic association with disease resistance. |
Viruses of blackthorn and road-bordering trees of plum, myrobalan, sweet and sour cherries in the Czech RepublicJaroslav PolákPlant Protect. Sci., 2007, 43(1):1-4 | DOI: 10.17221/2351-PPS The distribution of Plum pox virus (PPV), Prune dwarf virus (PDV), Prunus necrotic ringspot virus (PNRSV), Apple chlorotic ringspot virus (ACLSV) and Apple mosaic virus (ApMV) in naturally growing shrubs of blackthorn and road-bordering trees of plum and myrobalan, and of PPV, PDV, PNRSV and Cherry leafroll virus (CLRV) in sweet and sour cherry trees were investigated. The most widely distributed viruses were PPV in plums (74% of the investigated trees were infected); PPV, PDV, and PNRSV in myrobalans (26%, 11% and 18%, respectively), PDV in blackthorns (27%), and PDV and PNRSV in cherries (25% and 22%). PPV was not detected in sweet and sour cherries. The incidence of ACLSV and ApMV was negligible in individually growing trees of the genus Prunus in the Czech Republic. |
Resistance of apple varieties and selections to Erwinia amylovora in the Czech RepublicJosef KORBA, Jana ŠILLEROVÁ, Václav KŮDELAPlant Protect. Sci., 2008, 44(3):91-96 | DOI: 10.17221/19/2008-PPS Sixty-four apple cultivars and selections of potential interest to apple producers and plant breeders in the Czech Republic were tested for their relative resistance to the fire blight pathogen over six years. Level of fire blight resistance was evaluated according to the extent of lesion development on the shoots tips after artificial inoculation in experimental plots under insectproof nets. Cultivars Quinte (resistant) and Yellow transparent (high susceptible) were included in the tests. Of 64 apple cultivars and selections tested, none were high resistant, 3.1% were evaluated as resistant, 10.9% moderately resistant, 57.8% moderately susceptible, 21.9% susceptible and 6.3% high susceptible. Resistant apple genotypes, showing blight necrosis of shoots of 11-12%, were only cultivars Selena and Quinte. Moderately resistant genotypes (blight necrosis 13.1-25.0%) were Kordona, Golden Smoothee, Julia, HL 323, Melodie, HL 421 and S 634/3. High susceptible genotypes (blight necrosis more then 80.1%) were comprised cultivars Vesna, Topas, Yellow transparent and Vanda. The remaining genotypes were moderately susceptible (blight necrosis 26.1-60.0%) and susceptible (blight necrosis 60.1-80.0%). During six experimental years, quantitative variability was recorded in the blight score. Differences between cultivars in susceptibility to fire blight were often statistically significant. |
Peronospora hariotii on Buddleja in the Czech RepublicIvana Šafránková, Jiří MüllerPlant Protect. Sci., 2009, 45(1):12-15 | DOI: 10.17221/44/2008-PPS A downy mildew was observed on Buddleja × weyeriana Weyer ex Rehd. (B. davidii × globosa) cv. Sungold in a nursery in the northern part of the Czech Republic in July 2008. This downy mildew disease of Buddleja (Butterfly Bush) had been unknown in the country so far. Characteristics of visual symptoms and microscopic features are described. The morphology of the fungus was typical for Peronospora hariotii, conforming to the published description by GÄUMANN (1919). The sexual stage was not found. This is the first report of Peronospora hariotii causing leaf spot disease on Buddleja in the Czech Republic. |
Bifenazate, a prospective acaricide for spider mite (Tetranychus urticae Koch) control in Czech hopsJosef VostřelPlant Protect. Sci., 2010, 46(3):135-138 | DOI: 10.17221/54/2009-PPS Bifenazate, a new selective carbazate acaricide, seems to be a very good substitute for propargite to control spider mites (Tetranychus urticae Koch) on hops in the Czech Republic. To investigate the phenomenon of T. urticae resistance to this compound, 20 samples of field populations were taken in several Czech and Moravian hop-growing regions in 2006 and 2007 and subjected to laboratory tests in a Potter tower. Low values of C100 M (100% mortality) in comparison with the supposed registered concentration reveal that bifenazate may become a useful acaricide within the anti-resistant strategy against T. urticae not only in Czech but also in all European hop-growing regions. |
Communities of oribatid mites and heavy metal accumulation in oribatid species in agricultural soils in Egypt impacted by waste waterHamdy Mahmoud EL-SHARABASY, Ahmed IBRAHIMPlant Protect. Sci., 2010, 46(4):159-170 | DOI: 10.17221/31/2010-PPS The continued use of waste water for irrigation of agricultural fields in Egypt may lead to accumulation of heavy metals in soils and adverse effects on soil-living communities. We investigated responses of oribatid communities to heavy metal contamination in mango plantations irrigated by the Ismailia canal in the Suez region. Mean concentrations of heavy metals determined in irrigation water were considerably above the recommended levels. Concentrations of metals in agricultural soil were however below the permissible levels. A comparison with concentrations of a typical uncontaminated soil in this area revealed that the Ismailia water canal used for irrigation of agricultural land has elevated levels of heavy metals. The results of our ecological survey showed that the abundance and structure of the soil oribatid communities were not influenced by levels of heavy metals in the soil. We also showed that the diversity index can be a valuable tool for assessing the possible impact of pollutants on different species of oribatid mites. The oribatid species appeared to be accumulating different amounts of heavy metals when characterised by their bioconcentration factors. Most species were poor zinc accumulators. The accumulation of heavy metals in the body of oribatids was not strictly determined by their body size or by the trophic level. In conclusion, our study showed that mango plantations impacted by waste water from the Ismailia canal are accumulating heavy metals in their soils above the background concentrations, but ecological effects on soil-living communities are not apparent yet. |
Effect of the mycoflora of ergot (Claviceps purpurea)sclerotia on their viabilityMichal ONDŘEJ, Bohumír CAGAŠ, Eliška ONDRÁČKOVÁPlant Protect. Sci., 2010, 46(2):66-71 | DOI: 10.17221/48/2009-PPS Twenty fungal species were isolated from sclerotia of ergot (Claviceps purpurea) originating from rye. In in vitro tests with the anamorphic stage of ergot (known as Sphacelia segetum) high mycoparasitic activity was exhibited only by two of them - Clonostachys rosea and Trichoderma harzianum, moderate mycoparasitic activity was detected in Ulocladium sp., Clonostachys catenulata, Trichoderma hamatum, and Trichothecium roseum. In in vitro tests of mycoparasitic activity with sclerotia of the fungus Sclerotinia sclerotiorum their rapid and total destruction was brought about only by the fungi Clonostachys rosea and Trichoderma harzianum. The viability of overwintering ergot sclerotia in the soil was influenced by their placement, age, depth of placement and treatment with a conidial suspension of the fungus Clonostachys rosea. The highest viability values were reported in fresh one-year-old sclerotia. In two-year-old sclerotia their viability was reduced and their sensitivity to microbial activity was higher. The sclerotia aged 3 years or more did not germinate and were all microbiologically degraded in the soil. More than 80% of degradation of sclerotia which were 1 to 2 years old was caused by the fungus Clonostachys rosea. The degradation of sclerotia aged 3 to 4 years was brought about by bacteria, soil edafauna (mites, nematodes) and fungi of the genera Trichoderma, Fusarium, Clonostachys, etc. |
First Record of Horidiplosis ficifolii Harris 2003 (Diptera: Cecidomyiidae) in the Czech RepublicJakub BERÁNEK, Ivana ŠAFRÁNKOVÁPlant Protect. Sci., 2010, 46(4):189-191 | DOI: 10.17221/53/2009-PPS In November 2009 the gall midge species Horidiplosis ficifolii Harris 2003 was detected in the Czech Republic on leaves of an ornamental fig Ficus microcarpa. The insect is native to South East Asia, where it lives on the genus Ficus. No information is currently available on the prevalence of the pest in the countries of its origin. Imported Ficus plants from China into the Netherlands are sometimes heavily infested with the gall midge. In Europe it is also known from Denmark and the United Kingdom. As Horidiplosis ficifolii is a tropical species, no environmental and social damage is expected. |
Some notes on the occurrence of plant parasitic nematodes of fruit trees in SlovakiaMarta Lišková, Nicola Sasanelli, Trifone D'addabboPlant Protect. Sci., 2007, 43(1):26-32 | DOI: 10.17221/2349-PPS Forty plant parasitic nematode species were identified in soil of fruit orchards in the southeastern and southwestern areas of the Danubian Lowlands and East Slovak Lowland, characterised by light sandy soil of riverine origin, locally combined with drift sand landscape. They were Ditylenchus dipsaci, Helicotylenchus canadensis, H. digonicus, H. dihystera, H. multicinctus, Rotylenchus agnetis, R. fallorobustus, R. goodeyi, Rotylenchulus borealis, Pratylenchus crenatus, P. penetrans, P. pratensis, P. thornei, Zygotylenchus guevarai, Pratylenchoides laticauda, Meloidogyne hapla, Bitylenchus dubius, Tylenchorhynchus cylindricus, Merlinius nanus, Macroposthonia antipolitana, M. rustica, M. xenoplax, Paratylenchus bukowinensis, P. elachistus, P. nanus, P. projectus, Longidorus elongatus, L. euonymus, L. juvenilis, unidentified Longidorus sp., Xiphinema diversicaudatum, X. italiae, X. pachtaicum, X. taylori, X. vuittenezi, Trichodorus primitivus, T. sparsus, T. viruliferus, Paratrichodorus macrostylus and P. pachydermus. Many of the observed species are phytopathologically important parasites of fruit trees and some are also vectors of plant viruses. The frequency of occurrence, dominance and abundance of individual species were determined. |
Cohabitation and intraleaf distribution of phytoseiid mites (Acari: Phytoseiidae) on leaves of Corylus avellanaJan KABÍČEKPlant Protect. Sci., 2008, 44(1):32-36 | DOI: 10.17221/3/2008-PPS Leaves from uncultivated and unsprayed hazelnut shrubs, Corylus avellana, were sampled from June to August 2005 to obtain information on the phytoseiid mite taxocenoses, population density and intraleaf distribution. Six phytoseiid mite species were identified, of which three, Kampimodromus aberrans, Euseius finlandicus and Neoseiulella tiliarum, were more abundant. The eudominant, slowly moving K. aberrans was found on all leaf samples. Phytoseiid population density averaged 3.16 mites per hazelnut leaf. While on most leaves only one phytoseiid species was found, on some there was cohabitation of two (rarely three) species. The three frequent species mostly inhabited the sheltered microhabitat at the veins of leaves of C. avellana. |
The potential of Beauveria brongniartii and botanical insecticides based on Neem to control Otiorhynchus sulcatus larvae in containerised plantsJolanta KOWALSKAPlant Protect. Sci., 2008, 44(1):37-40 | DOI: 10.17221/521-PPS Otiorhynchus sulcatus is considered as an important pest of strawberry fields and on potted ornamental plants. The efficacy to control this pest by new Polish products containing azadirachtin and the entomopathogenic fungus Beauveria brongniartii were tested. The aim of the laboratory investigation was to assess the influence of different forms of azadirachtin (A and B) and the entomopathogen on mortality and physiological development of the insect. Mortality after treatment ranged between 86-93%. There were significant differences in the mean number of surviving stages of the insect between Beauveria and neem treatments, but the final total mortality was not statistically different. Sensitivity of all developmental stages to the fungus was observed. In the neem treatments the physiological development of larvae was completely stopped. The level of control achieved by Beauveria and neem for use in outdoor containers is acceptable for practical application. |
