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Efeito de genótipos de sorgo sobre o predador Chrysoperla externa (Hagen) (Neuroptera: Chrysopidae) alimentado com Schizaphis graminum (Rondani) (Hemiptera: Aphididae)

FIGUEIRA, LILIANE K.; Lara, Fernando Mesquita; CRUZ, IVAN
Fonte: Sociedade Entomológica do Brasil Publicador: Sociedade Entomológica do Brasil
Tipo: Artigo de Revista Científica Formato: 133-139
POR
Relevância na Pesquisa
65.9%
O trabalho objetivou avaliar o efeito indireto da resistência de genótipos de sorgo sobre o predador Chrysoperla externa (Hagen) usando o pulgão Schizaphis graminum (Rondani) como presa. Os genótipos usados no estudo foram: GR 11111 e TX 430 x GR 111 (resistentes), GB 3B (moderadamente resistente) e BR 007B (suscetível). Larvas recém-eclodidas foram confinadas individualmente em recipientes de vidro e alimentadas com S. graminum, criados separadamente em cada um dos quatro genótipos. Após a emergência, os adultos obtidos de cada tratamento foram sexados e agrupados aos casais, colocados em gaiolas contendo dieta à base de levedo de cerveja e mel. Os insetos foram observados diariamente da fase jovem até o período de 60 dias após a emergência do adulto. Genótipos com maior grau de resistência proporcionaram maior consumo de pulgões pelo predador, porém menor peso a este. Quando os pulgões foram criados no genótipo resistente GR 11111, o peso das larvas, sobrevivência da pré-pupa e longevidade da fêmea do predador foram inferiores. As associações positivas observadas entre o predador, C. externa, e o genótipo resistente, TX 430 x GR 111, e entre o predador e o genótipo moderadamente resistente GB 3B, evidenciaram a possibilidade de integração entre os dois métodos de controle: resistência de plantas e controle biológico.; The work aimed to evaluate the indirect effect of sorghum genotypes resistance on biological aspects of the predator Chrysoperla externa (Hagen) using the aphid Schizaphis graminum (Rondani) as prey. The genotypes used in the study were: GR 11111 and TX 430 x GR 111 (resistant)...

Relação predador: presa de Chrysoperla externa (Hagen) (Neuroptera: Chrysopidae) para o controle do pulgão-verde em genótipos de sorgo

Figueira, Liliane K.; Lara, Fernando Mesquita
Fonte: Sociedade Entomológica do Brasil Publicador: Sociedade Entomológica do Brasil
Tipo: Artigo de Revista Científica Formato: 447-450
POR
Relevância na Pesquisa
65.92%
O uso da resistência de plantas associado a agentes de controle biológico pode ser uma alternativa viável no controle de Schizaphis graminum (Rondani) em sorgo. Objetivou-se estudar diferentes relações predador:presa em genótipos de sorgo resistente (TX 430 x GR 111), moderadamente resistente (GB 3B) e suscetível (BR 007B) para o controle do pulgão-verde por Chrysoperla externa (Hagen). Para isso foram realizadas, em condições de casa-de-vegetação, liberações do crisopídeo nas relações predador:presa de 1:5; 1:10; 1:25 e 1:50. O genótipo TX 430 x GR 111 foi o mais eficiente no controle do pulgão-verde, S. graminum, assim como as relações predador:presa de 1:5 e de 1:10 nos três genótipos. A interação resistência de plantas e controle biológico foi positiva e permitiu controle acima de 80% nas relações predador:presa de 1:5 e 1:10 no material resistente TX 430 x GR 111; no genótipo GB 3B o melhor controle foi obtido com 1 predador: 5 presas.; The use of host plant resistance associated with biocontrol agents may be a viable alternative to Schizaphis graminum (Rondani) control in sorghum. This work aimed to study different predator:prey ratios on genotype resistant (TX 430 x GR 111), moderately resistant (GB 3B) and susceptible (BR 007B) for the aphid control by the predator Chrysoperla externa (Hagen). Thus...

Seleção de introduções do gênero Brachiaria (Griseb) resistentes à cigarrinha Zulia entreriana (Berg) (Homoptera: Cercopidae)

Valério,José R.; Jeller,Helma; Peixer,Janice
Fonte: Sociedade Entomológica do Brasil Publicador: Sociedade Entomológica do Brasil
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/08/1997 PT
Relevância na Pesquisa
65.97%
Spittlebugs are the most damaging pasture pests in tropical America where extensive monocultures of Brachiaria decumbens cv. Basilisk have favoured the buildup of spittlebug populations. Under severe spittlebug attack, the entire above-ground portion of the plant appears dry and dead, reducing the stocking rates of damaged pastures. Host plant resistance is a low-cost method of controlling spittlebugs, which farmers can easily adopt. High level of spittlebug resistance is found in the cultivar B. brizantha cv. Marandu, but it requires more fertile soils. A Brachiaria germplasm provided by the International Center for Tropical Agriculture and available at the National Center for Beef Cattle Research (CNPGC) has been screened for spittlebug resistance. In the present study 30 introductions of Brachiaria were evaluated for resistance to the spittlebug Zulia entreriana (Berg), based on nynphal survival and period. Three introductions (BRA 1945, BRA 3115 and BRA 3425), all B. brizantha, were selected as resistant. Given the great number of available introductions and even hibrids resulting from the breeding program, this test has been done routinely at the CNPGC in the search for sources of resistance. Complementary evaluations aiming the releasing of new spittlebug resistant Brachiaria cultivars are in progress.

Current Status of the Availability, Development, and Use of Host Plant Resistance to Nematodes

Roberts, Philip A.
Fonte: Society of Nematologists Publicador: Society of Nematologists
Tipo: Artigo de Revista Científica
Publicado em /06/1992 EN
Relevância na Pesquisa
65.9%
Host plant resistance (HPR) to nematodes has been identified in many major crops and related wild germplasm. Most HPR is to the more specialized, sedentary endoparasitic genera and species, e.g., Globodera, Heterodera, Meloidogyne, Nacobbus, Rotylenchulus, and Tylenchulus. Some HPR has been developed or identified also to certain migratory endoparasites (Aphelenchoides, Ditylenchus, Pratylenchus, Radopholus) in a few hosts. Commercial use of HPR remains limited, despite its benefits to crop production when deployed appropriately. Restricted use and availability of HPR result from problems associated with transfer of resistance into acceptable cultivars. Difficulties occur in gene transfer to acceptable cultivars because of incompatibility barriers to hybridization or linkage to undesirable traits, for example in cucurbitaceous and solanaceous crops and sugarbeet. Specificity of HPR to only one species, or one or few pathotypes, as it relates to resistance durability and nematode virulence, and HPR response to abiotic factors such as high soil temperature, also limit availability and utility. A scheme for HPR development is presented to emphasize nematology research and information requirements for expanding HPR use in nematode control programs...

An overview of NMR-based metabolomics to identify secondary plant compounds involved in host plant resistance

Leiss, Kirsten A.; Choi, Young H.; Verpoorte, Robert; Klinkhamer, Peter G. L.
Fonte: Springer Netherlands Publicador: Springer Netherlands
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
66.16%
Secondary metabolites provide a potential source for the generation of host plant resistance and development of biopesticides. This is especially important in view of the rapid and vast spread of agricultural and horticultural pests worldwide. Multiple pests control tactics in the framework of an integrated pest management (IPM) programme are necessary. One important strategy of IPM is the use of chemical host plant resistance. Up to now the study of chemical host plant resistance has, for technical reasons, been restricted to the identification of single compounds applying specific chemical analyses adapted to the compound in question. In biological processes however, usually more than one compound is involved. Metabolomics allows the simultaneous detection of a wide range of compounds, providing an immediate image of the metabolome of a plant. One of the most universally used metabolomic approaches comprises nuclear magnetic resonance spectroscopy (NMR). It has been NMR which has been applied as a proof of principle to show that metabolomics can constitute a major advancement in the study of host plant resistance. Here we give an overview on the application of NMR to identify candidate compounds for host plant resistance. We focus on host plant resistance to western flower thrips (Frankliniella occidentalis) which has been used as a model for different plant species.

Variation of Resistance in Barley Against Biotypes 1 and 2 of the Russian Wheat Aphid (Hemiptera: Aphididae)

Murugan, M.; Khan, S. A.; Sotelo Cardona, P.; Vargas Orozco, G.; Viswanathan, P.; Reese, J.; Starkey, S.; Smith, C. M.
Fonte: Oxford University Press Publicador: Oxford University Press
Tipo: Artigo de Revista Científica Formato: text/html
EN
Relevância na Pesquisa
65.88%
The Russian wheat aphid, Diruaphis noxia (Kurdjumov) (Hemiptera: Aphididae), is globally one of the most devastating pests of bread wheat, Tritium aestivum L.; durum wheat, Triticum turgidum L.; and barley, Hordeum vulgare L. Host plant resistance is the foundation for cereal insect pest management programs, and several sources of D. noxia resistance have been incorporated in cultivars to manage D. noxia damage. The emergence of D. noxia North American biotype 2 (RWA2) in Colorado has made all known Dn genes vulnerable except the Dn7 gene from rye, Secale cereale, and has warranted exploration for sources of resistance to both RWA1 and RWA2. The category of resistance in resistant donor plants may exert selection pressure over the aphid population to form a new virulent population. In the current study, we report tolerance and antibiosis resistance to RWA1 and RWA2 in the barley genotype ‘Stoneham’. The rate and degree of expression of resistance in Stoneham against RWA1 and RWA2, although not similar, are greater than the partial resistance in ‘Sidney’. Antixenosis resistance to RWA1 or RWA2 was not observed in Sidney or Stoneham. The tolerance identified in Stoneham is encouraging because it may delay D. noxia biotype selection and fits well in a dryland barley cropping system.

Detached Leaf and Whole Plant Assays for Soybean Aphid Resistance: Differential Responses Among Resistance Sources and Biotypes

Michel, Andrew P.; Rouf Mian, M. A.; Horacio Davila-Olivas, Nelson; Cañas, Luis A.
Fonte: Oxford University Press Publicador: Oxford University Press
Tipo: Artigo de Revista Científica Formato: text/html
EN
Relevância na Pesquisa
66.02%
The soybean aphid, Aphis glycines Matsumura, is a pest of cultivated soybean, Glycine max (L.) Merr., in North America. Recent developments in host plant resistance studies have identified at least four soybean aphid resistance genes (Rag1–4) and two soybean aphid biotypes (biotype 1 and 2), defined by differential survivability on resistant soybean. Detached soybean leaves were tested as a more rapid and practical assay to assess host plant resistance and virulence. Two susceptible lines (‘Wyandot’ and ‘Williams 82’) and two resistant lines (PI 243540 and PI 567301B) were examined. Various life history characteristics were compared among aphids on whole plants and detached leaves. Results indicated that resistance to soybean aphid was lost using detached leaves of PI 567301B but retained with PI 243540. To test for aphid virulence, net fecundities were compared among biotype 1 and biotype 2 after rearing on detached leaves of the resistant ‘Jackson’ (to which biotype 2 is virulent). A significant difference was detected in net fecundities among biotypes on detached leaves of Jackson and used to predict growth rates and virulence from 30 field-collected individuals of unknown virulence. No field individuals matched biotype 2 predictions...

Resistance to Rhopalosiphum padi (Homoptera: Aphididae) in Wheat Germplasm Accessions

Hesler, L. S.; Riedell, W. E.; Kieckhefer, R. W.; Haley, S. D.; Collins, R. D.
Fonte: Oxford University Press Publicador: Oxford University Press
Tipo: Artigo de Revista Científica Formato: text/html
EN
Relevância na Pesquisa
65.91%
Studies compared and characterized host plant resistance to Rhopalosiphum padi (L.) (bird cherry-oat aphid) among promising accessions of hexaploid wheat, Triticum aestivum L. Resistance was assessed for 7 wheat accessions. R. padi populations did not increase uniformly over time or by accession. After 7 d, accessions did not differ in numbers of R. padi, but by 11 d, MV4 had fewer R. padi per plant than other accessions except MV8 and Jubilejnaja 50. At 14 d, MV4 had fewer R. padi than other accessions except MV8; Jubilejnaja 50 had fewer aphids per plant than remaining accessions, but more than MV4 or MV8. R. padi nymphs developed more slowly on MV4 than other accessions, but plant accession did not affect the number of progeny that R. padi produced. The intrinsic rate of increase of R. padi was less on MV4 than on Ommid. R. padi produced a higher proportion of alatae on accession MV4, whereas they produced a lower percentage of alates on the accession Vista. In choice tests, distribution of alatae or apterae did not differ among wheat accessions. Low levels of antibiosis in MV4 may limit infestations of R. padi on wheat, and this may indirectly slow the spread of barley yellow dwarf virus and reduce the need for aphicide applications in wheat fields.

Identification of Sources of Plant Resistance to Diaprepes abbreviatus(Coleoptera: Curculionidae) by Three Bioassays

Lapointe, S. L.; Shapiro, J. P.; Bowman, K. D.
Fonte: Oxford University Press Publicador: Oxford University Press
Tipo: Artigo de Revista Científica Formato: text/html
EN
Relevância na Pesquisa
75.88%
Host plant resistance to the root weevil Diaprepes abbreviatus (L.) was assessed for 3 citrus rootstock cultivars, 5 promising hybrid rootstocks, and 3 citroid fruit trees using 3 bioassay methods: a pot bioassay with 1-yr seedlings; a new, 21-cm plastic cell bioassay with 5-mo seedlings; and a diet incorporation bioassay. The plastic cell bioassay is a more rapid screening method and is capable of evaluating a larger number of entries in a shorter period compared with current methods. The 3 bioassays yielded similar results. Larval growth was inhibited by 2 of the remote citroid fruit trees, Murraya koenigii (L.) Sprengel and Glycosmis pentaphylla (Retzius) Correa, compared with growth on commercial rootstock cultivars. Specifically, larvae allowed to feed on roots of M. koenigii or G. pentaphylla gained less weight compared with larvae fed on the commercial rootstock cultivar ‘Swingle’ [Citrus paradisi Macfayden × Poncirus trifoliata (L.) Rafinesque-Schmaltz]. The resistance of G. pentaphylla confirms previous reports. M. koenigii is a new source of resistance to D. abbreviatus.

Comparison of Screening Techniques for Western Corn Rootworm (Coleoptera: Chrysomelidae) Host-Plant Resistance

Knutson, Robert J.; Hibbard, Bruce E.; Barry, B. Dean; Smith, Vincent A.; Darrah, Larry L.
Fonte: Oxford University Press Publicador: Oxford University Press
Tipo: Artigo de Revista Científica Formato: text/html
EN
Relevância na Pesquisa
86.04%
The western corn rootworm, Diabrotica virgifera virgifera LeConte, is one of the most economically important insect pests of corn, Zea mays L. Many different techniques have been developed for western corn rootworm host-plant resistance screening, but little has been done to compare the reliability and repeatability of these techniques. Seventeen maize cultivars were evaluated for field adult emergence, vertical pulling resistance, and field/greenhouse root feeding damage to determine the optimal method or combination of methods to more quickly reach the goal of corn rootworm resistance in corn. A rootworm host-search behavior bioassay was also conducted. Rank correlation of root damage field performance among the 17 cultivars was found between locations in both 1996 and 1997. Greenhouse root damage experiments generally did not correlate to each other or to field locations. There was no correlation in percentage reduction of pulling force in infested versus noninfested rows between 1997 paired-row pulling trials to other experiments. There was no correlation of field root damage performance in 1996 or 1997 to the 3 bioassay parameters tested: area searched, distance traveled, or number of path crossovers. It appears that the rootworm host-search behavior bioassay will not be useful in differentiating hosts within a species...

An Improved Methodology for Massive Screening of Brachiaria spp. Genotypes for Resistance to Aeneolamia varia (Homoptera: Cercopidae)

Cardona, Cesar; Miles, John W.; Sotelo, Guillermo
Fonte: Oxford University Press Publicador: Oxford University Press
Tipo: Artigo de Revista Científica Formato: text/html
EN
Relevância na Pesquisa
66.03%
Several species and genera of spittlebugs (Homoptera: Cercopidae) are economic pests of grasses in tropical America. They have the potential to cause serious losses on millions of hectares of improved pastures based on cultivars of several species of Brachiaria. Most of the available commercial cultivars of Brachiaria are susceptible to spittlebug. Resistance has been identified in several germplasm accessions and in one of the commercial cultivars, B. brizantha (A. Rich.) Stapf ‘Marandú’. Brachiaria breeding projects require reliable techniques to screen for host plant resistance in large, segregating populations. A series of experiments was conducted to improve evaluation methodology. A smaller plant growth unit, supporting a single-stem, vegetative propagule, was developed and tested. Infestation levels for both adults (6 per plant) and for nymphs (10 per plant) were established. The refinements in screening methodology increase both reliability and capacity of the screen. Infestation of smaller plant propagules saves time, space, and physical resources. It also allows clear expression of insect damage symptoms and hence permits discrimination between tolerance and antibiosis in host plant reaction. Selection can be based on both resistance mechanisms. We outline a 2-yr Brachiaria breeding cycle which incorporates the new spittlebug resistance screening methodology.

Role of Leaf Sheath Lignification and Anatomy in Resistance Against Southern Chinch Bug (Hemiptera: Blissidae) in St. Augustinegrass

Rangasamy, Murugesan; Rathinasabapathi, Bala; McAuslane, Heather J.; Cherry, Ronald H.; Nagata, Russell T.
Fonte: Oxford University Press Publicador: Oxford University Press
Tipo: Artigo de Revista Científica Formato: text/html
EN
Relevância na Pesquisa
65.86%
Southern chinch bug, Blissus insularis Barber (Hemiptera: Blissidae), is the most serious insect pest of St. Augustinegrass Stenotaphrum secundatum (Walter) Kuntze, a common lawngrass grown in southeastern U.S. states. Host plant resistance to southern chinch bug has been identified in the polyploid St. Augustinegrass‘FX-10′ and the diploid ‘Captiva’. The objective of this research was to identify possible physical mechanism(s) explaining chinch bug resistance in these cultivars. We studied the distribution of chinch bug salivary sheaths in the preferred tissue for feeding (the axillary shoot) of the two resistant cultivars and two susceptible cultivars, paired for ploidy (‘Floratam’, polyploid, and Palmetto, diploid). We also investigated the potential role of axillary shoot lignification and anatomy in chinch bug resistance. Salivary sheaths were more abundant on the outermost leaf sheath of axillary shoots of resistant cultivars compared with susceptible cultivars. In contrast, fewer salivary sheaths reached the innermost meristematic tissue in the axillary shoots of resistant St. Augustinegrass cultivars than in the two susceptible cultivars. The polyploid cultivars FX-10 and Floratam had higher total lignin in axillary shoots compared with the diploid cultivars Captiva and Palmetto. However...

Resistance of Potato Germplasm to the Potato Tuberworm (Lepidoptera: Gelechiidae)

Rondon, Silvia I.; Hane, Danny C.; Brown, Charles R.; Isabel Vales, M.; Dogramaci, Mahmut
Fonte: Oxford University Press Publicador: Oxford University Press
Tipo: Artigo de Revista Científica Formato: text/html
EN
Relevância na Pesquisa
65.87%
The evaluation of potato germplasm for resistance to potato tuberworm, Phthorimaea operculella (Zeller) (Lepidoptera: Gelechiidae), is a valuable component of integrated pest management; however, few attempts have been made to identify natural genetic tuber resistance to tuberworm on potato germplasm. The objective of this study was to screen potato germplasm with potential tuberworm resistance for tuber resistance under field and laboratory conditions. Experiments were conducted over a 2-yr period at the Hermiston Agricultural Research and Extension Center, Hermiston, OR. Of 125 germplasm that were tested in 2006, q13 were selected for further screening in 2007. These germplasm were: A0008-1TE, A97066LB, NY123, PA00N10-5, PA99N2, PA99N82, Paciencia, Q174-2, Russet Burbank, Rubi, Ranger Russet, Spunta G2, and T88-4. Tuber resistance of potato germplasm was determined based on the number of mines per tuber and the number of live larvae. Tubers of transgenic clone Spunta G2 were resistant to tuberworm damage. All other germplasm tested in this study, including Russet Burbank and Ranger Russet, were susceptible to tuberworm in the field and laboratory experiments. Incorporation of host plant resistance to tuber penetration by larvae together with appropriate cultural practices including limiting exposure time of tubers in the field may provide the best management option in the future.

Inheritance and Categories of Resistance in Wheat to Russian Wheat Aphid (Hemiptera: Aphididae) Biotype 1 and Biotype 2

Khan, S. A.; Murugan, M.; Starkey, S.; Manley, A.; Smith, C. M.
Fonte: Oxford University Press Publicador: Oxford University Press
Tipo: Artigo de Revista Científica Formato: text/html
EN
Relevância na Pesquisa
65.88%
The Russian wheat aphid, Diruaphis noxia (Kudjumov) (Hemiptera: Aphididae), is globally one of the most devastating pests of wheat, Tritium aestivum L., and barley, Hordeum vulgare L. Host plant resistance is the foundation of cereal insect pest management programs, and several D. noxia resistance (Dn) genes from wheat have been introduced in commercial cultivars of wheat to manage Russian wheat aphid (RWA). Emergence of D. noxia biotype 2 (RWA2) in Colorado has made all known Dn genes, except the Dn7 gene from rye, Secale cereale L., vulnerable and has warranted exploration for sources of resistance to RWA1 and RWA2. Here, we report antibiosis resistance to RWA1 and RWA2 identified in the wheat breeding line KS94H871. Additional experiments indicated that tolerance and antixenosis are not operating in KS94H871. Segregation studies involving F2-derived F3 families indicated that KS94H871 resistance to RWA1 is controlled by one dominant gene and one recessive gene, whereas resistance to RWA2 is controlled by only one dominant gene. This new genetic resource may serve as a good source of resistance in future breeding programs with proper understanding of the genetics of resistance.

Greenbugs: Components of Host-Plant Resistance in Sorghum

Schuster, D. J.; Starks, K. J.
Fonte: Oxford University Press Publicador: Oxford University Press
Tipo: Artigo de Revista Científica Formato: text/html
EN
Relevância na Pesquisa
65.97%
To determine the components of host plant resistance to Schizaphis gramimon (Rondani), eleven sorghum selections were compared in green house and growth chamber studies. BOK-8, the susceptible check, was preferred by the adults in free-choice tests. Some of the selections were highly nonpreferred by both apterate and alate forms. Antibiosis was also a resistant factor in some selections since there were fewer nymphs having smaller weights on some selections, and the time until reproduction started was lengthened. Tolerance measured by plant-height differences between infested and uninfested plants of each entry and by plant-injury ratings indicated that this may be the main component of PI-264453. Five of the selections (PI-229828, IS-809, Shallu Grain, PI-302178, and PI-226096) indicated comparatively high degrees of all three resistance components. Five species of the genus Sorghum showed resistance by one or more components.

Role of host-plant resistance and disease development stage on leaf photosynthetic competence of soybean rust infected leaves.

KUMUDINI, S.; GODOY, C. V.; KENNEDY, B.; PRIOR, E.; OMIELAN, J.; BOERMA, H. R.; HERSHMANN, D.
Fonte: Crop Science, Madison, v. 50, n. p. 2533-2542, nov./dec. 2010. Publicador: Crop Science, Madison, v. 50, n. p. 2533-2542, nov./dec. 2010.
Tipo: Artigo em periódico indexado (ALICE)
EN
Relevância na Pesquisa
65.98%
Host-plant resistance is known to reduce fungal growth of Phakospora pachyrhizi Syd. & P. Syd., the causal agent of soybean rust (SBR) in soybean (Glycine max L. Merr.). This disease has been shown to reduce soybean leaf photosynthesis in susceptible soybean plants. Since resistant lines have reduced fungal growth, the resistance genes may protect these plants against injury to leaf photosynthesis. The objectives of this study were to determine the impact of a host-plant resistance gene and disease developmental stage on leaf photosynthesis. Two controlled-environment studies and a field experiment were conducted using genotypes resistant and susceptible to SBR. Photosynthesis was measured at the pre- and the postsporulation disease developmental stage and its quantitative impact was calculated for the genotypes. The susceptible genotypes formed tan, sporulating lesions, and the resistant genotype formed reddish-brown (RB), nonsporulating lesions. The resistant genotype reduced disease severity (measured as relative lesion area). The negative impact of SBR on leaf photosynthesis was the same for resistant and susceptible genotypes (at equivalent disease severity levels), and the pre- and postsporulation disease development stages. Since the resistant genotype formed significantly lower lesion area...

Interaction of Anthonomus grandis and cotton genotypes: biological and behavioral responses

SILVA, J. B.; SILVA-TORRES, C. S. A.; MORAES, M. C. B.; TORRES, J. B.; LAUMANN, R. A.; BORGES, M.
Fonte: Entomologia Experimentalis et Applicata, v. 156, p. 238?253, 2015. Publicador: Entomologia Experimentalis et Applicata, v. 156, p. 238?253, 2015.
Tipo: Artigo em periódico indexado (ALICE)
EN
Relevância na Pesquisa
65.92%
The boll weevil, Anthonomus grandis Boheman (Coleoptera: Curculionidae), is a key pest of cotton, Gossypium hirsutum L. (Malvaceae). Knowledge about boll weevil feeding and oviposition behavior and its response to plant volatiles can underpin our understanding of host plant resistance, and contribute to improved monitoring and mass capture of this pest. Boll weevil oviposition preference and immature development in four cotton genotypes (CNPA TB90, TB85, TB15, and BRS Rubi) were investigated in the laboratory and greenhouse. Volatile organic compounds (VOCs) produced by TB90 and Rubi genotypes were obtained from herbivore-damaged and undamaged control plants at two phenological stages ? vegetative (prior to squaring) and reproductive (during squaring) ? and four collection times ? 24, 48, 72, and 96 h following herbivore damage. The boll weevil exhibited similar feeding and oviposition behavior across the four tested cotton genotypes. The chemical profiles of herbivore-damaged plants of both genotypes across the two phenological stages were qualitatively similar, but differed in the amount of volatiles produced. Boll weevil response to VOC extracts was studied using a Y-tube olfactometer. The boll weevil exhibited similar feeding and oviposition behavior at the four tested cotton genotypes...

Resistance induction in wheat plants by silicon and aphids

Gomes,Flávia Batista; Moraes,Jair Campos de; Santos,Custódio Donizete dos; Goussain,Márcio Marcos
Fonte: São Paulo - Escola Superior de Agricultura "Luiz de Queiroz" Publicador: São Paulo - Escola Superior de Agricultura "Luiz de Queiroz"
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/12/2005 EN
Relevância na Pesquisa
65.92%
The pest greenbug Schizaphis graminum (Rondani) (Hemiptera: Aphididae) stands out among the factors limiting Brazilian wheat production. Chemical control is predominant in aphid management making the production dependent on insecticides. The effect of silicon and previous infestation with aphids on the induction of resistance to the greenbug was evaluated in wheat plants. Treatments consisted of control; fertilization with calcium silicate; plant infestation with aphids; fertilization with calcium silicate + plant infestation with aphids. A free-choice preference test was performed 35 days after seedling emergence; the aphid's intrinsic rate of population increase (r m) was also determined, and the activities of three enzymes (peroxidase, polyphenoloxidase, and phenylalanine ammonia-lyase) involved in plant defense were quantified. Silicon fertilization and the previous infestation with aphids induced wheat plant resistance to the greenbug.

Indução de resistência em plantas de trigo por silíco e pulgões; Resistance induction in wheat plants by silicon and aphids

Gomes, Flávia Batista; Moraes, Jair Campos de; Santos, Custódio Donizete dos; Goussain, Márcio Marcos
Fonte: Universidade de São Paulo. Escola Superior de Agricultura Luiz de Queiroz Publicador: Universidade de São Paulo. Escola Superior de Agricultura Luiz de Queiroz
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; ; ; ; ; Formato: application/pdf
Publicado em 01/12/2005 ENG
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65.92%
Dentre os fatores limitantes da produção tritícola brasileira está o ataque de insetos-praga, podendo-se destacar o pulgão-das-gramíneas Schizaphis graminum (Rondani) (Hemiptera: Aphididae). O controle químico é predominante no manejo desse pulgão, tornando a produção dependente do uso de inseticidas. Este trabalho avalia o efeito do silício e da infestação prévia com pulgões na indução de resistência ao pulgão-das-gramíneas em plantas de trigo. Os tratamentos foram: testemunha; adubação com silicato de cálcio; infestação das plantas com pulgões; adubação com silicato de cálcio + infestação das plantas com pulgões. Trinta e cinco dias após emergência das plântulas foi realizado teste de preferência com chance de escolha; determinação da taxa de crescimento da população do pulgão (r m) e quantificação da atividade de três enzimas envolvidas na defesa das plantas: peroxidase, polifenoloxidase e fenilalanina amônia-liase. A adubação silicatada e a infestação prévia com pulgões induzem resistência em plantas de trigo ao pulgão-das-gramíneas.; The pest greenbug Schizaphis graminum (Rondani) (Hemiptera: Aphididae) stands out among the factors limiting Brazilian wheat production. Chemical control is predominant in aphid management making the production dependent on insecticides. The effect of silicon and previous infestation with aphids on the induction of resistance to the greenbug was evaluated in wheat plants. Treatments consisted of control; fertilization with calcium silicate; plant infestation with aphids; fertilization with calcium silicate + plant infestation with aphids. A free-choice preference test was performed 35 days after seedling emergence; the aphid's intrinsic rate of population increase (r m) was also determined...

Nematode pests threatening soybean production in South Africa, with reference to Meloidogyne

Fourie,Hendrika; de Waele,Dirk; Mc Donald,Alexander H.; Mienie,Charlotte; Marais,Mariette; de Beer,Annelie
Fonte: South African Journal of Science Publicador: South African Journal of Science
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/10/2015 EN
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The area planted to soybean in South Africa has increased by 54% since the 2009 growing season, mainly as a result of the increasing demand for protein-rich food and fodder sources. Moreover, the introduction of advanced technology, namely the availability of genetically modified herbicide tolerant soybean cultivars also contributed towards increased soybean production. The omnipresence of plant-parasitic nematodes in local agricultural soils, however, poses a threat to the sustainable expansion and production of soybean and other rotation crops. Meloidogyne incognita and M. javanica are the predominant nematode pests in local soybean production areas and those where other grain-, legume- and/or vegetable crops are grown. The lack of registered nematicides for soybean locally, crop production systems that are conducive to nematode pest build-ups as well as the limited availability of genetic host plant resistance to root-knot nematode pests, complicate their management. Research aimed at various aspects related to soybean-nematode research, namely, audits of nematode assemblages associated with the crop, identification of genetic host plant resistance in soybean germplasm to M. incognita and M. javanica, the use of molecular markers that are linked to such genetic resistance traits as well as agronomic performance of pre-released cultivars that can be valuable to producers and the industry are accentuated in this review. Evaluation of synthetically-derived as well as biological-control agents are also discussed as complementary management tactics. It is important that lessons learned through extensive research on soybean-nematode interactions in South Africa be shared with researchers and industries in other countries as they might experience or expect similar problems and/or challenges.