Monitoring <i>Chrysaora hysoscella</i> (Cnidaria, Scyphozoa) in the Belgian part of the North Sea using eDNA

The use of Environmental DNA (eDNA) in monitoring ecosystems is now gaining attention in the field of research. The technique has shown a snapshot of the organisms present in the ecosystem being studied. Recent studies have demonstrated that the distribution and biomass of aquatic organisms can be estimated through detection and quantification of eDNA samples in the studied ecosystem. The approach is very rarely used in studying the detection and distribution of jellyfish in marine ecosystem. To investigate the technique’s applicability in detecting and monitoring marine gelatinous zooplankton, eDNA was used to monitory the compass jellyfish (Chrysaora hysoscella) in the southern North Sea. eDNA samples were collected from the surface water of the nine studied stations in the Belgian part of the North Sea (BPNS) from 2014 to 2016. In this study, eDNA samples from October 2014, March, May, August and October 2015, January, March, May and August 2016 were extracted using CTAB. eDNA extracts were run in a qPCR for C. hysoscella eDNA detection and quantification.This study detected C. hysoscella eDNA in the BPNS across the sampling months with a reduction in the frequency of detection in 2016. The target eDNA was found to be more common in Oostende then in Nieuwpoort and least in Zeebrugge stations. C. hysoscella eDNA was common and abundant in offshore stations and least in the shoreline stations. Peaks of eDNA abundance were recorded in spring, summer and autumn periods (October 2014, March, May and August 2016, March and August 2016). The recorded eDNA abundance was found to be not correlated with temperature (p = 0.4254). The results also revealed that the abundance of C. hysoscella eDNA somehow exhibited temporal and spatial variations. The results of this study imply that eDNA approach can be used to study the presence, patterns of distribution and the estimates of C. hysoscella biomass in the BPNS. This study confirms the broad potential of eDNA method in surveying ecosystems. The eDNA protocol used in the present study can be developed further to monitor jellyfish population in the BPNS obtaining a more detailed estimates of jellyfish abundance and distribution

State machine design of functional circuit board testing

Current testing of complex Surface Mount Technology (SMT) circuit boards on the In-Circuit testers (ICT) have a number of limitations. The circuit boards as they become denser and more complex, do not have all the circuit nodes accessible to the standard bed of nails type testers. An emphasis to develop innovative methods to functionally test these advanced circuits boards while limiting expense and ensuring quality is necessary. A method to perform a system test in the ICT environment utilizes on - board and system diagnostics, without the hardware of an additional tester. A universal Dynamic Test Interface (DTI) and a small amount of custom circuitry allows facilitation of the test within the ICT fixture. The test is controlled and integrated with the ICT, by use of assembly language software. A wide variety of circuit boards can be fully and functionally tested by this method, ensuring a high quality of deliverable product at minimal expense.Includes bibliographical references (pages 48-49)California State University, Northridge. Department of Engineering

Delimiting the polymorphic congeners of the genus Oerstedia Quatrefages, 1864 (Nemertea, Hoplonemertea), and descriptions of three new species from the Northwest Pacific

Three new species of the monostiliferous hoplonemertean genus Oerstedia Quatrefages, 1864, are herein described using morphological and molecular data—Oerstedia pseudoculata sp. nov., from Akkeshi Bay and Oshoro Bay, Hokkaido, Japan, and from Aniwa Bay, Sakhalin, Russia; Oerstedia rugosa sp. nov. from Sagami Bay, Misaki, Kanagawa, Japan, and Van Phong Bay, Vietnam; and Oerstedia viridifusca sp. nov. from Manazuru, Kanagawa, Japan. As to the external morphology, O. pseudoculata sp. nov. can be differentiated from O. oculata only by its bright-orange ocelli visible on both sides of the head, and a proboscis pore opening at the ventral tip of the head. These two sister species repeat each other’s color patterns, a phenomenon that can be explained by Vavilov’s law of homologous series. Oerstedia rugosa sp. nov. can be identified by its carmine or deep-red to brownish-red body with several longitudinal, intertwined white lines or wrinkles running from the head to the posterior body, and by 17–23 vaguely bordered white bands composed of variedly sized dots encircling the body, arranged at irregular intervals. Oerstedia viridifusca sp. nov. can be distinguished from other Oerstedia by (i) the entire body flecked with minute greenish-brown dots, especially densely on the anterior portion of the dorsal surface, but sparsely on the posterior half of the ventral surface; (ii) a collar-like portion encircling the body along the posterior cephalic furrow where the greenish-brown dots are absent; (iii) the anterolateral edges of the head lacking the greenish-brown dots; and (iv) the ocelli being brownish-orange in color. Oerstedia phoresiae (Kulikova, 1987) is reported for the first time from Japan, in addition to its previous distribution record in Russia and in South Korea. Phylogenetic analyses based on the 16S, 18S, 28S ribosomal RNA, cytochrome c oxidase subunit I, and histone H3 genes show that the new species are true congeners of the genus Oerstedia with O. pseudoculata sp. nov. and O. viridifusca sp. nov. nested within the clade Paroerstediella whereas O. rugosa sp. nov. in the clade Oerstedia. This taxonomic work emphasizes the importance of DNA barcode sequence in the taxonomy and systematics of the polymorphic congeners of the genus Oerstedia

Acarofauna associated to papaya orchards in Veracruz, Mexico

Productores agrícolas en México recientemente notaron un fuerte incremento en las infestaciones de ácaros en las huertas de papayo (Carica papaya L. 1753). Se elaboró una lista de las especies de ácaros asociados con hojas de papayo para determinar las especies responsables de las altas infestaciones y para identificar a los ácaros depredadores. Los ácaros fueron colectados de tres estratos (alto, medio y bajo) en siete muncipios del centro del estado de Veracruz. Las hojas fueron procesadas por lavado y tamizado. Las especies identificadas incluyeron cuatro tetraníquidos: Eotetranychus lewisi (McGregor 1943), Eutetranychus banksi (McGregor 1914), Tetranychus merganser Boudreaux 1954 y Tetranychus urticae Koch 1836; tres fitoseidos: Euseius hibisci (Chant 1959), Galendromus helveolus (Chant 1959) y Phytoseiulus macropilis (Banks 1904), donde las dos primeras especies fueron las más abundantes. El ácaro eriófido errante Calacarus citrifolii Keifer 1955 fue colectado en tres municipios, en el estrato bajo. El ácaro blanco, Polyphagotarsonemus latus (Banks 1904), y el ácaro carmín, Tetranychus cinnabarinus (Boisduval 1867), no fueron colectados, aunque estas dos especies fueron registradas previamente en esta área. Ninguno de los fitoseidos encontrados puede ser considerado de reciente establecimiento en el área; se discute su potencial como agentes de control biológico

Determination of enantiomeric compositions by transient absorption spectroscopy using proteins as chiral selectors

Financial support from the MEC (Grant CTQ2007-67010 and predoctoral fellowship to C.J.B. and I. V.), from the Carlos III Institute of Health (Grant RIRAAF, RETICS program) and from the Generalitat Valenciana (Prometeo Program) is gratefully acknowledged.Vayá Pérez, I.; Bueno Alejo, CJ.; Jiménez Molero, MC.; Miranda Alonso, MÁ. (2008). Determination of enantiomeric compositions by transient absorption spectroscopy using proteins as chiral selectors. Chemistry - A European Journal. 14(36):11284-11287. https://doi.org/10.1002/chem.200801657S11284112871436Finn, M. G. (2002). Emerging methods for the rapid determination of enantiomeric excess. Chirality, 14(7), 534-540. doi:10.1002/chir.10101Maier, N. M., Franco, P., & Lindner, W. (2001). Separation of enantiomers: needs, challenges, perspectives. Journal of Chromatography A, 906(1-2), 3-33. doi:10.1016/s0021-9673(00)00532-xPirkle, W. H., & Finn, J. M. (1981). Chiral high-pressure liquid chromatographic stationary phases. 3. 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Measurement of Enantiomeric Excess by Kinetic Resolution and Mass Spectrometry. Angewandte Chemie International Edition, 38(12), 1755-1758. doi:10.1002/(sici)1521-3773(19990614)38:123.0.co;2-qReetz, M. T., Becker, M. H., Klein, H.-W., & Stöckigt, D. (1999). Eine Methode zum High-Throughput-Screening von enantioselektiven Katalysatoren. Angewandte Chemie, 111(12), 1872-1875. doi:10.1002/(sici)1521-3757(19990614)111:123.0.co;2-gReetz, M. T., Becker, M. H., Klein, H.-W., & Stöckigt, D. (1999). A Method for High-Throughput Screening of Enantioselective Catalysts. Angewandte Chemie International Edition, 38(12), 1758-1761. doi:10.1002/(sici)1521-3773(19990614)38:123.0.co;2-8Markert, C., & Pfaltz, A. (2004). Screening of Chiral Catalysts and Catalyst Mixtures by Mass Spectrometric Monitoring of Catalytic Intermediates. Angewandte Chemie, 116(19), 2552-2554. doi:10.1002/ange.200453844Markert, C., & Pfaltz, A. (2004). Screening of Chiral Catalysts and Catalyst Mixtures by Mass Spectrometric Monitoring of Catalytic Intermediates. Angewandte Chemie International Edition, 43(19), 2498-2500. doi:10.1002/anie.200453844Reetz, M. T., Kühling, K. M., Deege, A., Hinrichs, H., & Belder, D. (2000). Super-Hochdurchsatz-Screening von enantioselektiven Katalysatoren mittels parallelisierter Kapillarelektrophorese. Angewandte Chemie, 112(21), 4049-4052. doi:10.1002/1521-3757(20001103)112:213.0.co;2-nReetz, M. T., Kühling, K. M., Deege, A., Hinrichs, H., & Belder, D. (2000). Super-High-Throughput Screening of Enantioselective Catalysts by Using Capillary Array Electrophoresis. Angewandte Chemie, 39(21), 3891-3893. doi:10.1002/1521-3773(20001103)39:213.0.co;2-1Abato, P., & Seto, C. T. (2001). EMDee:  An Enzymatic Method for Determining Enantiomeric Excess. Journal of the American Chemical Society, 123(37), 9206-9207. doi:10.1021/ja016177qVan Delden, R. A., & Feringa, B. L. (2001). Color Indicators of Molecular Chirality Based on Doped Liquid Crystals. Angewandte Chemie, 113(17), 3298-3300. doi:10.1002/1521-3757(20010903)113:173.0.co;2-eVan Delden, R. A., & Feringa, B. L. (2001). Color Indicators of Molecular Chirality Based on Doped Liquid Crystals. Angewandte Chemie International Edition, 40(17), 3198-3200. doi:10.1002/1521-3773(20010903)40:173.0.co;2-iTaran, F., Gauchet, C., Mohar, B., Meunier, S., Valleix, A., Renard, P. Y., … Mioskowski, C. (2002). High-Throughput Screening of Enantioselective Catalysts by Immunoassay. Angewandte Chemie, 114(1), 132-135. doi:10.1002/1521-3757(20020104)114:13.0.co;2-dTaran, F., Gauchet, C., Mohar, B., Meunier, S., Valleix, A., Renard, P. Y., … Mioskowski, C. (2002). High-Throughput Screening of Enantioselective Catalysts by Immunoassay. Angewandte Chemie International Edition, 41(1), 124-127. doi:10.1002/1521-3773(20020104)41:13.0.co;2-rLi, Z., Bütikofer, L., & Witholt, B. (2004). High-Throughput Measurement of the Enantiomeric Excess of Chiral Alcohols by Using Two Enzymes. Angewandte Chemie, 116(13), 1730-1734. doi:10.1002/ange.200353055Li, Z., Bütikofer, L., & Witholt, B. (2004). High-Throughput Measurement of the Enantiomeric Excess of Chiral Alcohols by Using Two Enzymes. Angewandte Chemie International Edition, 43(13), 1698-1702. doi:10.1002/anie.200353055Eelkema, R., van Delden, R. A., & Feringa, B. L. (2004). Direct Visual Detection of the Stereoselectivity of a Catalytic Reaction. Angewandte Chemie, 116(38), 5123-5126. doi:10.1002/ange.200460822Eelkema, R., van Delden, R. A., & Feringa, B. L. (2004). Direct Visual Detection of the Stereoselectivity of a Catalytic Reaction. Angewandte Chemie International Edition, 43(38), 5013-5016. doi:10.1002/anie.200460822Dey, S., Karukurichi, K. R., Shen, W., & Berkowitz, D. B. (2005). Double-Cuvette ISES:  In Situ Estimation of Enantioselectivity and Relative Rate for Catalyst Screening. Journal of the American Chemical Society, 127(24), 8610-8611. doi:10.1021/ja052010bMei, X., & Wolf, C. (2006). Determination of Enantiomeric Excess and Concentration of Unprotected Amino Acids, Amines, Amino Alcohols, and Carboxylic Acids by Competitive Binding Assays with a Chiral Scandium Complex. Journal of the American Chemical Society, 128(41), 13326-13327. doi:10.1021/ja0636486Reetz, M. T., Becker, M. H., Kühling, K. M., & Holzwarth, A. (1998). Zeitaufgelöste IR-thermographische Detektion und Screening von enantioselektiven katalytischen Reaktionen. Angewandte Chemie, 110(19), 2792-2795. doi:10.1002/(sici)1521-3757(19981002)110:193.0.co;2-2Reetz, M. T., Becker, M. H., Kühling, K. M., & Holzwarth, A. (1998). Time-Resolved IR-Thermographic Detection and Screening of Enantioselectivity in Catalytic Reactions. Angewandte Chemie International Edition, 37(19), 2647-2650. doi:10.1002/(sici)1521-3773(19981016)37:193.0.co;2-iDing, K., Ishii, A., & Mikami, K. (1999). Super-High-Throughput-Screening chiraler Liganden und Aktivatoren: asymmetrische Aktivierung chiraler Diol-Zink-Katalysatoren durch chirale Stickstoffaktivatoren für die enantioselektive Addition von Diethylzink an Aldehyde. Angewandte Chemie, 111(4), 519-523. doi:10.1002/(sici)1521-3757(19990215)111:43.0.co;2-6Ding, K., Ishii, A., & Mikami, K. (1999). Super High Throughput Screening (SHTS) of Chiral Ligands and Activators: Asymmetric Activation of Chiral Diol-Zinc Catalysts by Chiral Nitrogen Activators for the Enantioselective Addition of Diethylzinc to Aldehydes. Angewandte Chemie International Edition, 38(4), 497-501. doi:10.1002/(sici)1521-3773(19990215)38:43.0.co;2-gYannoni, C. S. (1982). High-resolution NMR in solids: the CPMAS experiment. Accounts of Chemical Research, 15(7), 201-208. doi:10.1021/ar00079a003Tekely, P., Gardiennet, C., Potrzebowski, M. J., Sebald, A., Reichert, D., & Luz, Z. (2002). Probing molecular geometry of solids by nuclear magnetic resonance spin exchange at the n=0 rotational-resonance condition. The Journal of Chemical Physics, 116(17), 7607-7616. doi:10.1063/1.1465416Potrzebowski, M. J., Tadeusiak, E., Misiura, K., Ciesielski, W., Bujacz, G., & Tekely, P. (2002). A New Method for Distinguishing between Enantiomers and Racemates and Assignment of Enantiomeric Purity by Means of Solid-State NMR. Examples from Oxazaphosphorinanes. Chemistry - A European Journal, 8(21), 5007-5011. doi:10.1002/1521-3765(20021104)8:213.0.co;2-bEvans, M. A., & Morken, J. P. (2002). Isotopically Chiral Probes for in Situ High-Throughput Asymmetric Reaction Analysis. Journal of the American Chemical Society, 124(31), 9020-9021. doi:10.1021/ja026703tJames, T. D., Samankumara Sandanayake, K. R. A., & Shinkai, S. (1995). Chiral discrimination of monosaccharides using a fluorescent molecular sensor. Nature, 374(6520), 345-347. doi:10.1038/374345a0(s. f.). doi:10.1021/ja984139Beer, G., Daub, J., & Rurack, K. (2001). Chiral discrimination with a fluorescent boron–dipyrromethene dye. Chemical Communications, (12), 1138-1139. doi:10.1039/b102376bZhao, J., Fyles, T. M., & James, T. D. (2004). Chiral Binol–Bisboronic Acid as Fluorescence Sensor for Sugar Acids. Angewandte Chemie, 116(26), 3543-3546. doi:10.1002/ange.200454033Zhao, J., Fyles, T. M., & James, T. D. (2004). Chiral Binol–Bisboronic Acid as Fluorescence Sensor for Sugar Acids. Angewandte Chemie International Edition, 43(26), 3461-3464. doi:10.1002/anie.200454033Pu, L. (2004). Fluorescence of Organic Molecules in Chiral Recognition. Chemical Reviews, 104(3), 1687-1716. doi:10.1021/cr030052hLi, Z.-B., Lin, J., Qin, Y.-C., & Pu, L. (2005). Enantioselective Fluorescent Recognition of a Soluble «Supported» Chiral Acid:  Toward a New Method for Chiral Catalyst Screening. Organic Letters, 7(16), 3441-3444. doi:10.1021/ol0510163Matsushita, M., Yoshida, K., Yamamoto, N., Wirsching, P., Lerner, R. A., & Janda, K. D. (2003). High-Throughput Screening by Using a Blue-Fluorescent Antibody Sensor. Angewandte Chemie, 115(48), 6166-6169. doi:10.1002/ange.200352793Matsushita, M., Yoshida, K., Yamamoto, N., Wirsching, P., Lerner, R. A., & Janda, K. D. (2003). High-Throughput Screening by Using a Blue-Fluorescent Antibody Sensor. Angewandte Chemie International Edition, 42(48), 5984-5987. doi:10.1002/anie.200352793Hamberg, A., Lundgren, S., Penhoat, M., Moberg, C., & Hult, K. (2006). High-Throughput Enzymatic Method for Enantiomeric Excess Determination of O-Acetylated Cyanohydrins. Journal of the American Chemical Society, 128(7), 2234-2235. doi:10.1021/ja058474rBusch, K. W., Swamidoss, I. M., Fakayode, S. O., & Busch, M. A. (2003). Determination of the Enantiomeric Composition of Guest Molecules by Chemometric Analysis of the UV−Visible Spectra of Cyclodextrin Guest−Host Complexes. Journal of the American Chemical Society, 125(7), 1690-1691. doi:10.1021/ja025947aFakayode, S. O., Busch, M. A., Bellert, D. J., & Busch, K. W. (2005). Determination of the enantiomeric composition of phenylalanine samples by chemometric analysis of the fluorescence spectra of cyclodextrin guest–host complexes. The Analyst, 130(2), 233-241. doi:10.1039/b405478dABE, Y., YASUOKA, S., SHOJI, T., SUGATA, S., HATTORI, K., IWATA, K., & SUZUKI, H. (2002). Peculiar Chiral Discrimination of Bovine Serum Albumin to (.+-.)-N-Dansyl-norleucine. Analytical Sciences, 18(7), 823-825. doi:10.2116/analsci.18.823Hamblin, J., Abboyi, N., & Lowe, M. P. (2005). A binaphthyl-containing Eu(iii) complex and its interaction with human serum albumin: a luminescence study. Chemical Communications, (5), 657. doi:10.1039/b415464aSingh, S. S., & Mehta, J. (2006). Measurement of drug–protein binding by immobilized human serum albumin-HPLC and comparison with ultrafiltration. Journal of Chromatography B, 834(1-2), 108-116. doi:10.1016/j.jchromb.2006.02.053Hödl, H., Koidl, J., Schmid, M. G., & Gübitz, G. (2006). Chiral resolution of tryptophan derivatives by CE using canine serum albumin and bovine serum albumin as chiral selectors. ELECTROPHORESIS, 27(23), 4755-4762. doi:10.1002/elps.200600425Martínez-Gómez, M. A., Sagrado, S., Villanueva-Camañas, R. M., & Medina-Hernández, M. J. (2007). Enantioseparation of phenotiazines by affinity electrokinetic chromatography using human serum albumin as chiral selector. Analytica Chimica Acta, 582(2), 223-228. doi:10.1016/j.aca.2006.09.036Jiménez, M. C., Miranda, M. A., & Vayá, I. (2005). Triplet Excited States as Chiral Reporters for the Binding of Drugs to Transport Proteins. Journal of the American Chemical Society, 127(29), 10134-10135. doi:10.1021/ja0514489Vayá, I., Bueno, C. J., Jiménez, M. C., & Miranda, M. A. (2006). Use of Triplet Excited States for the Study of Drug Binding to Human and Bovine Serum Albumins. ChemMedChem, 1(9), 1015-1020. doi:10.1002/cmdc.200600061Bohne, C., Barra, M., Boch, R., Abuin, E. B., & Scaiano, J. C. (1992). Excited triplet states as probes in organized systems. An overview of recent results. Journal of Photochemistry and Photobiology A: Chemistry, 65(1-2), 249-265. doi:10.1016/1010-6030(92)85050-5Jiménez, M. C., Miranda, M. A., Tormos, R., & Vayá, I. (2004). Characterisation of the lowest singlet and triplet excited states of S-flurbiprofen. Photochem. Photobiol. Sci., 3(11-12), 1038-1041. doi:10.1039/b408530

Manejo diversificado del agroecosistema “Moyola” Jalcomulco, Veracruz

La visión holística de los Agroecosistemas (AE) implica comprender las necesidades del agricultor y su relación con la biota, su producción y el ambiente. Esta investigación tuvo como objetivo caracterizar el AE “Moyola”, desde la percepción del productor (Aspecto socio-cultural). Se describe el diseño espacial y temporal de los cultivos; la información de campo se documenta con bibliografía, se calculan los índices de diversidad de Margalef, Shanon-Wiener y Simpson en las áreas de cultivo de lima persa y área conservada (Aspecto ambiental); se hace el análisis de beneficio-costo del cultivo comercial (lima persa) con una proyección a 5 años (Aspecto económico). El AE posee una superficie de 35 ha, tienen una Unidad de Manejo Ambiental (UMA). En el 2018, el agricultor estableció diversos cultivos aledaños a la UMA para mejorar sus ingresos y obtener alimentos; considerando la orografía para establecer las zonas de los cultivos. En la meseta establece una hectárea de lima persa (Citrus latifolia Tan.), se intercala cacahuate (Arachis hypogaea L.), y se conservan los árboles de guaje (Leucaena leucacephala Lam.). En otro sitio, siembra maíz negro criollo (Zea mays L.) y en las laderas planta guanábana (Anonna muricata L.) intercalada con calabaza (Curcubita sp. Huber) y cempazúchil (Tagetes erecta L.); también conserva dos áreas de mango manila y una de tocotín (Mangifera indica L.) estas acciones favorecen la biodiversidad de cultivos. Para resolver la limitante de agua, construye una olla de captación de lluvia. De acuerdo con los índices de diversidad el área de cultivo de lima persa es menos diversa que el área conservada (UMA); las fuentes de guano que obtiene de su predio son una alternativa como abono para los cultivos. El análisis económico del cultivo lima persa muestra que será rentable, con ello se crea una fuente de empleo y se favorece el arraigo y bienestar del agricultor. De acuerdo con el manejo, se considera que el AE “Moyola” está en un proceso de transición hacia un enfoque sustentable

Rentabilidad de la reprodución de enemigos naturales de ácaros del papayo (carica papaya l.)

The papaya tree production in the central zone of the state of Veracruz, México, under intensive management, is highly profitable. The crop presents high populations of spider mites, commonly controlled with acaricides. However, this practice contaminates the environment, leaves residues in the fruit, causes poisoning of applicators and promotes the fast development of resistance to pest-control substances in the acari. An effective biological control of the pest can be achieved with predatory mites, massively produced. Therefore, the technical and economic viability of establishing a Center for Massive Reproduction of Phytoseiulus persimilis in the central area of Veracruz was evaluated. The internal rate of return (IRR), the net presen value (NPV) and the benefit/cost (B/C) were calculated in a horizon of five years, with three variations of price of the product per hectare: (MX) $1,000,$1,250 and $1,500. The opinion of producers was requested through a survey regarding the product that the Center would generate. The project shows acceptable profitability, with IRR values of 41.5, 115.6 and 187.2$411,368, $1’633,913 and$2’837,815, for the three prices of the product; and B/C relation of 1.01 in the first year with the lowest price of the product, up to 1.83 with the highest price obtained on the fifth year. The main competition in the region is the sale of acaricides such as dicofol, abamectin, fenbutatin oxide and imidacloprid. Of the producers, 61.4 % are willing to use predatory mites at a cost of $1,000 per hectare. As this product cannot be stored for long periods, the success lies in a production coordinated with groups of producers

Dinámica poblacional de ácaros de las familias Tetranychidae y Phytoseiidae asociados al papayo (Carica papaya L., 1753)

Since the pesticide use has augmented in papaya (Carica papaya L., 1753), phytophagous mite populations have increased, because of the unbalance in populations, causing considerable damage. Thus, the population dynamics and the space-temporary correlation between phytophagous and predatory mites were determined in a papaya agroecosystem in Manlio F. Altamirano, Veracruz, Mexico, with conventional management including pesticides and fertilizers. Collections of three leaves per plant were performed (high, middle and low strata, one leaf each one) in 20 plants, in nine samplings from May 2007 to September 2008. Eotetranychus lewisi (McGregor, 1943) was the most abundant species in all three strata, followed by Eutetranychus banksi (McGregor, 1914) that had major populations in the low and middle strata. The generalist predator Euseius hibisci (Chant, 1959) and the tetranychid-specialized predator Galendromus helveolus (Chant, 1959) were found. Two synchronic population peaks between the group of predatory and phytophagous mite species were found. Positive correlations (r2 from 0.5 to 0.6) between populations of phytophagous and predatory mites were found. Mean temperatures above 30 °C and monthly-accumulated rain above 200 mm caused the decline of E. banksi. Based on the above data, we recommend mite sampling to begin two months from transplant, since favorable environmental conditions for the development of phytophagous mites are present in the Central zone of the State of Veracruz.En el cultivo de papayo (Carica papaya L., 1753), los ácaros fitófagos se han incrementado como resultado de un desbalance en las poblaciones por el uso excesivo de plaguicidas. Dentro de los programas de manejo integrado de plagas, es importante conocer los factores que afectan la densidad poblacional de éstas. Por ello se buscó determinar la correlación espacio temporal de ácaros fitófagos y depredadores en el cultivo de papayo en Manlio F. Altamirano, Veracruz, México. Se utilizó una huerta con manejo convencional, que incluyó la aplicación de fertilizantes y plaguicidas. Se realizaron muestreos de los ácaros en hojas colectadas en los estratos alto, medio y bajo de cada planta, una por estrato, en un total de 20 plantas. Se realizaron nueve muestreos de mayo 2007 a septiembre 2008. Eoetranychus lewisi (McGregor, 1943) fue la especie más abundante en los tres estratos, seguida de Eutetranychus banksi (McGregor, 1914), que tuvo sus mayores poblaciones en los estratos bajo y medio. Se encontró a Euseius hibisci (Chant, 1959), ácaro depredador generalista, y a Galendromus helveolus (Chant, 1959), ácaro depredador especializado en alimentarse de tetraníquidos. Se presentaron dos picos poblacionales sincrónicos entre los grupos de especies de ácaros fitófagos y depredadores. Se mostraron correlaciones positivas (r2 de 0.5 a 0.6) entre las poblaciones de ácaros fitófagos y depredadores. Temperaturas medias superiores a 30 °C y lluvia mensual acumulada superior a 200 mm abatieron las poblaciones de E. banksi. Se recomienda iniciar el muestreo de ácaros desde dos meses después del trasplante, ya que en la zona Centro del estado de Veracruz existen condiciones ambientales favorables para su desarrollo