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that study, the assemblage was comprised by F. aerea (46%), Ar. chilensis (15%), C. viridis (12%), M. cyaneus (7%) and C. vagans (5%). In our study, the numerically dominant species were F. nebroides (45%), All. chilensis (20%), Ar. chilensis (13%), F. aerea (11%) and C. chilensis (6%). Spiders belonging to Lycosidae and Gnaphosidae were represented in the captures, which are active wanderers and expected to be (over)represented in pitfall catches (Young and Edwards, 1990). Lycosid spiders are dominant in many agroecosystems, including Hungarian arable fields (Samu and Szinetár, 2000), soybean and mungbean in Australia (Pearce et al., 2004), blueberry in USA (Maloney, 2002) and many others (Marshall et al., 2002). Many lycosid species have been named agrobiont (sensu Luczak, 1979) based on their abundance and synchronization with crops. In contrast, the Gnaphosidae often represented low proportions of total catches compared with lycosids and other families in surveys conducted in other agroecosystems (Samu and Szinetár, 2002; Pearce et al., 2004; Maloney, 2002), while that in our study, Gnaphosidae was as well represented as Lycosidae, from a numerical point of view, differing from the studies cited above. Nevertheless, if biomass is considered, lycosid spiders captured in our pitfall traps represented a higher proportion because they are several times heavier than gnaphosid spiders. Response to treatments. Carabidae. Previous research have shown contrasting responses of ground predators to different pest management programs (O’Neal et al., 2005). In general, when synthetic pyrethroids like lambda-cyhalothrin are sprayed, in many cases the ground beetles are decreased, but usually they recover into 2-3 weeks (Prasifka et al., 2005; White et al., 1990). Indeed, some increases after lamba-cyhalothrin spray have been reported (Volkmar et al., 1996). In our study, negative effects of lambda-cyhalothrin in activity density of predators were detected up to 60 days after spraying. In carabid species, acute toxicity of lambda-cyhalothrin was not evident immediately after spraying, except for F. nebroides. This result must be interpreted with caution, because the catches of Ar. chilensis, C. chilensis, F. aerea and All. chilensis were very low at mid October. Therefore, the absence of active populations of beetles could be a better 59
explanation than no toxicity of the insecticide, considering significant effects of lambda- cyhalothrin were detected twice in the following sampling dates and that lambda- cyhalothrin toxicity to carabids is well documented in literature (Huusela-Veistola, 1996; Koss et al., 2005; Prasifka et al., 2005; White et al., 1990), though the response is always species-specific. F. nebroides showed a consistent response across the study. Activity density in the lambda- cyhalothrin plots was lower than control in the three post sampling dates, although the differences were significant at α= 0.05 only at the beginning and at the end of the sampling period, while the response at the intermediate sampling date was not statistically significant (p=0.29). Other carabids with comparable body size to F. nebroides can move several meters per day (Thacker and Dixon, 1996), but insecticide plots did not recover the pre- treatment populations levels at any sampling date. The negative effect of lambda-cyhalothrin on F. aerea population was evident two months after spray, but not one month after spraying. Absolute numbers increased with time in all treatments, but the increase was much more marked in the control plots than in insecticide plots, in the last sampling date. This species overwinters as adult, thus the increase should be attributed to adults moving from no treated areas to plots and not to new cohorts of adults from larvae that complete their cycle. The absence of barriers, the presence of migrant sources and the plot size would have facilitated (or at least no make more difficult) the re-colonization of treated plots by F. nebroides and F. aerea. The reasons why the re-colonization was not accomplished as expected are not clear. If the insecticide had persisted in the treated plots, direct mortality or repellence could be acted on beetles, but lambda-cyhalothrin has been reported to persist less than 2 weeks in field (Hill and Inaba, 1991; Mathirajan et al., 2000). In addition, lambda-cyhalothrin decreases when temperature increases (Huusela-Veistola, 1996) and temperature at November-December in the region (late spring and early summer) are typically higher than October (mid spring). Several authors have reported that carabids do control lepidopteran pests (French et al. 2004; Frank and Shrewsbury, 2004; Toft and Bilde, 2002). The carabid species active at the sampling period likely would not be predators of Dalaca sp. because of their body size. It is generally noted a positive correlation between the size of the beetles and the size of the 60
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UNIVERSIDAD AUSTRAL DE CHILE FACULT
Page 3 and 4:
DIVERSIDAD Y CONTROL BIOLÓGICO DE
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ÍNDICE DE CONTENIDOS INTRODUCCIÓN
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4.- CAPÍTULO CUARTO: ANÁLISIS DE
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CAPÍTULO I. INDICE DE CUADROS Tabl
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CAPÍTULO I. ÍNDICE DE FIGURAS Fig
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Figure 5. Rarefaction curves for th
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ABSTRACT About 10% of Southern Chil
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Sin embargo, a pesar de esta percep
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preeminencia de esta idea ha sido e
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niveles tróficos completos o grand
Page 23 and 24: Se ha propuesto diversos enfoques p
Page 25 and 26: El control de esta especie se reali
Page 27 and 28: con la consiguiente pérdida o dism
Page 29 and 30: 4. Numerosos estudios se concentran
Page 31 and 32: 1.- CAPÍTULO PRIMERO: DIVERSIDAD G
Page 33 and 34: sample, showing the potential use o
Page 35 and 36: and put it in a phylogeographical p
Page 37 and 38: centrifugation and supernatant was
Page 39 and 40: (Schneider and Excoffier, 1999; Alt
Page 41 and 42: All the putative populations showed
Page 43 and 44: strongly influenced by insect host
Page 45 and 46: supported a geographical sub-divisi
Page 47 and 48: Neuveglise C, Brygoo Y, Vercrambe B
Page 49 and 50: Table 1. Environmental data for the
Page 51 and 52: B907 Poike 27º 06' 109º 21' Easte
Page 53 and 54: B606 Lago Icalma 38º 50' 71º 20'
Page 55 and 56: Figure 1. NJ tree of the B fragment
Page 57 and 58: Figure 2. Haplotype tree inferred f
Page 59 and 60: Figure 4. Mismatch distributions of
Page 61 and 62: Figure 5. Haplotype diversity in th
Page 63 and 64: Table 6. Analyses of molecular vari
Page 65 and 66: Table 8. Pairwise differentiation e
Page 67 and 68: CONSERVATION BIOLOGICAL CONTROL OF
Page 69 and 70: Introduction. In last decades, mode
Page 71 and 72: a dose of 10 12 spores per ha was s
Page 73: aerea were very low at 1 and 30 day
Page 77 and 78: fields that are sprayed with pestic
Page 79 and 80: affected species, when present, whe
Page 81 and 82: Kiss, B., Samu, F., 2000. Evaluatio
Page 83 and 84: Wilby, A., Villareal, S., Lan, L.,
Page 85 and 86: ARANEAE Gnaphosidae 253 54 % Lycosi
Page 87 and 88: Activity density (individuals per p
Page 89 and 90: NON-TARGET EFFECTS OF Dalaca pallen
Page 91 and 92: same percentage of mortality on lar
Page 93 and 94: Treatments were applied on 15 Octob
Page 95 and 96: (Departamento de Producción y Sani
Page 97 and 98: Predators. Data set I. The principa
Page 99 and 100: predators extracted from soil cores
Page 101 and 102: particularly carabids. Most of the
Page 103 and 104: the consistent results allow us to
Page 105 and 106: Kenmore, P.E., Cariño, F., Perez,
Page 107 and 108: Traugott, M., Strasser, H. and Prie
Page 109 and 110: Table 2. Significance of treatment
Page 111 and 112: Figure 1. Persistence of B. bassian
Page 113 and 114: Figure 3. Principal response curve
Page 115 and 116: Figure 5. Principal response curve
Page 117 and 118: RESPONSE OF GRASSLAND SOIL ARTHROPO
Page 119 and 120: Introduction. Declining diversity h
Page 121 and 122: Fungus. Beauveria bassiana strain Q
Page 123 and 124: Data collection. The abundance and
Page 125 and 126:
N is the total number of individual
Page 127 and 128:
catches), while dominant species re
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knowledge of South Chile grassland
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Dennis, P., 2003. Sensitivity of up
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invertebrates. In: IFOAM 2000 The W
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Figure 2. Estimated numbers Beauver
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Figure 4. Effects of B. bassiana an
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Figure 6. Rarefaction curves for th
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genética coincide con la zona de m
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Crosonychus viridis, Trechisibus an
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depredadores de lepidópteros, en l
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Respuesta a nivel de grupos funcion
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La conservación de los herbívoros
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Se ha propuesto que esta hipotétic
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En esta línea de razonamiento, las
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suceda en sistemas simples con poco
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BIBLIOGRAFIA Alarcón R. 1997. Resp
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isolated from the European cockchaf
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Hardin MR, Benrey, M Coll, WO Lamp,
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Lockwood JA, 1993. Environmental is
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Pimentel D, C Glenister, S Fast y D
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Swift MJ, J Vandermeer, PS Ramakris
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Zelada SH, 1998. Rol de la franja d
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Anexo 1. Índices de severidad de l
Page 173 and 174:
Anexo 3. Capturas provenientes de l
Page 175 and 176:
Page 177:
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