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Discussion. In our opinion, the adopted combination of techniques (Althoff and Pellmyr, 2002), is well suited to deal with topics such as whose studied in this research. Some populations are far apart (even thousands of kilometers) enough to allow hypothetical vicariant events to occur. However, when the B fragment phylogeny was overlain on the current geographic distribution of the isolates, no clear pattern was observed. On the other hand, the AMOVA analysis do detect a small but significant population structuring, which could be resulted from more recent events, including human-mediated dispersal of the fungus through movement of crop plants and soil associated to them. The demographic analyses proved to be complementary to the phylogenetic approach. As noted by Althoff and Pellmyr (2002), when the phylogenetic approach reveals a geographic structure, demographic approach generally agrees. But when the phylogenetic approach fails to detect such a structure, especially if recent demographic changes has occurred, then the demographic approaches are useful in that temporal scale. In this particular fungal population, it seems to be the case and reinforces the use of a combined approach (Bernatchez, 2001; Althoff and Pellmyr, 2002). We expected a clear differentiation between Eastern Island and continental Chile, based in the brief period in which the island has been influenced by the continent (Eastern Island was anexed to Chile at 1888). The division was clear when AMOVA and pairwise comparisons were used, but the phylogenetic signal for this division was weak. Eight Eastern Island’s isolates were grouped closely, but other six isolates were sparsed in a large cluster including isolates from all remaining populations. Early studies conducted on B. bassiana did not agree on the putative genetic relatedness and geographic origin. While some authors reported that they are correlated (Wang et al., 2003; Yang et al., 2005), others did not support this conclusion (Aquino de Muro et al., 2003; Aquino de Muro et al., 2005; Berretta et al., 1998; Coates et al., 2002). The studies differ largely on sample size, molecular methods and statistical analysis, being hard to properly compare each other. Others authors have suggested that genetic relatedness is 27
strongly influenced by insect host (RAPD and RFLP, Maurer et al., 1997; RFLP, Viaud et al., 1996; ITS, Neuveglise et al., 1994). Again, this conclusion is refuted by other studies (ITS sequencing and RFLP, Coates et al., 2002; RAPD, Castrillo et al., 2004; Berreta et al., 1998; Urtz and Rice, 1997). The fungus Beauveria bassiana has been studied for more than 150 years and an asexual stage has been assumed for the most part of that period. In recent years, molecular studies have identified Beauveria as the asexual stage of Cordyceps spp., which reproduces by a sexual cycle. Despite of the evidence for this linking, it seems that Beauveria spp. is asexual for the most of its lifecycle. Under this condition, some genetic recombination still is possible through parasexual cycle, during which vegetatively compatible hyphae fuse to exchange genetic material (Paccola-Meirelles and Azevedo, 1991). However, the parasexual cycle in this species is controled by a strict recognition system and many different vegetative compatibility groups can be identified in a sample (Castrillo et al., 2004). Consequently, the genetic exchange seems quite restricted in B. bassiana s.l. Another plausible explanation for the phylogenetic pattern showed in the Figure 1 is related what Rehner and Buckley (2005) proposed as cryptic speciation into the morphologically defined B. bassiana. These authors reported that globally collected B. bassiana would be paraphyletic according to a two nuclear genes phylogeny, the elongation factor 1 alpha (EF1-α) and the ribosomal internal transcribed spacer (ITS). The combined analysis divided the previously identified B. bassiana isolates in two clades separated by B. brongniartii. The B locus phylogeny mostly resembles this pattern and consequently a subset of Chilean isolates, representative of the major B fragment clades, was additionally sequenced for EF1-α (Devotto and Rehner, unpub. data). One isolate was more related to B. amorpha than B. bassiana, while one strain was grouped in one of the B. bassiana clusters and the remaining nine isolates were included in the paraphyletic B. bassiana cluster. It will be necessary to include a larger Chilean sample in this proposed phylogeny to test if the Chilean population mirrors the pattern detected for the Beauveria genus. 28
Page 1 and 2: UNIVERSIDAD AUSTRAL DE CHILE FACULT
Page 3 and 4: DIVERSIDAD Y CONTROL BIOLÓGICO DE
Page 5 and 6: ÍNDICE DE CONTENIDOS INTRODUCCIÓN
Page 7 and 8: 4.- CAPÍTULO CUARTO: ANÁLISIS DE
Page 9 and 10: CAPÍTULO I. INDICE DE CUADROS Tabl
Page 11 and 12: CAPÍTULO I. ÍNDICE DE FIGURAS Fig
Page 13 and 14: Figure 5. Rarefaction curves for th
Page 15 and 16: ABSTRACT About 10% of Southern Chil
Page 17 and 18: Sin embargo, a pesar de esta percep
Page 19 and 20: preeminencia de esta idea ha sido e
Page 21 and 22: 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: All the putative populations showed
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 and 74: aerea were very low at 1 and 30 day
Page 75 and 76: explanation than no toxicity of the
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
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Treatments were applied on 15 Octob
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(Departamento de Producción y Sani
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Predators. Data set I. The principa
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predators extracted from soil cores
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particularly carabids. Most of the
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the consistent results allow us to
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Kenmore, P.E., Cariño, F., Perez,
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Traugott, M., Strasser, H. and Prie
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Table 2. Significance of treatment
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Figure 1. Persistence of B. bassian
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Figure 3. Principal response curve
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Figure 5. Principal response curve
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RESPONSE OF GRASSLAND SOIL ARTHROPO
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Introduction. Declining diversity h
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Fungus. Beauveria bassiana strain Q
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Data collection. The abundance and
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N is the total number of individual
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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
Page 165 and 166:
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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