Search

Dentre os biomas brasileiros, o Cerrado é o segundo em extensão territorial e em diversidade de espécies vegetais e animais. A biodiversidade do Cerrado tem sido estudada no que tange a sua flora e fauna, carecendo de dados de microorganismos representantes da microfauna, a exemplo dos nematoides de galhas radiculares. Meloidogyne spp. são nematoides endoparasitas sedentários de plantas. A sua presença em solo de áreas com vegetação nativa de cerrado, sob preservação, é um forte indício de que a sua permanência ocorre devido ao parasitismo de plantas nativas. Este trabalho objetivou estudar a hospedabilidade de plantas ocorrentes no bioma cerrado a Meloidogyne spp. Foram selecionadas trinta e cinco espécies vegetais desse bioma, incluindo espécies gramíneas e arbóreas, para estudo da hospedabilidade frente a três isolados de Meloidogyne coletados em área nativa de cerrado sob preservação (Meloidogyne incognita, Meloidogyne javanica e Meloidogyne morocciensis), além de uma espécie até então exótica ao cerrado (Meloidogyne paranaensis). Foram inoculados 5.000 ovos e eventuais juvenis de segundo estádio (J2) de cada espécie de nematoide por planta. Os experimentos foram conduzidos com 35 tratamentos (plantas nativas) e 5 repetições, tendo sido repetidos no tempo. As variáveis avaliadas foram índice de galhas e de massas de ovos, ovos e J2 por grama de raiz e fator de reprodução, além da sintomatologia causada pelos nematoides nas raízes. As seguintes espécies vegetais foram consideradas hospedeiras, com média do Fator de Reprodução (FR)>1,0: Triplaris gardneriana para Meloidogyne javanica, Meloidogyne incognita e Meloidogyne morocciensis; Andropogon bicornis para Meloidogyne javanica e Meloidogyne incognita e Copaifera langsdorffii para Meloidogyne incognita. As seguintes espécies vegetais foram classificadas como hospedeiras potenciais, com FR>1,0 para pelo menos uma das repetições: Copaifera langsdorffii para Meloidogyne morocciensis; Esenbeckia leiocarpa para Meloidogyne javanica e Guibourtia hymenifolia para Meloidogyne incognita. As demais espécies vegetais foram classificadas como não hospedeiras para as condições deste estudo. As plantas inoculadas apresentaram sintomas variados nas raízes como a presença de galhas associadas a massas de ovos, formação de massas de ovos sem galhas, rachaduras com massas de ovos e ausência de galhas e intumescimento com massas de ovos.

Background: Among the pathogens that reduce cotton productivity in Brazil, Meloidogyne incognita is one of the most important as it causes severe yield losses and is widespread. The most recommended methods for control of this species are the use of resistant cultivars and crop rotation systems. In Brazil, M. incognita races 3 and 4 have already been reported as cotton parasites but the race 3 is the most commonly found and widely disseminated.This work aimed at selecting virulent and aggressive populations of M. incognita race 3 for testing sources of resistance to this nematode in cotton genotypes.Results: The three isolates of M. incognita race 3 were important for screening of resistant cotton genotypes. The isolate from Umuarama was the most aggressive followed by Moreira Sales and Iporã. The genotypes CD 05-419, CD 05-945, CD 05-1087 and CD 05-1170 showed good performance against M. incognita race 3 in both greenhouse and field conditions.Conclusions: The cotton genotypes CD05-945, CD05-1170, CD05-1087 and CD05-419 will be selected for future work involving tests for resistance against other important cotton pathogens. Those genotypes can also be used as source of genes for resistance to nematodes in cotton breeding programs. The search for virulent and aggressive M. incognita isolates was very important when screening for resistance in cotton germplasm.

A significant portion of the Cerrado (Brazilian savanna) has been replaced by major crops such as soybean. This may reveal populations of nematodes with different genetic backgrounds compared to cultivated fields. The objectives of this study were to evaluate the genetic variability and aggressiveness of isolates ofMeloidogynespp., contrasting nematodes from preserved areas of the Cerrado with those originating from cultivated soybean fields. Cluster analysis separated isolates ofMeloidogynespp. and isolates from Cerrado and soybean but did not separate an aggressiveMeloidogyne morocciensisisolate. The aggressiveness of six selected populations ofMeloidogynespp. from Cerrado and soybean against soybean cultivars was evaluated. Results showed that populations ofM. javanicaandM. incognitafrom Cerrado and soybean showed similar aggressiveness. However, forM. morocciensis, the population from soybean was much more aggressive than the one from Cerrado. Aggressiveness is a very intriguing subject that needs special attention for future research in nematology.

‘Manipueira’ is the common name of a liquid residue discharged from Manihot esculenta starch factories that is rich in nutrients and cyanogenic glycosides. The goal of this work was to study the nematicide effect of ‘manipueira’ in the control of Meloidogyne incognita in field grown with tomato plants during winter and summer seasons. The ‘manipueira’ used in this work was collected at a cassava starch factory located in Marechal Cândido Rondon, Parana State, Brazil. For both assays (winter and summer), tomatoes were cultivated in areas naturally infested with M. incognita. The experimental design adopted was completely randomized with 4 treatments (manipueira diluted in water at 10% concentration, manipueira at 25%, manipueira at 50% and the control containing only water) and 4 replicates. The winter assay was set up in a field and cultivated with staked tomatoes cv. Santa Cruz KaDa under protection from cold. The summer assay was conducted in an open field with the cultivation of industrial tomato cv. Rio Grande. The variables assessed for both assays were dry mass and fresh mass of tomato shoots, number of galls and eggs per tomato root system, and fruit yield (g). For both assays the 10%, 25% and 50% manipueira treatments were superior to the control for all the variables analyzed. No statistical difference was found among manipueira treatments. Tomato plants showed improved development when manipueira was applied at 50% concentration.

Root-knot nematodes (RKN), Meloidogyne spp., have major economic impact on coffee production in Central and South America. Genetic control of RKN constitutes an essential part for integrated pest management strategy. The objective of this study was to evaluate the resistance of Coffea canephora genotypes (clones) to Meloidogyne spp. Sensitive and drought-tolerant coffee genotypes were used to infer their resistance using nematode reproduction factor and histopathology. Eight clonal genotypes were highly resistant to M. paranaensis. ‘Clone 14’ (drought-tolerant) and ‘ESN2010-04’ were the only genotypes highly resistant and moderately resistant, respectively, to both M. incognita races 3 and 1. Several clones were highly resistant to both avirulent and virulent M. exigua. Clone 14 and ESN2010-04 showed multiple resistance to major RKNs tested. Roots of ‘clone 14’ (resistant) and ‘clone 22’ (susceptible) were histologically studied against infection by M. incognita race 3 and M. paranaensis. Reduction of juvenile (J2) penetration in clone 14 was first seen at 2 to 6 days after inoculation (DAI). Apparent early hypersensitive reaction (HR) was seen in root cortex between 4 and 6 DAI, which led to cell death and prevention of some nematode development. At 12 to 20 DAI, giant cells formed in the vascular cylinder, besides normal development into J3/J4. From 32 to 45 DAI, giant cells were completely degenerated. Late, intense HR and cell death were frequently observed around young females and giant cells reported for the first time in coffee pathosystem. These results provide rational bases for future studies, including prospection, characterization, and expression profiling of genomic loci involved in both drought tolerance and resistance to multiple RKN species.

The Cerrado biome represents a hotspot of biodiversity. Despite this, the nematofauna in this biome has not been well characterized, especially that related to root-knot nematodes. This work aimed to identify Meloidogyne species present in different cerrado vegetations and to investigate potential hosts of Meloidogyne javanica in this biome. Soil samples (250) were collected in native areas of cerrado vegetation located at the National Park of Brasilia (PNB) (125 samples) and Agua Limpa Farm (FAL) (125 samples), and transferred to sterile pots. Single tomato plants cv. Santa Clara (susceptible) were transplanted into individual pots and maintained for 90 days under glasshouse. Females of Meloidogyne spp. were extracted from tomato roots and identified based upon esterase phenotypes and confirmed with PCR using specific sequence characterized amplified regions (SCAR) primers. Native plants were inoculated with 10 000 individuals (eggs + J2) of a pure culture of M. javanica and maintained under glasshouse for 6 months. From the 250 samples collected, 57 (22.8%) presented Meloidogyne spp. A total of 66 Meloidogyne populations were identified as follows: M. javanica (75.76%), M. incognita (10.60%), M. hapla (9.1%), M. morocciensis (3.03%) and M. arenaria (1.51%). The following esterase phenotypes were detected: M. javanica (J3 and J2), M. incognita (I1 and I2), M. hapla (H1), M. morocciensis (A3) and M. arenaria (A2). The SCAR primers incK14F/incK14R, Fjav/Rjav and Fh/Rh amplified specific fragments in M. incognita (399 bp), M. javanica (670 bp) and M. hapla (610 bp) and can be used for identification of indigenous Meloidogyne spp. from cerrado. The primer set Far/Rar is not specific for M. arenaria due to the amplification of DNA in M. morocciensis. Mimosa caesalpiniifolia was the only native plant in which M. javanica developed a high reproductive rate, and it is probably a host for this nematode in cerrado.

International audience; Meloidogyne incognita is one of the most polyphagous species of root-knot nematodes occurring in Brazil and worldwide. Eight M. incognita isolates were studied, representing two enzymatic phenotypes (esterase and malate desydrogenase: I1/N1, I2/N1) and four cryptic Meloidogyne sp.1 (S2/N1) isolates, representing one cytological type (3n = 40-46). Three M. hispanica isolates (Hi3/N1, 2n = 32-36) and two of an atypical Meloidogyne sp.2 (S2a/N3, 3n = 40-44) were included in this study for comparison. All isolates were tested with three M. incognita-specific molecular markers. The primer pairs B06F/R, miF/R and incK14F/R amplified three species-specific fragments of 1,200 bp, 955 bp and 399 bp, respectively for M. incognita and Meloidogyne sp.1 isolates. No amplification occurred in the M. hispanica and Meloidogyne sp.2 isolates, except with primers miF/R (1,650 bp). The genetic variability of the Meloidogyne spp. isolates was evaluated, using RAPD and ISSR markers. The phylogenetic analyses revealed two strongly supported monophyletic clades: clade I, consisting of M. hispanica and the atypical Meloidogyne sp.2 isolates, and clade II, clustering together all M. incognita and the Meloidogyne sp.1 isolates. Considering the biometrical, cytological and molecular approaches, it was possible to conclude that the isolates with three enzymatic phenotypes (I1/N1, I2/N1 and S2/N1) presented the characteristics described for M. incognita. Some correlations were detected between the isozymatic phenotypes and the tree topology (S2a/N3, Hi3/N1, I1/N1, S2/N1), but no strict correlation could be observed for the phenotype I2/N1 and one isolate of S2/N1. Morphologically, the Msp.2 isolates differ from M. incognita and M. hispanica by the female stylet features presenting straight cone tip and round pear shaped knobs, posteriorly sloping. The results of this study suggested that the Msp.2 isolates with phenotypes S2aN3 belong to a new or an unidentified species closely related to M. hispanica.

Com o objetivo de estudar a ocorrência de nematoides fitoparasitos em frutíferas cultivadas na região noroeste do Paraná, realizou-se um levantamento, envolvendo 124 amostras de solo e raízes coletadas de 19 espécies de frutíferas, em 15 municípios, no período de dezembro/2007 a fevereiro/2009. As amostras foram submetidas a extrações e avaliadas sob microscópio óptico. Foram constatados nove diferentes gêneros de nematoides. Em citros, a espécie mais frequente e abundante foi Tylenchulus semipenetrans, sendo também recuperados das amostras os gêneros Meloidogyne, Pratylenchus, Helicotylenchus, Xiphinema, Trichodorus, Mesocriconema e Dolichodorus. Nas demais frutíferas, os gêneros observados foram Meloidogyne, Pratylenchus, Helicotylenchus e Hemicycliophora. A maior abundância de Pratylenchus brachyurus ocorreu em abacaxizeiro, Meloidogyne incognita em figueira e caquizeiro, e Helicotylenchus dihystera e H. multicinctus em bananeira. Os principais gêneros de fitonematoides foram constatados em aproximadamente 50% das amostras, podendo representar risco para fruteiras da região se não manejados adequadamente. A survey was carried out in order to study the occurrence of plant parasitic nematodes in fruit crops in the Northwest of Paraná, from December 2007 to February 2009. A hundred and twenty four soil and roots samples were collected from 19 species of fruit crops in 15 different municipalities. Nematodes were extracted from the samples and identified under an optical microscope. Nine genera of plant parasitic nematodes were found. In citrus, the most abundant species was Tylenchulus semipenetrans, but it was also recovered Meloidogyne, Pratylenchus, Helicotylenchus, Xiphinema, Trichodorus, Mesocriconema and Dolichodorus. In the other fruit crops, Meloidogyne, Pratylenchus, Helicotylenchus and Hemicycliophora were recovered. Pratylenchus brachyurus was most abundant in pineapple crops, Meloidogyne incognita in fig and persimmon, and Helicotylenchus dihystera and H. multicinctus in banana. The main plant parasitic nematode genera were found in approximately 50% of the samples collected, which may represent a possible threat to regional fruit production if not managed adequately.

Abstract Flavonoids have diverse roles in plants, including defence against plant pathogens and regulation of local auxin transport. Flavonoids have been shown to be produced in feeding sites of root-knot nematodes induced in a leguminous plant, and it has previously been suggested that they may be responsible for manipulation of local auxin levels that underlie early feeding site development. Here we show that flavonoids are also produced in developing syncytia induced by Heterodera schachtii and in galls induced by Xiphinema diversicaudatum in a non-leguminous plant, Arabidopsis thaliana. We further investigated whether flavonoids are required for normal feeding site development by screening mutant lines of A. thaliana, defective in various parts of the flavonoid biosynthetic pathway, with H. schachtii. None of the lines showed a reduced capacity to support nematode infection and some showed a statistically significant increase in the numbers of female nematodes that developed. These data suggest that flavonoids are produced as part of the defence response to nematode infection rather than being an integral component of the mechanisms used by nematodes to induce feeding sites.

Phylogenetic studies have shown that parasitism of plants by nematodes has arisen independently on at least three separate occasions. We argue that horizontal gene transfer has played a critical role in the evolution of plant parasitism on each occasion. In addition, we discuss evidence that suggests this process has driven the evolution of other life strategies within the Nematoda and that it may be considerably more common within the Phylum than commonly thought. We review recent literature that shows horizontal gene transfer to nematodes has occurred from both bacteria and fungi.

We report the results of a small-scale expressed sequence tag project performed on the ectoparasitic nematode Xiphinema index. Approximately 1400 genes were sequenced, 70% from a cDNA library generated from dissected basal bulbs (containing the pharyngeal gland cells) and 30% from cDNA libraries generated from whole mixed stage nematodes. A large portion of the bulb library (48%) was composed of proteins with no matches in the database. Further analysis of these genes revealed that a total of 51 contigs were present, half of which encoded novel secreted proteins. By contrast, the whole nematode library contained more housekeeping and nematode-specific genes. Only one of the novel genes from the whole nematode library had a predicted signal peptide at the N-terminus. Genes encoding transthyretin-like proteins were abundant in the bulb library and in situ hybridisation confirmed that one of these is expressed in the basal bulb. Genes encoding a variety of proteases, which were shown using in situ hybridisation to be expressed in the gut, were also identified.

SUMMARY Some plant endoparasitic nematodes are biotrophic and induce remarkable changes in their hosts in order to ensure a continuous supply of food. Proteins secreted from oesophageal gland cells have been implicated in this pathogenic process. A potentially secreted chorismate mutase has been isolated from the potato cyst nematode Globodera pallida. The gene encoding this protein is expressed in the subventral oesophageal gland cells of the nematode, and the mRNA derived from this gene is only present in the early parasitic stages. Sequence analysis of this gene shows that, like other genes involved in the host-parasite interaction of plant parasitic nematodes, it is likely to have been acquired by horizontal gene transfer from bacteria. The presence of a signal peptide in the deduced amino acid sequence of the G. pallida chorismate mutase and its expression in the subventral oesophageal gland cells suggest that it is secreted from the nematode, pointing to a role for the protein in the host-parasite interaction. The shikimate pathway, of which chorismate mutase is normally a part, is not found in animals but is present in plants and bacteria. In plants it gives rise to a variety of compounds which are important in amino acid synthesis and defence signalling pathways, as well as auxins, which have been implicated in the early development of nematode feeding sites. The potential roles of a nematode chorismate mutase are discussed.

Pseudocercospora bolkanii sp. nov., and P. luzardii sp. nov., were collected in the Brazilian cerrado on leaves of Strychnos pseudoquina , and Hancornia speciosa , respectively. Prathigada backmanii sp. nov., is described on leaf spots of Bowdichia virgilioides. Pseudocercospora curatellae on Curatella americana is illustrated in detail.

As part of an inventory of mycodiversity in the Brazilian Cerrado new coelomycetes were collected and are herein described: Phyllosticta xylopiae-sericeae sp. nov., Dinemasporium duguetiae sp. nov., Harknessia salvertiana sp. nov., Harknessia qualeae sp. nov. on living leaves of Xylopia sericea, Duguetia furfuracea, Salvertia convallariodora, and Qualea grandiflora, respectively. Pseudothiopsella hirtellae is reported on a new host, Hirtella gracilipes, and for the first time illustrated in detail.

SUMMARY Some plant endoparasitic nematodes are biotrophic and induce remarkable changes in their hosts in order to ensure a continuous supply of food. Proteins secreted from oesophageal gland cells have been implicated in this pathogenic process. A potentially secreted chorismate mutase has been isolated from the potato cyst nematode Globodera pallida. The gene encoding this protein is expressed in the subventral oesophageal gland cells of the nematode, and the mRNA derived from this gene is only present in the early parasitic stages. Sequence analysis of this gene shows that, like other genes involved in the host-parasite interaction of plant parasitic nematodes, it is likely to have been acquired by horizontal gene transfer from bacteria. The presence of a signal peptide in the deduced amino acid sequence of the G. pallida chorismate mutase and its expression in the subventral oesophageal gland cells suggest that it is secreted from the nematode, pointing to a role for the protein in the host-parasite interaction. The shikimate pathway, of which chorismate mutase is normally a part, is not found in animals but is present in plants and bacteria. In plants it gives rise to a variety of compounds which are important in amino acid synthesis and defence signalling pathways, as well as auxins, which have been implicated in the early development of nematode feeding sites. The potential roles of a nematode chorismate mutase are discussed.

Objetivou-se estudar o efeito nematicida de manipueira no controle de Meloidogyne incognita. Testes in vitro foram divididos em dois ensaios inteiramente casualizados: 1. manipueira a 100%, 75%, 50% e 25% em 12 repetições; 2. manipueira a 15%, 10%, 8%, 6%, 4% e 2% em 5 repetições. O ensaio em vasos seguiu o delineamento inteiramente casualisado com manipueira a 10%, 25% e 50% em 5 repetições. Para ambos os ensaios utilizou-se o tratamento somente água como testemunha positiva e Carbofuran (50 mg.L-1 de ingrediente ativo (i.a.) ou 2 g de produto comercial/vaso) como negativa. Para os ensaios in vitro foram avaliados nematóides vivos e mortos e número de galhas em plantas inoculadas. Para os ensaios em vaso foram avaliadas as variáveis altura de plantas, comprimento de raízes, número de galhas, número de ovos e fator de reprodução (FR). Os resultados in vitro demonstraram que os tratamentos com manipueira até 10% de diluição apresentaram 100% de controle. O ensaio com tomateiros previamente inoculados demonstrou que o tratamento manipueira 50% causou um melhor desenvolvimento da parte aérea das plantas de tomate. Os tratamentos manipueira a 10% e 25% foram mais efetivos no controle de M. incognita em vasos. The aim of this work was to study the nematicidal effect of manipueira on the control of Meloidogyne incognita. In vitro tests were split into two completely randomized assays: 1. manipueira 100%, 75%, 50% and 25% in 12 replications; 2. manipueira 15%, 10%, 8%, 6%, 4% and 2% in 5 replications. The pot assay followed a completely randomized design with the treatments manipueira 10%, 25% and 50% in 5 replications. For both assays the positive control was water and the negative control was the nematicide Carbofuran (50 mg.L-1 of active ingredient (a.i.) or 2 g of commercial product/pot). For in vitro assays the variables assessed were live or dead nematodes and number of galls on inoculated plants. For the pot assay the variables evaluated were plant height, root length, number of galls, number of eggs and reproduction factor (RF). The in vitro results indicated that only the manipueira treatments from 100% to 10% dilution showed maximum control. The pot assay demonstrated that the treatment manipueira 50% caused better development of tomato shoots than the others. However, manipueira 10% and 25% were more effective against of M. incognita in pots.

Trabalho desenvolvido em parceria com In Vitro Biotecnologia de Plantas, Brasília, DF e apoio do Programa RHAE/CNPq. Estudou-se o efeito da época do início da aplicação de fungicida na severidade da mancha de Mycosphaerella fragariae em parcelas experimentais de morango cv. IAC-Campinas. O ensaio foi conduzido em área produtora (Brazlândia, DF) em blocos ao acaso com seis tratamentos (épocas de início de pulverização) e quatro repetições. Foram efetuadas aplicações quinzenais com o p.a. prochloraz (450 g i.a/litro) na dosagem de 100 ml/100 litros de água, e testadas as épocas de início de aplicação: Plantio (pulverização por ocasião do plantio das mudas, com um total de dez aplicações); Flor1 (após a primeira florada, oito aplicações); Flor2 (após a segunda florada, seis aplicações); Flor3 (após a terceira florada, quatro aplicações); Flor4 (após a quarta florada, duas aplicações) e Test (testemunha pulverizada com água desde o transplantio). As seguintes variáveis foram avaliadas: produção total acumulada; severidade de doença; número de folhas mortas e sadias; número de hastes lesionadas e sadias. Os resultados indicaram que os tratamentos Plantio e Flor1 foram superiores aos demais em todos os critérios (Duncan, 5%). O tratamento Flor2 apresentou controle intermediário de doença. Os demais tratamentos não apresentaram diferenças estatísticas significativas entre si. __________________________________________________________________________________________ ABSTRACT The effect of timing of first fungicide application on the severity of Mycosphaerella leaf spot (Mycosphaerella fragariae) on strawberry cv. IAC-Campinas was studied in field plots located in Brazlândia-DF, Brazil. The experiment was conducted as a randomized complete block design with six treatments (times of first fungicide delivery) and four replicates. The fungicide (prochloraz - 450 g a.i./L) was delivered at a dosage of 100 ml/100 L of water, on a 15-day schedule. The following periods for first application were tested: "Plant": at transplant stage; with a total of ten fungicide applications; "Flor1": at first flowering stage, total of eight applications; "Flor2": at second flowering, total of six applications; "Flor3": at third flowering, total of four applications; "Flor4": at fourth flowering, total of two applications; "Test": control plots, sprayed with water starting at transplant. Treatments were ranked accordingly to total fruit yield; disease severity; number of dead and healthy leaves; number of infected and healthy stems. Results indicated that treatments "Plant" and "Flor1" provided a most efficient control of the disease (Duncan, 5%), followed by treatment "Flor2". Treatments "Flor3", "Flor4" and "Test" resulted in poor disease control and were not statistically different.

Estudou-se o efeito da época do início da aplicação de fungicida na severidade da mancha de Mycosphaerella fragariae em parcelas experimentais de morango cv. IAC-Campinas. O ensaio foi conduzido em área produtora (Brazlândia, DF) em blocos ao acaso com seis tratamentos (épocas de início de pulverização) e quatro repetições. Foram efetuadas aplicações quinzenais com o p.a. prochloraz (450 g i.a/litro) na dosagem de 100 ml/100 litros de água, e testadas as épocas de início de aplicação: Plantio (pulverização por ocasião do plantio das mudas, com um total de dez aplicações); Flor1 (após a primeira florada, oito aplicações); Flor2 (após a segunda florada, seis aplicações); Flor3 (após a terceira florada, quatro aplicações); Flor4 (após a quarta florada, duas aplicações) e Test (testemunha pulverizada com água desde o transplantio). As seguintes variáveis foram avaliadas: produção total acumulada; severidade de doença; número de folhas mortas e sadias; número de hastes lesionadas e sadias. Os resultados indicaram que os tratamentos Plantio e Flor1 foram superiores aos demais em todos os critérios (Duncan, 5%). O tratamento Flor2 apresentou controle intermediário de doença. Os demais tratamentos não apresentaram diferenças estatísticas significativas entre si.The effect of timing of first fungicide application on the severity of Mycosphaerella leaf spot (Mycosphaerella fragariae) on strawberry cv. IAC-Campinas was studied in field plots located in Brazlândia-DF, Brazil. The experiment was conducted as a randomized complete block design with six treatments (times of first fungicide delivery) and four replicates. The fungicide (prochloraz - 450 g a.i./L) was delivered at a dosage of 100 ml/100 L of water, on a 15-day schedule. The following periods for first application were tested: "Plant": at transplant stage; with a total of ten fungicide applications; "Flor1": at first flowering stage, total of eight applications; "Flor2": at second flowering, total of six applications; "Flor3": at third flowering, total of four applications; "Flor4": at fourth flowering, total of two applications; "Test": control plots, sprayed with water starting at transplant. Treatments were ranked accordingly to total fruit yield; disease severity; number of dead and healthy leaves; number of infected and healthy stems. Results indicated that treatments "Plant" and "Flor1" provided a most efficient control of the disease (Duncan, 5%), followed by treatment "Flor2". Treatments "Flor3", "Flor4" and "Test" resulted in poor disease control and were not statistically different.

A study of the holotype and several collections of Cercospora zeyrae on leaves of Zeyheria digitalis from the Brazilian cerrado showed that it is actually a Pseudocercospora species with amphigenous fruit structures, here designated as P. zeyheriae (Henn.) comb. nov.

Onze fungicidas foram analisados in vitro e seus efeitos testados em campo para o controle de Colletotrichum acutatum, agente da flor-preta do morangueiro (Fragaria X ananassa). Os tratamentos (campo) foram (dosagens de i.a/ 100 l): iprodione (75 ml), benomil (100 g), tebuconazole (50 ml), tiofanato metílico (70 g), prochloraz (100 ml), propiconazole (50 ml), mancozeb (200 g), folpet (270 g), sulfato de cobre (200 g) e chlorotalonil (200 g), em pulverizações semanais (protetores) e quinzenais (sistêmicos). Foram avaliados a produção de frutos e o número de flores com sintoma de queima. Nos testes de fungitoxicidade in vitro, estudou-se o crescimento micelial, a germinação de conídios e a formação de apressórios. Nos testes in vitro foram utilizadas as concentrações de 1 e 10 ppm de i.a. para todos os fungicidas e posteriormente testadas as concentrações de 0,01, 0,1 e 1 ppm para os mais eficientes, e 10, 50 e 100 ppm para os menos eficazes. Os que resultaram em maior inibição micelial em baixas concentrações foram prochloraz e tebuconazole e os que menos inibiram o crescimento micelial foram sulfato de cobre, clorotalonil e folpet. Para inibir a germinação conidial mostraram-se mais eficientes chlorotalonil, tebuconazole, prochloraz e benomil, e para inibir a formação de apressórios, chlorotalonil e benomil. Os resultados de campo diferiram parcialmente dos testes in vitro: prochloraz e sulfato de cobre apresentaram os menores percentuais de flores doentes (53- 55%), enquanto benomil apresentou 100% de ataque. Embora prochloraz, seguido de iprodione, folpet e mancozeb tenham resultado em maiores produções, nenhum fungicida controlou a doença satisfatoriamente. Eleven fungicides were tested in the field, and their effects on Colletotrichum acutatum, the agent of strawberry (Fragaria X ananassa) flower blight,, were examined in vitro. Treatments and doses tested in the field per 100 l of water were iprodione (75 ml), benomyl (100 g), tebuconazole (50 ml), methyl thiofanate (70g), prochloraz (100 ml), propiconazole (50 ml), mancozeb (200 g), folpet (270 g), copper sulfate (200 g) and chlorothalonil (200 g), sprayed weekly (protectants) or bi-weekly (systemic). Fruit yield and number of blighted flowers were computed. For the in vitro fungitoxicity tests, the rate of mycelial growth rate of conidial germination and appressorium formation were studied in fungicide dilutions. In vitro tests were conducted with 1 and 10 ppm, and subsequently at 0.01, 0.1 and 1 ppm for the most efficient products and at 10, 50 and 100 ppm, for the least efficient a.i. The fungicides that resulted in least mycelial growth at the lowest concentrations were prochloraz and tebuconazole, and the ones that least inhibited mycelial growth the was copper sulfate, chlorothalonil and folpet. Most efficient products for inhibition of conidial germination were chlorothalonil, tebuconazole, prochloraz and benomyl. Most efficient products for inhibition of appressorium formation were chlorothalonil and benomyl. Field results were partially different from in vitro results: prochloraz and copper sulfate had the lowest percentages of blighted flowers (53-55%), whereas benomyl had 100% blighted flowers. Although prochloraz, followed by iprodione, folpet and mancozeb resulted in larger fruit yields, no product alone provided sufficient control of strawberry flower blight.

Rhinocladium pulchrum on dead bark is, for the first time, collected and illustrated from Minas Gerais, Brazil. Conoplea abietina and C. mangenotii, both lacking discrete lateral conidiogenous cells on the conidiophores, are transferred to new combinations in Rhinocladium.