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The accurate identification of root-knot nematode (RKN) species (Meloidogyne spp.) is essential for implementing management strategies. Methods based on the morphology of adults, isozymes phenotypes and DNA analysis can be used for the diagnosis of RKN. Traditionally, RKN species are identified by the analysis of the perineal patterns and esterase phenotypes. For both procedures, mature females are required. Over the last few decades, accurate and rapid molecular techniques have been validated for RKN diagnosis, including eggs, juveniles and adults as DNA sources. Here, we emphasized the methods used for diagnosis of RKN, including emerging molecular techniques, focusing on the major species reported in Brazil.

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ResumoO uso de extratos vegetais com propriedades nematicidas no controle de fitonematóides representa mais uma alternativa para os pequenos produtores, com valor prático e econômico, e sem riscos de contaminação do ambiente. A adição ao solo dos extratos aquosos de 20 espécies de plantas foi avaliada sobre a população de Meloidogyne javanica em plantas de tomateiro, em casa de vegetação. Estas foram divididas em dois grupos e avaliadas em dois experimentos separados. No mesmo dia em que se infestou o solo com 5.000 ovos do nematóide, adicionou-se 20 mL dos extratos aquosos obtidos de folhas de artemísia (Chrysanthemum parthenium), bardana (Arctium lappa), capim cidreira (Cymbopogon citratus), carqueja (Bacharis trimera), cavalinha (Equisetum sp.), cinamomo (Melia azedarach), hortelã (Mentha sp.), mamona (Ricinus communis), manjericão (Ocimum basilicum), melão-de-São-Caetano (Momordica charantia), arruda (Ruta graveolens), falso-boldo (Coleus barbatus), confrei (Symphitum officinalis), erva-de-bicho (Polygonum acre), feijão-de-porco (Canavalia ensiformis), funcho (Foeniculum vulgare), guiné (Petiveria alliacea), mentrasto (Ageratum conyzoides), mucunacinza (Mucuna pruriens) e nim (Azadirachta indica). Água destilada foi adicionada ao solo como tratamento testemunha. Após 60 dias, avaliou-se a altura das plantas, o peso fresco da parte aérea e da raiz e os números de galhas e de ovos por sistema radicular. Os extratos de hortelã, bardana e mamona reduziram o número de galhas em 75,6%, 65,7% e 54,4%, e o número de ovos em 81,7%, 75,9% e 56,6%, respectivamente. Palavras-chave: Fitonematóides, controle alternativo, nematóides das galhas, compostos naturais AbstractThe use of plant extracts with nematicidal properties to control plant nematodes can be a useful alternative to small farmers, regarding its low cost and non-toxic effects. The effect of the addition into the soil of aqueous extracts of 20 plant species on Meloidogyne javanica in plants of tomato was studied at greenhouse conditions. These were divided into two groups and evaluated in two separate experiments. The soil in the 2.0 L pots was infested with 5,000 eggs and, in the same day, it was applied 20 mL of aqueous extracts of the 20 plant species (Chrysanthemum parthenium, Arctium lappa, Cymbopogon

Stromatinia cepivora (= Sclerotium cepivorum), causal agent of the white rot, is a major soilborne pathogen that attacks garlic (Allium sativum L.), onion (Allium cepa L.), and other plants of the Alliacea family. The pathogen is difficult to control because it survives as sclerotia for decades in soil. White rot can cause total crop losses when sclerotia levels are high in soil and environmental conditions favorable for disease development. Aspects of the biology and epidemiology of S. cepivora have been investigated extensively worldwide. These studies have provided essential information to develop different control strategies. Currently, white rot management is based primarily on the application of fungicides and biocontrol agents to protect the crop against infection, and the use of natural and synthetic germination stimulants of sclerotia, soil fumigation and solarization to reduce sclerotia density in soils. In Brazil, few studies have been conducted to understand white rot epidemiology and effectiveness of control measures currently available, despite the disease being an economically important in garlic and onion production regions for many years. This review provides updated information on the biology of S. cepivora, and epidemiology and control of white rot to identify important knowledge gaps and future research directions for white rot in Brazil.

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In the present work, it was evaluated the in vitro effect of 12 isolates from the fungal species Arthrobotrys, Duddingtonia, Nematoctonus and Monacrosporium genera in different conidial concentrations on the capture of Ancylostoma spp. dog infective larvae (L(3)), on 2% water-agar medium at 25 degrees C, at the end of a period of 7 days. The concentrations used for each nematophagous fungus were 1000, 5000, 10,000, 15,000 and 20,000conidia/Petri dish plated with 1000 Ancylostoma spp. L(3). All nematode-trapping fungi isolates tested reduced the averages of the uncaptured Ancylostoma spp. L(3) recovered, with the increase of the fungal inoculum concentration, in comparison to the fungus-free control (p<0.05). The adhesive network producing species were better predators than the constricting ring or adhesive knob producing species. Duddingtonia flagrans (Isolate CG768) was the most effective, reducing the averages of the uncaptured Ancylostoma spp. L(3) recovered in 92.8%, 96.3%, 97.5%, 98.3% and 98.9%, respectively in five fungal inoculum concentrations established. Other effective nematophagous fungi were Arthrobotrys robusta (Isolate I31), which reduced the averages of the uncaptured Ancylostoma spp. L(3) recovered in 85.4%, 88.3%, 90.7%, 92.5% and 95.2%, and Arthrobotrys oligospora (Isolate A183), with reductions of 66.6%, 79.8%, 86.8%, 89.5% and 90.8%, respectively for both, in the five fungal inoculum concentrations established. No difference was found between Isolates A183 and I31 in the conidial concentrations of 15,000/Petri dish. Nematoctonus robustus (Isolate D1) and Arthrobotrys bronchophaga (Isolate AB) had the smallest percentages of reduction among the tested isolates and showed the lowest predacious activity. The Isolates CG768, I31 and A183 were considered potential biological control agents of Ancylostoma spp. dog free-living stages, being directly influenced by the fungal inoculum concentration.