Efeito de extratos aquosos de espécies de Asteraceae sobre Meloidogyne incognita

Abstract

RESUMOPalavras-chave adicionais: plantas antagonistas; nematóides das galhas, extratos botânicos.T he nema ticide a ctivity of a qu eou s extra cts of Wedelia (Sphagneticola trilobata), tridax daisy (Tridax procumbens), marigold (Tagetes patula), Mexican sunflower (Tithonia diversifolia), "botão de ouro" (Unxia suffruticosa) and Peruvian zinnia (Zinnia peruviana) was studied in vitro and in vivo on Meloidogyne incognita. The extracts were prepared at a ratio of 1.0 g of dry and crushed material to 10 ml of distilled water, stored for 24 hours, and then used in the experiments. In in vitro tests, 4.0 mL of crude extract and 2.0 ml of an aqueous suspension containing 200 nematode eggs were deposited on Petri plates of 5cm diameter and, fifteen days later, the number of hatched juveniles and the remaining eggs were counted to calculate the percentages of hatching. In in vivo tests, the extracts were separately applied by leaf spraying, root treatment and pouring onto the soil, weekly for 60 days. As control, only water was used in both experiments. The in vitro test showed that Ferreira, I.C.M.; Silva, G.S.; Nascimento, F.S. Effect of aqueous extracts of Asteraceae species on Meloidogyne incognita. Summa Phytopathologica, v.39, n.1, p.40-44, 2013. all extracts were effective in reducing the hatching of juveniles of M. inc ognita when compared to the control; the reduction percentages were 89.96%, 91.13%, 92.48%, 92.72%, 93.2% and 97.48% for tridax daisy, marigold, Mexican sunflower, Wedelia, "botão de ouro" and Peruvian zinnia, respectively, while in the in vivo assa y, trea tments did not have any effect on the root system weight of tomato plants; however, results differed between the used species and the way of application of the extract in the evaluation of the fresh weight of shoots. As to the reprodu ction ra te, none of the extra cts showed a sta tistica l difference, compared to control; however, compa ring the different ways of application, there was statistical difference when the extracts of trida x daisy a nd Mexica n su nflower were a pplied throu gh lea f spraying and root treatment, but there was no difference when these extracts were applied as irrigation on the soil.Estudou-se, in vitro e in vivo a atividade nematicida dos extratos aquosos de vedélia(Spha gneticola trilob ata), erva-de-touro (Tridax procumbens), cra vo-de-defu nto (Tage tes patula), girassol mexicano (Tithonia diversifolia), botão de ouro (Unx ia suffru tico sa) e zínia (Zinnia peruviana), sobre Meloidogyne incognita. Os extratos foram prepa rados na proporção de 1 ,0g do ma terial seco e triturado pa ra 10mL de água destilada e armazenados por 24h, sendo seguidamente utilizados nos experimentos. Nos testes in vitro, foram depositados 4,0mL do extrato bruto e 2,0mL de uma suspensão aquosa contendo 2 00 ovos do nematóide em pla ca s de Petri de 5 cm de diâmetro e, qu inze dia s a pós, procedeu -se a conta gem do nú mero de ju venis eclodidos e dos ovos remanescentes para o cálculo das porcentagens de eclosã o. Nos testes in v iv ...

Extracts and semi-purified fractions of Tagetes patula flowers in the control of root-knot nematodes

“…CAE: crude aqueous extract; CEWE: crude ethanol-water extract; CDAE: crude defatted aqueous extract; CEWDE: crude ethanolwater defatted extract. A similar result was described by Ferreira et al (2013), who reported that the aqueous extract of the aerial part of T. patula caused 91% inhibition of M. incognita J 2 hatching. However, the authors did not evaluate other species of Meloidogyne.…”

“…For these reasons, alternative control methods have been studied, including the use of both antagonistic plants and their extracts (BALDIN et al, 2012;FERREIRA et al, 2013). Antagonistic plants that negatively affect phytonematode populations include trap crops, non-host plants, and those that contain nematicidal and/or nematostatic compounds (ZAMBOLIM et al, 2007).…”

In vitro toxicity and control of Meloidogyne incognita in soybean by rosemary extract

“…In vitro toxicity and control of Meloidogyne incognita in soybean by rosemary extract Other pathosystems also show similar results; for example, Franzener et al (2007) demonstrated that weekly applications of an aqueous extract made from the leaves and flowers of T. patula to tomatoes (soil and aerial parts) reduced the number of galls and the RF of M. incognita, suggesting that T. patula extract can activate systemic defense mechanisms in these plants.…”

“…Plant extracts can control pathogens by direct antimicrobial activity or by inducing resistance to pests. For example, Tagetes patula extracts have been shown to control Meloidogyne incognita in tomatoes (FRANZENER et al, 2007), and essential oil of Rosmarinus officinalis can inhibit Meloidogyne javanica in soybeans . Borges et al (2013) found through in vitro trials that Azadirachta indica, Curcuma longa, and Crotalaria breviflora extracts are directly toxic to Meloidogyne incognita and Tubixaba tuxaua.…”

“…In addition to inhibiting egg hatching, Müller et al (2014) showed that rosemary extract also has a nematostatic effect, ceasing up to 97% of M. incognita movements, and inducing up to 83% of J2 deaths. Ferreira et al (2013) examined the potential of multiple plant extracts to control M. incognita juvenile hatching, including Tridax procumbens, Tagetes patula, Tithonia diversifolia, Sphagneticola trilobata, Unxia suffruticosa, and Zinnia peruviana, and found that a 10% concentration extract reduced egg hatching by 89.96%, 91.13%, 92.48%, 92.72%, 93.2%, and 97.48%, respectively, compared to the eggs that were not exposed to the extract. In our study using rosemary, we observed an even greater reduction in the number of eggs hatched.…”