Ácaros (Acari) de seringueira (Hevea brasiliensis Muell. Arg., Euphorbiaceae) e de euforbiáceas espontâneas no interior dos cultivos / Mites (Acari) from rubber trees (Hevea brasiliensis Muell. Arg., Euphorbiaceae) and spontaneous euphorbiaceous in rubber trees cultivation

Foram realizadas coletas trimestrais em 2001 em três cultivos de seringueira no Noroeste do estado de São Paulo. Foram amostradas três seringueiras de cada local. Nas entrelinhas das seringueiras foram coletadas quatro espécies de euforbiáceas espontâneas: Chamaesyce hirta, C. hyssopifolia, Euphorbia heterophylla e Phyllanthus tenellus. Foram coletados 8.954 ácaros de 38 espécies, pertencentes a 31 gêneros de 11 famílias. Tydeidae e Phytoseiidae tiveram maior diversidade de espécies, 9 e 7, respectivamente. As famílias mais abundantes foram Eriophyidae (3.594), Tydeidae (2.825) e Tenuipalpidae (1.027). As espécies mais abundantes nas seringueiras foram: fitófagas - Calacarus heveae Feres, Tenuipalpus heveae Baker, Lorryia sp.2, Lorryia formosa Cooreman e Lorryia sp.1; predadoras - Zetzellia quasagistemas Hernandes & Feres, Pronematus sp., Iphiseiodes zuluagai Denmark & Muma e Euseius citrifolius Denmark & Muma. Entre as euforbiáceas espontâneas, encontrou-se maior abundância de ácaros predadores em C. hirta e E. heterophylla, destacando-se Pronematus sp. e E. citrifolius, sugerindo que estas plantas possam ser importantes na manutenção daqueles predadores nos plantios de seringueira. No entanto, plantas que podem abrigar predadores, mas que também exercem forte competição (nutrientes, água etc.) com a seringueira, não podem ser sugeridas para um programa de manejo de pragas. Estudos sobre competição entre a seringueira e plantas espontâneas precisam ser conduzidos para viabilizar programas eficientes de manejo ambiental, visando o controle dos ácaros-praga da seringueira.

Quarterly samples were done in 2001 on three rubber tree plantation in the northwest of the state of São Paulo. Three rubber trees of each locality were sampled. Between the rows of rubber tree four species of spontaneous euphorbiaceous were collected: Chamaesyce hirta, C. hyssopifolia, Euphorbia heterophylla and Phyllanthus tenellus. A total of 8.954 mites of 38 species, belonging to 31 genera of 11 families were collected. Tydeidae and Phytoseiidae had the highest diversity of species, 9 and 7, respectively. The most abundant families were Eriophyidae (3.594), Tydeidae (2.825) and Tenuipalpidae (1.027). The most abundant species on the rubber trees were: phytophagous - Calacarus heveae Feres, Tenuipalpus heveae Baker, Lorryia sp.2, Lorryia formosa Cooreman and Lorryia sp.1; predators - Zetzellia quasagistemas Hernandes & Feres, Pronematus sp., Iphiseiodes zuluagai Denmark & Muma and Euseius citrifolius Denmark & Muma. Among the spontaneous euphorbiaceous, predatory mites were abundantly found on C. hirta and E. heterophylla, mainly Pronematus sp. and E. citrifolius, suggesting that these plants could be important in the maintenance of these predators in the rubber tree cultivation areas. However, plants that can shelter predators and at the same time exert strong competition (nutrients, water etc) to rubber trees, can not be recommended for pest management programs. Studies about competition between rubber trees and spontaneous plants need to be conducted for feasible efficient programs of environmental management, aiming at the control of pest mites of rubber tree.

Identification of excreted iron superoxide dismutase for the diagnosis of Phtytomonas

An excreted iron superoxide dismutase (FeSODe) of pI 3.6 with a molecular weight of 28-30 kDa was detected in the in vitro culture of Phytomonas isolated from Euphorbia characias (SODeCHA) and from Lycopersicon esculentum (SODeTOM), in Grace's medium without serum. These FeSODe excreted into the medium had immunogenic capacity: the positivity of the anti-SODeCHA serum persisted to a dilution of 1/30,000, and for the anti-SODeTOM to 1/10,000 by Western blot. In addition, cross reaction was detected between the anti-SODe serum of Phytomonas isolated from E. characias against SODeTOM, and the anti-SODe serum from L. esculentum with SODeCHA. This characteristic offers the possibility of its use to diagnose plant trypanosomatids. The validation of the test was confirmed by experimental inoculation of tomato fruits with Phytomonas isolated from L. esculentum. At 7, 10, 15, and 21 days post infection, it was possible to detect the presence of the parasites with the anti-SODe serum of Phytomonas isolated from L. esculentum at a dilution of 1/250. These serological results were confirmed by visualization of the parasites by optical microscopy. The data of this study confirm that the SOD is sufficient to identify a trypanosomatid isolated from plants as belonging to the genus Phytomonas.

Evaluation of Leishmanicidal effect of Euphorbia myrisinites extract by in vitro antileishmanial assay using promastigote of Leishmania.major

In this study, the antileishmanial effect of different extracts of Euphorbia myrsinites aerial part was evaluated on promastigotes of Leishmania major in vitro. Dried and ground aerial parts of the plant were extracted using either maceration in 80% ethanol or soxhlet in methanol. Then 5 different concentrations of each extract, one positive control, one negative control, and one solvent control were prepared and placed in a 24-well plate containing 40, 000 parasites/well. The extract concentrations were 0.06, 0.12, 0.25, 0.5 and 1 mg/ml. Amphotricin B [0.5 mg/ml] was used as positive control while negative control contained only culture medium. The plate was incubated at 25°C for six days, and the amount of parasites in each well was determined on days 2, 4, and 6 of experiment microscopically using Neubar chamber. It was observed that amphotricin B and both macerated and soxhlet extracts at concentration of 1 mg/ml killed all parasites. Lower doses exhibited a dose-dependent antileishmanial activity. The ECso for macerated and soxhlet extracts in DMSO was between 0.5 and 0.25 mg/ml. The control solvents had no significant effect on the L. major promastigotes. These results indicated that both macerated and soxhlet extracts of E. myrsinites have favorable leishmanicidal activity