Host status of progenies of yellow passion fruit to Meloidogyne incognita race 2

The host status of eighteen progenies (CRP 01-12 to CRP 16-12, CRP 19-12 and CRP 20-12) and two cultivars (FB 200 Yellow Master and FB 300 Araguari) of yellow passion fruit to Meloidogyne incognita race 2 was evaluated in a greenhouse experiment. The height and the biomass of the plants, besides the numbers of galls, eggs and second-stage juveniles in roots and soil were assessed after 70 days of cultivation of the genotypes and tomato (control) in plastic pots with 2 kg of soil infested with 5,000 eggs of the nematode. The reproduction factor of the pathogen (RF = Final population/Initial population) was calculated for classifying the genotypes as immune (RF = 0), resistant (RF < 1) or susceptible (RF ≥ 1). The cultivar FB 200 is resistant to M. incognita race 2 and can be cultivated in areas infested with this nematode

Densidade populacional de Pratylenchus spp. em pastagens de Brachiaria spp. e sua influência na disponibilidade e na qualidade da forragem

The aim of this work was to evaluate the population density of Pratylenchus brachyurus and Pratylenchus zeae associated with Brachiaria brizantha, B. decumbens and B. humidicola and their influence on forage availability and quality. The experiment was conducte in the Hisaeda Farm, Terenos, MS, Brazil. Soil, roots and plant aerial part were harvest with ten replications each, in one square meter randomized sets encompassing three treatments: Good, Intermediary and Bad, visually characterized, considering the percentage of green material. P. brachyurus and P. zeae density were evaluated in soil and plant roots. Dry matter of green, dead and re-growth materials, plant nutritional status and forage quality were assessed in the aerial plant part. Soil fertility was determined in all harvested samples. Both nematode species were identified from all samples, with a larger numbe in the roots (between 87-311 P. brachyurus and 1-61 P. zeae.10 g-1) than in the soil (0-8 P. brachyurus and 1-39 P. zeae.200 cm-3), however, no significant differences were found in the number of specimens between treatments. Considering that these forage species are perennial and host Pratylenchus spp, there is a tendency to increase the population of these pathogens over time, becoming a serious phytosanitary problem.Laboratório de Fitopatologia Embrapa Gado de Corte, BR 262 Km 4, Caixa Postal 154, 79002-970, Campo Grande, Mato Grosso do SulDepartamento de Fitossanidade Universidade Estadual Paulista Júlio de Mesquita Filho, Via de acesso Paulo Donato Castellane s/n, 14884-900, Jaboticabal, São PauloDepartamento de Fitossanidade Universidade Estadual Paulista Júlio de Mesquita Filho, Via de acesso Paulo Donato Castellane s/n, 14884-900, Jaboticabal, São Paul