Agronomic performance of selected sweet potato cultivars under greenhouse and field infested with meloigogyne incognita and soilborne insect pests.

The root knot nematode (RKN), Meloidogyne incognita, is widespread worldwide and a major pathogen of several cultivated crops. The use of resistant genotypes is the most effective and environmentally sound way to manage RKN. In this study, we screened 16 selected sweet potato cultivars including Amanda, Bárbara, Beatriz, Beauregard, Brazlândia Branca, Brazlândia Rosada, Brazlândia Roxa, BRS Amélia, BRS Cuia, BRS Rubissol, Carolina Vitória, Duda, Júlia, Marcela, PA-26/2009, and Princesa obtained from Embrapa and Universidade Federal do Tocantins? germplasm bank. Studies were conducted under greenhouse and field conditions and the agronomic performance of the cultivars was evaluated in a nematode and soilborne insect-infested field. All 16 sweet potato cultivars tested were rated as resistant to this nematode both under greenhouse and field conditions with reproduction factors < 1. In the field infested with M. incognita, sweet potato cultivars Duda, BRS Amélia, Beauregard, Brazlândia Rosada, and Brazlândia Roxa stood out as superior cultivars, with average yield ranging from 26 to 47 tons per ha. Overall, most cultivars exhibited a fusiform to near fusiform root shape, a good characteristic for the market, and were moderately affected by insects (attack incidence 1 to 30%). As global demand for energy continues to rise, selecting new cultivars of sweet potatoes with increased resistance to nematode diseases and with high yield will be important for food security and biofuel production.

Nematoides associados a cinco fruteiras no estado do Amapá, Brasil.

The aim of this study was to conduct a survey on nematodes associated with five cultivated fruit trees growing in the Agroforestry System (AFS) of the municipality of Oiapoque, Amapá, Brazil. Rhizosphere samples were collected from three points at the base of murici (Byrsonima sp.), soursop (Annona muricata), cupuaçu (Theobroma grandiflorum), passion fruit (Passiflora sp.) and peach palm (Bactris gasipaes) trees. Four species of phytonematodes were identified, namely Pratylenchus brachyurus, Helicotylenchus dihystera, Mesocriconema xenoplax and Rotylenchulus reniformis. The most prevalent and abundant species was R. reniformis, which was found in the rhizospheres of passion fruit, cupuaçu, soursop, and peach palm. The first record in Brazil of the nematode P. brachyurus, found in the roots of murici is reported here, and all of the nematode species identified here are the first records for fruit trees in the state of Amapá.

Resistance to Meloidogyne incognita, Meloidogyne javanica and Pratylenchus brachyurus in sunflower cultivars adapted to the tropical region of Brazil.

The continuous soybean-maize crop succession in the tropical region of Brazil has led to significant increases in the population size of root-knot (Meloidogyne incognita and M. javanica ) and root-lesion nematodes (Pratylenchus brachyurus), which make soils unsuitable for soybean cropping. A greenhouse study was conducted to identify sunflower genotypes adapted to the tropical region of Brazil and that are resistant to M. incognita, M. javanica and/or P. brachyurus . Two experiments for each nematode were conducted in a completely randomized design with six replicates. Gall index was calculated from visual scores (0?5) of gall intensity on roots for the root-knot nematode. Initial and final population density and reproduction factor were also measured for each nematode. Sunflower genotypes varied in resistance to the nematodes. Sunflower hybrids BRS 321 and BRS 323 were resistant to M. javanica and P. brachyurus and exhibited low gall index for M. incognita . The cultivars are good alternatives to using in the succession of soybean in nematode-infested areas of the tropical regions of Brazil. No sunflower genotype was identified as resistant to M. incognita and thus sunflower cropping is not indicated in areas infested with this nematode.

Grassing as potential factor in Gastrointestinal Nematodiasis in Goat in Banyumas District

Goat system manajemen like housing, feeding dan grassing have been studied on the diseases association in gastrointestinal nematodiasis infection. The method applied was survey on 150 goat (Jawarandhu) faeces sample in Banyumas District. The Research was carried out from July to September 2004. The result showed that  the nematode infection 1,54 times to goat if grassing and 88,62% infection in groups. Housing, Feeding have no risk and associated with disease infection. (Animal Production 6(2): 95-100 (2004) Key words : management system, disease association, nematode