Silicates have the potential to induce disease resistance in plants. Induction of nematode resistance usually results from paralysis of nurse cell development or activation of the hypersensitivity response. This study aimed to evaluate the effects of silicon (Si) treatment on the penetration and development of Meloidogyne javanica in various crops. The experiment was set up in a randomized (3 × 4) + 1 factorial design, with 3 Si sources (Silifort®, Rocksil® and wollastonite), 4 crops (maize, rice, common bean and soybean) and 1 treatment control (distilled water). The Si treatments included adding wollastonite to the soil 10 days prior to seedling transplantation, or spraying with solutions of Silifort® or Rocksil®, 2 days after seedlings transplantation. Twelve days after transplantation, the plants were inoculated with 1000 eggs and eventual second‐stage juveniles (J2) of M. javanica. At 3, 8, 13 and 18 days after inoculation (DAI), the plants were harvested and nematode penetration evaluated by optical microscopy. All Si treatments adversely affected development of M. javanica in soybean, common bean and rice and reduced nematode penetration of rice roots. Silifort® and wollastonite reduced nematode penetration in common bean and soybean roots, respectively. However, none of the Si treatments influenced the variables analysed in maize. The results of this study illustrate the potential of Si treatment to control M. javanica parasitism in plants.

Root-knot nematodes are responsible for significant tomato production losses and require taking integrated control measures. The aim of the current study is to evaluate the association between biological control and organic matter sources to Meloidogyne javanica control in tomato. In order to do so, two experiments were carried out under greenhouse conditions, in two different periods. Tomato plants were transplanted to pots and inoculated with 2,000 M. javanica eggs. Plants were treated with either Nem-Out™ or Compost-Aid ® biological control products, which were individually applied or in association with organic wastes such as poultry litter, filter cake, rice hull and coffee hull. Nematological and vegetative parameters were evaluated 60 days later. The treatments, except for Nem-Out™ + poultry litter and Compost-Aid ® + poultry litter, were efficient in reducing the number of galls. Treatment with Nem-Out™ + filter cake presented 83% gall reduction, whereas Compost-Aid ® + filter cake presented 98.5% reduction. The associations between Nem-Out™ + poultry litter and Compost-Aid ® + poultry litter did reduce the number of nematodes g -1 of root. Reduction in this parameter were observed for all others treatments, mainly when there was association between biological control (both, Nem-Out™ and Compost-Aid ® ) and organic wastes; the treatment with Nem-Out™ + coffee hull reduced by 96% the number of nematodes g -1 of root, whereas the one with Compost-Aid ® + filter cake reduced it by 97%. Most of the treatments have positively influenced the vegetative variables in comparison to the inoculated control.

The aim of the study is to assess Crotalaria ochroleuca susceptibility to six Heterodera glycines races. To this, C. ochroleuca seedlings and two soybean cultivars were transplanted and individually inoculated with nematode races 1, 2, 3, 5, 6 and 14. Plants were collected and assessed 30 and 60 days after inoculation. Crotalaria ochroleuca reduced the number of females and the total number of eggs of the races 1, 2, 5 and 6. The reproduction of race 3 in crotalaria was equal to that of soybean cultivars in both assessment periods, whereas race 14 only reduced the reproduction in crotalaria to 60 days. Races 1 and 6 (30th day) and races 6 and 14 (60th day) showed number of eggs female-1 smaller than the controls. According to female index (FI), C. ochroleuca was resistant to races 1, 2 and 5, susceptible to race 3, and showed varying reactions to races 6 and 14.

Root-knot nematodes limit lettuce crop productivity. Efficient control is achieved through integrated management, and research about the efficiency of new products for nutrition and biological control is required. Thus, the objective of this study was to evaluate the effect of fertilizers, applied alone or in combination with microorganisms based product on the control of Meloidogyne javanica in lettuce. In the first research (research 1), conducted at two different periods, the products Agro-Mos®, Soil-SetTM and Copper-Crop® applied on shoots were evaluated; in research 2, the same products were applied isolated on shoots or associated to NemOutTM (Bacillus licheniformis, B. subtilis and Trichoderma longibrachiatum) applied to the soil. In research 1, the fertilizers Agro-Mos®, Soil-SetTM and Copper-Crop® applied alone promoted reduction in reproduction of M. javanica ranging from 31 to 75%, 36 to 79%, and 71 to 75%, respectively. The effect on plant development was variable, obtaining better results of fresh shoot mass applying Copper-Crop®. The combination of products did not have an additional effect on the control of the nematode, on the contrary, in general the products had antagonistic action. However, fertilizers and biological control applied isolated were efficient for nematode control.

Meloidogyne javanica and Pratylenchus brachyurus stand out among the main nematodes in soybean crops. Research on integrated management are often conducted, due to the low efficiency of the main control methods when they are applied alone. Thus, the aim of the present study was to assess the potential of biological control and plant nutrition products to control these nematodes in soybean. The effect of each product alone on nematode hatching and mortality was also assessed. A greenhouse experiment was also carried out, evaluating five doses of the product for biological control based on Bacillus and Trichoderma, with and without the presence of the product for nutrition, inoculated with 2000 eggs and juveniles for the gall nematode or 1000 specimens for the nematode lesions. After 30 days of multiplication, the aerial part was removed and the soil was revolved to receive the new sowing of the soybean with the respective treatments mentioned above. After 60 days, the experiments were evaluated for nematological parameters. Both products reduced hatching and increased nematode mortality. Treatments with biological control were efficient in reducing M. javanica and P. brachyurus, mainly when applied at doses close to 5 and 8 kg ha-1, respectively. The nutrition product negatively influences the biological control.