Reproduction of Meloidogyne javanica in crambe plant and influence on crop yield and oil content

Abstract

The crambe is an oilseed plant of the Brassicaceae family, which has the potential to grow in the winter, in succession to soybean crop, and whose seeds have been used for extraction of oil for biofuel production. However, in areas with nematode infestation, special care is needed in the selection of the species to be used in crop succession. Thus, the present study aimed to assess the susceptibility of crambe to plant-parasitic nematode, Meloidogyne javanica and its interference in vegetative growth parameters: crop yield and seed oil content. Therefore, crambe (Crambe abyssinica Hochst) seedlings were inoculated with a suspension containing 0, 1300, 2600 and 5200 eggs and second-stage juveniles (J2) of M. javanica, in experiment 1 (January to March, 2012), and 0, 1000, 2000 and 4000 eggs and J2, in experiment 2 (May to July, 2012). The tomato plant was inoculated to assess the viability of the inoculum. The assessments were done at two different times: 60 days after inoculation, assessment of the nematode reproduction factor, plant height and fresh and dry mass of the aerial part, was done with four repetitions. At the end of the crop cycle, 90 days after inoculation, seed yield and oil content were assessed in the remaining four replications. When grown in a period of higher temperatures, the crambe showed susceptibility to root-knot nematodes, with a negative impact on plant yield. However, this did not occur when the plant was grown in a more favorable season. In both experiments, seed oil content was not affected by the presence of the nematode.