REAÇÃO DE MATERIAIS DE SORGO AOS NEMATOIDES Meloidogyne javanica, Meloidogyne incognita, Pratylenchus brachyurus

Abstract

Grain sorghum adapts well to different environments, which makes it possible to expand in regions with irregular rainfall distribution. Sorghum, which has the largest cultivation area after soybeans, can be useful in reducing nematode populations. The root lesion nematode (Pratylenchus brachyurus) has caused high economic damage to the soybean crop in Brazil. Among phytonematodes, root-knot nematodes (Meloidogyne spp.) are the most important phytoparasitic nematodes. The objective of this work was to evaluate the behavior of different sorghum hybrids to the nematodes P. brachyurus, M. javanica, M. incognita. A completely randomized experimental design was used, with four treatments and ten replications. The treatments were: T1- Hybrid MSP 222; T2 – Hybrid IRS 228; T3 – Hybrid IRS 322; T4 – Hybrid IRS 327. Three trials were set up, the first with Pratylenchus brachyurus, the second with Meloidogyne javanica and the third with Meloidogyne incognita. At 14 days after sowing, nematodes were inoculated. The evaluations were made at 70 days after inoculation (DAI) for the variable P. brachyurus, and 60 DAI for the variables Meloidogyne javanica, Meloidogyne incognita. The different hybrids behaved differently when inoculated with different nematodes. The hybrid IRS 228 in the variable P. brachyurus showed a low mean MFR, and it had the lowest amount of nematode. The variable M. incognita presented the highest mean MFR in this hybrid. For the variable M. javanica, the mean number of nematodes were the lowest, but their root development did not stand out.