Host suitability of grain sorghum and sudangrass for Pratylenchus brachyurus

Abstract

Nowadays, the root-lesion nematode Pratylenchus brachyurus (Godfrey) is a major pest of soybean in Brazil, mainly in areas using double cropping with maize or cotton, which are suitable hosts for P. brachyurus. A great effort has been made to find cash crops for P. brachyurus management. Grain sorghum [Sorghum bicolor (L.)] was classified as a non-host for P. brachyurus but based on a single trial. It would be a valuable option as a culture for double cropping with soybean, as it is profitable and can be used in root-lesion nematode management. Sudangrass (S. bicolor var. sudanense) is not directly profitable, but Brazilian farmers favor it because it can produce pasture, green chop, silage, or hay under unfavorable hydric conditions. However, no information is available regarding the suitability of sudangrass for P. brachyurus. Thus, the current study aimed to assess the suitability of grain sorghum and sudangrass for P. brachyurus in two glasshouse trials. The first trial tested sudangrass and grain sorghum ‘DKB 510’, ‘Dow 740’, ‘Dow 822’, ‘DKB 599’, and ‘AG 1040’. The second trial retested sudangrass and grain sorghum ‘Dow 740’ and ‘DKB 599’. The results demonstrated that sudangrass and grain sorghum were suitable hosts for P. brachyurus. These results, in addition to those obtained for other types of sorghum, emphasize that S. bicolor and sudangrass should be avoided in fields infested with P. brachyurus, as they increase the nematode population.

Host Status of Cover Crops for the Management of Pratylenchus jaehni on Coffee

“…Showy rattlebox was never tested for its host status on P. jaehni. This cover crop has been largely used in double-crop with soybean to manage P. brachyurus, mainly in the Central-West region of Brazil, with an estimated 4 million ha sowed in 2018 (Souza and Inomoto, 2019). It is considered as a non-host to P. brachyurus (Machado et al, 2007).…”

An emergent plant‐parasitic nematode in Brazil: Aphelenchoides besseyi. Current status and research perspectives

“…This is one of the oldest techniques to reduce the damage of pathogens and pests (Chen & Tsay, 2006;Sasanelli et al, 2021). In Brazil, crop rotation/succession has been largely used to manage important species of PPNs, for example, soybean followed by maize/cotton against H. glycines Debiasi et al, 2016;Souza & Inomoto, 2019). However, polyphagous species of nematodes limit the options available to farmers to less profitable crops, such as Crotalaria spp.…”

“…However, polyphagous species of nematodes limit the options available to farmers to less profitable crops, such as Crotalaria spp. (Asmus et al, 2016;Dias et al, 2010;Rodrigues et al, 2014;Souza & Inomoto, 2019). Some plant species were identified as nonhosts to A. besseyi and could be used in its management.…”

“…The authors pointed out that their use contributed with maintenance of A. besseyi in common bean fields. The crop to be used in rotation/succession should be carefully chosen based on the context of the area, including the presence of other PPNs (Inomoto & Asmus, 2010;Souza & Inomoto, 2019).…”