Abstract
Fungi and bacteria associated to phytoparasitic nematodes Globodera rostochiensis and Meloidogyne spp. in Algeria were identified and characterized. Trichoderma spp. showed the highest prevalence in the cysts of G. rostochiensis. A number of isolates were identified through PCR amplification and the sequencing of the internal transcribed spacer (ITS)1-2 and Rpb2 gene regions. The most represented species were T. harzianum and T. afroharzianum. The latter and T. hirsutum were reported for the first time in Algeria. Fusarium spp., including F. oxysporum and F. solani, comprised a second group of fungi found in cysts. Taxa associated to females of Meloidogyne spp. included T. harzianum, Fusarium spp. and other hyphomycetes. To assess the efficacy of Trichoderma spp., two assays were carried out in vitro with the culture filtrates of two T. afroharzianum and T. harzianum isolates, to check their toxicity versus the second stage juveniles of M. incognita. After 24–48 h exposure, a mortality significantly higher than the control was observed for both filtrates at 1% dilutions. The TRI genes involved in the production of trichothecenes were also amplified with the PCR from some Trichoderma spp. isolates and sequenced, supporting a putative role in nematode toxicity. Bacteria isolated from the cysts of G. rostochiensis included Brucella, Rhizobium, Stenotrophomonas and Bacillus spp., identified through 16S rRNA gene sequencing. The potential of the microbial isolates identified and their mechanisms of action are discussed, as part of a sustainable nematode management strategy.
Highlights
Major plant pests such as plant-parasitic nematodes (PPNs) induce severe annual losses in agricultural and industrial crops, affecting their productivity worldwide
Bacteria isolated from the cysts of G. rostochiensis included Brucella, Rhizobium, Stenotrophomonas and Bacillus spp., identified through 16S rRNA gene sequencing
Among Fusarium spp. (24%), most isolates proceeded from the cysts of G. rostochiensis, with F. oxysporum (7%) as the most common species (Table 1)
Summary
Major plant pests such as plant-parasitic nematodes (PPNs) induce severe annual losses in agricultural and industrial crops, affecting their productivity worldwide. Meloidogyne (root-knot nematodes), Heterodera or Globodera (cyst nematodes), and Pratylenchus (lesion nematodes) are among the most economically important PPNs, due to the damage, host ranges and persistence in soil. Conventional pest management and the related agricultural practices based on pesticides are affected by the insurgence of resistance in pests or pathogens and by a number of environmental risks, including soil and water contamination. Many registered products applied for PPN control in conventional agriculture have been withdrawn from the market, because of their low specificity, toxicity and environmental impact [1]. The management of PPNs is challenging, in particular in sustainable and organic agriculture. There have been increasing efforts to develop sustainable management approaches
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
