Biological attributes of Salibro™, a novel sulfonamide nematicide. Part 2: Impact on the fitness of various non-target nematodes

Nematology ◽  
2020 ◽  
pp. 1-17 ◽  
Author(s):  
Tim C. Thoden ◽  
Mariam A. Alkader ◽  
John A. Wiles

Summary Currently a renaissance in chemical nematicides is taking place with novel products like Nimitz® (a.s. fluensulfone), Velum Prime® (a.s. fluopyram) and Salibro™ (a.s. fluazaindolizine – Reklemel™ active) entering the marketplace. Although a considerable amount of published data is already available on their laboratory and field impact on plant-parasitic nematodes, little is understood of their compatibility with the beneficial or free-living nematodes that are part of the soil health network. In a range of laboratory studies, the effects of these nematicides on the vitality and reproduction of several species was tested, including both cosmopolitan free-living nematodes (Acrobeloides, Cruznema, Panagrobelus) as well as commercially applied entomopathogenic nematodes (Steinernema, Heterorhabditis). Within aqueous exposure and agar plate in vitro assays, species sensitivity to those nematicides differed significantly but their fitness (vitality and reproduction; infectivity to insect hosts) was generally not adversely impacted by concentrations of 5-50 ppm (a.s.) of Salibro. Even at 250 ppm (a.s.) of Salibro only some species of the bacterial-feeding species showed some negative impact. By contrast, both Nimitz at 50 ppm (a.s.) and Velum at 5 ppm (a.s.) consistently demonstrated stronger adverse impacts. In second level soil drenching assays, either no, or occasionally slight, adverse effects on the natural community of free-living nematodes were observed if soils were drenched with different volumes of Salibro at 5-50 ppm (a.s.), while relatively stronger reductions were measured within the plant-parasitic species (especially root-knot nematodes). Both Nimitz and Vydate (a.s. oxamyl) showed some degree of compatibility at 5 and 25 ppm (a.s.), respectively, which was generally higher than for Velum Prime at 5 ppm (a.s.). Overall, these data indicate that, when used at common field rates, Salibro will be one of the best options as part of integrated nematode management programmes where the use of chemical nematicides is required.

2016 ◽  
Vol 283 (1835) ◽  
pp. 20160942 ◽  
Author(s):  
Jinshui Zheng ◽  
Donghai Peng ◽  
Ling Chen ◽  
Hualin Liu ◽  
Feng Chen ◽  
...  

Plant-parasitic nematodes were found in 4 of the 12 clades of phylum Nematoda. These nematodes in different clades may have originated independently from their free-living fungivorous ancestors. However, the exact evolutionary process of these parasites is unclear. Here, we sequenced the genome sequence of a migratory plant nematode, Ditylenchus destructor . We performed comparative genomics among the free-living nematode, Caenorhabditis elegans and all the plant nematodes with genome sequences available. We found that, compared with C. elegans , the core developmental control processes underwent heavy reduction, though most signal transduction pathways were conserved. We also found D. destructor contained more homologies of the key genes in the above processes than the other plant nematodes. We suggest that Ditylenchus spp. may be an intermediate evolutionary history stage from free-living nematodes that feed on fungi to obligate plant-parasitic nematodes. Based on the facts that D. destructor can feed on fungi and has a relatively short life cycle, and that it has similar features to both C. elegans and sedentary plant-parasitic nematodes from clade 12, we propose it as a new model to study the biology, biocontrol of plant nematodes and the interaction between nematodes and plants.


2020 ◽  
Vol 110 (12) ◽  
pp. 2003-2009
Author(s):  
Catherine L. Wram ◽  
Inga Zasada

This research focused on the effects of fluazaindolizine on a diversity of plant-parasitic nematodes. In microwell assays, 24-h dose-response curves were generated for several species and populations of Meloidogyne, Pratylenchus neglectus, P. penetrans, Globodera ellingtonae, and Xiphinema americanum. In a greenhouse study, the impact of fluazaindolizine on fecundity of M. incognita, M. hapla, and M. chitwoodi was tested by exposing nematodes for 24 h in solution and inoculating on tomato. The average 24-h ED50s (dose that resulted in the immobility of 50% of exposed nematodes) for M. hapla, M. chitwoodi, and M. incognita were 325.7, 223.4, and 100.7 ppm, respectively. M. hapla had the most variation among populations, with 24-h ED50s ranging from 72 to 788 ppm. G. ellingtonae had the lowest 24-h ED50 at 30 ppm. Pratylenchus spp. were unaffected by fluazaindolizine. X. americanum was the only species where effects of fluazaindolizine were reversible, but had a 24-h ED50 that fell in the range of the Meloidogyne spp. In the greenhouse study, M. chitwoodi was the least sensitive with reproduction reaching 62% of the untreated control after a pre-exposure to 47 ppm, whereas M. incognita and M. hapla at the same exposure dose had reproduction rates of 27 and 36% of the untreated control, respectively. Despite varying in in vitro responses to fluazaindolizine, reproduction of all Meloidogyne spp. was suppressed after only 24 h of exposure. This study expanded our understanding of how G. ellingtonae, P. thornei, P. penetrans, and X. americanum respond to fluazaindolizine.


Plants ◽  
2020 ◽  
Vol 9 (4) ◽  
pp. 443 ◽  
Author(s):  
Trifone D’Addabbo ◽  
Maria Pia Argentieri ◽  
Jerzy Żuchowski ◽  
Elisa Biazzi ◽  
Aldo Tava ◽  
...  

Content of bioactive saponins of Medicago species suggests that they may also exert, as previously demonstrated on M. sativa, nematicidal properties exploitable for the formulation of new products for sustainable phytoparasitic nematode management. This study was addressed to highlight the bioactivity of saponins from five different Medicago species still poorly known for their biological efficacy, i.e., M. heyniana, M. hybrida, M. lupulina, M. murex and M. truncatula, against the plant parasitic nematodes Meloidogyne incognita, Xiphinema index and Globodera rostochiensis. The bioactivity of the extracts from the five Medicago species was assessed by in vitro assays on the juveniles (J2) and eggs of M. incognita and G. rostochiensis and the adult females of X. index. The suppressiveness to M. incognita of soil treatments with the Medicago plant biomasses was also investigated in a tomato experiment. The nematicidal activity of the five Medicago species was reported and discussed in relation to their phytochemical profile.


2011 ◽  
Vol 48 (2) ◽  
pp. 124-136 ◽  
Author(s):  
V. Čermák ◽  
V. Gaar ◽  
L. Háněl ◽  
K. Široká

AbstractComposition and vertical distribution of soil nematode communities within soil profile were investigated in eight hop gardens in Czech Republic. In total, the presence of 78 nematode genera was confirmed. Genus Drilocephalobus (Coomans & Coomans, 1990) is new for fauna of the Czech Republic. The highest abundance of soil nematodes was found at a depth of 0–10 cm and declined with increasing depth of soil profile. The most dominant genus was Bitylenchus, followed by genera Acrobeloides, Ditylenchus, Chiloplacus and Cervidelus. Ten genera of plant parasitic nematodes were recorded: Bitylenchus (with prevalence of B. dubius), Helicotylenchus, Heterodera (with absolute prevalence of H. humuli), Geocenamus, Longidorella, Longidorus (only L. elongatus), Merlinius (with prevalence of M. brevidens), Paratylenchus and Pratylenchus. Low population densities of predators and omnivores, low values of the community indices (MI, ΣMI, SI, and CI), and high values of NCR, EI, and PPI/MI ratio indicated disturbed nematode communities in hop gardens and bacteria-dominated decomposition pathways in the soil food web.


Nematology ◽  
2012 ◽  
Vol 14 (7) ◽  
pp. 869-873 ◽  
Author(s):  
Ayano Sasaki-Crawley ◽  
Rosane Curtis ◽  
Michael Birkett ◽  
Apostolos Papadopoulos ◽  
Rod Blackshaw ◽  
...  

This paper demonstrates a simple novel in vitro method using Pluronic F-127 aqueous solution to study the development of the potato cyst nematode, Globodera pallida, in Solanum spp. without any need for sterilisation of either the plants or the nematodes. In this study, this method was successfully applied to comparative studies on the development of G. pallida in Solanum tuberosum (potato) or S. sisymbriifolium (sticky nightshade). The protocol described here could be useful for screening transgenic plants or different plant cultivars/species for their ability to allow development not only of G. pallida but also any other plant-parasitic nematodes.


Nematology ◽  
2017 ◽  
Vol 19 (3) ◽  
pp. 271-280 ◽  
Author(s):  
Julio C.P. Silva ◽  
Vicente P. Campos ◽  
Eduardo S. Freire ◽  
Willian C. Terra ◽  
Liliana E. Lopez

Ethanol (EtOH) is less harmful to humans than currently available nematicide molecules. This study evaluated the efficacy of EtOH in controlling Meloidogyne incognita in vitro and in lettuce plants under glasshouse conditions. Aqueous EtOH solutions (5-70% volume) and their vapours caused an acute nematicidal effect in vitro in second-stage juveniles (J2) of M. incognita and reduced hatching of J2. There was a large reduction of galls and eggs in the root system when 40 ml of EtOH was applied to M. incognita-infested soil at concentrations of 40 and 70%. Water exposed to EtOH vapours for 1 h became toxic, and a 12-h exposure caused 100% J2 mortality. Use of a plastic cover did not increase the efficiency of EtOH in controlling M. incognita in lettuce plants. The observed EtOH effects indicate its prospective use in controlling plant-parasitic nematodes, especially in glasshouses.


Sign in / Sign up

Export Citation Format

Share Document