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Abstract

Effect of nematicidal compounds on hatchability of sugar beet cyst nematode, Heterodera schachtii and its infective juveniles was investigated. The sugar beet cyst nematode was isolated from Chinese cabbage field in Samcheok in Korea. Acute toxicity of nematicidal compounds against infective juveniles was also tested to find the LC 50 by exposing juveniles to given dilutions of each compound. Hatchability and mortality of infective juveniles of H. schachtii were influenced by nematicidal compounds (Fluopyram 40% SC, imicyafos 30% SC, fosthiazate 30% SC, abamectine 1.68% SC, terthiophene, and Eclipta prostrata extract). Fluopyram and imicyafos yielded the lowest rates of hatching. Total hatched infective juveniles were significantly different among nematicidal compounds. Positive correlation in percentage reduction of hatching was observed in fluopyram. Furthermore, the highest mortality was also observed in the treatments of fluopyram and imicyafos (LC 50 of 0.0543 and 0.0178 ppm respectively). The study, therefore, demonstrated available alternative nematicidal compounds which could be used in the control of H. schachtii.

Morphological and Molecular Characterization of Heterodera schachtii and the Newly Recorded Cyst Nematode, H. trifolii Associated with Chinese Cabbage in Korea

“…H. schachtii has already been identified as a serious setback in Chinese cabbage fields in Korea, and efforts in devising proper management and control strategies are underway (Kim et al, 2016; Kwon et al, 2016). However this study highlights the coexistence of H. schachtii and H. trifolii in Chinese cabbage fields and thus, management strategies should be formulated to target both pathogens.…”

“…Chinese cabbage, Brassica rapa chinensis L. (Bae-chu) is a highly valued economic crop and the leading vegetable in both production and consumption in Korea (Chang et al, 2008; Kim et al, 2014). Thus, pest and disease management is very crucial, and efforts to combat cyst nematodes are underway (Kim et al, 2016). However, correct species identification of plant parasitic nematodes is a vital milestone preceding successful nematode control and management strategies.…”

Efficacy of new nematicides for managing Meloidogyne incognita in tomato crop

“…It has an excellent biologically activity against all the stages of growth against various fungal plant pathogens belonging to Ascomycetes and Deuteromycetes on pome and stone fruit as well as vegetable crops (Veloukas & Karaoglanidis, 2012). Lately, its efficiency in the mitigation of plant-parasitic nematode damage was demonstrated (Broeksma et al, 2014;Jones et al, 2017;Kim et al, 2016). The application of fluazaindolizine reduced the reproduction of M. incognita in tomato plants cultivated in a greenhouse.…”

Mode of action of fluopyram in plant-parasitic nematodes

“…Although nematicidal activity of the compound is statistically significant at 50 ppm, we only documented a 21% paralysis rate of 48 h treated (50 ppm fluopyram) and 6 days recovered H. schachtii J2 in vitro. There was no impact on the number of developed nematodes on A. thaliana roots after transient exposure to fluopyram for 48 h. Kim et al 8 report that fluopyram is lethal for H. schachtii J2 with a 24 h LC 50 of 0.0543 ppm 8 . Reasons that possibly explain the differences between the reported LC 50 values and our observations and the conclusions are as follows: First, the authors do not specify how they decided whether a J2 is dead or not.…”

“…Fluopyram is reported to impact PPN: In vitro fluopyram reduces hatching of Meloidogyne incognita , Heterodera glycines , and Heterodera schachtii but not of Caenorhabditis elegans as the egg shell possesses limited permeability for the compound 7 , 8 . Fluopyram is reported to be of acute toxicity for M. incognita , M. javanica and H. schachtii infective juveniles (J2) 8 , 9 . Meloidogyne incognita and Rotylenchulus reniformis recover from fluopyram treatment whereas C. elegans does not 7 , 10 .…”