<abstract xmlns="http://www.w3.org/1999/xhtml"><p>Southern root-knot nematode (RKN, <italic>Meloidogyne incognita</italic>) is a serious pest of cultivated watermelon (<italic>Citrullus lanatus</italic> var. <italic>lanatus</italic>) in southern regions of the United States and no resistance is known to exist in commercial watermelon cultivars. Wild watermelon relatives (<italic>Citrullus lanatus</italic> var. <italic>citroides</italic>) have been shown in greenhouse studies to possess varying degrees ofresistance to RKN species. Experiments were conducted over 2 yr to assess resistance of southern RKN in <italic>C. lanatus</italic> var. <italic>citroides</italic> accessions from the U.S. Watermelon Plant Introduction Collection in an artificially infested field site at the U.S. Vegetable Laboratory in Charleston, SC. In the first study (2006), 19 accessions of <italic>C. lanatus</italic> var. <italic>citroides</italic> were compared with reference entries of <italic>Citrullus colocynthis</italic> and <italic>C. lanatus</italic> var. <italic>lanatus</italic>. Of the wild watermelon accessions, two entries exhibited significantly less galling than all other entries. Five of the best performing <italic>C. lanatus</italic> var. <italic>citroides</italic> accessions were evaluated with and without nematicide at the same field site in 2007. <italic>Citrullus lanatus</italic> var. <italic>citroides</italic> accessions performed better than <italic>C. lanatus</italic> var. <italic>lanatus</italic> and <italic>C. colocynthis</italic>. Overall, most entries of <italic>C. lanatus</italic> var. <italic>citroides</italic> performed similarly with and without nematicide treatment in regard to root galling, visible egg masses, vine vigor, and root mass. In both years of field evaluations, most <italic>C. lanatus</italic> var. <italic>citroides</italic> accessions showed lesser degrees of nematode reproduction and higher vigor and root mass than <italic>C. colocynthis</italic> and <italic>C. lanatus</italic> var. <italic>lanatus</italic>. The results of these two field evaluations suggest that wild watermelon populations may be useful sources of resistance to southern RKN.</p></abstract>

Southern root-knot nematode (RKN, Meloidogyne incognita) is a serious pest of cultivated watermelon (Citrullus lanatus var. lanatus) in southern regions of the United States and no resistance is known to exist in commercial watermelon cultivars. Wild watermelon relatives (Citrullus lanatus var. citroides) have been shown in greenhouse studies to possess varying degrees ofresistance to RKN species. Experiments were conducted over 2 yr to assess resistance of southern RKN in C. lanatus var. citroides accessions from the U.S. Watermelon Plant Introduction Collection in an artificially infested field site at the U.S. Vegetable Laboratory in Charleston, SC. In the first study (2006), 19 accessions of C. lanatus var. citroides were compared with reference entries of Citrullus colocynthis and C. lanatus var. lanatus. Of the wild watermelon accessions, two entries exhibited significantly less galling than all other entries. Five of the best performing C. lanatus var. citroides accessions were evaluated with and without nematicide at the same field site in 2007. Citrullus lanatus var. citroides accessions performed better than C. lanatus var. lanatus and C. colocynthis. Overall, most entries of C. lanatus var. citroides performed similarly with and without nematicide treatment in regard to root galling, visible egg masses, vine vigor, and root mass. In both years of field evaluations, most C. lanatus var. citroides accessions showed lesser degrees of nematode reproduction and higher vigor and root mass than C. colocynthis and C. lanatus var. lanatus. The results of these two field evaluations suggest that wild watermelon populations may be useful sources of resistance to southern RKN.

Resistance to Southern Root-knot Nematode (<italic>Meloidogyne incognita</italic>) in Wild Watermelon (<italic>Citrullus lanatus</italic> var. <italic>citroides</italic>)

Journal of Nematology

This work is licensed under the Creative Commons Attribution 4.0 International License.

Resistance to Southern Root-knot Nematode () in Wild Watermelon ( var. )

Southern root-knot nematode (RKN, Meloidogyne incognita) is a serious pest of cultivated watermelon (Citrullus lanatus var. lanatus) in southern regions of the...

Resistance to Southern Root-knot Nematode (Meloidogyne incognita) in Wild Watermelon (Citrullus lanatus var. citroides)

Published Online: Jul 21, 2017

Page range: 14 - 19

Received: Oct 01, 2008

DOI: https://doi.org/10.21307/jofnem-2017-004

Keywords
var., var., plant introduction, resistance, southern root-knot nematode, wild watermelon

© 2016 Judy A. Thies et al., published by Sciendo

This work is licensed under the Creative Commons Attribution 4.0 International License.

Resistance to Southern Root-knot Nematode (Meloidogyne incognita) in Wild Watermelon (Citrullus lanatus var. citroides)

Published Online: Jul 21, 2017

Page range: 14 - 19

Received: Oct 01, 2008

DOI: https://doi.org/10.21307/jofnem-2017-004

Keywordsvar., var., plant introduction, resistance, southern root-knot nematode, wild watermelon

© 2016 Judy A. Thies et al., published by Sciendo

This work is licensed under the Creative Commons Attribution 4.0 International License.

Keywords
var., var., plant introduction, resistance, southern root-knot nematode, wild watermelon